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
  • C11D17/00—Detergent materials or soaps characterised by their shape or physical properties
  • C11D17/0047—Detergents in the form of bars or tablets
  • C11D17/006—Detergents in the form of bars or tablets containing mainly surfactants, but no builders, e.g. syndet bar
• • 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
  • C11D10/00—Compositions of detergents, not provided for by one single preceding group
  • C11D10/04—Compositions of detergents, not provided for by one single preceding group based on mixtures of surface-active non-soap compounds and soap
  • C11D10/042—Compositions of detergents, not provided for by one single preceding group based on mixtures of surface-active non-soap compounds and soap based on anionic surface-active compounds and soap
• • 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
  • C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
  • C11D1/02—Anionic compounds
  • C11D1/04—Carboxylic acids or salts thereof
  • C11D1/10—Amino carboxylic acids; Imino carboxylic acids; Fatty acid condensates thereof
• • 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
  • C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
  • C11D1/02—Anionic compounds
  • C11D1/12—Sulfonic acids or sulfuric acid esters; Salts thereof
  • C11D1/126—Acylisethionates
• • 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
  • C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
  • C11D1/02—Anionic compounds
  • C11D1/12—Sulfonic acids or sulfuric acid esters; Salts thereof
  • C11D1/14—Sulfonic acids or sulfuric acid esters; Salts thereof derived from aliphatic hydrocarbons or mono-alcohols
• • 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
  • C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
  • C11D1/02—Anionic compounds
  • C11D1/12—Sulfonic acids or sulfuric acid esters; Salts thereof
  • C11D1/16—Sulfonic acids or sulfuric acid esters; Salts thereof derived from divalent or polyvalent alcohols

Definitions

• TECHNICAL FIELD This invention relates to personal cleansing bars based on synthetic surfactants and to processes of making them.
• Synthetic surfactant-based personal cleansing bars have attracted much interest recently because they can be selected to 5 be milder to the skin than soap-based products. This mildness, however, comes with negatives to both the manufacturer and the consumer.
• the bar soap manufacturer experiences difficult processability due to the sticky nature of such products, as well as high raw material costs.
• the consumer experiences the negative ° performance properties of poor lather, messy smear, bar softness, and, consequently, high wear rates.
• the low melting point of the wax employed would cause a substantial soil load on the lather potential and result in poor lather volumes.
• One object of this invention is to provide a personal cleans ⁇ ing syndet bar composition which exhibits improved lather and reduced bar messiness, while not sacrificing the processability of the syndet bar.
• This invention relates to an improved processable, mild personal cleansing syndet bar comprising: at least about 10% by weight long chain C15-C 2 alkyl sulfate having essentially satu ⁇ rated, preferably Ci6-Cj8, alkyl chains, soap, free fatty acid, a lathering mild surfactant comprising C12-C14 alkyl isethionate, and a selected paraffin wax.
• the bar has improved bar messiness without a meaningful lather negative.
• a mild synthetic surfactant-based (syndet) bar with improved processability, good lather and/or reduced messiness (smear) is indeed an advance in this art.
• the present invention provides such an improved syndet bar comprising: (1) from about 10% to about 40%, preferably from about 15% to about 35%, of Ci5-C22 > preferably C15-C18, essentially saturated long chain alkyl sul- fates; (2) from about 15% to about 40%, preferably from about 18% to about 35%, of mild, high lathering, synthetic surfactants with at least about 10% by weight of the bar being C12-C1 alkyl isethionate; (3) from about 8% to about 25%, preferably from about 10% to about 20%, of C ⁇ o-C22» preferably C12-C18, essentially saturated fatty acids; (4) from about 2% to about 15%, preferably from about 3% to about 12%, C ⁇ o-C22 > preferably C12-C18, alkali
• a synbar comprising two separate components: the matrix and the actives.
• the matrix provides the physical charac ⁇ teristics (processability and bar messiness) while the actives provide lathering and mild properties.
• the matrix if not chosen correctly, can impede lather generation, cause poor bar feel, increase or decrease wear rate beyond an acceptable level, and/or reduce product mildness.
• the actives must be chosen so as to provide acceptable levels of lathering without negatively impacting mildness, a trade-off in formulations.
• bar matrix plasticizer materials such as triglycerides, fatty alcohols, etc., which tend to form a sufficiently plastic matrix, but also tend to depress lather potential.
