CA2054654A1

CA2054654A1 - Method of improving the soil anti-redeposition properties of washing detergents and products

Info

Publication number: CA2054654A1
Application number: CA002054654A
Authority: CA
Inventors: Thomas L. Krinski; Tam H. Tran
Original assignee: Protein Technologies International Inc
Current assignee: Solae LLC
Priority date: 1991-08-26
Filing date: 1991-10-31
Publication date: 1993-02-27
Also published as: JPH05117689A; JP2586974B2; NZ240224A; AU656922B2; EP0530418A1; KR930004450A; SG68545A1; AU8679491A; IE913857A1

Abstract

METHOD OF IMPROVING THE SOIL ANTI-REDEPOSITION
PROPERTIES OF WASHING DETERGENTS AND PRODUCTS

ABSTRACT

A detergent composition and method may have the soil anti-redeposition properties significantly and unexpectedly improved by incorporating into the detergent composition an effective amount of an anti-redeposition agent. The anti-redeposition agent is a casein material which has been modified with an ionic monomer. Ionic monomers which have been found to be especially effective at improving the anti-redeposition properties of washing detergent compositions are cationic epoxide monomers, cationic acrylate monomers and cationic chlorohydrin monomers. Anionic or carboxylated casein derivatives have also been shown to be effective anti-redeposition agents.

Description

~ETHOD OF IMPROVING THE SOIL
ANTI-REDEPOSlTION PROPERTIES OF ~ASHING DETERGENTS
AND PRODUCTS

~CKGROUND OF ~HE_lNVEN~ION

This application is related to Canadian ~pplication filed August 30, 1991.

~ his invent~on relates to detergent compositions and methods of forming detergent compositions. The detergent composltions formed have greatly ~mproved soil removal and/or anti-redeposition properties.
~hese properties have been found to be unexpectedly improved by the addition of a modified casein material which provides greatly improved and unexpected anti redeposition properties. Further, the modified casein material is rapidly biodegradable, thus s1gnificantly improving the env1ronmental properties of the detergent as a whole.

1~ Applicants are aware of the following U.S. Patents, the disclosures of which are incorporated by reference herein.

U.S. Patent 3,000,830 U.S. Patent 3,594,324 U.S. Patent 4,352?692 U.S. Patent 4,474,694 U.S. Patent 4,689,381 Synthetic detergent compositions have been used commercially for ~any years for the removal of soil from fabric. ~hese materials generally are combinations of a number of d~fferent compounds or SP-999~12~6~'~

~dditlves. These compositions ~ay ~nclude, although they are not necessarily limited to, an organic detergent compound such as a surfactant or surface active agent, builder components such as a -phosphate salt which enhances the cleaning effectiveness of the surfactant by sequestering various metal ions found in hard water and also a so~l suspending or anti-redeposition agent to help the surfactant hold the soil part~cles in suspension and prevent them from being redeposited onto the fabric during washing.

The use of a soil anti-redeposition agent generally improves the whiteness of fabrics washed with the detergent or the brightness of the color, since the anti-redeposition agent suspends the soil in the solution once it has been removed from the fabric and prevents its redeposition onto the washed fabric. If the detergent composition has poor soil suspension properties during washing and the soil is allowed to be redeposited or to settle from the wash water onto the washed fabric, the fabric will eventually acquire a gray or dull appearance, which is extremely undesirable aesthetically.

A number of materials have been used as soil anti-redeposit~on agents. Once of the most widely used material is carboxymethylcellulose. Carboxymethylcellulose has been added for a number of years to different types of detergent compositions used for washing fabrics to prevent redeposition of soil from solution once the soil has been removed from the fabric by washing. Other ~aterials which SP-999.1 2 have been proposed or used as so~l anti-redeposit~on agents lnclude sodlum polyacrylate, polyvinyl acetate, ethylcelluloses, polyvinyl alcohols, sod~um alg1nate and various ~odif~ed starches. All of the above are generally regarded as being less effectlve than carboxymethylcellulose. Other types of soil anti-redeposit~on agents wh~ch have been described as having ~mproved soil anti-redepos~tion properties over carboxymethylcellulose 1nclude polyvinylpyrrolidone, as described ~n U.S. Patent 3,000,830, and a combination of carboxymethylcellulose and gelatin protein as described in U.S. Patent 3,594,324. ~hile use of these materials as soil anti-redeposition agents ~n detergents has been somewhat successful, non the less, a need still exists for an ~mproved material having better soil anti-redeposition properties and one which is readily adaptable and useful in a wide variety of detergent composition. It is particularly desirable to develop a so~l anti-redeposition agent which is more effective in llquid detergent compositions. Carboxymethylcellulose and ethylcelluloses, for example, and other state of the art redeposition agents, typically have very poor solubility in the solutions which make up liquid detergent compositions. As a result, these ~aterials have very low effectiveness as soil anti-redeposition agents in liquid detergent compositions.

