Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/38—Products with no well-defined composition, e.g. natural products
  • C11D3/386—Preparations containing enzymes, e.g. protease or amylase
  • C11D3/38618—Protease or amylase in liquid compositions only
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/38—Products with no well-defined composition, e.g. natural products
  • C11D3/386—Preparations containing enzymes, e.g. protease or amylase
  • C11D3/38663—Stabilised liquid enzyme compositions

Definitions

• Household laundry detergent compositions are formulated to remove soil and stains from various kinds of dirt depositions in the fabric. Generally such formulations effectively remove dirt induced soil and are even effective in removing low level strains or soil from oil or grease sources.
• common laundry detergents are deficient in handling soil resulting from protein sources, e.g., blood, grass; or soil where the proteins are combined with oils or greases from animal or vegetable origin; or soils of heavy grease, fats, or starch origin.
• compositions are being marketed as “prewashes” or “pre-spotters”. Such compositions are applied directly to the difficult stains before the washing process.
• the "pre-wash” compositions are formulated primarily to remove oily or greasy stains.
• Such compositions rely principally upon organic based solvents such as hydrocarbons, halogenated hydrocarbons etc. in combination with hydrocarbon compatible surfactants.
• Such compositions effectively dissolve and/or emulsify oily or greasy stains.
• These compositions are not nearly as effective in removing stains caused by protein sources such as blood, and grass; or from combined protein and fat sources such as sebum; or from fats and starches. These sources produce stains which are difficult to remove with solvent/surfactant combinations alone.
• compositions that are available from various sources. These compositions employ protease, amylase, or lipase enzymes to attack protein, fat and starch based stains and chemically degrade these compounds so that they can more readily be removed by subsequent or concurrent treatment with conventional surfactants. While enzyme containing compositions are quite proficient in treating such stains, the enzymes themselves are quite susceptible to deactivation if mixed with other components, especially hydrocarbon solvents.
• the present invention relates to laundry "pre-wash” compositions; and more particularly to pre-wash compositions that are single phase liquids effective against both oil and grease stains as well as protein, fat and/or starch stains.
• the invention compositions effectively combine the advantages of both hydrocarbon oil and grease solvents and enzymes in a single liquid composition.
• the normally incompatible hydrocarbon solvents and enzymes are combined without expressively limiting the products' "shelf-life", i.e., the enzyme component retains an effective activity against stains for extended periods; and the hydrocarbon solvents retain their effectiveness against oil and grease stains.
• the enzymes are water soluble and they must remain in aqueous solution to retain their activity against proteins, fats, and/or starches.
• the hydrocarbon solvents are quite hydrophobic and immiscible in aqueous solutions. The hydrocarbon solvents are effective against oil and grease in the absence of water. Any water present in the "pre-wash" composition tends to interfere with the solvents' ability to remove oil and grease.
• the present compositions reconcile these adverse properties by dispensing aqueous solutions of the enzymes as "reversed micelles" within the hydrocarbon solvent/surfactant medium.
• the "reversed micelles” are formed by providing suitable surfactants which facilitate encapsulation of an aqueous solution of the enzymes and subsequently dispersing the enzyme/surfactant mixture in the hydrocarbon solvent medium.
• the enzymes are dissolved in the aqueous solution; surfactants are added.
• the surfactants encapsulate the enzymes, and then permit the dispersion of the enzyme-aqueous portion in the hydrocarbon medium.
• a single phase stable liquid soil removal composition comprising enzymes dissolved in aqueous solution encapsulated within reversed micelles, said composition comprising, by weight, 25-35% nonionic surfactant, 60-70% hydrocarbon solvent, and 0.1 to 1.0% stabilized enzymes, and in which the weight of solvent to surfactant is about 2:1 said micelles being obtained by:
• the nonionic surfactants effectively facilitate the formation of reversed micelles.
• the hydrophobic tail of the surfactant dissolves in the hydrocarbon medium, while the hydrophilic head of the surfactant dissolves in the aqueous enzyme solution.
• minute micelles are formed within the hydrocarbon medium.
• the enzymes are dissolved within the aqueous micelle interior where they are effectively protected from attack and degradation by the hydrocarbon solvent.
• the hydrocarbon component attacks and removes the oil and grease stains without interference from the aqueous portion of the composition since the aqueous portion is but a minor amount, less than 5% of the composition.
• the enzymes are released upon the fabric surface where they can effectively attack the protein, fat, and/or starch stains.
• aqueous enzyme-surfactant "reversed-micelles” are extremely small and are dissolved within the hydrocarbon medium to form a suspension or dispersion. Thus there is no problem with phase separation. Further, due to the unique fine structure, i.e., reversed micelles, the enzymes in the aqueous portion are protected from premature degradation by the surrounding hydrocarbon medium.
