SYNTHETIC DETERGENT BARS

Abstract

A bar composition comprising: a) 10%-60% synthetic (non-soap) surfactant; b) 0%-50% fatty acid and soap wherein total fatty acid soap is less than 60% of total synthetic surfactant; c) 6.8%-54% water-soluble structurant, selected from polyalkylene oxides having MW 1,500-10,000, PEO-PPO blockcopolymers, wherein the water soluble structurant has a melting point of 40-100 C. and further comprises polyalkylene oxides having MW 50,000-500,000, 1-5 wt %; d) 0.1%-4.8% alkali metal isethionate; e) 2.7%-13.5% water, wherein the sum of water, alkali metal isethionate and water-soluble structurant is 10%-60%, wherein based on the total amount of water, alkali metal isethionate and said water-soluble structurant, water is present 4-27%, alkali metal isethionate is present less than 8%, water-soluble structurant is present 68-90%. Use of the composition for eliminating efflorescence.

Claims

1. A bar composition comprising: a) 10% to 60% by wt. total bar synthetic non-soap surfactant; b) 0% to 50% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total synthetic surfactant; c) 6.8% to 54% water-soluble structurant, selected from of the group consisting of polyalkylene oxides having a MW of 1,500-10,000, polyethylene oxide polypropylene oxide block copolymers, mixtures thereof and wherein the water soluble structurant further comprises polyalkylene oxides having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5% based on the weight of the composition, wherein the amount is encompassed in the amount of water soluble structurant of 6.8 to 54%, wherein the water-soluble structurant has a melting point of 40 to 100 C.; d) 0.1% to 4.8% alkali metal isethionate; and e) 2.7% to 13.5% by wt. water, wherein the sum of water, alkali metal isethionate and said water-soluble structurant is 10% to 60% of the final bar composition, wherein based on the total amount of water, alkali metal isethionate and said water-soluble structurant, water is present in an amount of 4 to 27%, alkali metal isethionate is present in an amount of less than 8% and said water-soluble structurant is present in an amount of 68 to 90%.

2. The bar composition according to claim 1 wherein said water soluble structurant is present at level of 13.6% to 45% by wt.

3. The bar composition according to claim 1, wherein said water-soluble structurant further comprises polyalkylene oxides having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 4% based on the weight of the composition.

4. The bar composition according to claim 1 wherein the polyalkylene oxides having a molecular weight in the range of 1,500 to 10,000 are polyalkylene glycol.

5. The bar composition according to claim 1 wherein the polyalkylene oxides having a molecular weight in the range of 1,500 to 10,000 are polyethylene glycol.

6. The bar composition according to claim 1 wherein the polyalkylene oxides having a molecular weight in the range of 50,000 to 500,000 are polyalkylene glycol.

7. The bar composition according to claim 1 wherein the polyalkylene oxides having a molecular weight in the range of 50,000 to 500,000 are polyethylene glycol.

8. The bar composition according to claim 1, wherein polyethylene oxide polypropylene oxide block copolymers comprise more than 40% by wt of polyethylene oxide.

9. A composition according to claim 1, wherein alkali metal isethionate is sodium isethionate.

10. The bar composition according to claim 1, wherein: water is present in an amount of 4 to 27%, alkali metal isethionate is present in an amount of less than 8% and water-soluble structurant is present in an amount of 68 to 90%, based on the weight of water, alkali metal isethionate and water soluble structurant taken together, wherein efflorescence is eliminated.

11. The bar composition according to claim 10, wherein the alkali metal isethionate is sodium isethionate.

12. The bar composition according to claim 10, wherein the polyalkylene oxides having a molecular weight in the range of 1,500 to 10,000 are polyalkylene glycol, preferably are polyethylene glycol.

13. The bar composition according to claim 10, wherein the polyalkylene oxides having a molecular weight in the range of 50,000 to 500,000 are polyalkylene glycol, preferably are polyethylene glycol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0032] Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word about. All amounts are by weight of the final composition, unless otherwise specified.

[0033] It should be noted that in specifying any range of concentration or amount, any particular upper concentration can be associated with any particular lower concentration or amount.

[0034] For the avoidance of doubt, the word comprising is intended to mean including but not necessarily consisting of or composed of. In other words, the listed steps or options need not be exhaustive.

[0035] The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found without multiple dependency or redundancy.

