IE860831L - Fabric conditioner - Google Patents

Abstract

Aqueous dispersions of certain amines, with Bronstedt acids having a pKa of at least 6, are stable and are useful as rinse-added fabric softeners. [EP0197578A2]

Description

59115 This inuention relates to textile treatment compositions. More particularly it relates to textile treatment compositions suitable for use in the rinse cycle of a textile laundering operation to prouide fabric softening/static control benefits, the compositions being characterized by excellent softening, water dispersibility and storage properties after prolonged storage at both eleuated and sub-normal temperatures.

Textile treatment compositions suitable for prouiding fabric softening and static control benefits during laundering are well known in the art and haue found widespread commercial application. Conventionally, rinse-added fabric softening compositions contain, as the actiue component, substantially water-insoluble cationic materials hauing two long alkyl chains. Typical of such materials are di-hardened tallow dimethylaminoi"uurn chloride, and imida2o 1 in 1 usn compounds substituted with iujo tallow groups. Thes© materials are normally prepared in the form of a dispersion in water and it is generally not possible to prepare such aqueous dispersions ujith more than about 10 % of cationic softener without encountering severe product viscosity and storage-stability problems. Although more concentrated dispersions of softener materials can b® prepared as described in European Patent ftpplication IMo. 0 000 406 and British Patent Wo. I 601 360 by incorporating certain nonionic adjunct softening materials therein, such compositions tend to be relatively inefficient in terms of softening benefit/unit weight of active; moreover. product viscosity and stability problems become increasingly unmanageable in more concentrated aqueous dispersions and effectively limit the commercial range of applicability to softener active levels in the range from about 15% to about 20%.

U.S. Patent t 454 049. issued June 12. 1984 to HaeGilp et al discloses concentrated liquid fabric softeners comprising substantial amounts at least 10%. more typically about 30 - 40%, of water miscible organic solvent.

U.S. Patent 2 995 520, issued August 8, 1961 to Luvisi et al discloses the use of the acid salts of certain imidazoline derivatives for softening of fibrous materials such as cotton and paper. The treatment baths used for treating textiles contain from 0.001% to 1% of an acid ©alt of an imidazoline derivative. For shipment, it is said to be desirable to place the materials in a low molecular weight aliphatic alcohol to prevent freezing.

Oth&r patents, more reosmt than U.S. 2 995 520£, also disclose the use of an acid salt of an imidazoline derivative for the softening of fabrics,, such as FR-A-2 322 963,- Ht-A-2 391 312 describes compositions for industrial treatment of textiles wherein imidazoline derivatives are used as sole softening agents, together with em organic fluidizer. 4 However,, according to the state of the art, quaternary ammonium salts are, in the context of fabric softening, preferred over acid salts of, e.g., acyclic tertiary amines or cyclic amines.

It is therefore an object of the present invention to provide liquid fabric softening compositions that can be formulated as both diluted and concentrated aqueous dispersions without the need of significant amounts of organic solvents. The compositions of the present invention have excellent stability at both elevated and sub-normal temperatures, even under prolonged storage conditions. These compositions further provide excellent softening, anti-static and fabric rewettability characteristics across a broad range of fabric types.

The present invention provides a stable aqueous dispersion comprising: (a) from 1% to 40% by weight of an amine selected from the group consisting of the di(higher alkyl) cyclic amines of formula I herein; and mixtures thereof; (k) a compound selected from the group of conventional quaternary ammonium salt softening agents having two higher alkyl groups, each comprising from 8 to 30 carboru atoms, the weight ratio of (a) to (b) being in the range of from 3sl to Is10? and (c) from 1% to 50% by weight of the amine of a dispersing aid selected frcm the group of Bronstedt acids having a pKa value of not greater than 6? provided that the pH of the dispersion is not greater than 5„ The compositions of the present invention are based upon the discovery that stable aqueous dispersion can be formulated with certain cyclic amines, even at high amine concentration, and a conventional di(higher alkyl) quaternary ammonium salt, without the use of substantial amounts of organic solvent. a) The amine The amines used in the compositions of the present invention are selected from the group consisting of compounds of the formula I.

