Sulfonated Block Polyesters Useful as Soil Release Agents in Detergent Compositions

The present application relates to block polyesters and like compounds useful as soil release agents in laundry detergent compositions.

In addition to cleaning performance, laundry detergent compositions desirably have other benefits. One is the ability to confer soil release properties to fabrics woven from polyester fibers. These fabrics are mostly co-polymers of ethylene glycol and terephthalic acid, and are sold under a number of tradenames, e.g. Dacron, Fortrel, Kodel and blue C Polyester. The hydrophobic character of polyester fabrics makes their laundering difficult, particularly as regards oily soil and oily stains. The oily soil or stain preferentially "wets" the fabric. As a result, the oily soil or stain is difficult to remove in an aqueous laundering process.

High molecular weight (e.g., 40,000 to 50,000 M.W.) polyesters containing random ethylene terephthalate/polyethylene glycol (PEG) terephthalate units have been used as soil release compounds in laundry detergent compositions. See U.S. Pat. No. 3,962,152 to Nicol et al., issued June 8, 1976. During the laundering operation, these soil release polyesters adsorb onto the surface of fabrics immersed in the wash solution. The adsorbed polyester then forms a hydrophilic film which remains on the fabric after it is removed from the wash solution and dried. This film can be renewed by subsequent washing of the fabric with a detergent composition containing the soil release polyesters.

These ethylene terephthalate/PEG terephthalate polyesters are not very water-soluble. It is believed that they form a suspension in the wash solution which does not adsorb efficiently onto the fabrics. As a result, the level of soil release polyester in the detergent composition has to be increased if benefits are to be obtained after several wash cycles. Because of this poor water-solubility, these polyesters are formulated as suspensions in laundry detergent compositions, rather than as isotropic liquids. In certain detergent formulations, these polyesters can also diminish clay soil cleaning performance.

A. Polyester anti-static agents formed from dimethyl terephthalate, ethylene glycol and methoxy PEGs.

U.S. Pat. No. 3,416,952 to McIntyre et al., issued Dec. 17, 1968, discloses the treatment of shaped polyester articles with a water-insoluble crystallizable polymeric compound which can contain a water-solvatable polymeric group such as a polyoxyalkylene group having an average molecular weight of from 300-6000. Preferred polyoxylalkylene groups are the PEGs having an average molecular weight of from 1000-4000. Treatment of the shaped articles is carried out by applying an aqueous dispersion of the crystallizable polymeric compound in the presence of an anti-oxidant, followed by heating to a temperature above 90.degree. C. to obtain a durable coating of the compound on the shaped article. Example 6 discloses one such crystallizable polymeric compound formed by the reaction of dimethyl terephthalate, ethylene glycol and an O-methyl poly(oxyethylene) glycol of average molecular weight 350. A 20% solution of this polyester in benzyl alcohol was used to impart anti-static properties to a polyester fabric. Example 7 discloses a 20% aqueous solution of a similar polyester used to impart anti-static properties to a polyester fabric.

B. Polyester anti-static and soil release agents formed from dimethyl terephthalate, sodium dimethyl 5-sulphoisophthalate, ethylene glycol and polyethylene glycol (PEG)

U.S. Pat. No. 4,427,557 to Stockburger, filed Feb. 15, 1983, issued Jan. 24, 1984, discloses low molecular weight copolyesters (M.W. 2,000 to 10,000) which can be used in aqueous dispersions to impart soil release properties to polyester fibers. The copolyesters are formed by the reaction of ethylene glycol, a PEG having an average molecular weight of 200 to 1000, an aromatic dicarboxylic acid (e.g. dimethyl terephthalate), and a sulfonated aromatic dicarboxylic acid (e.g. dimethyl 5-sulfoisophthalate). The PEG can be replaced in part with monoalkylethers of PEG such as the methyl, ethyl and butyl ethers. A dispersion or solution of the copolyester is applied to the textile material and then heat set at elevated temperatures (90.degree. to 150.degree. C.) to impart durable soil release properties.

C. Monomeric polyesters of PEG and terephthalic acid useful as soil release agents

U.S. Pat. No. 4,394,688 to Sandler, issued Sept. 14, 1982, discloses polyoxyalkylene ester soil release agents, in particular monomeric polyesters of PEG and terephthalic acid having the formula: ##STR2## where n can range from 6-23 and X is either methyl or H. Example IV discloses the preparation of one such PEG/terephthalate polyester formed from terephthaloyl chloride and Carbowax 400 (n=9, X=H). Durable soil resistancy and water wicking properties are imparted by wetting the fabric with a composition containing the polyoxylalkylene ester, drying the wetted fabric, and then curing the dried fabric at a temperature of from 190.degree. C.-200.degree. C. for about 45-90 seconds.

D. Ethylene terephthalate/PEG terephthalate soil release polyesters for fabric treating solutions.

U.S. Pat. No. 3,959,230 to Hays, issued May 25, 1976, discloses polyester soil release agents containing random ethylene terephahalate/PEG terephthalate units in a mole ratio of from about 25:75 to about 35:65. These soil release polyesters have a molecular weight of from about 25,000 to about 55,000, (preferably from about 40,000 to about 55,000) and are used in dilute, aqueous solutions, preferably with an emulsifying agent present. Fabrics are immersed in this solution so that the soil release polyester adsorbs onto the fabric surface. The polyester forms a hydrophilic film which remains on the fibers after the fabric is removed from the solution and dried. See also U.S. Pat. No. 3,893,929 to Basadur, issued July 8, 1975 (compositions for imparting soil release finish containing a polyester having an average molecular weight of 3000-5000 formed from terephthalic acid, PEG and ethylene glycol); U.S. Pat. No. 3,712,873 to Zenk, issued Jan. 23, 1973, (textile treating compositions comprising fatty alcohol polyethoxylates; quaternary ammonium compounds; a polyester having average molecular weight of 3000-5000 formed from terephthalic acid, PEG and ethylene glycol; and starch).

E. Ethylene terephthalate/PEG terephthalate soil release agents used in detergent compositions.

U.S. Pat. No. 3,962,152 to Nicol et al., issued June 8, 1976, discloses detergent compositions containing detergent surfactants and the ethylene terephthalate/PEG terephthalate soil release polyesters disclosed in the Hays patent. See also U.S. Pat. No. 4,116,885 to Derstadt et al., issued Sept. 26, 1978 (detergent compositions containing certain compatible anionic detergent surfactants and ethylene terephthalate/PEG terephthalate soil release polyesters); U.S. Pat. No. 4,132,680 to Nicol, issued Jan. 2, 1979 (detergent compositions containing detergent surfactants; a composition which disassociates to yield quaternary ammonium cations; and an ethylene terephthalate/PEG terephthalate soil release polyester).

F. Soil release and antistatic polyurethanes useful in detergent compositions which contain polyester blocks having sulfoisophthalate units.

U.S. Pat. No. 4,201,824 to Violland et al., issued May 6, 1980, discloses hydrophilic polyurethanes having soil release and antistatic properties useful in detergent compositions. These polyurethanes are formed from the reaction product of a base polyester with an isocyanate prepolymer (reaction product of diisocyanate and macrodiol). Example VI discloses a base polyester formed from dimethyl terephthalate, dimethyl sulfoisophthalate, ethylene glycol and PEG (molecular weight 300) which is reacted with a prepolymer formed from a PEG (molecular weight 1,500) and toluene diisocyanate.

The present invention relates to compounds of formula:

wherein the A moieties are essentially ##STR3## moieties; the R.sup.1 moieties are essentially 1,4-phenylene moieties; the R.sup.2 moieties are essentially ethylene moieties, or substituted ethylene moieties having C.sub.1 -C.sub.4 alkyl or alkoxy substitutents; the R.sup.3 moieties are substituted C.sub.2 -C.sub.18 hydrocarbylene moieties having at least one --SO.sub.3 M, --COOM, --O--(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n --X or --A--(R.sup.2 --A--R.sup.4 --A)].sub.w [(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n --X substituent or at least one moiety --A--(R.sup.2 --A--R.sup.4 --A)].sub.w R.sup.2 --A-- crosslinked to another R.sup.3 moiety; the R.sup.4 moieties are R.sup.1 or R.sup.3 moieties, or a mixture thereof; each R.sup.5 is C.sub.3 -C.sub.4 alkylene, or the moiety --R.sup.2 --A--R.sup.6 --, where R.sup.6 is a C.sub.1 -C.sub.12 alkylene, alkenylene, arylene or alkarylene moiety; each M is H or a water-soluble cation; each X is H, C.sub.1 -C.sub.4 alkyl or ##STR4## wherein R.sup.7 is C.sub.1 -C.sub.4 alkyl; m and n are numbers such that the moiety --(CH.sub.2 CH.sub.2 O)-- comprises at least about 50% by weight of the moiety --[--(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n --]--, provided that when R.sup.5 is the moiety --R.sup.2 --A--R.sup.6 --, m is 1; each n is at least about 6; u and v are numbers such that the sum of u+v is from about 3 to about 25; w is 0 or at least 1; and when w is at least 1, u, v and w are numbers such that the sum of u+v+w is from about 3 to about 25.

The present invention further relates to detergent compositions, especially for laundry use, which comprise a soil release component having an effective amount of these compounds. These detergent compositions further comprise from about 1 to about 75% by weight of a nonionic, anionic, ampholytic, zwitterionic, or cationic detergent surfactant, or mixture thereof. In addition to these detergent surfactants, the detergent compositions can optionally comprise from 0 to about 60% by weight of a detergent builder.

The compounds of the present invention provide excellent soil release benefits to polyester fabrics during laundering, but without diminishing the clay soil cleaning performance of the detergent composition. These compounds can be used at lower levels in detergent compositions to provide soil release benefits at least equivalent to prior art high molecular weight ethylene terephthalate/PEG terephthalate polyesters. Some of the compounds of the present invention can also be formulated to provide isotropic liquid detergent compositions.

Certain of the soil release compounds of the present invention provide additional through-the-wash static control benefits to laundered fabrics. The compounds of the present invention also provide cleaning benefits in terms of greasy/oily stain removal, as well as whiteness maintenance benefits. In addition, it is expected that the soil release compounds of the present invention will be more biodegradable than prior art ethylene terephthalate/PEG terephthalate soil release polyesters.

FIG. 1 shows a .sup.13 C-NMR spectrum of block polyester compounds of the present invention.

FIG. 2 shows an enlarged view of a portion of the .sup.13 C-NMR spectrum shown in FIG. 1.

The compounds of the present invention have the formula:

In this formula, the moiety --(A--R.sup.1 --A--R.sup.2).sub.u (A--R.sup.3 --A--R.sup.2).sub.v ]A--R.sup.4 --A-- forms the oligomer or polymer backbone of the compounds. It is believed that the structure of the backbone is what is important to the adsorption of the compounds on polyester fabrics during laundering. Groups X--(OCH.sub.2 CH.sub.2).sub.n (OR.sup.5).sub.m ] and --(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n ]X are generally connected at the ends of the oligomer/polymer backbone. It is believed that the soil release properties of the compounds (when absorbed on the fabric) are due to these hydrophilic end groups.