Applicants have found that a modified casein material, particularly a modified casein material which incorporates a cat~onic monomer, and ~n particular a cationic chlorohydrin, epoxy and/or ~p,, 999 . 1 2 ~ 4 acrylate monomers, have unexpected soil anti-redeposition properties.
These soil anti-redeposition properties are observable ~hen the mater~al ~s used ln liqu1d detergent compositions or in dry powdered detergent co~posit~ons. Horeover, these modified casein materials exh~bit an unexpected improvement ~n soil anti-rQdepos~tion properties in many detergent systems. Applicants' anti-redepos1tion materials are effective in llquid and powered detergents even ~f used ~n cool or hot ~ater. Appllcants' anti-redeposition materials are effective when used with a varlety of conventional washing detergent materials, including surfactants, builders and additives. Applicants' anti-redeposition mater1als are effective on a wide variety of soils and for a wide variety of fabrics.

It ~s therefore an object of the present invention to provide a method of improving the soil anti-redeposition properties of detergent compositions.

It is a further object of the present invention to provide a detergent composition which has greatly ~mproved soil anti-redeposition properties.

It is also an ob~ect of the present invention to prov1de a method of improving the soil anti-redepositlon properties of detergent mater~als by incorporating a modified casein compound in the detergent composition.

SP-999. 1 2~

It is an ob~ect of this ~ m ention to improve the blodegradable properties of washing detergents.

It is an ob~ect of thls invention to provide a modified casein soil anti-redepos~tion agent for washing detergents.

It is an object of this invention to provide an ionically modified soil anti-redeposition agent for washing detergents.

lt is an object of this invention to provide cationically and anionically modified casein soil anti-redeposition agents for washing detergents and to provide a method using such soil anti-redepostion agents.

These and other objects will be apparent from the follow1ng Description of the Preferred Embodiments.

~ESCRIPTION OF THE PREFERRED EMBODIMENTS

~ he unique material which is employed in the production of a 1~ detergent containing a soil anti-deposition agent is a modifled casein ~aterial. These materials are obtained by mod~fying a caseln with a cationic monomer. Epoxide, chlorohydrin and acrylate cationic ~onomers have been found to be particularly suitabte for use ~n this invention.

sp-99~. l 2~6~4 Anionic phthalate monomers have also been found su~table for ~od1fying the casein ~aterial ln the ~anner generally described in U.S. ~,474,674, ~hlch descr~bes such a reaction for vegetable protein.

The casein material which is modified pursuant to the present 1nvent~on ~s not critical and can be selected from any type of case~n 1ncluding ac1d precipitated casein, lactic acid casein, as well as various caseinate salts such as sodium caseinate.

A fairly conventional detergent composition may be used with applicants' ant~-redeposition agents to prepare either a dry powdered detergent or a liquid detergent which exhibits unexpected soil anti-redepos~t~on prope~ties. Such a detergent composit~on may be formulated by employ1ng an organic detergent substance or surfactant. The surfactant may be chosen from any of the conventional anionic, nonion k, amphoteric or zwitterionic surfactants, which can be used alone or in 1~ combination to produce a detergent composition containing applicants' anti-redeposition agent. The following description of materials represents only ~llustrations of the numerous detergents which can find use w~th applicants' anti-redeposition agent.

The anionic organic detergent compounds or anionic surface active agents may include detergent compounds which contain an organic hydrophobic group and an ionic solubilizing group. Typ~cal examples of lonlc solubilizing groups are sulphonate, sulphate, carboxylate and SP-999. 1 phosphate. Examples of suitable an~onic detergents which wou 2 ~ ~ ~ 6 wlthin the scope of the ~nvention include the water soluble salts of h1gher fatty ac~ds or resin acids such as may be derived from fats, oils and waxes of an~mal or vegetable or~g~n and the sulphated and sulphonated synthetic detergents. Also included in the class of suitable detergent compounds ~nclude suitable anionic detergents such as the higher alkyl aryl sulfonates such as the alkyl benzene sulphonates as well as the sulphates of higher alcohols such as sodium lauryl sulfate and similar materials.

