GB2243615A - Beta-phase soap bars containing solubilized solid antibacterial agent - Google Patents

Abstract

Solid soap compositions for use as toilet detergents arc formed in the beta-phase from soaps preferably made from fat feedstock having a high Titer and a lower Iodine Value (I.V.). Preferred compositions contain a low level of moisture and a water-insoluble antibacterial agent (e.g. 3, 4, 4' trichlorocarbonilide (TCC)) solubilized in an organic solvent e.g. polyethylene glycol methyl ether for improved antibacterial effectiveness. The compositions form beta-phase more readily than those where the soaps are made from fatty feedstock having a high Titer and low I.V.. The beta-phase bars disclosed herein can be prepared at the surprisingly low moisture levels which provide improved degerming-antibacterial effectiveness.

Description

BETA-PHASE SOAP BARS INCLUDING THOSE CONTAINING LOW LEVEL OF MOISTURE AND SOLUBILIZED SOLID ANTIBACTERIAL AGENT TECHNICAL FIELD This invention relates to solid toilet detergent compositions containing soap in the beta-phase and, especially, to solid toilet detergent compositions that contain antibacterial agents.

BACKGROUND The use of antibacterial agents in soap bars is well known as documented in U.S. Pat. Nos. 3,835,057, issued Sept. 10, 1974; 4,490,280, issued Dec. 25, 1984; and 4,714,563, issued Dec. 22, 1987, all of said patents being incorporated herein by reference.

The said patents 3,835,057 and 4,490,280 also disclose the use of materials that will dissolve the antibacterial agents to improve the efficacy of the antibacterial agents. However, there is always a need to provide antibacterial compositions that are either more effective, or that use lower levels of antibacterial agents.

SUMMARY OF THE INVENTION The invention provides improved toilet detergent compositions in solid form containing beta-phase soap that is prepared preferably from high Titer, preferably low I.V. soap, and especially antibacterial detergent compositions, e.g., in the form of a bar comprising: A. from about 45% to about 94% soap (preferably alkali metal soap, more preferably sodium and/or potassium soap), of which at least about 50% (preferably at least about 60%, and more preferably at least about 75%) is in the beta-phase; B. from about 0.01% to about 4%, preferably from about 0.1% to about 1.5%, of antibacterial agent that is either water-insoluble or is low in water solubility; C. from about 2% to about 25% of solvent for said anti bacterial agent;; D. from 0% to about 30%, preferably from 0% to about 15%, more preferably from 0% to about 10%, of non-solvent synthetic detergent surfactant; E. from 0% to about 10%, preferably from about 1% to about 7%, more preferably from about 2% to about 5%, free fatty acid; F. from 0% to about 2%, preferably from about 0.1% to about 1.5%, more preferably from about 0.2% to about 1%, salt; and G. from about 3% to about 13%, preferably from about 4% to about 10%, more preferably from about 5% to about 8%, water.

DETAILED DESCRIPTION OF THE INVENTION The major ingredient of the compositions of this invention is alkali metal soap. The preferred compositions are of the type usually referred to as "toilet bars" which are the major product used to clean the skin. More especially, the compositions are skin cleansing antibacterial "deodorant" toilet bars, which are used to control odor and/or harmful bacteria on the skin.

SoaD The soap herein is primarily in the form of a beta-phase.

The formation of beta-phase soaps is well known and usually involves the use of high water, or organic solvent levels, and/or large amounts of milling or mechanical energy input. It has now been discovered that soaps derived from triglyceride feedstock (fats and/or oils) having: (1) a Titer of greater than about 42eC, preferably more than about 430 C, and more preferably greater than about 43.5*C; and (2) preferably, an Iodine Value (I.V.) between about 27 and about 34.25, more preferably between about 29 and 32, will form beta-phase soaps with less water, less organic solvent and/or less mechanical working. The soap bars of the invention have I.V.'s preferably less than 34.25, more preferably less than 32, most desirably less than 0.

The factorsThe soap bars of the invention have I.V.'s preferably less than 34.25, more preferably less than 32, most desirably less than 0. which determine fat quality are Titer and Iodine Value. A volume titled "Official and Tentative Methods of the American Oil Chemists' Society" containing the methods for running Titer and Iodine Value analyses, as well as methods for a large number of other analyses, is published by from the American Oil Chemists' Society, 35 E. Wacker Drive, Chicago, Illinois 60601.

The Method Number of Titer and Iodine Value are, respectively, A.O.C.S. Cc 12-59 and A.O.C.S. Cd 1-25.

Titer is a measure of the hardness or softness of fat. The hardness of fat varies. Each fat source has a characteristic composition and Titer. The Titer will vary to a small extent with individual animals and plants and with the location of the fat within the carcass or plant.

Hard fat makes firm soap, which does not become rancid quickly. Soft fat makes soft soap which is likely to become rancid unless the fat has been given an extra processing called "hydrogenation." The reason for this is that soft fat contains a larger percentage of "unsaturated" fatty acids.