[0036] Final bar is prepared comprising: [0037] a) 10% to 60% by wt. total bar synthetic surfactant; [0038] b) 0% to 50%, preferably 5 to 45% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total surfactant (e.g., if using 20% synthetic, fatty acid soap is less than 12%) [0039] c) 6.8% to 54%, preferably 13.6% to 45% water-soluble structurants (e.g., polyalkylene glycol); [0040] d) 0% to 4.8%, preferably 0.1 to 3.6%, preferably 0.1% to 3.0% alkali metal isethionate; and [0041] e) 0.4% to 16.2%, preferably 2.7% to 13.5% by wt. water.

[0042] By water-soluble is meant that the structurant is dissolved to a substantially clear solution (except for small amounts of insoluble residue which may impart a translucent haziness to the otherwise clear solution) at 10% by wt. or greater of the structurant (e.g., starch) in water (i.e., at least 1 part in 10 should be soluble).

[0043] Synthetic surfactant means non-soap surfactant in this description. Suitable synthetic surfactants of (a) are: alkyl ether sulphates; alkylethoxylates; alkylethoxycarboxylates; alkyl glyceryl ether sulphonates; alpha olefin sulphonates; acyl taurides; methyl acyl taurates; N-acyl glutamates; acyl isethionates; anionic acyl sarcosinates; alkyl phosphates; methyl glucose esters; protein condensates; ethoxylated alkyl sulphates; alkyl polyglucosides; alkyl amine oxides; betaines; sultaines; alkyl sulphosuccinates, dialkyl sulphosuccinates, acyl lactylates and mixtures thereof. The above-mentioned detergents are preferably those based upon C.sub.8 to C.sub.24, more preferably those based upon C.sub.10 to C.sub.18, alkyl and acyl moieties.

[0044] For many embodiments of this invention, the amount of synthetic surfactant (a) may lie in the range from 10 to 50% wt. Further preferences are at least 20% and not more than 40%, preferably not more than 35% by wt. Again, fatty acid soap is used in lesser amounts.

[0045] The formulations can contain up to 50% or so fatty acid and fatty acid soap, subject to caveat above that fatty acid soap be used in amounts less than amount of synthetic surfactant.

[0046] The water-soluble structurant is required to melt in the temperature range from 40 C. to 100 C. so that it can be melted to form the bar composition but will be in a solid state at temperatures at which the bar will be used. Preferably, it has a melting point of at least 50 C. to 90 C.

[0047] Materials which are envisaged as the water-soluble structurant (c) are moderately high molecular weight polyalkylene oxides of appropriate melting point and in particular polyethylene glycols or mixtures thereof.

[0048] Polyalkalene glycols (especially polyethylene glycols or PEGs) which are used typically have a molecular weight in the range 1,500-10,000. However, in some embodiments of this invention it is preferred to include a fairly small quantity of polyethylene glycol with a molecular weight in the range from 50,000 to 500,000, especially molecular weights of around 100,000. Such polyethylene glycols have been found to improve the wear rate of the bars. It is believed that this is because their long polymer chains remain entangled even when the bar compositions is wetted during use.

[0049] If such high molecular weight polyethylene glycols (or any other water-soluble high molecular weight polyalkylene oxides are used, the quantity is preferably from 1% to 5%, more preferably from 1% or 1.5% to 4% or 4.5% by weight of the composition. These materials will generally be used jointly with a larger quantity of other water-soluble structurant (c) such as the above mentioned polyethylene glycol of molecular weight 1,500 to 10,000.

[0050] Some polyethylene oxide polypropylene oxide block copolymers melt at temperatures in the required range of 40 to 100 C. and may be used as part or all of the water-soluble structurant (c). Preferred here are block copolymers in which polyethylene oxide provides at least 40% by weight of the block copolymer. Such block copolymers may be used, in mixtures with polyethylene glycol or other water-soluble structurant.

[0051] Preferably, the total quantity of water-soluble structurant (c) is from 6.8% to 54%, preferably 13.5% to 45% of the composition.

[0052] Hence, preferably the invention relates to a bar composition comprising: [0053] a) 10% to 60% by wt. total bar synthetic (non-soap) surfactant; [0054] b) 0% to 50% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total synthetic surfactant; [0055] c) 6.8% to 54% water-soluble structurant of the group consisting of [0056] polyalkylene oxides having a MW of 1,500-10,000, [0057] polyethylene oxide polypropylene oxide block copolymers, [0058] mixtures thereof and [0059] wherein the water soluble structurant optionally further comprises polyalkylene oxide, having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5% based on the weight of the composition, preferably polyalkylene glycol, preferably polyethylene glycol; [0060] wherein the water-soluble structurant has a melting point of 40 to 100 C., 0.1% to 4.8% alkali metal isethionate; and [0061] d) 2.7% to 13.5% by wt. water, [0062] wherein the sum of water, alkali metal isethionate and said water-soluble structurant is 10% to 60% of the final bar composition, [0063] wherein based on the total amount of water, alkali metal isethionate and said water-soluble structurant, [0064] water is present in an amount of 4 to 27%, [0065] alkali metal isethionate is present in an amount of less than 8% and [0066] said water-soluble structurant is present in an amount of 68 to 90%.