• Other commonly used additive matrix materials such as salts, polysaccharides, etc., tend to make an overly brittle and water-soluble matrix that induces poor bar messiness performance.
• syndet bar means that the "bar” has more synthetic surfactant than soap unless otherwise specified.
• AS syndet bar means a syndet bar containing alkyl sulfate surfactant or its equivalent, unless otherwise specified.
• long chain means C15 and C22 > preferably Ci6-C20 > and mixtures thereof.
• C12-C14 alkyl and cocoyl as used herein are synonymous.
• the percentages, ratios, and parts herein are on a total composition weight basis, unless otherwise specified. All levels and ranges herein are approximations unless otherwise specified.
• An essential element of the present invention is the surfac ⁇ tant system.
• the long chain alkyl sulfate (hereinafter including its long chain equivalent synthetic surfactants) is key and is defined herein, as comprising Ci6-Cj8 alkyl chains at a level of at least about 90%, preferably about 93%, and more preferably about 97%.
• the long chain alkyl sulfate (and its equivalents) is derived from corresponding saturated straight chain alcohols.
• the preferred alkyl sulfate has a ratio of Cj ⁇ - is alkyl chains in the range of from about 100% Cie to about 100% Cis by weight.
• a commercially available Ci ⁇ -Cis alkyl sulfate is SIPON ® EC-Ill (formerly SIPEX ® EC-Ill), sodium cetearyl sulfate, which is approximately 60% Ci6 and 36% Cis- SIPON ® EC-Ill is sold by Alcolac Company, Baltimore, MD 21226.
• Another source is Henkel Corp., Ambler, PA 19002.
• Henkel 's sodium cetearyl sulfate, LANETTE E is an estimated 50-50% Ci ⁇ -Cis alkyl sulfate sold as an emulsifier.
• long chain surfactants which are equivalents to the long chain alkyl sulfate (mostly insoluble) could serve as either full or partial replacements for the long chain alkyl sulfate.
• long chain isethionates examples include long chain isethionates, sarcosinates, glyceryl ether sulfonates, etc.
• the acyl esters of isethionic acid salts, with esters of Ci ⁇ -Cis acyl isethionates and no more than 25% or lower C1 acyl groups are also useful.
• Preferred is stearoyl isethioniate with C143%; Cj ⁇ 50%; and Cis 47%.
• surfactant mildness can be measured by a skin barrier destruction test which is used to assess the irri- tancy potential of surfactants. In this test the milder the surfactant, the lesser the skin barrier is destroyed. Skin barrier destruction is measured by the relative amount of radio- labeled water ( 3 H-H2 ⁇ ) which passes from the test solution through the skin epidermis into the physiological buffer contained in the diffusate chamber. This test is described by T.J. Franz in the J. Invest. Dermatol.. 1975, 64, pp. 190-195; and in U.S. Pat. No. 4,673,525, Small et al .
• 3 H-H2 ⁇ radio- labeled water
• AGS alkyl glyceryl ether sulfonate
• the present invention contains a mild lathering surfactant at a level of from about 15% to about 40%, preferably from about 18% to about 35%_
• a high lathering or lather enhancing surfactant especially milder ones, are: C12-C14 alkyl isethio ⁇ nate; sodium lauroyl sarcosinate, C12-C14 alkyl glyceryl ether sulfonate.
• a "high lathering surfactant” as defined herein, is one which lathers better than the long chain Ci ⁇ -Cis alkyl sulfate.
• a "mild surfactant” as defined herein is one that is milder than sodium dodecyl sulfate.
• surfactants in general are disclosed in the patents incorporated herein by reference. They include limited amounts of anionic acyl sarcosinates, methyl acyl taur- ates, N-acyl glutamates, acyl isethionates, alkyl sulfosuccinates, alkyl phosphate esters, ethoxylated alkyl phosphate esters, tride- ceth sulfates, protein condensates, mixtures of ethoxylated alkyl 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 chains for these other surfactants are
• Cio-Cis- Alkyl glycosides and methyl glucose esters are preferred mild nonionics which may be mixed with other mild anionic or amphoteric surfactants in the compositions of this invention.
• the bars of this invention can have up to about 10% of high lathering, non-mild or shorter chain or traditional (coconut) alkyl sulfates and still maintain the mildness requirement of the bar.