The linking A moieties are essentially ##STR5## moieties, i.e. the compounds of the present invention are polyesters. As used herein, the term "the A moieties are essentially ##STR6## moieties" refers to compounds where the A moieties consist entirely of moieties ##STR7## or are partially substituted with linking moieties such as ##STR8## The degree of partial substitution with these other linking moieties should be such that the soil release properties are not adversely affected to any great extent. Preferably, linking moieties A consist entirely of (i.e., comprise 100%) moieties ##STR9## i.e., each A is either ##STR10##

The R.sup.1 moieties are essentially 1,4-phenylene moieties. As used herein, the term "term R.sup.1 moieties are essentially 1,4-phenylene moieties" refers to compounds where the R.sup.1 moieties consist entirely of 1,4-phenylene moieties, or are partially substituted with other arylene or alkarylene moieties, alkylene moieties, alkenylene moieties, or mixtures thereof. Arylene and alkarylene moieties which can be partially substituted for 1,4-phenylene include 1,3-phenylene, 1,2-phenylene, 1,8-naphthylene, 1,4-naphthylene, 2,2-biphenylene, 4,4'-biphenylene and mixtures thereof. Alkylene and alkenylene moieties which can be partially substituted include ethylene, 1,2-propylene, 1,4-butylene, 1,5-pentylene, 1,6-hexamethylene, 1,7-heptamethylene, 1,8-octamethylene, 1,4-cyclohexylene, and mixtures thereof.

For the R.sup.1 moieties, the degree of partial substitution with moieties other than 1,4-phenylene should be such that the soil release properties of the compound are not adversely affected to any great extent. Generally, the degree of partial substitution which can be tolerated will depend upon the backbone length of the compound, i.e., longer backbones can have greater partial substitution for 1,4-phenylene moieties. Usually, compounds where the R.sup.1 comprise from about 50 to 100% 1,4-phenylene moieties (from 0 to about 50% moieties other than 1,4-phenylene) have adequate soil release activity. For example, polyesters made according to the present invention with a 40:60 mole ratio of isophthalic (1,3-phenylene) to terephthalic (1,4-phenylene) acid have adequate soil release activity. However, because most polyesters used in fiber making comprise ethylene terephthalate units, it is usually desirable to minimize the degree of partial substitution with moieties other than 1,4-phenylene for best soil release activity. Preferably, the R.sup.1 moieties consist entirely of (i.e., comprise 100%) 1,4-phenylene moieties, i.e. each R.sup. 1 moiety is 1,4-phenylene.

The R.sup.2 moieties are essentially ethylene moieties, or substituted ethylene moieties having C.sub.1 -C.sub.4 alkyl or alkoxy substituents. As used herein, the term "the R.sup.2 moieties are essentially ethylene moieties, or substituted ethylene moieties having C.sub.1 -C.sub.4 alkyl or alkoxy substituents" refers to compounds of the present invention where the R.sup.2 moieties consist entirely of ethylene, or substituted ethylene moieties, or are partially substituted with other compatible moieties. Examples of these other moieties include linear C.sub.3 -C.sub.6 alkylene moieties such as 1,3-propylene, 1,4-butylene, 1,5-pentylene or 1,6-hexamethylene, 1,2-cycloalkylene moieties such as 1,2-cyclohexylene, 1,4-cycloalkylene moieties such as 1,4-cyclohexylene and 1,4-dimethylenecyclohexylene, polyoxyalkylated 1,2-hydroxylalkylene such as ##STR11## and oxyalkylene moieties such as --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 -- or --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --.

For the R.sup.2 moities, the degree of partial substitution with these other moieties should be such that the soil release properties of the compounds are not adversely affected to any great extent. Generally, the degree of partial substitution which can be tolerated will depend upon the backbone length of the compound, i.e., longer backbones can have greater partial substitution. Usually, compounds where the R.sup.2 comprise from about 20 to 100% ethylene, or substituted ethylene moieties (from 0 to about 80% other compatible moieties) have adequate soil release activity. For example, for polyesters made according to the present invention with a 75:25 mole ratio of diethylene glycol (--CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --) to ethylene glycol (ethylene) have adequate soil release activity. However, it is desirable to minimize such partial substitution, especially with oxyalkylene moieties, for best soil release activity. (During the making of polyesters according to the present invention, small amounts of these oxyalkylene moieties (as dialkylene glycols) are typically formed from glycols in side reactions and are then incorporated into the polyester). Preferably, R.sup.2 comprises from about 80 to 100% ethylene, or substituted ethylene moieties, and from 0 to about 20% other compatible moieties.

For the R.sup.2 moieties, suitable ethylene or substituted ethylene moieties include ethylene, 1,2-propylene, 1,2-butylene, 1,2-hexylene, 3-methoxy-1,2-propylene and mixtures thereof. Preferably, the R.sup.2 moieties are essentially ethylene moieties, 1,2-propylene moieties or mixtures thereof. Inclusion of a greater percentage of ethylene moieties tends to improve the soil release activity of the compounds. Surprisingly, inclusion of a greater percentage of 1,2-propylene moieties tends to improve the water solubility of the compounds.

For the R.sup.3 moieties, suitable substituted C.sub.2 -C.sub.18 hydrocarbylene moieties can include substituted C.sub.2 -C.sub.12 alkylene, alkenylene, arylene, alkarylene and the like moieties. The substituted alkylene or alkenylene moieties can be linear, branched, or cyclic. Also, the R.sup.3 moieties can be all the same (e.g. all substituted arylene) or a mixture (e.g. a mixture of substituted arylenes and substituted alkylenes). Preferred R.sup.3 moieties are those which are substituted 1,3-phenylene moieties.

The substituted R.sup.3 moieties preferably have only one --SO.sub.3 M, --COOM, --O--(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O.sub.n --X or --A--(R.sup.2 --A--R.sup.4 --A)].sub.w [(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n --X substitutent. M can be H or any compatible water-soluble cation. Suitable water soluble cations include the water soluble alkali metals such as potassium (K.sup.+) and especially sodium (Na.sup.+), as well as ammonium (NH.sub.4.sup.+). Also suitable are substituted ammonium cations having the formula: ##STR12## where R.sup.1 and R.sup.2 are each a C.sub.1 -C.sub.20 hydrocarbyl group (e.g. alkyl, hydroxyalkyl) or together form a cyclic or heterocyclic ring of from 4 to 6 carbon atoms (e.g. piperidine, morpholine); R.sup.3 is a C.sub.1 -C.sub.20 hydrocarbyl group; and R.sup.4 is H (ammonium) or a C.sub.1 -C.sub.20 hydrocarbyl group (quat amine). Typical substituted ammonium cationic groups are those where R.sup.4 is H (ammonium) or C.sub.1 -C.sub.4 alkyl, especially methyl (quat amine); R.sup.1 is C.sub.10 -C.sub.18 alkyl, especially C.sub.12 -C.sub.14 alkyl; and R.sup.2 and R.sup.3 are each C.sub.1 -C.sub.4 alkyl, especially methyl.

The R.sup.3 moieties having --A--(R.sup.2 --A--R.sup.4 A)].sub.w --(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n --X substituents provide branched compounds. R.sup.3 moieties having --A--[(R.sup.2 --A--R.sup.4 --A)--].sub.x --R.sup.2 --A moieties provide crosslinked compounds. Indeed, syntheses used to make the branched compounds typically provide at least some crosslinked compounds.

The moieties --(R.sup.5 O)-- and --(CH.sub.2 CH.sub.2 O)-- of the moieties --(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n -- and --(OCH.sub.2 CH.sub.2).sub.n (OR.sup.5).sub.m -- can be mixed together or preferably form blocks of --(R.sup.5 O)-- and --(CH.sub.2 CH.sub.2 O)-- moieties. Preferably, the blocks of --(R.sup.5 O)-- moieties are located next to the backbone of the compound. When R.sup.5 is the moiety --R.sup.2 --A--R.sup.6 --, m is 1; also, the moiety --R.sup.2 --A--R.sup.6 -- is preferably located next to the backbone of the compound. For R.sup.5, the preferred C.sub.3 -C.sub.4 alkylene is C.sub.3 H.sub.6 (propylene); when R.sup.5 is C.sub.3 -C.sub.4 alkylene, m is preferably from 0 to about 5 and is most preferably 0. R.sup.6 is preferably methylene or 1,4-phenylene. The moiety --(CH.sub.2 CH.sub.2 O)-- preferably comprises at least about 75% by weight of the moiety --(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n -- and most preferably 100% by weight (m is 0). X can be H, C.sub.1 -C.sub.4 alkyl or ##STR13## wherein R.sup.7 is C.sub.1 -C.sub.4 alkyl. X is preferably methyl or ethyl, and most preferably methyl.

The value for each n is at least about 6, but is preferably at least about 10. The value for each n usually ranges from about 12 to about 113. Typically, the value for each n is in the range of from about 12 to about 43.

The backbone moieties --A--R.sup.1 --A--R.sup.2 -- and --A--R.sup.3 --A--R.sup.2 13 can be mixed together or can form blocks of --A--R.sup.1 --A--R.sup.2 -- and --A--R.sup.3 --A--R.sup.2 -- moieties. It has been found that the value of u+v needs to be at least about 3 in order for the compounds of the present invention to have significant soil release activity. The maximum value for u+v is generally determined by the process by which the compound is made, but can range up to about 25, i.e. the compounds of the present invention are oligomers or low molecular weight polymers. By comparison, polyesters used in fiber making typically have a much higher molecular weight, e.g. have from about 50 to about 250 ethylene terephthalate units. Typically, the sum of u+v ranges from about 3 to about 10 for the compounds of the present invention.

Generally, the larger the u+v value, the less soluble is the compound, especially when the R.sup.3 moieties do not have the substituents --COOM or --SO.sub.3 M. Also, as the value for n increases, the value for u+v should be increased so that the compound will deposit better on the fabric during laundering. When the R.sup.3 moieties have the substituent --A--(R.sup.2 --A--R.sup.4 --A)].sub.w [(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n --X (branched compounds) or --A--(R.sup.2 --A--R.sup.4 --A)].sub.w R.sup.2 --A-- (crosslinked compounds), the value for w is typically at least 1 and is determined by the process by which the compound is made. For these branched and crosslinked compounds the value for u+v+w is from about 3 to about 25.