To determine the Titer, soap is made by mixing the fat with potash which combines with the fatty acids to form a soap, setting the glycerin free. This potash soap is then mixed with dilute sulfuric acid which sets free the fatty acids. These free fatty acids are collected and cooled under specified conditions until they freeze. The temperature at which free fatty acids freeze is the Titer and is expressed in degrees Centigrade (C).

The Iodine Value (I.V.) is a measure of the unsaturation of fats and oils and is expressed in terms of the number of centigrams of iodine absorbed per gram of sample.

The I.V. of fat is another method of determining the hardness or softness of fats. To the soaper, I.V. and Titer analysis may both be used in blending fats for various soap brands. I.V. is an accurate measure of the hardness or softness and clearly identifies types of fats.

By actual numbers, the I.V. is in the reverse order to Titer: that is, the higher the I.V. number the lower the Titer and vice versa.

The terms "POS", "T", and "PKO" as used herein mean, respectively, palm oil stearin, tallow, and palm kernel oil.

Fat Physical Prooerties TABLE A POS Tallow PKO Titer 50.00 42.00 25.00 Iodine Value 35.00 49.50 18.00 TABLE B 95POS/5PKO 75POS/25PKO 70POS/30PKO Titer 48.75 43.75 42.50 Iodine Value 34.15 30.75 29.90 Beta-Phase at 6% Water Yes Yes Yes TABLE C 50POS/ 37.5POS/ 25POS/ 25T/ 37.5T/ 50T/ 75T/ 25PKO 25PKO 25PKO 25PKO Titer 41.82 40.86 39.90 37.97 Iodine Value 34.38 36.19 38.00 41.63 Beta-Phase at 6% Water No No No No The Titer and I.V. values of Table A are obtained from PORIM No. 13, I. Ahmad, Palm Oil Research Institute of Malaysia, (June 1984) for POS; Bailey's Fats and Oils, Vol. 1, Chapter 6, 4th Ed., for tallow and PKO. The Titer and I.V. values for Tables B and C are the weighted averages.

Soap bars made from the feedstocks in Table B, with sufficient mixing and milling, form beta-phase even at the low moisture level of 6%. The 75POS/25PKO feedstock is a preferred blend and is used to make the toilet bars of Examples 1, 2, 3, 4A, 5, and 8 herein. Bars made with the preferred feedstock which are not worked into the beta-phase do not indicate the same advantages as the beta-phase bars.

The soap bars of the invention have Titers preferably greater than 42.50C, more preferably greater than 430C, and desirably greater than 43.50C.

In general, beta-phase soaps usually contain at least about 15% water and require extensive mechanical working, e.g., milling the soap more than once. See U.S. Pat. No. 4,719,030, Williams, Dawson, and Medcalf, Jr., issued Jan. 12, 1988, at column 4, lines 10-12. However, the soaps described herein will go into the highly desirable beta-phase at low moisture levels, even down to about 3-5% moisture, and at higher moisture levels the amount of mechanical working is no more, and often less, than is required by any typical process that makes a milled bar.

A most unique aspect of the bars herein is the ability to form a beta-phase at low moisture levels. It has been found that the combination of beta-phase soap and low moisture level provides improved antibacterial action in toilet bars containing solubilized solid antibacterial agents. This same improvement is not found in bars containing: (1) large amounts of omega-phase soap and/or (2) high moisture levels. This surprising finding was made feasible by the use of the soaps herein since normally one cannot make a beta-phase soap with a low moisture level.

Another benefit of using the beta-phase is that the sudsing is improved, thus making it possible to use lower levels of free fatty acids, etc. for the purpose of increasing the "creaminess" of the foam. Lower levels of fatty acid are also helpful in making the beta-phase soap.

The fatty acid soaps herein are present at a level of from about 45% to about 94%, preferably from about 55% to about 90%, and more preferably from about 75% to about 85% by weight of the bar. In the bars of the present invention, the amount of betaphase soap is from about 50% to about 100%, preferably at least about 60%, more preferably at least about 75%, and even more preferably at least about 90%, by weight of the total soap portion of the bar.

Desirably, the soap is predominantly C16 and/or C18, e.g., mixtures of stearic, palmitic, and/or, less desirably, oleic acids. The bar is preferably a mixture of fatty acid soaps comprised of C16 and/or C18 soaps, and less than about 25%, preferably less than 20%, shorter chain soaps, e.g., C12 and/or C14.

Convenient sources of palmitic and/or stearic acids are, e.g., the high melting fractions of palm oil and/or tallow that are separated by winterizing said oils, e.g., "palm oil stearin." The content of lower molecular weight soaps and highly unsaturated soaps is preferably minimized as these soaps apparently interfere with the formation of the beta-phase soap that is needed for the purposes set forth herein.