Formula I .'CH2>n \ Q X N X - R. wherein n is 2 or 3, preferably 2; R^ and are, independently, a C.-C-- alkyl or alkenyl, preferably O ju alkyl, more preferably C1E.-C1cl alkyl, or 1 1 <£<& lb It) mixtures of such alkyl radicals. Examples of such mixtures are the alkyl radicals obtained from coconut oil, "soft" (non-hardened) talloui, and hardened talloui. Q is CH, CH^, JV)L, or N, preferably N.

X is - R4 - T - C - I 0 uiherein T is WR&, R,. being H or Cj-C^ alkyl, preferably H, and R^ is a divalent Cj-Cj alkylene group or (C_H„0) , therein m is an number of from 1 & 4 HI to 8; or X is R^.

The compositions of the present invention comprise from 1% to 40% by weight of the amine, preferably from 2% to 3S%, and more preferably from 2% to 20%.

Detergent carryover, as may take place in a laundry process, particularly under conditions as prevail in U.S. mashing machines, tends to negatively affect the softening performance of rinse added softeners. It has been found that the amines of formula I are less sensitive to 6 detergent carryover than, e.g. ditallomdimethylammonium chloride. b) Quaternary ammonium salt As a second component, the dispersions herein contain a conventional di(higher alkyl) quaternary ammonium softening agent. By "higher alkyl" as used in the context of the quaternary ammonium salts herein is meant alkyl groups having from 8 to 30 carbon atoms, preferably from 11 to 22 carbon atoms. Examples of such conventional quaternary ammonium salts include (i) acyclic quaternary ammonium salts having the formula : 4 - R. a© wherein R^ is an acyclic aliphatic Ci5-C22 hydrocarbon group. R3 is a Cj-C^ saturated alkyl or hydroxyalkyl group, R^ is selected from R^ and R3, and A is an anion. (ii) diamido quaternary ammonium salts having the formula O R O II \ II Rj- C - IMH - R2 - N - R - NH - C - Rj I > R„ t e*9 ( wherein Rj is an acyclic aliphatic C15-C2i hydrocarbon group, is a divalent alkylene group having 1 to 3 carbon atoms, R^ and Rg are saturated alkyl or hydroxyalkyl groups, and A~ is an anion: (iii) diamido alkoxylated quaternary ammonium salts having the formula: Examples of Component (i) are the well-known dialkyldimethylammoniums salts such as ditallouidimethylammonium chloride, ditallowdimethylammonium methylsulfate, di(hydrodrogenated tallow) dimethylammonium chloride, distearyldimethylammonium chloride, dibehenyldimethylammonium chloride.

Examples of Component (ii) are methylbis(tallowamidoethyl) (2-hydroxyethyl) ammonium methylsulfate and methylbis(hydrogenated tallowamidoethyl) (2-hydroxyethyl) ammonium methylsulfate wherein R^ is an acyclic aliphatic C,r-C,„ hydrocarbon group, R_ is an lb 1 / I. ethwlene group, Rr is a methvl group, R_ is a " o hydroxyalkyl group and A is a methylsulfate anion; these materials are available from Sherex Chemical Company under the trade names Varisoft (R) 222 and Uarisoft (R) 110, respectively.

Examples of (iu) are l-methyl-l-tallowamido-ethyl~2-tallowimida2olinium methylsulfate and l-methyl-l-(hydrogenated tallowamidoethyl)-methylsulfate.

The quaternary ammonium salt (b) preferably comprises from 1% to 20%, more preferably 2% to 20% by weight of the composition herein.

The weight ratio amine (a): quaternary ammonium salt (b) is in the range from 3:1 to 1:10, preferably from 3:1 to 1:3.

The di(higher alkyl)imidazolinium compounds are preferred for use herein, in particular the l-(lower alkyl)-l-(higher alkyl)amidoethyl-2-(higher alkyl) imidazolinium compounds, wherein "lower alkyl" signifies alkyl hawing from 1 to 4 carbon atoms, and "higher alkyl" signifies alkyl hauing from 11 to 22 carbon atoms. c) Bronstedt acid The dispersion further comprises Bronstedt acids hauing a pKa ualue of 6 or less.