Preferred compounds of the present invention are block polyesters having the formula: ##STR14## wherein the R.sup.1 moieties are all 1,4-phenylene moieties; the R.sup.2 moieties are essentially ethylene moieties, 1,2-propylene moieties or mixtures thereof; the R.sup.3 moieties are all potassium or preferrably sodium 5-sulfo-1,3-phenylene moieties or substituted 1,3-phenylene moieties having the substituent ##STR15## at the 5 position; the R.sup.4 moieties are R.sup.1 or R.sup.3 moieties, or mixtures thereof; each X is ethyl or preferably methyl; each n is from about 12 to about 43; when w is 0, u+v is from about 3 to about 10; when w is at least 1, u+v+w is from about 3 to about 10.

Particularly preferred block polyesters are those where v is 0, i.e. the linear block polyesters. For these most preferred linear block polyesters, u typically ranges from about 3 to about 8, especially for those made from dimethyl terephthalate, ethylene glycol (or 1,2-propylene glycol) and methyl capped polyethylene glycol. The most water soluble of these linear block polyesters are those where u is from about 3 to about 5.

The compounds of the present invention can be prepared by art-recognized methods. Although the following synthesis description is for the preferred block polyesters of the present invention, other versions can be prepared by appropriate variation.

The block polyesters of the present invention are typically formed from: (1) ethylene glycol, 1,2-propylene glycol or a mixture thereof; (2) a polyethylene glycol (PEG) capped at one end with a C.sub.1 -C.sub.4 alkyl group; (3) a dicarboxylic acid (or its diester); and optionally (4) an alkali metal salt of a sulfonated aromatic dicarboxylic acid (or its diester), or if branched polyesters are desired, a polycarboxylic acid (or its ester). The respective amounts of these four components are selected to prepare polyesters having the desired properties in terms of solubility and solid release properties.

The capped PEG used to prepare polyesters of the present invention is typically methyl capped and can be formed by ethoxylation of the respective alcohol with ethylene oxide. Also, methyl capped PEGs are commercially available from Union Carbide under the trade name Methoxy Carbowax and from Aldrich Chemical Company under the name poly(ethylene glycol) methyl ether. These commercial methyl capped PEGs have molecular weights of 350 (n=about 7.5), 550 (n=about 12), 750 (n=about 16 ), 1900 (n=about 43), and 5000 (n=about 113).

Preferably, the only dicarboxylic acid used is terephthalic acid or its diester. However, minor amounts of other aromatic dicarboxylic acids (or their diesters), or aliphatic dicarboxylic acids (or their diesters) can be included to the extent that the soil release properties are substantially maintained. Illustrative examples of other aromatic dicarboxylic acids which can be used include isophthalic acid, phthalic acid, naphthalene dicarboxylic acids, anthracene dicarboxylic acids, biphenyl dicarboxylic acids, oxydibenzoic acids and the like, as well as mixtures of these acids. If aliphatic dicarboxylic acids are included, adipic, glutaric succinic, trimethyladipic, pimelic, azelaic, sebacic, suberic, 1,4-cyclohexane dicarboxylic acid and/or dodecanedioic acids can be used.

Illustrative examples of sulfonated aromatic dicarboxylic acids which can be used to prepare polyesters of the present invention include the alkyl metal salts of benzene-2,5-dicarboxy sulfonate, 2-naphthyl-dicarboxy-benzene sulfonate, 1-naphthyl-dicarboxy-benzene sulfonate, phenyl-dicarboxy benzene sulfonate, 2,6-dimethyl phenyl-3,5-dicarboxy benzene sulfonate and phenyl-3,5-dicarboxy-benzene sulfonate. The preferred sulfonated salt is the 5-sulfoisophthalic acid sodium salt or its diester. If branched polyesters are desired, a minor amount of a polycarboxylic acid (or its diester) selected from trimesic acid, timellitic acid, hemimellitic acid, pyromellitic acid, and mixtures thereof can be used.

The preferred method for preparing block polyesters of the present invention comprises reacting the desired mixture of lower dialkyl esters (methyl, ethyl, propyl or butyl) of the dicarboxylic acid with a mixture of the glycol (ethylene glycol, 1,2-propylene glycol or a mixture thereof) and the capped PEG. The glycol esters and oligomers produced in this ester interchange reaction are then polymerized to the desired degree. The ester interchange reaction can be conducted in accordance with reaction conditions generally used for ester interchange reactions. This ester interchange reaction is usually conducted at temperatures of from 120.degree. to 220.degree. C. in the presence of an esterification catalyst. Alcohol is formed and constantly removed thus forcing the reaction to completion. The temperature and pressure of the reaction are desirably controlled so that glycol does not distill from the reaction mixture. Higher temperatures can be used if the reaction is conducted under pressure.

The catalysts used for the ester interchange reaction are those well known to the art. These catalysts include alkyl and alkaline earth metals, for example lithium, sodium, calcium, and magnesium, as well as transition and Group II B metals, for example antimony, maganese, cobalt, and zinc, usually as the respective oxides, carbonates, or acetates. Typically, antimony trioxide and calcium acetate are used.

The extent of the ester interchange reaction can be monitored by the amount of alcohol liberated or the disappearance of the dialkyl esters of the dibasic acids in the reaction mixture as determined by high performance liquid chromatography (HPLC) or any other suitable method. The ester interchange reaction is desirably taken to more than 90% completion. Greater than 95% completion is preferred in order to decrease the amount of sublimates obtained in the polymerization step.

If desired, stabilizers such as phosphorus and phosphoric acid and esters thereof can be added at the end of the ester interchange step. The purpose of the stabilizer is to inhibit degradation, oxidation, and other side reactions; to destroy the catalytic activity of the ester interchange catalyst; and to prevent precipitation of insoluble metal carboxylates. Typically, stabilizers are not used to make the polyesters of the present invention.

When the ester interchange reaction is complete, the glycol ester products are then polymerized to produce polyesters. The desired degree of polymerization can be determined by HPLC and .sup.13 C-NMR analysis. For commercial processes, the polymerization reaction is usually conducted at temperatures of from about 200.degree. to about 280.degree. C. in the presence of a catalyst. Higher temperatures can be used but tend to produce darker colored products. Illustrative examples of catalysts useful for the polymerization step include antimony trioxide, germanium dioxide, titanium alkoxide, hydrated antimony pentoxide, and ester interchange catalysts such the as salts of zinc, cobalt, and maganese.

Excess glycol and other volatiles liberated during the reaction are removed under vacuum. The reaction is continued until polymerization is nearly complete based on analysis by .sup.13 C-NMR and/or reverse phase HPLC and/or gel phase permeation. In addition to the desired polyesters, the crude composition obtained after synthesis contains starting reactants, as well as intermediate products.

Representative examples of specific block polyester formed according to the present invention are as follows:

A linear block polyester made from dimethyl terephthalate, a methyl capped PEG and ethylene glycol was synthesized as follows:

The following reactants and catalysts were placed in a three necked, 2 liter round bottom flask:

1. poly(ethylene glycol) methyl ether, M.W. 750, Aldrich Chemical Co., 1000 g (1.33 moles)

2. dimethyl terephthalate, Aldrich Chemical Co., 359.9 g (1.85 moles)

3. ethylene glycol, Matheson Coleman Bell (MCB), 140 g (2.26 moles)

4. calcium acetate monohydrate, MCB, 2 g

5. antimony trioxide, Fisher, 2 g

A 0.9 g portion of butylated hydroxytoluene (BHT) was added to the reactants as an antioxidant and the reaction system was then equipped for distillation through a 4 inch, unpacked column. The system was placed under a nitrogen atmosphere and the temperature was raised to 175.degree. C. gradually in about 2 hrs with magnetic stirring once the reaction mixture melted. When methanol began to distill, the temperature was then raised to 205.degree. C. during the next 5 hrs. At this point, about 70% of the theoretical amount of methanol had distilled out. The temperature was then raised to 220.degree. C. and held at this temperature for the next 18 hrs. to give 93% of the theoretical amount of methanol.

The receiving flask was then emptied and the reaction mixture cooled to 130.degree. C. A vacuum was then applied with a steady flow of nitrogen being introduced below the level of the liquid reaction mixture through a fritted glass inlet. The temperature was gradually raised to 200.degree. C. and the vacuum held at 20 mm Hg. After approximately 15 hrs. at 200.degree. C. (under vacuum), the reaction was essentially complete as indicated by .sup.13 C-NMR which showed only trace quantities of residual --CH.sub.2 OH groups. Reverse phase HPLC analysis using a column packed with hexyl capped silica particles and an acetonitrile/water gradient elution showed a sizeable part of the polymer contained 4 or more terephthalate units per molecule. By appropriate variation of reaction conditions, similar polyesters can be prepared by substituting 1,2-propylene glycol for ethylene glycol.

A linear block polyester made from dimethyl terephthalate, sodium dimethyl 5-sulfoisophthalate, ethylene glycol, and methyl capped PEG was synthesized as follows:

Ten grams (0.16 moles) of ethylene glycol and 3.46 g (0.0117 moles) of dimethyl 5-sulfoisophthalate as the sodium salt (Aldrich) were placed in a 100 ml round bottom flask with magnetic stirrer. A 0.26 g portion of antimony trioxide (Fisher), 0.26 g calcium acetate monohydrate (MCB), and 0.11 g BHT were added to the flask. The flask was equipped for short path distillation under an argon atmosphere. The flask was heated in a 200.degree. C. oil bath for 1.25 hrs. after which the reaction mixture had become homogeneous. Then 7.72 g (0.0398 moles) of dimethyl terephthalate (Aldrich) and 22.2 g (0.0117 moles) of poly(ethylene glycol) methyl ether, M.W. 1900 (Aldrich) were added and heating was continued overnight to drive out the methanol. Then the reaction flask was transferred to an Aldrich kugelrohr apparatus where it was heated in a 150.degree. C. air bath while under vacuum (0.1 mm Hg) for about 4 hours to give the desired polyester. Gel phase permeation on Microstyrage.RTM. in tetrahydrofuran (THF) indicated an apparent peak molecular weight of approximately 7100 relative to several polystyrene standards.

A branched block polyester was synthesized as follows:

The following were placed in a 100 ml round bottom flask equipped for magnetic stirring and short path distillation under argon:

1. dimethyl terephthalate (Aldrich), 2.25 g (0.0116 moles)

2. trimethyl trimesate (Aldrich), 0.88 g (0.0035 moles)

3. ethylene glycol (MCB), approximately 1.4 g (approximately 0.023 moles)

4. poly(ethylene glycol) methyl ether M.W. 1900 (Aldrich), 20 g (0.0105 moles)

5. calcium acetate monohydrate (MCB), 0.075 g

6. antimony trioxide (Fisher), 0.075 g

7. BHT (Aldrich), 0.030 g

The reaction flask was heated in a 200.degree. C. oil bath until methanol evolution ceased (approximately 8 hrs). Then the reaction flask was placed in an Aldrich kugelrohr apparatus at 150.degree. C. and under vacuum (0.1 mm Hg) for 4 hours to give the desired branched polyester. Gel permeation chromatography on Microstyrage.RTM. in THF indicated the polyester had a bimodal distribution apparent molecular weights around 12,000 and 29,000 relative to several polystyrene standards, suggesting some crosslinking had occurred.