• a preferred syndet bar contains a mixture of C12-C1 alkyl isethionate (SCI) and sodium lauroyl sarcosinate in a ratio of from about 1:1 to about 3:1, preferably from about 1.5:1 to about 2.5 : 1 .
• the primary plastic binders of the present invention are: (1) free fatty acid and (2) paraffin wax.
• the fatty acid material which is desirably incorporated into the present invention includes material ranging in hydrocarbon chain length of from abut 10 to about 22, essentially saturated. These fatty acids may be highly purified individual chain lengths and/or crude mixtures such as those derived from fats and oils.
• the preferred composition is lauric and stearic acids in a ratio of from about 1:3 to about 3:1, more preferably from about 1:2 to about 2.5:1.
• the composition may include soaps derived from hydrocarbon chain lengths of from about 10 to about 22, essentially saturated. It is preferred that the soap be the sodium salt, but other soluble soap can be used. Potassium, ammonium, triethanolammo ⁇ nium, and mixtures thereof, are deemed acceptable.
• the soaps are preferably prepared by the in situ saponification of the corres ⁇ ponding fatty acids, but they may also be introduced as preformed soaps. "Insoluble" soaps, e.g., magnesium and zinc soaps, are not included in the 2-15% level of "soap" in the composition defi ⁇ nition. However, insoluble soaps can be used as non-lathering, non-soil-load diluents.
• An important component of this invention is a wax having a melting point (M.P.) of from about 130'F to about 180'F (54'- 82'C), preferably from about 140'F to about 165'F (60'-74'C), and most preferably from about 142'F to about 160'F (6r-71'C).
• M.P. melting point
• a preferred paraffin wax is a fully refined petroleum wax which is odorless and tasteless and meets FDA requirements for use as coatings for food and food packages. Such paraffins are readily available commercially.
• a suitable paraffin can be obtained, for example, from The National Wax Co. under the trade name 6975.
• the paraffin preferably is present in the bar in an amount ranging from about 10% to about 40% by weight.
• the paraffin ingredient is used in the product to impart skin mildness, plas ⁇ ticity, firmness, and processability. It also provides a glossy look and smooth feel to the bar.
• the paraffin ingredient is optionally supplemented by a microcrystalline wax.
• a suitable microcrystalline wax has a melting point ranging, for example, from about 140'F (60 * C) to about 185'F (85'C), preferably from about 145'F (62'C) to about 175"F (79'C).
• the wax preferably should meet the FDA requirements for food grade microcrystalline waxes.
• a very suitable micro ⁇ crystalline wax is obtained from Witco Chemical Company under the trade name Multiwax X-145A.
• the microcrystalline wax preferably is present in the bar in an amount ranging from about 0.5% to about 5% by weight.
• the microcrystalline wax ingredient imparts pliability to the bar at room temperatures.
• Auxiliary plastic binders may be incorporated into the bar at levels of from 0% to about 10%. These binders may be selected from monoglycerides, polyethylene glycols, fatty alcohols, sugars, tallow alcohol ethoxylates, and mixtures thereof. Other plastic binders are identified in the published literature, such as J. Amer. Oil Chem. Soc. 1982, 59, 442. The binder system can contain several plasticizers.
• the syndet bar of this invention may comprise 0% to about 5% of a suitably fast hydrating cationic polymer.
• the polymers have molecular weights of from about 1000 to about 3,000,000.
• the cationic polymer is selected from the group consisting of: (I) cationic polysaccharides; (II) cationic copolymers of saccharides and synthetic cationic monomers, and (III) synthetic polymers selected from the group consisting of:
• members of the cationic polysaccharide class include the cationic hydroxyethyl cellulose JR 400 made by
• members of the class of copolymers of saccharides and synthetic cationic monomers include those composed of cel- lulose derivatives (e.g., hydroxyethyl cellulose) and N,N-di- allyl ,N-N-dialkyl ammonium chloride available from National Starch
• the cationic synthetic polymers useful in the present in ⁇ vention are cationic polyalkylene imines, ethoxypolyalkylene imines, and poly[N-[-3-(dimethylammonio)propyl]-N'-[3-(ethylene- oxyethylene dimethylammonio)propyl]urea dichloride] the latter of which is available from Miranol Chemical Company, Inc., under the trademark of Miranol A-15, CAS Reg. No. 68555-36-2.