The distribution of chain lengths is preferably such that stearate and/or palmitate is from about 40X to 80%, preferably from about 45% to about 70%, and more preferably from about 50% to about 65% by weight of the soap portion of the bar. The remainder can be a mixture of soaps such as laurate, myristate, (preferably) oleate, and/or linoleate so long as the feedstock has the required high Titer. The use of lower chain lengths and unsaturated soaps are limited for they inhibit the formation of the desired betaphase. Thus, limited amounts of laurates and myristates are desirable optional soaps for sudsing purposes and oleates can be tolerated at higher levels than other remainder soaps. However, care must be ta-ken to insure that the feedstock used has the required high Titer and preferably a low I.V. for the low moisture bars.Higher I.V.'s (over 34.25) can be used for higher moisture (15-35%) bars.

As discussed hereinafter, the presence of fatty acid inhibits the formation of beta-phase soap and the presence of water and/or the solvent for the antibacterial agent tend to favor the formation of beta-phase.

It is surprising that a toilet bar can be made in the betaphase without large amounts of milling, water, and/or polymer present. The use of fat feedstock having the preferred Titer to make the soaps is crucial to this result. Such bars are novel and highly desirable, even without the antibacterial agent present, and, without the antibacterial agent, the amount of water can then be higher, e.g., up to about 35%. The benefit when higher levels of water are present is that less work is required to form the beta-phase.

When the antibacterial agent and its solvent are not present, the maximum level of soap can be increased by the amount of those materials removed.

The cations in the soaps herein are the typical ones used in the formation of toilet bars. Sodium is the preferred cation, but sodium soaps can be used with up to about 40%, preferably less than about 20%, more preferably less than about 10%, of potassium soap for improved solubility and or processability. Higher levels of potassium will normally be used only in bars containing high levels of stearate. Other cations such as lithium and magnesium can be present.

Antibacterial Anent The antibacterial agent can be present at a level of from about 0.01% to about 4%, typically from about 0.1% to about 2%, and preferably from about 0.5% to about 1%. The level is selected to provide the desired level of antibacterial activity and can be modified as desired. The identity of the antibacterial agent is not part of the invention, but many antibacterial agents are not desirable for use on the skin and others are not benefited as much as the preferred agents described hereinafter. Many antibacterial agents are known to those skilled in the art and any agent that is not very soluble, as is also known in the art, and as disclosed in, e.g., U.S. Pat. Nos. 3,835,057 and 4,714,563, both incorporated hereinbefore by reference, can be used.

Suitable antibacterial agents include: 3,4,4'-trichlorocarbanilide (TCC); 3-trifluoromethyl-4,4'-dichlorocarbanilide (TFC); 2,2'-dihydroxy-3,3',5,5',6,6'-hexachlorodiphenylmethane; 2,2'-dihydroxy-3,3',5,5'-tetrachlorodiphenylmethane; 2,2' -dihydroxy-3,3' ,dibromo-5,5'-dichlorodiphenylmethane; 2-hydroxy-4,4'-dichlorodiphenylether; 2-hydroxy-4,2',4'-trichlorodiphenylether (TCS); 2-hydroxy-3,5',4-tribromodiphenylether; 2,6-dimethyl-4-hydroxychlorobenzene (PCMX); and 1-hydroxyl-4-methyl-6-(2,4,4-trimethylpentyl)-2(1H)-pyridinone (Octopirox).

The antibacterial agents preferably have solubilities of less than 500 ppm in 250C water, usually less than 100 ppm, and often less than 75 ppm. Preferred antibacterial agents include TCC, TFC, and TCS, and mixtures thereof. The most preferred antibacterial agent is TCC, which is insoluble in water (56 pub at 25it) and about 20% soluble in PEG.

If desired, the antibacterial agent can be omitted for the more general use toilet- bars discussed hereinbefore. Also, soap bars in the beta-phase that are prepared with different soaps also provide the increased antibacterial effectiveness.

Solvent for the Antibacterial Aaent Solvents for the antibacterial agent are known to those of ordinary skill in the art and are disclosed in the patents incorporated hereinbefore by reference.

Suitable solvents include: alkylphosphoramides such as hexamethylphosphoramide; alkylureas such as tetramethylurea; polyethylene glycols; mixtures of Cg-C22 fatty acids and polyethylene glycols; anionic-cationic complexes formed by mixing, if necessary with warming, amines and acids, preferably organic. (The amines can be aliphatic primary, secondary or tertiary amines or aliphatic or alkylaryl quaternary ammonium compounds. The amines should normally include a long chain fatty group and the total number of carbon atoms in the amine should prefer ably be at least 10. Preferred acids are straight chain carboxylic acids and the acid is preferably carboxylic acid, such as alkylethoxyacetic acid having the general formula R(OCH2CH2)nOCH2C02H where n is 1 to 25, preferably 1 to 10, and R is a long chain Cg-C22 group); phosphine oxides such as C6-C1o trialkylphosphine oxides; amine oxides such as C8-C18 alkyl, di-C1-C4-alkyl (or alkanol) amine-N-oxides; complexes formed from amine oxides and C2-Cg carboxylic acids such as acetic acid; and substituted ammoniumphosphates such as the salt formed between triethanolamine-6-EO and ortho- or pyrophosphoric acid.