A linear block polyester made from terephthalic acid, a methyl capped PEG and ethylene glycol was synthesized as follows:

Twenty grams (0.12 moles) of terephthalic acid and 22.4 g (0.36 moles) of ethylene glycol (MCB) were heated together at 220.degree.-240.degree. C. in a short path distillation apparatus. Ethylene glycol which distilled out with the water was periodically replaced. After 13 hrs. of heating, the reaction mixture was cooled and the following were added:

1. poly(ethylene glycol) methyl ether, M.W. 750 (Aldrich), 102.6 g (0.137 moles)

2. antimony trioxide (Fisher), 0.50 g

3. calcium acetate monohydrate (MCB), 0.50 g

4. BHT (Aldrich), 0.20 g

The reaction system was gradually heated to 240.degree. C. with little distillate in evidence. A vacuum was then applied and the temperature was held at 240.degree.-250.degree. C. for 6 hrs. to give the desired polyester. Gel permeation chromatography indicated the apparent peak molecular weight was approximately 2200 relative to several polystyrene standards.

A method for determining the degree of polymerization of the polyesters of the present invention involves: (1) alcohol fractionation of the crude polyester composition obtained after synthesis; (2) high performance liquid chromatographic (HPLC) separation of the methanol soluble fraction to yield additional fractions; and (3) .sup.13 C-NMR analysis to determine backbone length (i.e. value for u) of the polyesters present in each of the various HPLC fractions. While this method is described with respect to polyesters made from terephthalic acid and ethylene glycol, it should be suitable, with appropriate modifications, for analyzing other polyester versions of the present invention.

A. Alcohol Fractionation

The crude polyester composition obtained after synthesis is successively extracted with 2-propanol, ethanol and methanol to obtain a methanol soluble fraction which contains more of the desired active polyesters. One such fractionation was carried out as follows:

A 569 g portion of a crude polyester composition made similar to Example 1 was melted and poured into a 4 liter Erlenmeyer flask. After the crude polyester had cooled, 2000 ml of 2-propanol was added. This mixture was stirred for about 60 hrs. The dispersion was allowed to settle and the clear supernatant was decanted. The residue was stirred again with another 2000 ml of 2-propanol. All remaining lumps of polyester were broken up. After stirring 2 hrs, the solids were allowed to settle and the clear supernatant was decanted. Then a third 2000 ml portion of 2-propanol was added to the precipitate and this mixture was stirred overnight. The resulting dispersion was allowed to settle. The supernatant was decanted and the residue was centrifuged to remove as much 2-propanol as possible. The residue was then taken up in 3000 ml of 3A denatured ethanol. This dispersion was stirred overnight at room temperature. It was then centrifuged to give a slightly cloudy supernatant which was decanted. The precipitate was dispersed in 3250 ml of methanol by stirring overnight at room temperature. Centrifugation gave a cloudy supernatant. This supernatant containing the methanol soluble polyesters was decanted and the methanol was removed on a rotary evaporator followed by 15 minutes on a Aldrich kugelrohr at 110.degree. C. This yielded 98.5 grams of a methanol soluble fraction (17.5%) of polyesters.

B. Semi-Preparative HPLC Fractionation

The crude polyester compositions of the present invention, such as those of Example 1, can be separated into various, identifiable fractions by HPLC. Typically, a chromatogram for identifying the various fractions of the crude polyester composition is developed using the following HPLC conditions:

1. Equipment:

a. Waters WISP 710B automatic injector

b. Two Laboratory Data Control (LDC) Model III pumps

c. LDC Gradient Master

d. LDC Spectromonitor III detector

e. Waters Data Module Model 730 recorder

2. Solvent Program:

a. initial conditions: 34% CH.sub.3 CN/66% H.sub.2 O

b. final conditions: 60% CH.sub.3 CN/40% H.sub.2 O

c. gradient time: 20 min., then 15 min. hold at final conditions

d. linear gradient

e. flow rate: 1 ml/min

3. Column: 4.6 mm.times.25 cm. Phase Separations' Spherisorb 5 micron hexyl

4. Injection Volume: 10-50 microl.

5. Detection: 254 nm uv at 0.1-0.3 Absorbance Units Full Scale (AUFS)

6. Sample Preparation: 1.0-4.0 mg/ml predissolved in 34% CH.sub.3 CN/66% H.sub.2 O

Some of the peaks present in this crude chromatogram represent fractions of the polyester composition which contain little or none of the active soil release polyesters. Accordingly, a semi-preparative HPLC procedure is used to obtain fractions containing more of the active polyesters for subsequent .sup.13 C-NMR analysis. This semi-preparative method involves separating the previously obtained methanol soluble fraction by HPLC into additional fractions using the following conditions:

1. Equipment:

a. Rheodyne 7126 valve manual injector

b. Two Perkin/Elmer System III pumps

c. Micromeritics 788 detector

d. Sargent Welch strip chart recorder

2. Solvent Program:

a. initial conditions: 38% CH.sub.3 CN/62% H.sub.2 O

b. step 1: final conditions, 55% Ch.sub.3 CN/45% H.sub.2 O, linear gradient, 22.7 min.

c. step 2: 55% CH.sub.3 CN/45% H.sub.2 O, hold for 7 min.

d. step 3: final conditions, 75% CH.sub.3 CN/25% H.sub.2 O, linear gradient, 23.5 min.

e. step 4: 75% CH.sub.3 CN/25% H.sub.2 O, hold for 7 min.

f. flow rate: 20 ml/min.

3. Column: 20 mm.times.25 cm. Phase Separations' Spherisorb 5 micron hexyl

4. Injection Volume: 3.8 ml.

5. Detection: 254 nm uv at 0.6-2.56 AUFS

6. Sample Preparation: saturated solution in 38% CH.sub.3 CN/62% H.sub.2 O

The fractions obtained by semi-preparative HPLC are compared to those of the chromatogram for the crude composition to identify the various fractions. A representatiave semi-preparative HPLC fractionation of a polyester composition made similar to Example 1 is shown in the following Table:

C. .sup.13 C-NMR Analysis

The various fractions obtained by semi-preparative HPLC can be analyzed by .sup.13 C-NMR to determine the degree of polymerization of the polyesters present in each fraction. FIG. 1 represents a .sup.13 C-NMR spectrum of a polyester composition made similar to Example 1. FIG. 2 represents an expanded view of a portion of the spectrum shown in FIG. 1.

Assignment of carbon resonances are made by comparison to model compounds and/or spiking experiments. .sup.13 C-NMR parameters are chosen to give quantitative information, i.e., peak areas can be used to determine relative levels of intermediate compounds and polyesters present in the semi-preparative HPLC fraction.

Chemical shift assignments of several key carbon resonances are shown in the following Table:

There are two ways to express the average degree of polymerization of the polyesters present in each fraction. The first is a ratio of areas (determined by .sup.13 C-NMR) of the ethylene units (S) present in the polyester backbone relative to the methyl cap (M) of the PEG. This ratio S/M is equal to Area 3 (see FIG. 1) divided by Area 1 (see FIG. 1), which is then multiplied by 1/2. The second is a ratio of the average number of aromatic terephthalate units (A) present in the backbone relative to M. This second ratio A/M equals Area 2 (See FIG. 1) divided by Area 1, which is then multiplied by 1/4.

A more useful quantity is obtained by adjusting the observed A/M ratio for the contribution of monoterephthalate polyesters, i.e. where u is 0.

The adjusted A/M value equals ##EQU1## wherein f.sub.1 is the mole fraction of monoterephthalate polyester (area f.sub.1 /Total Area, See FIG. 2). Another important value is f.sub.4 which represents the mole fraction of terephthalate present in polyesters having 3 or more terephthalate units (Area f.sub.4 /Total Area, see FIG. 2).

The results of .sup.13 C-NMR analysis of the fractions obtained by semi-preparative HPLC of a polyester composition made similar to Example 1 is shown in the following Table:

The compounds of the present invention are particularly useful in detergent compositions to provide soil release properties. These compositions can be used as laundry detergents, laundry additives, and laundry pre-treatments.

The detergent compositions of the present invention comprise a soil release component which contains an effective amount of the soil release compounds previously defined. What is an "effective amount" will depend upon the particular soil release compounds used, the particular type of detergent formulation (liquid, granular, etc.) and the benefits desired. Usually, the soil release compounds are effective when included in an amount from about 0.01 to about 10% by weight of the composition. In terms of soil release benefits, preferred detergent compositions can comprise from about 0.1 to about 5% by weight of the soil release compounds, but typically comprise from about 0.3 to about 3% by weight of these compounds.

For granular detergent formulations, the soil release component typically comprises the soil release compounds, plus any protective enrobing material. In making granular detergent formulations, the soil release compounds could be exposed to highly alkaline materials such as NaOH and KOH. The soil release compounds, in particular those having shorter backbones, can be degraded by alkaline environments, especially those above a pH of about 8.5. Accordingly, the soil release compounds are preferably enrobed in a material which protects them from the alkaline environment of a granular detergent formulation yet permits the soil release compounds to be dispersed in the laundering operation.

Suitable enrobing materials include the nonionic surfactants, polyethylene glycols (PEG), fatty acids, fatty acid esters of alcohols, diols and polyols, anionic surfactants, film forming polymers and mixtures of these materials. Examples of suitable nonionic surfactant enrobing materials are described in the Detergent Surfactant section of this application. Examples of suitable PEG enrobing materials are those having an average M.W. of from about 2,000 to 15,000, preferably from about 3,000 to about 10,000 and most preferably from about 4,000 to about 8,000.Examples of suitable fatty acid enrobing materials are the higher fatty acids having from 12 to 18 carbon atoms. Examples of suitable fatty acid ester enrobing materials include the sorbitan fatty acid esters (e.g. sorbitan monolaurate). Other examples of suitable enrobing materials, including anionic surfactants and film forming polymers, are disclosed in U.S. Pat. No. 4,486,327 to Murphy et al., issued Dec. 4, 1984, which is incorporated by reference. The soil release compounds can be enrobed according to the methods disclosed in this Murphy et al. patent.

For liquid detergent formulations, the soil release component can be comprised entirely of soil release compounds or can further include a water-soluble organic solvent or an hydrotrope to aid in dissolving the soil release compounds. Suitable organic solvents are usually aromatic and can include ethyl benzoate, phenoxyethanol, methyl-o-toluate, 2-methoxybenzyl alcohol and pyrrolidone. Suitable hydrotropes include the methyl capped PEGs and shorter backbone block polyesters, i.e. where u is 0 to 2. While these short backbone block polyesters do not have any significant soil release activity, they are water-soluble. Accordingly, these short backbone polyesters function as hydrotropes for the longer backbone, water-insoluble polyesters which have soil release activity.