[0067] The water-soluble structurant further comprises polyethylene glycol having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5%, preferably 1 to 4.5 wt %, more preferably 1.5 to 4 wt %, based on the weight of the composition. The amount is encompassed in the amount of water soluble structurant of 6.8 to 54%, as understood by the person skilled in the art. This would result in a preferred bar composition comprising: [0068] a) 10% to 60% by wt. total bar synthetic (non-soap) surfactant; [0069] b) 0% to 50% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total synthetic surfactant; [0070] c) 6.8% to 54% water-soluble structurant, of the group consisting of [0071] polyalkylene oxides having a MW of 1,500-10,000, [0072] polyethylene oxide polypropylene oxide block copolymers, [0073] mixtures thereof and [0074] wherein the water soluble structurant further comprises polyalkylene oxide, having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5% based on the weight of the composition, more preferably polyalkylene glycol, most preferably polyethylene glycol; [0075] wherein the water-soluble structurant has a melting point of 40 to 100 C., 0.1% to 4.8% alkali metal isethionate; and [0076] d) 2.7% to 13.5% by wt. water, [0077] wherein the sum of water, alkali metal isethionate and said water-soluble structurant is 10% to 60% of the final bar composition, [0078] wherein based on the total amount of water, alkali metal isethionate and said water-soluble structurant, [0079] water is present in an amount of 4 to 27%, [0080] alkali metal isethionate is present in an amount of less than 8% and [0081] said water-soluble structurant is present in an amount of 68 to 90%.

[0082] The polyalkylene oxides having a molecular weight in the range of 1,500 to 10,000 preferably are polyalkylene glycol, resulting in a preferred bar composition comprising to a bar composition comprising: [0083] a) 10% to 60% by wt. total bar synthetic (non-soap) surfactant; [0084] b) 0% to 50% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total synthetic surfactant; [0085] c) 6.8% to 54% water-soluble structurant of the group consisting of [0086] polyalkylene glycol having a MW of 1,500-10,000, [0087] polyethylene oxide polypropylene oxide block copolymers, [0088] mixtures thereof and [0089] wherein the water soluble structurant further comprises polyalkylene oxide, having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5% based on the weight of the composition, more preferably polyalkylene glycol, most preferably polyethylene glycol; [0090] wherein the water-soluble structurant has a melting point of 40 to 100 C., 0.1% to 4.8% alkali metal isethionate; and [0091] d) 2.7% to 13.5% by wt. water, [0092] wherein the sum of water, alkali metal isethionate and said water-soluble structurant is 10% to 60% of the final bar composition, [0093] wherein based on the total amount of water, alkali metal isethionate and said water-soluble structurant, [0094] water is present in an amount of 4 to 27%, [0095] alkali metal isethionate is present in an amount of less than 8% and [0096] said water-soluble structurant is present in an amount of 68 to 90%.

[0097] Polyalkylene oxides having a molecular weight in the range of 1,500 to 10,000 are preferably polyethylene glycol, resulting in a preferred bar composition comprising [0098] a) 10% to 60% by wt. total bar synthetic (non-soap) surfactant; [0099] b) 0% to 50% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total synthetic surfactant; [0100] c) 6.8% to 54% water-soluble structurant of the group consisting of [0101] polyethene glycol having a MW of 1,500-10,000, [0102] polyethylene oxide polypropylene oxide block copolymers, [0103] mixtures thereof and [0104] wherein the water soluble structurant further comprises polyalkylene oxide, having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5% based on the weight of the composition, more preferably polyalkylene glycol, most preferably polyethylene glycol; [0105] wherein the water-soluble structurant has a melting point of 40 to 100 C., 0.1% to 4.8% alkali metal isethionate; and [0106] d) 2.7% to 13.5% by wt. water, [0107] wherein the sum of water, alkali metal isethionate and said water-soluble structurant is 10% to 60% of the final bar composition, [0108] wherein based on the total amount of water, alkali metal isethionate and said water-soluble structurant, [0109] water is present in an amount of 4 to 27%, [0110] alkali metal isethionate is present in an amount of less than 8% and [0111] said water-soluble structurant is present in an amount of 68 to 90%.