More specific examples include: polyethyleneglycols such as polyethyleneglycol 600 M.W. and polyethyleneglycol 1,000 M.W.; polyethyleneglycol mono-esters such as polyethyleneglycol 400 M.W.

monol aurate; polyethyleneglycol ethers such as polyethyleneglycol (20)cetyl ether or PEG-350 monoethyl ether; glycerolalkoxylates such as glycerol 12 (mole) ethoxylate and glycerol 18 (mole) ethoxylate; tetra-alkylureas such as tetramethylurea; hexa-alkylphosphoramides such as hexamethyl phosphorami de; polyalkylpolyphosphoramides such as octamethylphrophosphoramide; amine oxides such as lauryldimethylamine-N-oxide; amine oxide carboxylates such as lauryldimethylamine-N-oxide acetate and lauryldimethylamine-N-oxide palm kernel car boxylate; amine oxide sulfonates such as lauryldimethylamine oxide/dodecyl benzenesul fonate; phosphine oxides such as tri-n-octylphosphine oxide and tri ethanol amine; triethanolamine alkoxylates such as triethanolamine polyethoxylate (6); triethanolamine ethoxylate complexes such as triethanolamine-6 ethoxyl ate acetate; triethanolamine-6-ethoxylate palm kernel (palm kernel fatty alcohol - PK) complexes such as triethanolamine-PK-6-ethoxylate lactate; triethanolamine-PK-6-ethoxylate succinate; triethanolamine-PK-6-ethoxylate citrate; triethanolamine-PK-6-ethoxylate benzoate; triethanolamine-PK-6-ethoxylate phthalate; and triethanolamine-PK-6-ethoxylate terephthal ate; mono-alkylamine ethoxylate complexes such as stearyl amine-lo-ethoxylate lactate; stearyl amine-lO-ethoxylate succinate; stearyl amine-lO-ethoxylate citrate; stearyl amine-lO-ethoxylate benzoate; stearyl amine-lO-ethoxylate phthalate; and stearyl amine-l0-ethoxylate terephthal ate; di-alkylamine complexes such as dicoconutamine palm kernel fatty acids (palm kernel carboxylate); tri-alkylamine complexes such as cetyldimethyl amine acetate; cetyldimethylamine palm kernel carboxylate; cetyidimethylamine stearate; cetyl dimethyl amine oleate; cetyldimethylamine glycol ate; cetyldimethylamine lactate; cetyidimethylamine succinate; cetyidimethylamine citrate; cetyidimethylamine benzoate; cetyldimethylamine phthalate; and cetyldimethyl amine terephthal ate; tri-alkylamine sulfonates such as cetyldimethylamine dodecyl benzene sul fonate; polyalkylenepolyamines such as polyethyleneimine 600; polyalkylenepolyamine alkoxylates such as diethylenetriamine-5-propoxylate and diethylenetriamine-20-propoxylate; quaternary ammonium alkane complexes such as cetyltrimethylammonium soap and cetylbenzyldimethylammonium soap.

The above solvents and others are suitable, but the preferred solvents are polyethylene glycols, ethoxylated fatty alcohols; block copolymers of ethylene oxide and propylene oxide; and mixtures thereof. The solvent is not required to be fluid at room temperature.

The level of the solvent is typically from about 2% to about 25%, preferably from about 3% to about 10%, more preferably from about 4% to about 8%. The level of the solvent is selected so that the antibacterial agent is solubilized in the composition and there are no antibacterial agent crystals present to promote the formation of additional crystals during storage. Solvents that are also surfactants are desirable. The solvent can also promote the formation of beta-phase soap and improve the processability of the composition when the proper solvent is selected.

Free Fattv Acid The free fatty acid is an optional, but highly desirable ingredient that is normally present at a level of from about 0.5% to about 10%, preferably from about 1% to about 7%, more preferably from about 1.5% to about 5%. The fatty acid improves the foam of the composition when it is primarily C12 and/or C14. The fatty acid also improves the processability of the composition when it is being formed into a toilet bar. If the level of free fatty acid and/or salt is too high and the level of water is too low as required to obtain optimum antibacterial effectiveness, then the excess free fatty acid may combine with the soap to form hardspecks that are very undesirable. The free fatty acids are typically those that are normally present in toilet bars and include the typical C8 to C18 fatty acids and especially those derived from coconut oil.

Salt The salt content of the composition should be kept low to promote the formation of the beta-phase. The salts include the typical ones found in such bars and include the alkali metal salts of, e.g., sulfuric and hydrochloric acids. The level should typically be from 0% to about 2%, preferably from about 0.1% to about 1.5%, more preferably from about 0.2% to about 1%.