The amount, or even need for, organic solvents or hydrotropes to prepare liquid detergent formulations containing the soil release compounds of the present invention will depend upon the compounds used, especially what fraction thereof is water-soluble, the ingredients present in the laundry detergent system, and whether an isotropic, homogeneous liquid is desired. For isotropic liquid detergent formulations, the soil release compounds need to be dissolved as much as possible which sometimes requires the use of organic solvents or hydrotropes. Also, it has been found that dissolving the compounds in the liquid detergent formulations makes them more effective as soil release agents.

Besides organic solvents or hydrotropes, greater amounts of water-soluble soil release compounds can be included in the soil release component to aid in the preparation of isotropic liquid detergent formulations. For example, soil release polyesters with backbones having from about 3 to about 5 (u=about 3 to about 5) ethylene terephthalate units and having a methyl capped PEG of molecular weight of 750 (n=about 16) at each end are water-soluble. In addition, soil release polyesters prepared from dimethyl terephthalate, ethylene glycol and methyl capped PEGs typically contain a substantial fraction of water-soluble polyesters (both active and inactive types) which aid in dissolving water-insoluble soil release polyesters in the liquid detergent formulation. Partial or total substitution of 1,2-propylene glycol for ethylene glycol can also be used to increase the solubility of the soil release polyesters. The more water-soluble 1,2-propylene glycol based soil release polyesters are particularly useful in making isotropic liquid detergent formulations which have a large number of ingredients and low water content.

The amount of detergent surfactant included in the detergent compositions of the present invention can vary from about 1 to about 75% by weight of the composition depending upon the detergent surfactant(s) used, the type of composition to be formulated (e.g. granular, liquid) and the effects desired. Preferably, the detergent surfactant(s) comprises from about 10 to about 50% by weight of the composition, and most preferably from about 15 to about 40% by weight. The detergent surfactant can be nonionic, anionic, ampholytic, zwitterionic, cationic, or a mixture thereof:

A. Nonionic Surfactants

Suitable nonionic surfactants for use in detergent compositions of the present invention are generally disclosed in U.S. Pat. No. 3,929,678 to Laughlin et al., issued Dec. 30, 1975 at column 13, line 14 through column 16, line 6 (herein incorporated by reference). Classes of nonionic surfactants included are:

1. The polyethylene oxide condensates of alkyl phenols. These compounds include the condensation products of alkyl phenols having an alkyl group containing from about 6 to 12 carbon atoms in either a straight chain or branched chain configuration with ethylene oxide, the ethylene oxide being present in an amount equal to 5 to 25 moles of ethylene oxide per mole of alkyl phenol. The alkyl substituent in such compounds can be derived, for example, from polymerized propylene, diisobutylene, and the like. Examples of compounds of this type include nonyl phenol condensed with about 9.5 moles of ethylene oxide per mole of nonyl phenol; dodecylphenol condensed with about 12 moles of ethylene oxide per mole of phenol; dinonyl phenol condensed with about 15 moles of ethylene oxide per mole of phenol; and diisooctyl phenol condensed with about 15 moles of ethylene oxide per mole of phenol. Commercially available nonionic surfactants of this type include Igepal CO-630, marketed by the GAF Corporation, and Triton X-45, X-114, X-100, and X-102, all marketed by the Rohm & Haas Company.

2. The condensation products of aliphatic alcohols with from about 1 to about 24 moles of ethylene oxide. The alkyl chain of the aliphatic alcohol can either be straight or branched, primary or secondary, and generally contain from about 8 to about 22 carbon atoms. Examples of such ethoxylated alcohols include the condensation product of myristyl alcohol condensed with about 10 moles of ethylene oxide per mole of alcohol; and the condensation product of about 9 moles of ethylene oxide with coconut alcohol (a mixture of fatty alcohols with alkyl chains varying in length from 10 to 14 carbon atoms). Examples of commercially available nonionic surfactants of this type include Tergitol 15-S-9, marketed by Union Carbide Corporation, Neodol 45-9, Neodol 23-6.5, Neodol 45-7, and Neodol 45-4, marketed by Shell Chemical Company, and Kyro EOB, marketed by The Procter & Gamble Company.

3. The condensation product of ethylene oxide with a hydrophobic based formed by the condensation of propylene oxide with propylene glycol. The hydrophobic portion of these compounds has a molecular weight of from about 1500 to 1800 and exhibits water insolubility. The addition of polyoxyethylene moieties to this hydrophobic portion tends to increase the water solubility of the molecule as a whole, and the liquid character of the product is retained up to the point where the polyoxyethylene content is about 50% of the total weight of the condensation product, which corresponds to condensation with up to about 40 moles of ethylene oxide. Examples of compounds of this type include certain of the commercially available Pluronic surfactants, marketed by Wyandotte Chemical Corporation.

4. The condensation products of ethylene oxide with the product resulting from the reaction of propylene oxide and ethylenediamine. The hydrophobic moiety of these products consists of the reaction product of ethylenediamine and excess propylene oxide, the moiety having a molecular weight of from about 2500 to about 3000. This hydrophobic moiety is condensed with ethylene oxide to the extent that the condensation product contains from about 40% to about 80% by weight of polyoxyethylene and has a molecular weight of from about 5,000 to about 11,000. Examples of this type of nonionic surfactant include certain of the commercially available Tetronic compounds, marketed by Wyandotte Chemical Corporation.

5. Semi-polar nonionic detergent surfactants which include water-soluble amine oxides containing one alkyl moiety of from about 10 to 18 carbon atoms and 2 moieties selected from the group consisting of alkyl groups and hydroxyalkyl groups containing from 1 to about 3 carbon atoms; water-soluble phosphine oxides containing one alkyl moiety of from about 10 to 18 carbon atoms and 2 moieties selected from the group consisting of alkyl groups and hydroxyalkyl groups containing from about 1 to 3 carbon atoms; and water-soluble sulfoxides containing one alkyl moiety of from about 10 to 18 carbon atoms and a moiety selected from the group consisting of alkyl and hydroxyalkyl moieties of from about 1 to 3 carbon atoms.

Preferred semi-polar nonionic detergent surfactants are the amine oxide detergent surfactants having the formula ##STR16## wherein R.sup.3 is an alkyl, hydroxyalkyl, or alkyl phenyl group or mixtures thereof containing from about 8 to about 22 carbon atoms; R.sup.4 is an alkylene or hydroxyalkylene group containing from 2 to 3 carbon atoms or mixtures thereof; x is from 0 to about 3; and each R.sup.5 is an alkyl or hydroxyalkyl group containing from 1 to about 3 carbon atoms or a polyethylene oxide group containing from one to about 3 ethylene oxide groups. The R.sup.5 groups can be attached to each other, e.g., through an oxygen or nitrogen atom to form a ring structure.

Preferred amine oxide detergent surfactants are C.sub.10 -C.sub.18 alkyl dimethyl amine oxide and C.sub.8 -C.sub.12 alkoxy ethyl dihydroxy ethyl amine oxide.

6. Alkylpolysaccharides disclosed in European patent application No. 70,074 to Ramon A. Llenado, published Jan. 19, 1983, having a hydrophobic group containing from about 6 to about 30 carbon atoms, preferably from about 10 to about 16 carbon atoms and a polysaccharide, e.g., a polyglycoside, hydrophilic group containing from about 11/2 to about 10, preferably from about 11/2 to about 3, most preferably from about 1.6 to about 2.7 saccharide units. Any reducing saccharide containing 5 or 6 carbon atoms can be used, e.g. glucose, galactose and galactosyl moieties can be substituted for the glucosyl moieties. (Optionally the hydrophobic group is attached at the 2, 3, 4, etc. positions thus giving a glucose or galactose as opposed to a glucoside or galactoside.) The intersaccharide bonds can be, e.g., between the one position of the additional saccharide units and the 2-, 3-, 4-, and/or 6 positions on the preceding saccharide units.

Optionally, and less desirably, there can be a polyalkyleneoxide chain joining the hydrophobic moiety and the polysaccharide moiety. The preferred alkyleneoxide is ethylene oxide. Typical hydrophobic groups include alkyl groups, either saturated or unsaturated, branched or unbranched containing from about 8 to about 18, preferably from about 10 to about 16, carbon atoms. Preferably, the alkyl group is a straight chain saturated alkyl group. The alkyl group can contain up to 3 hydroxy groups and/or the polyalkyleneoxide chain can contain up to about 10, preferably less than 5, most preferably 0, alkyleneoxide moieties. Suitable alkyl polysaccharides are octyl, nonyldecyl, undecyldodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl, di-, tri-, tetra-, penta-, and hexaglucosides, galactosides, lactosides, glucoses, fructosides, fructoses, and/or galactoses. Suitable mixtures include coconut alkyl, di-, tri-, tetra-, and pentaglucosides and tallow alkyl tetra-, penta-, and hexaglucosides.

The preferred alkylpolyglycosides have the formula

wherein R.sup.2 is selected from the group consisting of alkyl, alkylphenyl, hydroxyalkyl, hydroxyalkylphenyl, and mixtures thereof in which the alkyl groups contain from about 10 to about 18, preferably from about 12 to about 14, carbon atoms; n is 2 or 3, preferably 2; t is from 0 to about 10, preferably 0; and x is from 11/2 to about 10, preferably from about 11/2 to about 3, most preferably from about 1.6 to about 2.7. The glycosyl is preferably derived from glucose. To prepare these compounds, the alcohol or alkylpolyethoxy alcohol is formed first and then reacted with glucose, or a source of glucose, to form the glucoside (attachment at the 1-position). The additional glycosyl units can then be attached between their 1-position and the preceding glycosyl units 2-, 3-, 4- and/or 6-position, preferably predominately the 2-position.

7. Fatty acid amide detergent surfactants having the formula: ##STR17## wherein R.sup.6 is an alkyl group containing from about 7 to about 21 (preferably from about 9 to about 17) carbon atoms and each R.sup.7 is selected from the group consisting of hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 hydroxyalkyl, and --(C.sub.2 H.sub.4 O).sub.x H where x varies from about 1 to about 3.

Preferred amides are C.sub.8 -C.sub.20 ammonia amides, monoethanolamides, diethanolamides, and isopropanol amides.

B. Anionic Surfactants

Anionic surfactants suitable in detergent compositions of the present invention are generally disclosed in U.S. Pat. No. 3,929,678 to Laughlin et al., issued Dec. 30, 1975 at column 23, line 58 through column 29, line 23 (herein incorporated by reference). Classes of anionic surfactants included are:

1. Ordinary alkali metal soaps such as the sodium, potassium, ammonium and alkylolammonium salts of higher fatty acids containing from about 24 carbon atoms, preferably from about 10 to about 20 carbon atoms.