Non~onic synthetic detergent compounds do not ionize in solution and the whole ~olecule acts as a cleaning agent. Those compounds which can be generally or broadly used in the present ~nvent10n can be broadly defined as compounds produced by the condensation of alkyloxide groups which are hydrophilic in nature with an organic hydrophobic compound 1~ which may be aliphatic or aromatic in nature. The most widely used class of noionic synthetic detergents include those which are formed by noionic synthetic detergents include those which are formed by condensing ethylene oxide or propylene oxide with a hydrophobic base.
However, other suitable nonionic organic synthetic detergent compounds including the polyethylene oxide condensates of alkyl phenols, as well as condensation products of materials such as ethylene oxide and the product resulting from the reaction of propylene oxide with ethylene oxide, the long chain tertiary amine oxides and the long chain alkyl phosphates may all be used with applicants' invention.

SP-999. 1 20~65~

Amphoteric synthetic detergent compounds can be described as derivatives of aliphatic secondary and tertiary amines. Examples of specific compounds within this general grouping are mater~als such as sodium-3-dodecylaminoproprionate. Amphoteric surfactants have both positive and negattve centers and assume either a positive (cationic) or negative (anionic) charge depending on the pH of the solution.

~ w~tterionic synthet~c detergent compounds behave similarly to noionic surfactants and can be described as derivatives of aliphatic quarternary ammonium phosphonium, halide and sulfonium compounds.
Examples of specific compounds falling within this definition are materials such as N, N-dimethyl-N-hexadecyl amino propane-1-sulfonate.
~hese latter compounds are especially preferred for detergent characteristlcs in relatively cool water.

The detergent composition of the present invention can further include typical but non-limiting ingredients to improve other properties of the detergent composition. Included within this grouping of materials include compounds such that are described typically as water soluble builder salts such as phosphates which are added for purposes of enhancing the cleaning power of the detergent composition. Furthermore, various other materials may also be present such as materials to improve detergency of the composition and modify the foaming properties in whatever manner desired as well as various optical brightening agents, SP-999. 1 2 ~

fluorescent ~hitening agents and the like. 6ermic~dal lngredients may also be added to i~prove the overall cleaning or d~sinfecting properties of the detergent composition of the present ~nvention. The present 1nvention ~s not intended to be limited by the exact contents of the detergent compositlon of the present ~nvention since numerous materials are well known and well within the knowledge of those skilled 1n the art ~n the production of detergents.

~ he above general groupings of organic detergent compounds may be used s~ngly or in combinat10n in the practice of th~s invention with appllcants' modified protein material. These mater~als represent specific illustrations of many of the numerous conventional organic detergent compounds or surfactants which can find application within the scope of the invention. These materials may be used ln dry powdered washlng materials or as 11quid detergent washing materials, as known in the art, with the novel addition of the mod~fied casein material to produce washing compounds having unexpectedly improved anti-redeposition properties, and in particular to produce liquid detergent compounds having greatly improved soil anti-redeposition properties.

Moreover, applicants' modified casein mater~al perm~ts replacement of a substantial portion of the compounds making up washing detergents with a readily biodegradable material. This significantly reduces the period that effluent detergent washing material remain the environment, since the conventional anti-redeposition materials which are replaced SP-999. 1 ~ o~5S~4 break down very slowly ln the environment. Applicants' ~nti-redepos~tion agents may be used a levels of from about 0.2 to 5X by ~e1ght of the detergent compos~tion, and typically would be used at a -level of from about 0.5 to 2X by weight of the total for~ulatlon, though the amount is not crltical. S1nce applicants' product will break down 1n the env1ronment ~n a matter of days, rather than years for some petroleum base materials, a very significant and unexpected improvement ~n the env~ronmental performance of the washing compound can be ach~eved.

The following example is given to further illustrate the specific embodiments of the present invention and the ~mprovements achieved thereby.

ExamDle I

A liquid detergent material was formulated as follows:

8.3 parts Neodol 2~-9 (TM, Shell Chemical) 16.7 parts sodium alkyl benzene sulfonate 73.0 parts water 2.0 parts anti-redeposition agent (The control did not contain an anti-redeposition agent.) SP-999.l The anti-redepos1tion agent used was a cationic modtfied caseln ~aterial produced as described below.

- Acid precipitated casein is suspended in water to a solids level of about 3-5% by weight. The pH of the suspension is adjusted to about 9 to 10 by the addition of sodiu~ hydroxide. To the suspension is added 3-chloro 2-hydroxypropyl trimethyl ammonium chloride in an amount of 10%
by weight of the solids. The casein is reacted at a pH of 9-lO at 60OC
for one hour. Following reaction the modified casein is precipitated at a p~ of about 4.5 and separated.