Water The level of water in the compositions of the invention is critical to the optimum antibacterial effectiveness. The level is from about 3% to about 13%, preferably from about 4% to about 10% more preferably from about 5% to about 8%. Too little water can give hardspecks and poor processing.

Higher levels favor beta-phase formation and, when antibacterial agents are not present, the water level can, and desirably is, raised to, e.g., from about 15% to about 35%. The only real upper limit is the practical one set by the processability of the formula and the ability to maintain the level of water in the finished bars.

It is believed that excess water causes the formation of antibacterial agent crystals in the bar that are less effective than the solubilized antibacterial agent in the bar. It is also believed that the bars of this invention at higher moisture levels are improved bars over non-beta-phase bars at comparable moisture levels for antibacterial effectiveness and/or lather.

Using more solvent for the antibacterial agent can also improve the processing, but increases the probability of the formation of hardspecks. More solvent also can cause softer bars and can raise the level of expensive material that may not have a primary function.

The ratio of water to free fatty acid is typically from about 2:1 to about 5:1.

Optional Ingredients The compositions of the invention can optionally contain materials which are conventionally used in skin cleansing compositions.

Nonionic emollients can be included as skin conditioning agents in the compositions of the present invention at levels up to about 10%. Such materials include, for example, mineral. oils, paraffin wax having a melting point of from about 100ref to about 170"F, fatty sorbitan esters (see U.S. Pat. No. 3,988,255, Seiden, issued Oct. 26, 1976, incorporated by reference herein), lanolin and lanolin derivatives, esters such as isopropyl myristate and triglycerides such as coconut oil or hydrogenated tallow.

Fatty alcohols such as coconut alcohols can be included at levels up to about 10%.

Cationic and nonionic polymeric skin feel aids are useful ingredients in the compositions herein at levels of from about 0.2% to about 5% as disclosed in U.S. Pat. No. 4,820,447, issued Apr. 11, 1989, incorporated herein by reference. Reduced skin irritation benefits of both types of polymers are described in "Polymer JR for Skin Care" Bulletin, by Union Carbide, 1977. The cationics are preferred over the nonionics because they provide better skin feel benefits. Examples of the cationic polymers and the nonionic polymers useful for this purpose are set out below.

A particularly preferred skin feel aid is cationic (quaternized) guar gum, e.g., Jaguar C-14-S, from Celanese Corp.

Other types of high molecular weight polymeric skin feel agents, such as nonionic guar gums, Merquats 100 and 550, made by Merck & Co., Inc; UCARE Polymer JR-400, made by Union Carbide Corp.; Mirapol A15 made by Miranol Chemical Company, Inc.; and Galactasol 811, made by Henkel, Inc.; plus others, are usable.

The nonionic polymers found to be useful as skin feel aids include the nonionic polysaccharides, e.g., nonionic hydroxypropyl guar gums, offered by Celanese Water Soluble Polymers, a Division of Celanese Corp. A preferred nonionic hydroxypropyl guar gum material is JaguarS HP-60 having hydroxypropyl molar substitution of about 0.6. Another class of useful nonionics is the cellulosic nonionic polymers, e.g., hydroxyethylcellulose and carboxymethyl - cellulose.

Perfumes, dyes and pigments can also be incorporated into compositions of the invention at levels up to about 5%. Perfumes are preferably used at levels of from about 0.5% to 3% and dyes and pigments are preferably used at levels of from about 0.001% to about 0.5%.

The soap bars of this invention can contain up to 30% of a synthetic surfactant that is not a solvent for the antibacterial agent. If such a synthetic surfactant is included, a mild one is preferred. A mild synthetic surfactant is defined herein as one which does relatively little damage to the barrier function of the stratum corneum. The mild surfactant is preferably present in the present composition at a level of from 0% to about 15%, more preferably from 0% to about 10%. The fatty acid soap and mild, non-solvent surfactant mixture preferably has a ratio of from about 6:1 to about 37:1, preferably from about 10:1 to about 20:1 soap: synthetic.

Some preferred mild synthetic surfactants useful in this invention include alkyl glyceryl ether sulfonate (AGS), anionic acyl sarcosinates, methyl acyl taurates, N-acyl glutamates, alkyl glucosides, acyl isethionates, alkyl sulfosuccinate, alkyl phosphate esters, ethoxylated alkyl phosphate esters, alkyl ether sulfates, methyl glucose esters, protein condensates, mixtures of alkyl ether sulfates and alkyl amine oxides, betaines, sultaines, and mixtures thereof. Included in the surfactants are the alkyl ether sulfates with 1 to 12 ethoxy groups, especially ammonium and sodium lauryl ether sulfates. Alkyl chain lengths for these surfactants are Cg-C22, preferably C10-C18. The most preferred mild surfactant is sodium alkyl (preferably coconut) glycerylether sul fonate.