2. Water-soluble salts, preferably the alkali metal, ammonium and alkylolammonium salts, of organic sulfuric reaction products having in their molecular structure an alkyl group containing from about 10 to about 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included in the term "alkyl" is the alkyl portion of acyl groups.)

Examples of this group of anionic surfactants are the sodium and potassium alkyl sulfates, especially those obtained by sulfating the higher alcohols (C.sub.8 -C.sub.18 carbon atoms) such as those produced by reducing the glycerides of tallow or coconut oil; and the sodium and potassium alkylbenzene sulfonates in which the alkyl group contains from about 9 to about 15 carbon atoms, in straight chain or branched chain configuration, e.g., those of the type described in U.S. Pat. Nos. 2,220,099 and 2,477,383. Especially valuable are linear straight chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to 13, abbreviated as C.sub.11 -C.sub.13 LAS.

Preferred anionic surfactants of this type are the alkyl polyethoxylate sulfates, particularly those in which the alkyl group contains from about 10 to about 22, preferably from about 12 to about 18 carbon atoms, and wherein the polyethoxylate chain contains from about 1 to about 15 ethoxylate moieties preferably from about 1 to about 3 ethoxylate moieties. These anionic detergent surfactants are particularly desirable for formulating heavy-duty liquid laundry detergent compositions.

Other anionic surfactants of this type include sodium alkyl glyceryl ether sulfonates, especially those ethers of higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulfonates and sulfates; sodium or potassium salts of alkyl phenol ethylene oxide ether sulfates containing from about 1 to about 10 units of ethylene oxide per molecule and wherein the alkyl groups contain from about 8 to about 12 carbon atoms; and sodium or potassium salts of alkyl ethylene oxide ether sulfates containing about 1 to about 10 units of ethylene oxide per molecule and wherein the alkyl group contains from about 10 to about 20 carbon atoms.

Also included are water-soluble salts of esters of alpha-sulfonated fatty acids containing from about 6 to 20 carbon atoms in the fatty acid group and from about 1 to 10 carbon atoms in the ester group; water-soluble salts of 2-acyloxy-alkane-1-sulfonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkane moiety; alkyl ether sulfates containing from about 10 to 20 carbon atoms in the alkyl group and from about 1 to 30 moles of ethylene oxide; water-soluble salts of olefin sulfonates containing from about 12 to 24 carbon atoms; and beta-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety.

3. Anionic phosphate surfactants.

4. N-alkyl substituted succinamates.

Ampholytic surfactants can be broadly described as aliphatic derivatives of secondary or tertiary amines, or aliphatic derivatives of heterocyclic secondary and tertiary amines in which the aliphatic radical can be straight chain or branched and wherein one of the aliphatic substituents contains from about 8 to 18 carbon atoms and at least one contains an anionic water-solubilizing group, e.g. carboxy, sulfonate, sulfate. See U.S. Pat. No. 3,929,678 to Laughlin et al., issued Dec. 30, 1975 at column 19, lines 18-35 (herein incorporated by reference) for examples of ampholytic surfactants.

D. Zwitterionic Surfactants

Zwitterionic surfactants can be broadly described as derivatives of secondary and tertiary amines, derivatives of heterocyclic secondary and tertiary amines, or derivatives of quaternary ammonium, quanternary phosphonium or tertiary sulfonium compounds. See U.S. Pat. No. 3,929,678 to Laughlin et al., issued Dec. 30, 1975 at column 19, line 38 through column 22, line 48 (herein incorporated by reference) for examples of zwitterionic surfactants.

E. Cationic Surfactants

Cationic surfactants can also be included in detergent compositions of the present invention. Suitable cationic surfactants include the quaternary ammonium surfactants having the formula:

wherein R.sup.2 is an alkyl or alkyl benzyl group having from about 8 to about 18 carbon atoms in the alkyl chain; each R.sup.3 is selected from the group consisting of --CH.sub.2 CH.sub.2 --, --CH.sub.2 CH(CH.sub.3)--, --CH.sub.2 CH(CH.sub.2 OH)--, --CH.sub.2 CH.sub.2 CH.sub.2 --, and mixtures thereof; each R.sup.4 is selected from the group consisting of C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 hydroxyalkyl, benzyl, ring structures formed by joining the two R.sup.4 groups, --CH.sub.2 CHOHCHOHCOR.sup.6 CHOHCH.sub.2 OH wherein R.sup.6 is any hexose or hexose polymer having a molecular weight less than about 1000, and hydrogen when y is not 0; R.sup.5 is the same as R.sup.4 or is an alkyl chain wherein the total number of carbon atoms of R.sup.2 plus R.sup.5 is not more than about 18; each y is from 0 to 10 and the sum of the y values is from 0 to about 15; and X is any compatible anion.

Preferred of the above are the alkyl quaternary ammonium surfactants, especially the mono-long chain alkyl surfactants described in the above formula when R.sup.5 is selected from the same groups as R.sup.4. The most preferred quaternary ammonium surfactants are the chloride, bromide and methylsulfate C.sub.8 -C.sub.16 alkyl trimethylammonium salts, C.sub.8 -C.sub.16 alkyl di(hydroxyethyl)methylammonium salts, the C.sub.8 -C.sub.16 alkyl hydroxyethyldimethylammonium salts, and C.sub.8 -C.sub.16 alkyloxypropyl trimethylammonium salts. Of the above, decyl trimethylammonium methylsulfate, lauryl trimethylammonium chloride, myristyl trimethylammonium bromide and coconut trimethylammonium chloride and methylsulfate are particularly preferred.

Other useful cationic surfactants are disclosed in U.S. Pat. No. 4,259,217 to Murphy, issued Mar. 31, 1981, herein incorporated by reference.

Detergent compositions of the present invention can optionally comprise inorganic or organic detergent builders to assist in mineral hardness control. When included, these builders typically comprise up to about 60% by weight of the detergent composition. Built liquid formulations preferably comprise from about 1 to about 25% by weight detergent builder, most preferably from about 3 to about 20% by weight, while built granular formulations preferably comprise from about 5 to about 50% by weight detergent builder, most preferably from about 10 to about 30% by weight.

Suitable detergent builders include crystalline aluminosilicate ion exchange materials having the formula:

wherein z and y are at least about 6, the mole ratio of z to y is from about 1.0 to about 0.5; and x is from about 10 to about 264. Amorphous hydrated aluminosilicate materials useful herein have the empirical formula

wherein M is sodium, potassium, ammonium or substituted ammonium, z is from about 0.5 to about 2; and y is 1; this material having a magnesium ion exchange capacity of at least about 50 milligram equivalents of CaCO.sub.3 hardness per gram of anhydrous aluminosilicate.

The aluminosilicate ion exchange builder materials are in hydrated form and contain from about 10% to about 28% of water by weight if crystalline, and potentially even higher amounts of water if amorphous. Highly preferred crystalline aluminosilicate ion exchange materials contain from about 18% to about 22% water in their crystal matrix. The preferred crystalline aluminosilicate ion exchange materials are further characterized by a particle size diameter of from about 0.1 micron to about 10 microns. Amorphous materials are often smaller, e.g., down to less than about 0.01 micron. More preferred ion exchange materials have a particle size diameter of from about 0.2 micron to about 4 microns. The term "particle size diameter" represents the average particle size diameter of a given ion exchange material as determined by conventional analytical techniques such as, for example, microscopic determination utilizing a scanning electron microscope. The crystalline aluminosilicate ion exchange materials are usually further characterized by their calcium ion exchange capacity, which is at least about 200 mg. equivalent of CaCO.sub.3 water hardness/g. of aluminosilicate, calculated on an anhydrous basis, and which generally is in the range of from about 300 mg. eq./g. to about 352 mg. eq./g. The aluminosilicate ion exchange materials are still further characterized by their calcium ion exchange rate which is at least about 2 grains Ca.sup.++ /gallon/minute/gram/gallon of aluminosilicate (anhydrous basis), and generally lies within the range of from about 2 grains/gallon/minute/gram/gallon to about 6 grains/gallon/minute/gram/gallon, based on calcium ion hardness. Optimum aluminosilicates for builder purposes exhibit a calcium ion exchange rate of at least about 4 grains/gallon/minute/gram/gallon.

The amorphous aluminosilicate ion exchange materials usually have a Mg.sup.++ exchange capacity of at least about 50 mg. eq. CaCO.sub.3 /g. (12 mg. Mg.sup.++ /g.) and a Mg.sup.++ exchange rate of at least about 1 grain/gallon/minute/gram/gallon. Amorphous materials do not exhibit an observable diffraction pattern when examined by Cu radiation (1.54 Angstrom Units).

Useful aluminosilicate ion exchange materials are commercially available. These aluminosilicates can be crystalline or amorphous in structure and can be naturally-occurring aluminosilicates or synthetically derived. A method for producing aluminosilicate ion exchange materials is disclosed in U.S. Pat. No. 3,985,669 to Krummel, et al. issued Oct. 12, 1976 (herein incorporated by reference). Preferred synthetic crystalline aluminosilicate ion exchange materials useful herein are available under the designations Zeolite A, Zeolite P (B), and Zeolite X. In an especially preferred embodiment, the crystalline aluminosilicate ion exchange material has the formula

wherein x is from about 20 to about 30, especially about 27.

Other examples of detergency builders include the various water-soluble, alkali metal, ammonium or substituted ammonium phosphates, polyphosphates, phosphonates, polyphosphonates, carbonates, silicates, borates, polyhydroxysulfonates, polyacetates, carboxylates, and polycarboxylates. Preferred are the alkali metal, especially sodium, salts of the above.

Specific examples of inorganic phosphate builders are sodium and potassium tripolyphosphate, pyrophosphate, polymeric metaphate having a degree of polymerization of from about 6 to 21, and orthophosphate. Examples of polyphosphonate builders are the sodium and potassium salts of ethylene-1,1-diphosphonic acid, the sodium and potassium salts of ethane 1-hydroxy-1,1-diphosphonic acid and the sodium and potassium salts of ethane, 1,1,2-triphosphonic acid. Other phosphorus builder compounds are disclosed in U.S. Pat. Nos. 3,159,581; 3,213,030; 3,422,021; 3,422,137; 3,400,176 and 3,400,148 (all herein incorporated by reference).

Examples of nonphosphorus, inorganic builders are sodium and potassium carbonate, bicarbonate, sesquicarbonate, tetraborate decahydrate, and silicate having a mole ratio of SiO.sub.2 to alkali metal oxide of from about 0.5 to about 4.0, preferably from about 1.0 to about 2.4.