The control detergent and the detergent composition containing the mod~fied casein were evaluated for effectiveness in preventing the redeposition of soil on fabric during washlng. Five replications of 3x3 ~nch white swatches of 50/50 polyester/cotton were impregnated with .01%
carbon black. The swatches were then washed five cycles in a conventional test washing machine. ~ash temperature was 25oC. Wash time was 10 m~nutes. The detergent concentration was 0.15% by weight of the wash water. The fabric was rinsed once per cycle with 10% of the wash liquor left ~n the swatches of fabric. The comparative results from ~xample 1 are set forth in Table 1.

~otal redeposition measured by the reflectance of the fabric is reported. Higher numbers indicate less soil redeposited. Reflectance was measured by a Hunter Colorimeter Model ~PC2 ~ , using the Y index.

sp-99-9~ l 2 Q ~ 4 TABI~l Pol~mer ~ash T.C Reflectance (Total R) Modified Casein 25 66.0 Control 25 57.1 It may be seen that the modified casein of the present invention had improved redeposition properties over the-control sample.

Although the present invention has been descrtbed relative to the specific embodiments set forth herein, it is intended to ~nclude within the scope of the present invention all reasonable equlvalents, substitutions and modifications thereof as will be appreciated by one skilled in the art. Applicant is not to be limited by the embodiments given herein for purposes of ~llustration but only by the claims appended hereto and their equivalents.

Claims

1. In a laundry detergent having one or more surfactants and additive materials the improvement comprising the addition of a soil anti-redeposition agent, which is a casein material modified by reaction with an anionic and cationic monomer, in an amount of at least about 0.2% by weight to substantially reduce the amount of suspended soil which is redeposited on washed fabric during a wash cycle.

2. The laundry detergent of claim 1 wherein the casein material is modified by a cationic monomer.

3. A laundry detergent having a surfactant and additive materials the improvement comprising the addition of a soil anti-redeposition agent, which is an epoxy modified casein material, in an amount effective to substantially reduce the amount of suspended soil which is redeposited on washed fabric during a wash cycle.

4. A laundry detergent having a surfactant and additive materials the improvement comprising the addition of a soil anti-redeposition agent, which is an acrylic modified casein material in an amount effective to substantially reduce the amount of suspended soil which is redeposited on washed fabric during a wash cycle.

SP-999.1

5. The laundry detergent of claim 1 wherein the laundry detergent is a liquid detergent.

6. The laundry detergent of claim 1 wherein the laundry detergent is a powdered detergent.

7. A laundry detergent having a surfactant and additive materials the lmprovement comprising the addition of a soil anti-redeposition agent which is a casein materlal modified by reaction with a cationic monomer selected from the group consisting of 3-chloro 2-hydroxypropyltrimethyl ammonium chloride, 4-chlorobutene trimethyl ammonium chloride and 2,3 epoxypropyltrimethyl ammonium chloride in an amount effective to substantially reduce the amount of suspended soil which is redeposited on washed fabric during a wash cycle.

8. The laundry detergent of claim 1 wherein the casein material is modified by an anionic monomer.

9. The laundry detergent of claim 1 wherein the soil anti-redeposition agent is biodegradable.

10. The washing laundry detergent of claim 1 wherein the soil anti-redeposition agent is biodegradable.

SP-999.1

11. A method of improving the soil anti-redeposition properties of a laundry detergent comprising one or more surfactants, comprising adding to the laundry detegent an anionic or cationic modified casein material in an amount at least about 0.2% by weight to substantially reduce the amount of suspended soil which is redeposited on washed fabric during a wash cycle.

12. An improved laundry detergent in the form of a surfactant, and any additive materials, containing, as the improvement, a casein material modified by reaction with an anionic or cationic monomer an an amount in the range of 0.2 to 5 percent by weight of the detergent effective to reduce substantially the amount of suspended soil which is redeposited on washed fabric during a wash cycle.

13. The laundry detergent of claim 12 wherein the cationic monomer is a cationic monomer selected from the group consisting of 3-chloro 2-hydroxypropyl trimethyl ammonium chloride, 4-chlorobutene trimethyl ammonium chloride and 2, 3 epoxypropyltrimethyl ammonium chloride.

14. The laundry detergent of claim 12 wherein the casein material is modified by an anionic phthlate monomer.