• Preferred cationic polymeric skin conditioning agents of the present invention are those cationic polysaccharides of the cationic guar gum class with molecular weights of 1,000 to 3,000,000. More preferred molecular weights are from 2,500 to 350,000. These polymers have a polysaccharide backbone comprised of galacto annan units and a degree of cationic substitution ranging from about 0.04 per anhydroglucose unit to about 0.80 per anhydroglucose unit with the substituent cationic group being the adduct of 2,3-epoxypropyltrimethyl ammonium chloride to the natural polysaccharide backbone. Examples are JAGUAR C-14-S, C-15 and C-17 sold by Celanese Corporation. In order to achieve the benefits described in this invention, the polymer must have characteristics, either structural or physical which allow it to be suitably and fully hydrated and subsequently well incorporated into the soap matrix.
• perfumes can be used in formu ⁇ lating the skin cleansing products, generally at a level of from about 0.1% to about 1.5% of the composition.
• Alcohols, hydro- tropes, colorants, and fillers such as talc, clay, calcium car ⁇ bonate and dextrin can also be used.
• Cetearyl alcohol is a mixture of cetyl and stearyl alcohols.
• Preservatives e.g., sodium ethylenediaminetetraacetate (EDTA), generally at a level of less than 1% of the composition, can be incorporated in the cleansing products to prevent color and odor degradation.
• Anti- bacterials can also be incorporated, usually at levels up to 1.5%.
• the following patents disclose or refer to such ingredients and formulations which can be used in the soap/synbars of this inven- tion, and are incorporated herein by reference:
• the syndet bars of this invention have a pH of from 4 to 9 in a 1% aqueous solution.
• the preferred pH is from 5 to 8, more preferably about 6.5 to 7.5.
• the Matrix Ratio Table shows the broad, preferred and more preferred levels and ratios of the several key ingredients.
• the bars of the present invention can have long chain alkyl sulfate at a level of 10-40% by weight of the bar and lathering mild synthetic surfactant at a level of 15-40% by weight of the bar.
• Their broad and preferred ratio ranges are, respectively, 2.5:1-0.3:1 and 2:1-0.4:1.
• Their more preferred and exemplified ratios are found in Examples 6 and 7 and are, respectively, 0.6:1/0.5:1.
• Matrix Ratio Table Another example of a reading of the Matrix Ratio Table is the lathering mild synthetic surfactant and paraffin which, respectively, have broad and preferred ratios of 4:1-0.4:1 and 2.5:1-0.5:1. In Examples 6 and 7, their ratios are, respectively, 1.7:1 and 0.9:1.
• All series of testing should include control, and all samples should be run in duplicates. A maximum of 7 products (6 plus a control) can be tested at one time, and an interval of 10 minutes between every 4 samples should be allotted for the addition of water as to not allow any products a lag time for soaking longer than 2 hours. Bar Soap Handwash Lather Volume Test
• the handwash lather test is used to provide in-use lather volume measurements for the lather performance of skin cleansing bars.
• the test measures both the ultimate lather volume generated and the volume which is generated after a very short lathering period (to reflect lathering ease).
• the lather volumes are generated under soil-loaded conditions.
• Synthetic soil is used for the soil-loaded lather volume test reported herein. Its formula and procedure for making it are set out below.
• the water source should be medium hardness (6-9 grain/gallon) for most testing, although water of lower and higher hardness can be used for special purposes.
• Target volume 3 Slightly lower than target
• the AGS paste can be at ambient temperature or preheated to 150 ⁇ F (65"C).
• the crutcher mix is dried and cooled using a combination flash chamber and chill roll or chill belt.
• the crutcher mix is first heated to approximately 300'F (149'C) by a heat exchanger and then flash dried in a chamber above the chill roll or chill belt. From the flash chamber the hot, dried mix is extruded onto the chill roll or chill belt.
• the chill belt or chill roll provides a uniform, thin, cool (85-95'F, 29-35'C) product in flake or chip form. Typical moisture for the flake is 1-10%, preferably about 2-4.5%.
• the ways to regulate the moisture in the order of preference, are (1) increasing or decreasing steam pressure on the heat exchanger; (2) increasing or decreasing crutcher mix rate to the heat exchanger; and (3) increasing or decreasing crutcher mix temperature to the heat exchanger. Amalgamating
• the flakes are weighed and mixed in a batch amalgamator to obtain uniform flake size. Preweighed perfume is added to the flakes and mixed in the amalgamator to obtain the desired finished product perfume level. The perfumed flakes are transferred to the mix hopper or directly to the plodder. Milling
• the 3-roll soap mills are set up with the first roll at 120'F (49'C) and the other two mills at about 44'F (7'C).