Useful water-soluble, nonphosphorus organic builders include the various alkali metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates and polyhydroxysulfonates. Examples of polyacetate and polycarboxylate builders are the sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediamine tetraacetic acid, nitrilotriacetic acid, oxydisuccinic acid, mellitic acid, benzene polycarboxylic acids, citric acid, and 2-hydroxyethyl ethylenediamine triacetic acid.

Highly preferred polycarboxylate builders are disclosed in U.S. Pat. No. 3,308,067 to Diehl, issued Mar. 7, 1967 (herein incorporated by reference). Such materials include the water-soluble salts of homo- and copolymers of aliphatic carboxylic acids such as maleic acid, itaconic acid, mesaconic acid, fumaric acid, aconitic acid, citraconic acid and methylenemalonic acid.

Other builders include the carboxylated carbohydrates disclosed in U.S. Pat. No. 3,723,322 to Diehl, issued Mar. 28, 1973 (herein incorporated by reference).

Other useful builders are sodium and potassium carboxymethyloxymalonate, carboxymethyloxysuccinate, cis-cyclohexanehexacarboxylate, cis-cyclopentanetetracarboxylate phloroglucinol trisulfonate, water-soluble polyacrylates (having molecular weights of from about 2,000 to about 200,000 for example), and the copolymers of maleic anhydride with vinyl methyl ether or ethylene.

Other suitable polycarboxylates are the polyacetal carboxylates disclosed in U.S. Pat. No. 4,144,226, to Crutchfield et al. issued Mar. 13, 1979, and U.S. Pat. No. 4,246,495, to Crutchfield et al., issued Mar. 27, 1979 (both herein incorporated by reference). These polyacetal carboxylates can be prepared by bringing together under polymerization conditions an ester of glyoxylic acid and a polymerization initiator. The resulting polyacetal carboxylate ester is then attached to chemically stable end groups to stabilize the polyacetal carboxylate against rapid depolymerization in alkaline solution, converted to the corresponding salt, and added to a surfactant.

Laundry detergent compositions of the present invention desirably include a clay soil removal and/or anti-redeposition agent. These clay soil removal/anti-redeposition agents are usually included at from about 0.1 to about 10% by weight of the composition. In terms of the benefits achieved, preferred detergent compositions can comprise from about 0.5 to about 5% by weight of these agents. Typically, these preferred compositions comprise from about 1 to about 3% by weight of these agents.

One group of preferred clay soil removal/anti-redeposition agents are the ethoxylated amines disclosed in European patent application 112,593 to James M. Vander Meer, published July 4, 1984, herein incorporated by reference. These ethoxylated amines are selected from the group consisting of:

(1) ethoxylated monoamines having the formula:

(2) ethoxylated diamines having the formula: ##STR18##

(3) ethoxylated polyamines having the formula: ##STR19##

(4) ethoxylated amine polymers having the general formula: ##STR20## and

(5) mixtures thereof; wherein A.sup.1 is ##STR21## R is H or C.sub.1 -C.sub.4 alkyl or hydroxyalkyl; R.sup.1 is C.sub.2 -C.sub.12 alkylene, hydroxyalkylene, alkenylene, arylene or alkarylene, or a C.sub.2 -C.sub.3 oxyalkylene moiety having from 2 to about 20 oxyalkylene units provided that no O-N bonds are formed; each R.sup.2 is C.sub.1 -C.sub.4 alkyl or hydroxyalkyl, the moiety --L--X, or two R.sup.2 together form the moiety --(CH.sub.2).sub.r --A.sup.2 --(CH.sub.2).sub.s --, wherein A.sup.2 is --O-- or --CH.sub.2 --, r is 1 or 2, s is 1 or 2, and r+s is 3 or 4; X is a nonionic group, an anionic group or mixture thereof; R.sup.3 is a substituted C.sub.3 -C.sub.12 alkyl, hydroxyalkyl, alkenyl, aryl, or alkaryl group having p substitution sites; R.sup.4 is C.sub.1 -C.sub.12 alkylene, hydroxyalkylene, alkenylene, arylene or alkarylene, or a C.sub. 2 -C.sub.3 oxyalkylene moiety having from 2 to about 20 oxyalkylene units provided that no O-O or O-N bonds are formed; L is a hydrophilic chain which contains the polyoxyalkylene moiety --(R.sup.5 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n ], wherein R.sup.5 is C.sub.3 -C.sub.4 alkylene or hydroxyalkylene and m and n are numbers such that the moiety --(CH.sub.2 CH.sub.2 O)-- comprises at least about 50% by weight of said polyoxyalkylene moiety; for said monoamines, m is from 0 to about 4, and n is at least about 12; for said diamines, m is from 0 to about 3, and n is at least about 6 when R.sup.1 is C.sub.2 -C.sub.3 alkylene, hydroxyalkylene, or alkenylene, and at least about 3 when R.sup.1 is other than C.sub.2 -C.sub.3 alkylene, hydroxyalkylene or alkenylene; for said polyamines and amine polymers, m is from 0 to about 10 and n is at least about 3; p is from 3 to 8; q is 1 or 0; t is 1 or 0, provided that t is 1 when q is 1; w is 1 or 0; x+y+z is at least 2; and y+z is at least 2.

Another group of preferred clay soil removal/anti-redeposition agents are the cationic compounds disclosed in European patent application 111,965 to Young S. Oh and Eugene P. Gosselink, published June 27, 1984, herein incorporated by reference. These cationic compounds are selected from the group consisting of:

(1) ethoxylated cationic monoamines having the formula: ##STR22##

(2) ethoxylated cationic diamines having the formula: ##STR23## wherein M.sup.1 is an N.sup.+ or N group; each M.sup.2 is an N.sup.+ or N group, and at least one M.sup.2 is an N.sup.+ group;

(3) ethoxylated cationic polyamines having the formula: ##STR24##

(4) ethoxylated cationic polymers which comprise a polymer backbone, at least 2 M groups and at least one L--X group, wherein M is a cationic group attached to or integral with the backbone and contains an N.sup.+ positively charged center; and L connects groups M and X or connects group X to the polymer backbone; and

(5) mixtures thereof;

wherein A.sup.1 is ##STR25## R is H or C.sub.1 -C.sub.4 alkyl or hydroxyalkyl, R.sup.1 is C.sub.2 -C.sub.12 alkylene, hydroxyalkylene, arylene or alkarylene, or a C.sub.2 -C.sub.3 oxyalkylene moiety having from 2 to about 20 oxyalkylene units provided that no O--N bonds are formed; each R.sup.2 is C.sub.1 -C.sub.4 alkyl or hydroxyalkyl, the moiety --L--X or two R.sup.2 together form the moiety --(CH.sub.2).sub.r --A.sup.2 --(CH.sub.2).sub.s --, wherein A.sup.2 is --O-- or --CH.sub.2 --, r is 1 or 2, s is 1 or 2 and r+s is 3 or 4; each R.sup.3 is C.sub.1 -C.sub.8 alkyl or hydroxyalkyl, benzyl, the moiety --L--X, or two R.sup.3 or one R.sup.2 and one R.sup.3 together form the moiety --(CH.sub.2).sub.r --A.sup.2 --(CH.sub.2).sub.s --; R.sup.4 is a substituted C.sub.3 -C.sub.12 alkyl, hydroxyalkyl, alkenyl, aryl or alkaryl group having p substitution sites; R.sup.5 is C.sub. 1 -C.sub.12 alkylene, hydroxyalkylene, alkenylene, arylene or alkarylene, or a C.sub.2 -C.sub.3 oxyalkylene moiety having from 2 to about 20 oxyalkylene units provided that no O--O or O--N bonds are formed; X is a nonionic group selected from the group consisting of H, C.sub.1 -C.sub.4 alkyl or hydroxyalkyl ester or ether groups, and mixtures thereof; L is a hydrophilic chain which contains the polyoxyalkylene moiety --(R.sup.6 O).sub.m (CH.sub.2 CH.sub.2 O).sub.n ]; wherein R.sup.6 is C.sub.3 -C.sub.4 alkylene or hydroxyalkylene and m and n are numbers such that the moiety --(CH.sub.2 CH.sub.2 O)-- comprises at least about 50% by weight of said polyoxyalkylene moiety; d is 1 when M.sup.2 is N.sup.+ and is 0 when M.sup.2 is N; n is at least about 12 for said cationic monoamines, is at least about 6 for said cationic diamines and is at least about 3 for said cationic polyamines and cationic polymers; p is from 3 to 8; q is 1 or 0; and t is 1 or 0, provided that t is 1 when q is 1.

Other clay soil removal/anti-redeposition agents which can be used include the ethoxylated amine polymers disclosed in European patent application 111,984 to Eugene P. Gosselink, published June 27, 1984; the zwitterionic compounds disclosed in European patent application 111,976 to Donn N. Rubingh and Eugene P. Gosselink, published June 27, 1984; the zwitterionic polymers disclosed in European patent application 112,592 to Eugene P. Gosselink, published July 4, 1984; and the amine oxides disclosed in U.S. application Ser. No. 516,612 to Daniel S. Connor, filed July 22, 1983, all of which are incorporated by reference.

Other optional ingredients which can be included in detergent compositions of the present invention, in their conventional art-established levels for use (i.e., from 0 to about 20%), include solvents, bleaching agents, bleach activators, other soil-suspending agents, corrosion inhibitors, dyes, fillers, optical brighteners, germicides, pH adjusting agents (monoethanolamine, sodium carbonate, sodium hydroxide, etc.), enzymes, enzyme-stabilizing agents, perfumes, fabric softening components, static control agents, and the like.

Except for the previously described enrobing of the soil release compound, granular formulations embodying the detergent compositions of the present invention can be formed by conventional techniques, i.e., by slurrying the individual components in water and then atomizing and spray-drying the resultant mixture, or by pan or drum granulation of the ingredients. Granular formulations preferably comprise from about 10 to about 30% detergent surfactant, usually anionic, and most preferably about 15 to about 25% surfactant.

Liquid formulations embodying the detergent compositions can be built or unbuilt. If unbuilt, these compositions conventionally contain approximately 15 to 50% (preferably 20 to 35%) total surfactant, from 0 to 5% (preferably from 0 to 2%) of an organic base such as a mono-, di-, or tri-alkanol amine, a neutralization system such as an alkali metal hydroxide and a lower primary alcohol such as ethanol or isopropanol, and approximately 20 to 80% water.

Built liquid detergent compositions can be in the form of single phase liquids provided that the builder is solubilized in the mixture at its level of use. Such liquids conventionally contain 10 to 40% (preferably 15 to 25%) total surfactant, 1 to 25% (preferably 3 to 20%) builder which can be organic or inorganic, up to 10% of a hydrotrope system, and 20 to 80% water. Built liquid detergents incorporating components that form heterogeneous mixtures (or levels of builder that cannot be completely dissolved) can also comprise detergent compositions of the present invention. Such liquids conventionally employ viscosity modifiers to produce systems having plastic shear characteristics to maintain stable dispersions and to prevent phase separation or solid settlement. Care should also be taken to avoid exposing the soil release compounds to highly alkaline environments, e.g. those above a pH of about 8.5, during processing of the liquid detergent formulation.