[0112] Even more preferably, the invention relates to a bar composition comprising [0113] a) 10% to 60% by wt. total bar synthetic (non-soap) surfactant; [0114] b) 0% to 50% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total synthetic surfactant; [0115] c) 6.8% to 54% of the water-soluble structurants polyethene glycol having a MW of 1,500-10,000, and optionally further polyethylene glycol having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5% based on the weight of the composition; [0116] wherein the water-soluble structurant has a melting point of 40 to 100 C., 0.1% to 4.8% alkali metal isethionate; and [0117] d) 2.7% to 13.5% by wt. water, [0118] wherein the sum of water, alkali metal isethionate and said water-soluble structurant is 10% to 60% of the final bar composition, [0119] wherein based on the total amount of water, alkali metal isethionate and said water-soluble structurant, [0120] water is present in an amount of 4 to 27%, [0121] alkali metal isethionate is present in an amount of less than 8% and [0122] said water-soluble structurant is present in an amount of 68 to 90%.

[0123] Optionally, water insoluble structurants may be used, but are also required to have a melting point in the range 40 to 100 C., more preferably at least 50 C., notably 50 C. to 90 C. Suitable materials which are particularly envisaged are fatty acids, particularly those having a carbon chain of 12 to 24 carbon atoms. Examples are lauric, myristic, palmitic stearic, arachidonic and behenic acids and mixtures thereof. Sources of these fatty acids are coconut, topped coconut, palm, palm kernel, babassu and tallow fatty acids and partially or fully hardened fatty acids or distilled fatty acids. Other suitable water insoluble structurants include alkanols of 8 to 20 carbon atoms, particularly cetyl alcohol. These materials generally have a water solubility of less than 5 g/liter at 20 C.

[0124] The relative proportions of the water-soluble structurants and water insoluble structurants govern the rate at which the bar wears during use. The presence of the water insoluble structurant tends to delay dissolution of the bar when exposed to water during use and hence retard the rate of wear.

[0125] Water is present at levels of 0.4% to 16.2%, preferably 2.7 to 15.5% by wt. in the final bar.

[0126] WO95/12382 discloses a bar composition in Example 20 comprising

TABLE-US-00003 Ingredient Wt % Coco lactobionamide 40.00 Sodium cocoyl isethionate 15.00 Palmitic stearic acid 7.04 PEG8000 29.35 water 5.00 Misc. solids 3.08 Sodium isethonate 0.53

[0127] This composition is therefore not desired to be part of the claimed subject matter. Coco lactobionamide is not preferred as a surfactant and preferably absent from the composition.

[0128] In a second form, the invention comprises a method of determining region where efflorescence is eliminated from bars comprising: [0129] a) 10% to 60% by wt. total bar synthetic surfactant; [0130] b) 0% to 50%, preferably 5 to 45% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total surfactant (e.g., if using 20% synthetic, fatty acid soap is less than 12%) [0131] c) 6.8% to 54%, preferably 13.6% to 45% water-soluble structurants (e.g., polyethylene glycol); [0132] d) 0% to 4.8%, preferably 0.1 to 3.6%, preferably 0.1% to 3.0% alkali metal isethionate; and [0133] e) 0.4% to 16.2%, preferably 2.7% to 13.5% by wt. water
which method for calculating final range comprises multiplying the combined amount of water, alkali metal isethionate and polyalkylene glycol (where combined amount of the three in final bar is 10 to 60% of final bar) by the following amounts or ranges (also referred to as multiplication factor):

TABLE-US-00004 Alkali metal Isethionate (e.g., Water sodium isethionate) PAGs 4%-27% <8% 68%-90%

[0134] It is noted that a person skilled in the art will understand how to pick suitable combinations of water, alkali metal isethionate and PEG within range of 10 to 60% to make bars which fall within the claim limitation ranges when multiplying by the factors we have identified. Thus, for example, choosing a combination of 60%, the minimum and maximum amount of PEG must be 41% and 54% respectively, based on the multiplication factor.