• the enzyme stabilizers may for example be sodium chloride, calcium chloride, or triethanolamine.
• the compositions according to the invention may contain small percentages of hydrotropes, such as glycols but this is not essential. Small amounts of perfumes or dyes may be included for aesthetic purposes.
• the pre-wash compositions are prepared by the procedure specified above so as to produce a solution of reversed micelles having the aqueous enzyme solution held within the interior thereof; and with the micelles dispersed throughout the hydrocarbon solvent-surfactant medium.
• compositions may comprise several tenths of a percent of solution (as a glycol/water solution) enzyme; about a tenth of a percent of NaCi (as enzyme stabilizer); less than five percent water; twenty-five to thirty-five percent nonionic surfactant; sixty to seventy percent hydrocarbon solvent; the ratio of solvent to surfactant being about 2:1, and about two to three percent of a glycol as a hydrotrope; and if desired, several tenths of percent perfume and coloring material (dye).
• the water dissolved enzyme may comprise about 0.2 weight %; the composition may further comprise about 1.5 weight % of 1 M NaCI aqueous solution; about 2.5 weight % of ethylene glycol; about 14.5 weight % of an ethoxy-propyloxy linear alcohol nonionic surfactant; about 14.5 weight % of an ethoxylated linear alcohol nonionic surfactant; with the remainder being hydrocarbon solvent, e.g., a nominal C-12 to C-16 mixture of isoparaffins. Very small percentages of perfumes or coloring agents may be added.
• the enzyme component is present to effectively remove protein based stains, fat based stains, and/or starch based stains.
• proteases are most desirable in compositions according to the invention. It should also be apparent that related enzymes having particular effectiveness against other organic molecules, e.g., starches, fats, etc., may also be included along with the proteases. If desired, amylases, lipases etc. may be combined with the protease enzymes to produce a pre-wash composition that is effective against a full spectrum of fabric stains. The only precaution to be taken if additional enzymes are introduced, is that such added enzymes be compatible with the protease.
• the total amount of water in the compositions according to the invention is maintained at levels of less than 5 weight %. Quantities of water greater than 5 weight % interfere with the ability of the hydrocarbon solvent to effectively remove oil and grease stains.
• Pre-wash compositions according to the invention exhibit the ability to simultaneously remove oil/ grease stains and protein, fat, and/or starch stains from fabrics and are formulated from nonionic surfactants, enzymes, and hydrocarbon solvents. While enzymes and hydrocarbon solvents are normally incompatible, the compositions according to the invention overcome this difficulty by enclosing the enzymes in nonionic surfactants, and then dispersing the mixture in hydrocarbon solvents. Reversed micelles are thus formed in the surfactant-hydrocarbon medium. The water content of the composition is kept very low, i.e., less than 5 weight %, so that the oil and grease stain removing ability of the hydrocarbon solvent substrate remains unimpaired. At the same time the encapsulated enzymes are released to attack protein stains when the pre-wash composition is applied to soiled fabrics.
• the pre-wash compositions according to the invention comprise a hydrocarbon solvent medium in which surfactants are dispersed, as well as an aqueous enzyme solution in the form of reversed micelles.
• the dispersed surfactants form the "micelle" interface between the aqueous enzyme solution and the surrounding hydrocarbon solvent medium.
• the hydrocarbon solvent comprisies the major component, being present in amounts from 60 to 70% by weight.
• the nonionic surfactants comprise the next most abundant component, ideally being present in an aggregate amount in the neighborhood of 30%. It is desirable that the solvent-surfactant ratio be maintained at about 2:1, e.g., if the solvent is 60%, then the surfactants should be present at about 30%.
• the total amount of solvent and surfactant is not critical; however, together they should comprise well over 90% of the composition.
• the component that is critical to the effectiveness of the pre-wash compositions is water.
• Water comprises the solvent for the enzymes and its presence is necessary for that purpose.
• the water content rises appreciably above 5% there is a noticeable decrease in the solvents' ability to thoroughly remove oil and grease stains. Therefore, the water content is always kept at less than 5%.
• the water acts as a solvent for the enzyme component, which is necessary to remove protein, fat and/ or starch based stains.
• the enzymes are dissolved in the water.
• the enzymes are stabilized in the aqueous solution, for example, by the addition of salt (NaCl). Only a small percentage, e.g., several (i.e. 1,2,3,4,5 5 or 6) tenths of a percent of the enzyme solution is needed to be effective. Higher amounts of enzymes may also be utilized, but will add to the cost of materials.
• K.N.P.U. means Kilo Novo Protease Units. There is no industry- wide standard for measuring activity), about 0.2% by weight is an effective amount.
• Such enzyme solutions may be further stabilized by the addition of 1-2% of a 1M NaCI solution.
• a hydrotrope such as ethylene glycol can be added in low percentages, e.g., 2-3%, to aid the solubility of the surfactants in the solvent.