• the material is passed through the mills several times to provide a homogeneous mixture of perfume and dried flakes.
• the plodder is set up with the barrel temperature at about 115'F (46'C) and the nose temperature at 114-122'F (45-50'C).
• the ideal plodder is a dual stage plodder that allows use of a vacuum of about 15-25 inches of Hg.
• the plugs should be cut in 5" sections and stamped with a cold die block using die liquor such as alcohol, if appropriate.
• the level of the water in the above syndet bars stabilizes upon storage from about 3.75% to about 2%-3%.
• Comparative Experimental Formula A is the control bar for assessing lather and/or smear of the bar of this invention.
• Comparative Formula A is typical of an alkyl sulfate-based product disclosed in commonly assigned, copending U.S. Pat. Application Ser. No. 07/605,614, supra.
• Formulas 1 through 7 described below have improved smears compared to Comparative Formula A, without sacrificing processability. In some cases of Formulas 1 through 7, the lather volume has been reduced, these are included to teach the scope of the patent.
• Acceptable soil lather grades are those that are of magnitude 3.0 or greater.
• FORMULAS 1-3 Formula 1 demonstrates the large improvement in smear (lower numbers) upon incorporation of 21% paraffin wax relative to Comparative Formula A. See bottom of Table 3. Formulas 1-3 demonstrate the surprising benefit that paraffin waxes can impart to syndet bars containing long chain alkyl sulfates. Formula 2 further demonstrates that paraffin wax of a higher melting point (155'F/69'C) than that used in Formula 1 still provides an improved smear but without the large detriment to lather that the lower melting point (135 * F/59 * C) paraffin imparted to Formula 1. Formula 3 contains a mixture of the two paraffins which demon- strate intermediate properties between Formulas 1 and 2.
• Formulas 4 through 6 demonstrate the effects of auxiliary plasticizers such as polyethylene glycol (PEG) on the paraffin- containing long chain alkyl sulfate matrix.
• PEG polyethylene glycol
• Formula 4 has lower (better) smear (3.3/1.6 vs. 3.8/1.7) than Formula 2, the dif ⁇ ference being the presence of PEG in Formula 2.
• This smear improvement is achieved with no detriment to lather volume (3.0/3.0).
• Formulas 5 and 6 differ in a similar way: Formula 6 (no PEG) has better smear than Formula 5; surprisingly, Formula 6 actually has improved lather as well.
• FORMULA 7 Formula 7 demonstrates that lather can further be improved by increasing the level of high lathering synthetic surfactants (Form.
• Example I is a highly preferred personal cleansing bar of the present invention. It is the same as Formula 6, except that sodium cocoyl isethionate (SCI) is used in place of sodium coco ⁇ glycerylether sulfonate (AGS).
• SCI sodium cocoyl isethionate
• AGS sodium coco ⁇ glycerylether sulfonate
• Example II is similar to Example I, but 5% less cocoyl isethionate is used and 5% sodium isethionate is used.
• Example III is also similar to Example I, but a mixture of lauric and coconut fatty acids is used, and less lauric acid is used.
• Examples I-1II retain all of the advantages of Formula 6, but replacing the AGS with SCI results in a bar with substantially improved processability. Specifically, the product is a little softer during extrusion, flakes are more friable, and the product (bar) is slightly less sticky. The next of these differences is improved processability and an improved personal cleansing bar.

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• 1992
  • 1992-01-31 HU HU9302648A patent/HUT65146A/hu unknown
  • 1992-01-31 CA CA002105086A patent/CA2105086A1/en not_active Abandoned
  • 1992-01-31 WO PCT/US1992/000802 patent/WO1992016610A1/en not_active Application Discontinuation
  • 1992-01-31 JP JP4510174A patent/JPH06506260A/ja active Pending
  • 1992-01-31 AU AU18771/92A patent/AU1877192A/en not_active Abandoned
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  • 1992-01-31 EP EP92917282A patent/EP0646169A1/de not_active Withdrawn
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  • 1992-03-13 AR AR92321928A patent/AR244797A1/es active
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• 1993
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