Other synthetic detergent surfactants that can be used include those disclosed in U.S. Pat. Nos.: 4,714,563, Kajs et al., issued Dec. 22, 1987; 4,493,785, Joshi, issued Jan. 15, 1985; and 4,861,508, Wegener et al., issued Aug. 29, 1989, all of said patents being incorporated herein by reference.

Preoaration of Toilet Bar ComDositions Processions SteDs The toilet bars of the present invention are preferably made by the milled soap process. This process typically comprises (1) drying neat phase soap which has a moisture content of about 28-32% down to a moisture content of 7-14%; (2) forming the dried soap into noodles by passing it through a plodder where the conversion from omega-phase to the beta-phase begins to occur; (3) mixing the various additives such as colorants, perfume, the predissolved antimicrobial agents, etc., into the soap noodles in an amalgamator or other suitable soap mixing equipment; (4) passing the mixture from (3) through a mill, or a series of mills, thereby forming "ribbons" of soap less than about 0.020 inches thick, preferably less than 0.015 inches thick, more preferably less than 0.010 inches thick, while maintaining a soap temperature below 40'C, preferably below 35etc, more preferably below 30it, and ensuring the conversion of the soap to predominantly ( > 50%) beta-phase; (5) passing the milled soap mixture from (4) through one, or more, plodders with temperature profiles about equal to that during milling to form a log of soap; and (6) cutting the log into segments and stamping the segments into the desired bar shape.

The antimicrobial agent must be predissolved before addition into the soap noodles. This is done by dispersing the antimicrobial agent into the liquid solvent. The mixture is mixed until the antimicrobial agent is completely dissolved (no visible trace of the antimicrobial). It is important to keep this mixture free from water, as water will precipitate the antimicrobial agent out of solution.

Phase Analysis of Soa Bars Soap phase is determined via X-ray diffraction. This is done through the measurement of the short spacings (d-spacings of 2.7 to 3.7 angstroms) observed in typical soap X-ray patterns and correlates with the average soap phase present in the bar (omega, beta, or delta). The ratio of phases is determined by the comparison of the optical density of the beta diffraction ring (dspacing of 2.76 angstroms) to that of the omega diffraction ring (d-spacing of 2.95 angstroms). The bar contains predominantly beta-phase ( > 50%) when the beta diffraction ring is greater than half as intense as the omega ring and is completely in the betaphase when no omega or delta bands are observed.

EXAMPLES The following examples and methods are illustrative and are not intended to limit the scope of the invention(s). All levels and ranges, temperatures, results, etc., used herein are approximations unless otherwise specified.

EXAMPLES 1-3 Ingredient 1 2 3 Sodium Palm Oil Stearinatea 62.65 60.87 56.25 Sodium Palm Kernelateb (PKO) 20.90 20.31 18.75 Water 6.18 8.55 14.73 PEG-6 Methyl Ether 4.35 4.35 4.35 Fragrance 1.32 1.32 1.32 Coconut Free Fatty Acid 2.25 2.25 2.25 Titanium Dioxide 0.80 0.80 0.80 Triclocarban (TCC) 0.75 0.75 0.75 Sodium Chloride 0.75 0.75 0.75 Tetrasodium EDTA 0.05 0.05 0.05 Totals 100.00 100.00 100.00 % Beta-Phase > 75% -100% -100% Degerming (Log Reduction)C 1.65 1.31 0.79 a Approximate fatty chain length distribution of the 75% POS soaps is: 5% sodium stearate; 61.5% sodium palmi tate; 2% sodium myristate; 26% sodium oleate; 6% sodium linoleate; etc.

b Approximate fatty chain length distribution of the 25% PKO soaps is: 48% sodium laurate; 15% sodium myristate; 8% sodium palmitate; 2% sodium stearate; 16% sodium oleate; 3% sodium linoleate; etc.

c The least significant difference at 95% confidence is 0.47.

The hand degerming protocol used is a slightly modified (no prescreening of panelist) Cade Handwashing procedure; Case, A.R., "A Method of Testing Degerming Efficiency of Hexachlorophene Soaps," Journal of the Society of Cosmetic Chemists, 2, 281-291 (1951), incorporated herein by reference.

The bars of Examples 1-3 are prepared using the above preparation. The levels of water are respectively 6.18%; 8.55%; and 14.73%. Note that the Degerming (Log Reduction) falls off in Examples 1-3 as the amount of water is respectively increased from 6.18% to 8.55% to 14.73%. The Degerming decreases as the water level increases.

The fat feedstock used to prepare the 75POS/25PKO soaps in Examples 1-3 has a Titer of about 43.75etc and an I.V. of about 30.75. The soap in Example 1 is more than about 75% in the beta-phase and in Examples 2 and 3 is essentially all beta-phase.

Table 1 shows the approximate fatty chain length distribution of the total 75POS/25PKO soaps used in of Examples 1, 2 and 3.