A description of some prefered detergent formulations is as follows:

A. Near Neutral Wash pH Detergent Formulations

While the detergent compositions of the present invention are operative within a wide range of wash pHs, they are particularly suitable when formulated to provide a near neutral wash pH, i.e. an initial pH of from about 6.0 to about 8.5 at a concentration of from about 0.1 to about 2% by weight in water at 20.degree. C. Near neutral wash pH formulations are better for enzyme stability and for preventing stains from setting. The near neutral pH of such formulations is also desirable to insure long term activity for the soil release compounds, especially those having shorter backbones. In such formulations, the product pH is preferably from about 7.0 to about 8.5, and more preferably from about 7.5 to about 8.0.

Preferred near neutral wash pH detergent formulations are disclosed in European Patent Application 95,204 to J. H. M. Wertz and P. C. E. Goffinet, published Nov. 30, 1983, herein incorporated by reference. These preferred formulations comprise:

(a) from about 2 to about 60% (preferably from about 10 to about 25%) by weight of an anionic synthetic surfactant as previously defined;

(b) from 0 to about 12% (preferably from about 0.5 to about 4%) by weight of a cosurfactant selected from the group consisting of:

(i) quaternary ammonium surfactants having the formula:

wherein R.sup.2, each R.sup.3, R.sup.4, R.sup.5, X and y are as previously defined;

(ii) diquaternary ammonium surfactants having the formula:

wherein R.sup.2, R.sup.3, R.sup.4, y and X are as defined above; particularly preferred are the C.sub.8 -C.sub.16 alkyl pentamethylethylenediamine chloride, bromide and methylsulfate salts;

(iii) amine surfactants having the formula:

wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5 and y are as defined above; particularly preferred are the C.sub.12 -C.sub.16 alkyl dimethyl amines;

(iv) diamine surfactants having the formula:

wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5 and y are as defined above; particularly preferred are the C.sub.12 -C.sub.16 alkyl dimethyl diamines;

(v) amine oxide surfactants having the formula:

wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5 and y are as defined above; particularly preferred are the C.sub.12 -C.sub.16 alkyldimethyl amine oxides; and

(vi) di(amine oxide) surfactants having the formula: ##STR26## wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5 and y are as defined above; preferred are the C.sub.12 -C.sub.16 alkyl trimethylethylene di(amine oxides) and

(c) from 0 to about 40% by weight (preferably 5 to about 30% by weight, and most preferably from about 10 to 20% by weight) of a fatty acid containing from about 10 to about 22 carbon atoms (preferably a C.sub.10 -C.sub.14 saturated fatty acid or mixtures thereof); the mole ratio of the anionic surfactant to the cosurfactant being at least 1 and preferably from about 2:1 to about 20:1.

Such compositions also preferably contain from about 3 to about 15% by weight of an ethoxylated alcohol or ethoxylated alkyl phenol (nonionic surfactants) as previously defined. Highly preferred compositions of this type also preferably contain from about 2 to about 10% by weight (preferably from about 3 to about 8% by weight) of a water-soluble polycarboxylate builder (preferably citric acid) and minor amounts (e.g., less than about 20% by weight) of neutralizing agents, buffering agents, phase regulants, hydrotropes, enzymes, enzyme stabilizing agents, polyacids, suds regulants, opacifiers, antioxidants, bactericides, dyes, perfumes and brighteners, such as those described in U.S. Pat. No. 4,285,841 to Barrat et al., issued Aug. 25, 1981 (herein incorporated by reference).

B. Detergent Formulations Containing Certain Anionic Surfactants

When high levels of certain anionic detergent surfactants are used, the compounds of the present invention may not deposit as well on the fabric during laundering. See U.S. Pat. No. 4,116,885 to Derstadt et al., issued Sept. 26, 1978, which describes the incompatibility of ethylene terphthalate/PEG terephthalate soil release polyesters with certain anionic detergent surfactants. These anionic surfactants include the alkyl sulfates and particularly the alkyl benzene sulfonates. Inclusion of certain detergent builders such sodium tripolyphosphonate, alkali metal carbonates and aluminosilicate ion exchange materials in such anionic detergent formulations further reduces the soil release activity of the compounds.

This decreased performance can be offset by inclusion of higher levels of nonionic detergent surfactant, i.e. above about 50% by weight of the surfactant system. However, higher levels of nonionic surfactants do not provide as good cleaning as anionic surfactants, especially in granular detergent formulations. Accordingly, inclusion of a small amount (e.g. from about 0.5 to about 2% by weight of the total composition) of a cationic detergent surfactant(s) as previously described can be used to improve the soil release performance of the compounds. Also, soil release performance can be boosted by simply including more of the compounds of the present invention.

A. Test Method

In testing the soil release performance of the polyester compositions, the following test method was used:

Polyester double knit (polyester) and 50%/50% polycotton t-shirt material (polycotton) fabrics were used in this testing. Using a Sears Kenmore washer, the fabrics were desized by washing with a liquid detergent composition containing the following ingredients:

The washing was conducted in 7 grain hardness water at a temperature of 95.degree. F. (35.degree. C.) for 12 minutes, with subsequent rinsing in 7 grain hardness water at a temperature of 70.degree. F. (21.1.degree. C.). This desizing step was done twice.

The desized fabrics were formed into swatches (11 in. square for the polyester fabrics, 3.times.11 in. for the polycotton fabrics). These desized swatches were then preconditioned with a detergent composition containing the above ingredients in conjunction with a solution or dispersion containing 1 to 100 ppm (wash concentration) of a soil release polyester composition. This preconditioning step was conducted in a 5 pot Automatic Mini-Washer (AMW). After the AMW pots were filled with 6 liters of water each, the detergent composition, and the solution/dispersion of soil release polyester composition, were added to each pot. Test swatches were then added to each of the filled pots. The wash cycle was conducted in 7 grain hardness water at a temperature of 95.degree. F. (35.degree. C.) for 12 minutes. After the wash cycle, there was a 2-minute spin cycle, followed by a 2-minute rinse cycle using 7 grain hardness water at a temperature of 80.degree. F. (26.7.degree. C.).

Union Guardol 76 SAE 30 detergent clean motor oil colored with 0.075% red EGN dye was used to soil these preconditioned swatches. For the preconditioned polyester swatches, 100 microl. of this soil was placed on 3 separate spots. Similarly, for the preconditioned polycotton swatches, 50 microl. of this soil was placed on 3 different spots. The stained swatches were placed on racks and allowed to wick for at least 16 hours.

The soiled swatches were then washed in the AMW with the above detergent composition (without addition of the soil release polyester composition) using the same wash, spin and rinse cycle conditions as in the preconditioning step. After the rinse cycle, the test swatches were dried in a mini-dryer. Gardner Whiteness meter readings (L, a and b) were then determined for each test swatch. Soil release performance in terms of Hunter Whiteness Values (W) was then calculated according to the following equation: ##EQU2## The higher the value for W, the better the soil release performance. B. Test Results

In summarizing test results, the polyester compositions are identified by: (1) the average number of monomer units in the backbone of the polyesters; and (2) the number of methyl capped PEGs at the end of the polyester backbone. The following nomenclature is used to identify the monomer units and methyl capped PEGs:

T=terephthalate

TM=trimellitate (1,2,4-benzenetricarboxylate)

SIP=5-sulfoisophthalate

M=trimesate (1,3,5-benzenetricarboxylate)

EG=ethylene glycol

PG=1,2-propylene glycol

MeE.sub.n =methyl capped PEG, n being the average number of ethoxy units (--CH.sub.2 CH.sub.2 O--) in the PEG

For example, 2.75 T, 1.75 EG, 2 MeE.sub.16 represents a polyester composition where the polyesters have an average of 2.75 terephthalate units, 1.75 ethylene glycol units and two methyl capped PEGs, the PEG having an average 16 ethoxy units.

1. Efficiency of Propylene Glycol Based Polyesters

The soil release performance of a 2.75 T, 1.75 PG, 2 MeE.sub.16 polyester composition was tested at different levels. In this testing, aqueous solutions of the polyester composition were added during the preconditioning step. The results are shown in Table I:

2. Efficiency of Ethylene Glycol Based Polyesters

The soil release performance of a 2.75 T, 1.75 EG, 2 MeE.sub.16 polyester composition was tested at different levels. In this testing, phenoxyethanol solutions of the polyester composition were added during the preconditioning step. The results are shown in Table II:

3. Variations in Polyester Backbone and Methyl Capped PEGs

The soil release performance of polyester compositions having different polyester backbones and different methyl capped PEGs at the end of the polyester backbone was tested. In this testing, aqueous dispersions (10 ppm wash concentration) of the polyester compositions were added during the preconditioning step. The results are shown in Table III:

4. Number of Terephthalate Units in Polyester Backbone

The soil release performance of ethylene glycol based polyester compositions having different average numbers of terephthalate units in the polyester backbone were tested. In this testing, aqueous dispersions (10 ppm wash concentration) were added during the preconditioning step. The results are shown in Table IV.

5. Comparison of Block Polyesters to Milease T.RTM.

The soil release performance of block polyester compositions of the present invention (2.75 T, 1.75 EG. 2 MeE.sub.16) were compared to a Milease T.RTM. polyester composition. In this comparison, phenoxyethanol solutions of the polyester compositions were added during the preconditioning step. The results are shown in Table V:

The following embodiments illustrate, but are not limiting of, detergent compositions of the present invention:

A granular detergent composition is as follows:

Except for the enrobed polyester particles, the components are added together with continuous mixing to form an aqueous slurry which is then spray dried to form granules. The enrobed polyester particles are then mixed with the granules to form the composition.

A liquid detergent composition is formulated as follows:

The components are added together with continuous mixing to form the composition.

Liquid detergent compositions are as follows:

Embodiment III is prepared by adding the components together with continuous mixing, in the following other to produce a clear liquid: a paste premix of alkylbenzene sulfonic acid, a portion of the sodium hydroxide, propylene glycol, and a portion of the ethanol; a paste premix of alkylpolyethoxysulfuric acid, a portion of the sodium hydroxide and a portion of the ethanol; pentaacetic acid; a portion of the alcohol polyethoxylate; a premix of water, triethanolamine, brighteners and the remainder of the alcohol polyethoxylate; the remaining ethanol; potassium hydroxide and the remaining sodium hydroxide; citric acid; fatty acid; formic acid, boric acid and calcium; alkyl trimethylammonium chloride; PEA.sub.189 E.sub.17 (50% aqueous solution); polyester of Example 1; adjust to pH 8.0; and balance of components. Embodiment IV can be prepared in a similar manner.