[0135] In a third form, the invention comprises a method of eliminating efflorescence in bars comprising synthetic surfactants, polyalkylene glycol and alkali metal isethionate, which method comprises formulating bars having the following composition: [0136] a) 10% to 60% by wt. total bar synthetic surfactant; [0137] b) 0% to 50%, preferably 5 to 45% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total surfactant (e.g., if using 20% synthetic, fatty acid soap is less than 12%) [0138] c) 6.8% to 54%, preferably 13.6% to 45% water-soluble structurants (e.g., polyethylene glycol); [0139] d) 0% to 4.8%, preferably 0.1 to 3.6%, preferably 0.1% to 3.0% alkali metal isethionate; and [0140] e) 0.4% to 16.2%, preferably 2.7% to 13.5% by wt. water. [0141] wherein said method for calculating the final noted ranges comprises:
multiplying the combined amount of water, alkali metal isethionate and polyalkylene glycol (where combined amount of the three in final bar is 10 to 60% of final bar) by following amounts or ranges (also referred to as multiplication factor):

TABLE-US-00005 Alkali metal Water Isethionate PAGs 4%-27% <8% 68%-90%

[0142] Hence the invention further relates to the use of [0143] water in an amount of 4 to 27%, [0144] alkali metal isethionate in an amount of less than 8% and [0145] water-soluble structurant in an amount of 68 to 90%, based on the weight of water, alkali metal isethionate and water soluble structurant taken together,
for eliminating efflorescence in a bar composition comprising synthetic (non-soap) surfactant, polyalkylene oxide and alkali metal isethionate which method comprises formulating bar having the following composition: [0146] a) 10% to 60% by wt. total bar synthetic surfactant; [0147] b) 0% to 50% by wt. fatty acid and fatty acid soap wherein total fatty acid soap is less than 60% of the total synthetic surfactant. [0148] c) 6.8% to 54% water-soluble structurants of the group consisting of [0149] a. polyalkylene oxides having a MW of 1,500-10,000, [0150] b. polyethylene oxide polypropylene oxide block copolymers, [0151] c. mixtures thereof and [0152] wherein the water soluble structurant optionally further comprises polyalkylene oxides having a molecular weight in the range of 50,000 to 500,000 in an amount of 1 to 5% based on the weight of the composition; [0153] wherein the water-soluble structurant has a melting point of 40 to 100 C., [0154] d) 0.1% to 4.8% alkali metal isethionate; and [0155] e) 2.7% to 13.5% by wt. water.

[0156] In such use according of the invention the polyalkylene oxides having a molecular weight in the range of 1,500 to 10,000 are preferably polyalkylene glycol, and most preferably are polyethylene glycol.

[0157] Further, the polyalkylene oxides having a molecular weight in the range of 50,000 to 500,000 are preferably polyalkylene glycol, and most preferably are polyethylene glycol.

EXAMPLES

Examples 1-2 and Comparatives A-C

[0158] The following ternary systems were prepared:

TABLE-US-00006 PEG Water SI Visual observation Comparative A 68.61% 13.52% 17.88% Multi-phase efflorescent Comparative B 68.61% 22.44% 8.95% Multi-phase efflorescent Example 1 68.61% 26.91% 4.48% Stable and homogeneous Comparative C 81.88% 7.53% 10.59% Multi-phase efflorescent Example 2 89.81% 4.38% 5.81% Stable and homogeneous

[0159] These results were used to determine amounts of water, alkali metal isethionate and polyalkylene glycol which are critical to in turn determine amounts of each of the three in the final bar needed to eliminate efflorescence. The ranges for water (to use as multiplication factor) were determined to be from 4 to 27%; for alkali metal isethionate, range was determined to be less than 8% (can be as high as 8.5%), preferably less than 7%, more preferably less than 6%; and for alkylene glycol range was determined to be 68 to 90%.

Examples 3-4 and Comparatives D, E and F

[0160]

TABLE-US-00007 Ingredients Comparaitve D Comparative E Comparative F Example 3 Example 4 Sodium Cocoyl Isethionate 25.00% 25.00% 25.00% 30.00% 30.00% Fatty acid (s) 25.00% 26.00% 27.00% 27.00% 28.00% Fatty acid soap (s) 15.00% 15.00% 15.00% 12.00% 12.00% PEG (s) 20.00% 20.00% 20.00% 20.00% 20.00% Sodium Cocoyl Betaine 5.00% 3.00% 3.00% 3.00% 3.00% Water qs to 100% qs to 100% qs to 100% qs to 100% qs to 100% Sodium Isethionate 5.00% 5.00% 5.00% 2.30% 1.80% salt, colorant, preservative <2.0% <2.0% <2.0% <2.0% <2.0% Efflorescence Yes Yes Yes No No

[0161] The above formulations 3 and 4 comprise amounts of water, alkali metal isethionate and polyalkylene glycol formulation within required range of the invention and demonstrated no efflorescence. In particular, it will be seen that Examples 3 and 4 have 2.30% and 1.80%, respectively of sodium isethionate and do not demonstrate efflorescence. By contrast, Comparatives D, E and F have 5.0% sodium isethionate (above the 4.8% limit of our claimed composition) and these show efflorescence.