TABLE 1 75POS/25PKO Soaps Wt.% Laurate (C12) 12.23 Myristate (C14) 4.95 Palpitate (C16) 48.05 Stearate (C18) 4.18 Oleate (C18:1) 23.63 Linoleate (C18:2) 5.33 Miscellaneous 1.63 Total -100.00 Titer - 43.75'C I.V. - 3075 EXAMPLE 4 The Bars A and B below both contain a TCC/PEG degerming system at comparable levels. Bar A has lower salt and lower free fatty acid than Bar B. The feedstock Titers for Bars A and B are, respectively, 43.75etc vs. 33.650C. At least about 75% of the soap of Bar A is in beta-phase. Less than 50% of Bar B is beta-phase.

Bar B shows hardspecks after storage. Bar A shows little or no hardspecks after storage.

EXAMPLE 4 (Continued) Bar A Bar B Inqredient (Wt.%) (Wt%) Sodium Palm Oil Stearinate 62.55 Sodium Tallowate - 38.71 Sodium Palm Kernel ate 20.90 38.71 Water 6.18 5.35 PEG-6 Methyl Ether 4.35 5.00 Fragrance 1.32 1.32 Coconut Free Fatty Acid 2.25 7.90 Titanium Dioxide 0.80 0.80 Triclocarban (TCC) 0.75 0.75 Sodium Chloride 0.75 1.41 Tetrasodium EDTA 0.05 0.05 Totals 100.00 100.00 Bar Feel* Initial 800F (26.7'C) 10 10 90'F-(32.2'C) 10 10 1 Month 80"F 9 6 90F 9 5 2 Month 800F 10 6 90*F 10 5 3 Month 80F 9 4 900F 9 4 *Bars are stored at 50F (100C). Bar feel is evaluated by the following protocol two hours after bars are removed from 500F storage. The bar feel grades of Example 4 show that Bar A remains smooth and essentially free of the formation of hardspecks, while Bar B develops hardspecks.

Bar Feel Protocol Place dishpan under dual-hot-cold water tap. Adjust water flow to about 800F (26.7it); fill dishpan with water at this temperature; and allow water to continuously overflow pan. Wash bar with both hands for one minute in the pan near the water inlet, but not directly under it. This treatment removes surface roughness and sharp edges. Then revolve the bar in one hand for 10 seconds while feeling for dragginess or areas of sandiness or roughness, as well as for individual large hardspecks. Using the feel-impression generated during the 10 second wash period, grade the bar using the scale below.

Grade the bar with the number that most nearly describes the feel of the sample. If the bar exhibits two types of defects of unequal severity, report the number based on the worst fault.

Bar Feel Grading Scale 10 Perfectly smooth and slippery 9 Practically smooth or one speck 8 Barely detectable sandiness, roughness, dragginess, or 2-3 specks 7 Slight sandiness, roughness, dragginess, or 4-5 specks 6 Moderate overall sandiness, roughness, dragginess, or 6-10 specks 5 Quite noticeable overall sandiness, roughness, draggi ness, or 10-20 specks 4 Pronounced overall sandiness, roughness or more than 20 specks 3 Pronounced overall coarse sandiness or roughness (like LAVA) 2 Extreme overall coarse sandiness or roughness 1 Extreme overall abrasive roughness EXAMPLES 5 AND 6 In Examples 5 and 6 below, the Degerming bar of Example 5 is compared with that of a leading, commercially available Degerming bar having an approximate formulation as set out as Example 6.

Example 6 is a predominantly omega-phase bar with its soap made from fats having a weighted average Titer of about 40.05, and a weighted average I.V. of about 45.41. Note that Example 5 of this invention is surprisingly a superior degermer than Example 6: 1.65 vs. 0.95, notwithstanding the use of less TCC. Also note that Example 5 is a superior lathering bar over Example 6. The Lather Volume and Creaminess protocol is set out below. Higher lather grades are better.

Lather Volume and Creaminess 1. Rotate bar 3 times in both hands.

2. Add a little water, rub both hands 5 times.

3. Rotate 3 times, grade for Flash Volume.

4. Rotate 4 times, grade for Flash Creaminess.

5. Rotate 3 times, grade for Ultimate Volume.

6. Rotate 10 times, grade for Ultimate Creaminess.

Load Soil Lather 1. Put 0.2 cc of soil on hands, rub in well.

2. Rotate bar 3 times in both hands.

3. Add a little water, rub both hands 5 times.

4. Rotate 3 times, grade for Flash Load Volume.

5. Rotate 7 times, grade for Ultimate Load Volume.

Conditions: 95-1000F (-37'C) city water.

The hand degerming protocol used is a slightly modified (no prescreening of panelist) Cade Handwashing procedure; Case, A.R., "A Method of Testing Degerming Efficiency of Hexachlorophene Soaps," Journal of the Society of Cosmetic Chemists, 2, 281-291 (1951), incorporated herein by reference.