• the ratio of solvent to surfactant is about 2:1.
• compositions When produced in accordance with the procedure according to the invention the compositions are a clear solution with the enzymes encapsulated in reversed micelles within the surfactant-hydrocarbon solvent medium.
• the compositions exhibit excellent activity against both oil and grease stains as well as protein, and/or starch and/or fat-based stains.
• the compositions also retain an appreciable portion of the enzyme activity when stored for extended periods.
• the selection of the enzymes for use in the compositions may be made from any number of commercially available liquid enzyme solutions that are useful against proteins, lipids and starchy substances. Such enzyme solutions are available from several commercial sources.
• alkaline proteases are derived from various strains of the bacterial Bacillus subtilis. These proteases are also known as subtilisins, and are available under the trademarks Esperase ® , Savinase ⁇ , and Alcalase®, from Novo Industri A/S, of Bagsvaerd, Denmark; and also under the trademarks Maxatase ® and Maxacal® from Gist-Brocades N.V. of Delft, Netherlands.
• proteases are supplied as aqueous stabilized solutions of the enzyme.
• the enzymes are generally stabilized by the addition of glycols such as propylene glycol.
• glycols such as propylene glycol.
• These solutions are also supplied in various strengths wherein the strengths are defined by the activity exhibited by the enzyme.
• the enzyme solution has an activity of 8 K.N.P.U.
• enzyme solutions of lesser or greater activity can be utilized in the invention compositions.
• lipases effective against fats; or amylases, effective against starches can also be used in the formulations. Both types of enzymes are commercially available, e.g. lipases - (see U.S. Patent 3,950,277 column 3, lines 15-55 for a description of lipase enzymes, their origins, and sources; amylases - Rapidase O from Societa Rapidase, France; and Milezyme O from Miles Labs., Elkhurst, Ind.
• compositions also may include agueous salt solution as stabilizing agent. While the exact amounts of the stabilizer is not critical, the inclusion of roughly 1.5 weight% of 1M NaCI to the aqueous enzyme solution has been found to aid in maintaining enzyme activity when the product is stored.
• Nonionic surfactants comprise a major component of the pre-wash compositions.
• Surfactants that are compatible with the hydrocarbon solvent medium are most necessary; and in addition such surfactants must not degrade, or interfere with the enzymes in the reversed micelles.
• the surfactants are also responsible for the micelle formation within the hydrocarbon medium.
• the long chain alcohols such as linear ethoxylated and linear propoxylated alcohols and mixtures thereof are particularly useful in the compositions according to the invention.
• Such surfactants are completely compatible with the hydrocarbon solvents; they efficiently form reversed micelles to encapsulate the aqueous enzyme solutions; they do not degrade the enzymes; and they contribute significantly to the removal of soil from fabrics to which the compositions are applied.
• Alkyl ethoxylated and propoxylated alcohols in the nominal C-12 to C-16 range are most preferred.
• Such surfactants are available as standard articles of commerce under the name "BiosoW” from the Stepan Chemical Co.; or under the name “Neodol ® " from the Shell Chemical Co.
• the "Biosoft” series of nonionic surfactants are ethoxylated and propoxylated fatty alcohols sold in liquid form.
• the "Neodol” series of surfactants comprise a large group of nonionic surfactants including ethoxylated long chain alcohols with ethoxy groups ranging from 3 to 12 and the carbon chains from 12 to 15.
• Neodol 25-3 is composed of carbon chains nominally in the C-12 to C-15 range with an average of three ethoxy moieties per mole of alcohol.
• Biosoft EA-10 is a mixture of ethoxylated and propoxylated long chain fatty alcohols wherein the carbon chains are nominally in the C-10 to C-12 range with an average of 7.1 ethoxy and 2 propoxy moieties per mole of alcohol.
• nonionic surfactants can be substituted for the aforementioned surfactants in the compositions so long as they met the criteria set forth above.
• nonionic surfactants are included in the compositions in substantial quantities making up somewhat less than one-third of the weight. While the total surfactant percentage is not critical, they are present in about one-half the amount of hydrocarbon solvent. This ratio of surfactant to solvent is necessary to achieve good removal of oil and grease based soil wherein both the hydrocarbon solvent and surfactants play key roles.
• the hydrocarbon solvent is the major component in the compositions and, in conjunction with the surfactants, is the primary agent for treating oil and grease based stains.
• the hydrocarbon solvent comprises well over half the compositions by weight; the percentages are in the 60-70% range.
• the solvent component can be selected from any number of hydrocarbon based oil and grease solvents. Such materials are staple industrial products and may be procured from a number of oil industry sources.