Example 5 of this invention is a superior latherer, as well as a superior degermer to Example 6.

Formulas of Examples 5 & 6 Ingredient Ex. 5 Ex. 6* Sodium Palm Oil Stearinate (POS) 62.65 Sodium Tallowate (PKO) - 71.22 Sodium Palm Kernel ate 20.90 10.61 Water 6.18 10.00 PEG-6 Methyl Ether 4.35 4.44 Glycerin - 0.43 Fragrance 1.32 1.50 Coconut Free Fatty Acid 2.25 0.30 Titanium Dioxide 0.80 0.10 Triclocarban (TCC) 0.75 0.84 Sodium Chloride 0.75 0.46 Tetrasodium EDTA 0.05 0.10 Totals 100.00 100.00 % Beta-Phase > 75% < 50% Degerming (Log Reduction)** 1.65 0.95 * Approximate formulation of a leading commercial soap bar.

** Significant difference at 95% confidence.

Lather Results Lather Ex. 5 Ex. 6 Flash Volume 7.5-8.0 6.0 Ultimate Volume 7.5-8.0 6.0 Flash Volume-Soil 5.0-6.0 3.5 Ultimate Volume-Soil 5.5-6.5 3.5 Flash Creaminess 8.0-8.5 7.0 Ultimate Creaminess 8.0-8.5 7.0 The Degerming bar, Example 5, is compared with that of a leading, commercially available Degerming bar, Example 6. Example 6 is a predominantly omega-phase bar with its soap made from fats having a weighted average Titer of about 40.05, and a weighted average I.V. of about 45.41. Example 5 of this invention is surprisingly a superior degermer than Example 6: 1.65 vs. 0.95, notwithstanding the use of less TCC degermer. Example 5 is also a superior lathering bar over Example 6.

Claims (10)

1. Improved antibacterial toilet detergent composition in then form of a bar comprising: (A) from about 45% to about 94% alkali metal soap that is at least about 50sue in the beta-phase, and wherein from about 47% to about 80% of said soap is derived from fatty feedstock having a weighted average Titer of at least about 420C and a weighted average Iodine Value (I.V.) of from about 27 to about 34.25; (B) from about 0.01% to about 4% of antibacterial agent that is either water-insoluble or has only limited water solubility; (C) from about 2% to about 25% of solvent for said anti bacterial agent; (D) from 0% to about 30% of non-solvent synthetic detergent surfactant; (E) from 0% to about 10% free fatty acid; (F) from 0% to about 2% salt; and (G) from about 3% to about 13% water.

2. The composition of Claim 1 wherein said soap (A) is present at a level of from about 55% to about 90%, ; said antibacterial agent (B) is present at a level of from about 0.5% to about 2.0%; said solvent (C) is present at a level of from about 3% to about 10%; said free fatty acid (E) is present at a level of from about 1% to about 7%; and said water (G) is present at a level of from about 4% to about 10%.

3. The composition of Claim 2 wherein said soap (A) is at least about 75% in the beta-phase and said Titer is at least 42.5it and said I.V. is from about 29 to about 32 and about 75% of said soap is in said beta-phase; and wherein the level of said water (G) is from about 5% to about 8%; and wherein said antibacterial agent (B) is trichlorocarbanilide.

4. The composition of Claim 2 wherein said soap is present at a level of from about 75% to about 85%; said free fatty acid (E) is predominantly C12 and/or C14 fatty acids at a level of from about 1.5% to about 5%; and said water (G) is present at a level of from about 5% to about 8sue.

5. The composition of Claim 4 wherein said antibacterial agent is selected from the group consisting of 3,4,4'-trichlorocarbanilide (TCC); 3-trifluoromethyl-4,4'-dichlorocarbanilide (TFC); 2-hydroxy-4,2',4'-trichlorodiphenylether (TCS); and mixtures thereof.

6. The composition of Claim 5 wherein said antibacterial agent is at least predominantly 3,4,4'-trichlorocarbanilide (TCC).

7. The composition of Claim 1 wherein the soap in the bar is at least about 75% in the beta-phase and the said water (G) is present at a level of from about 4% to about 10%.

8. The composition of Claim 7 wherein said water (G) is present at a level of from about 5% to about 8%.

9. The composition of Claim 1 wherein said antibacterial agent is selected from the group consisting of 3,4,4'-trichlorocarbanilide (TCC); 3-trifluoromethyl-4,4'-dichlorocarbanilide (TFC); 2-hydroxy-4,2',4'-trichlorodiphenylether (TCS); and mixtures thereof.

10. The composition of Claim 9 wherein said antibacterial agent is at least predominantly 3,4,4'-trichlorocarbanilide (TCC), and wherein said solvent (C) is present at a level of from about 3% to about 10%, and wherein said solvent is selected from the group consisting of polyethylene glycol; ethoxylated fatty alcohols; block copolymers of ethylene oxide and propylene oxide; and mixtures thereof.