• the solvent component be compatible with the formation of micelles, in this instance reversed micelles, i.e., micelles having an encapsulated aqueous component dispersed within an organic solvent medium. Because of this requirement it is desirable to employ solvents that are low in sulfur, acids, and oxygenated compounds. Pure hydrocarbon solvents, especially paraffinic hydrocarbons having fairly long carbon chains, e.g., C-10 to C-14 are highly preferred for use in the compositions. Such solvents are available from the Exxon Corporation of Houston, Texas under the trademark “isopar ® " and "Norpar g ".
• Both of these groups of hydrocarbon solvents have a very high (98%) normal or isoparaffin content and very low concentrations of sulfur, acids, carbonyls, chlorides, etc. These solvents, or their equivalents from other manufacturers, are the preferred organic solvents for use in the compositions.
• compositions wherein the aqueous enzyme component is protected from degradation by the organic solvents, i.e., encapsulation within reversed micelles, it is necessary to proceed in accordance with the invention.
• the first stage in the process is to prepare an aqueous solution in which the enzyme is dissolved and which contains an enzyme stabilizer.
• the desired amount of aqueous salt solution is prepared.
• the aqueous/glycol enzyme solution as procured from the manufacturer is mixed into the salt solution.
• Genetle agitation is used throughout the production process to thorougly mix all components. Violent agitation is to be avoided as it may actually degrade the enzymes by a physical shearing of the enzyme molecules).
• a first portion, such as one half, of the non-ionic surfactant is then gently mixed into the aqueous enzyme/salt solution so that the aqueous enzyme solution is dispersed therein. After thorough mixing is obtained, the remainder of the non-ionic surfactant is then added and thoroughly mixed in. At this stage, the aqueous enzyme/salt/surfactant mixture is a rather viscous clear liquid. If a hydrotrope such as glycol is used in the composition this is then added with continuous mixing. The hydrocarbon solvent is then gradually added to form the finished product.
• the final product is a clear transparent liquid, principally hydrocarbon solvent and surfactant and with less than 5% of water, and smaller amounts of enzyme and enzyme stabilizer.
• the clear liquid product may be packaged in any suitable container and stored for periods of several months and yet retain a good percentage of the enzyme activity. When used it is preferred to spray the product on the soiled fabrics a few minutes before placing them into a washing machine. Normal laundering procedures may be utilized. Of course, an effort should be made to spray the product directly on the visibly soiled portions of the fabric as direct contact will ensure full opportunity for attacking the oil/ grease, and/or protein, fat or starch stains prior to the laundering process.
• compositions were prepared wherein the enzyme content was varied from 0 up to 1.0%. These compositions were then tested for effectiveness against various types of stains, i.e., grass, ballpoint pen ink, dirty motor oil, and azocasein. Laundry detergent and a commercial pre-wash formulation, i.e., Clorox O pre-wash, were, in each instance, used for comparison purposes. Table II below sets forth the compositions. Tables III, IV and VII set forth the results of % stain removal as measured by instrument. Tables V, VI, and VIII set forth the results measured by visual grading (on a scale of 1-5, with 5 highest, 1 lowest).
• compositions set forth in Table IX above were stored for periods of time up to 2 months at storage temperatures varying between 3° and 37.5°C (35° and 100°F).
• the samples of the compositions were tested against both grass and azocasein stains at intervals up to the 2 months stated above.
• Table XIII below sets forth the results, thus indicating the enzyme stability in the compositions as a function of time and storage temperature.
• TABLE XV below presents some prewash formulations wherein several different enzymes were utilized. These formulations were also tested for performance on various stains. These samples were evaluated for performance on grass, blood and gravy. All three formulas provided a benefit on grass and gravy. The blood stain was totally removed by detergent alone. No enzyme stability test was conducted.
• compositions were prepared having further variations in formulation.
• Table XVI below sets forth a composition wherein additional enzyme stabilizer (triethanolamine - Formula F) was included.
• Table XVI also indicates the residual enzyme activity after storage for the stated period.

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• Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Detergent Compositions (AREA)
• Immobilizing And Processing Of Enzymes And Microorganisms (AREA)
• Enzymes And Modification Thereof (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)

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• 1985
  • 1985-08-23 CA CA000489369A patent/CA1263944A/en not_active Expired
  • 1985-09-02 DE DE8585306215T patent/DE3574483D1/de not_active Expired - Lifetime
  • 1985-09-02 AT AT85306215T patent/ATE48285T1/de active
  • 1985-09-02 EP EP85306215A patent/EP0177183B1/en not_active Expired
  • 1985-09-05 AU AU47103/85A patent/AU577148B2/en not_active Ceased
  • 1985-09-12 JP JP60200717A patent/JPS6172100A/ja active Pending
  • 1985-09-12 TR TR85/37851A patent/TR24582A/xx unknown
  • 1985-09-12 ES ES547587A patent/ES8700312A1/es not_active Expired
  • 1985-09-12 MX MX206600A patent/MX162714A/es unknown

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