The amount of acid should be such that the pH of the dispersion, after mixing, is not greater than 5, preferably not greater than 4, and most preferably in the range of from 2.5 - 4. The amount of acid is from 1% to 50% by uieight of the amine, preferably from 2% to 30%, most preferably from 3 to 15%.

Examples of suitable acids include the inorganic mineral acids, carboxylic acids, in particular the low molecular weight (C^-C^) carboxylic acids, aromatic carboxylic acids, like benzoic acid, and alkylsulfonic acids.

Suitable ionorganic acids include HCl, HBr, H^SO^, HW03 and HgPO^. Suitable organic acids include benzoic acid, formic, acetic, methylsulfonic and ethylsulfonic acid. Preferred acids are phosphoric, formic and methylsulfonic acid. d) Organic solvent The compositions of the present invention can be formulated without the use of any organic solvent.

Howeuer, the presence of organic solvents (for example, low molecular weight, water miscible aliphatic alcohols,) does not harm the storage stability, the uiscositv, or the softening performance of the compositions of this invention.

Typically, the amine will be obtained from a supplier of bulk chemicals in solid form of as a solution in an organic solvent, e.g. isopropanol. There is no need, whatsoever, to remove such a solvent in making the compositions of this invention. Indeed, additional solvent may be added, if this is deemed desirable.

However, compared to water, organic solvents are expensive, and difficult to handle because of their flammability and, sometimes, toxicity. It is therefore desirable to formulate the present compositions with low levels of organic solvent, i.e., less than 10%, preferably less than 2%. e) Optional silicone Component The compositions herein can optionally contain an aqueous emulsion of a predominantly linear polydialkyl or alkyl, aryl siloxane in which the alkyl groups can have from one to five carbon atoms and may be wholly or partially fluorinated. Suitable silicones are polydimethyl 18 siloxanes hawing a viscosity at 25°C in the range from 100 to 100,000 centistokes (mm2/s), preferably in the range from 300 to 6,000 centistokes (mm2/s)- It has been found that the ionic charge characteristics of the silicone as used in the combination are important in detenaining both the extent of deposition and the evenness of distribution of the silicone and hence the properties of a fabric treated therewith.

Silicones having cationic character show an enhanced tendency to deposit. Silicones found to be of value in providing fabric feel benefits have a predominantly linear character and are preferably polydialkyl siloxanes in which the alkyl group is most commonly methyl. Such silicone polymers are frequently manufactured commercially by emulsion polymerisation using a strong acid or strong alkali catalyst in the presence of a nonionic or mixed nonionic-anionic emulsifier system.

In the present invention, the optional silicone component embraces a silicone of cationic character which is defined as being one of (a) a predominantly linear di C|_C5 alkyl or C^-C^ alkyl, aryl siloxane, prepared by emulsion polymerisation using a cationic surfactant as emulsifier; (b) an alpha-omega-di quaternised di cj-c5 alkyl or Cj-Cj. alkyl, aryl siloxane polymer or (c) an amino-functional di alkyl or alkyl aryl siloxane polymer in which the amino group may be substituted and may be quaternised and In which the degree of substitution (d.s.) lies in the range 0.001 to 0.1, preferably 01-0.075; provided that the uiscosity at 25°C of the silicone is from 100 to 100,000 cs (mm2/s)„ The weight ratio of the siloxane to the amine component of the composition herein typically ranges from 5:1 to 1:100, preferably from 2:1 to 1:10.

The silicone component suitable for use herein are more fully disclosed in British Patent Wo. 1.549.180. f) Optional nonionics The compositions optionally contain nonionics as have been disclosed for use in softener compositions. Such nonionics and their usage levels, have been disclosed in U.S. Patent 4.454.049, issued June 12,1984 to Mac Gilp et al.

Specific examples of nonionics suitable for the compositions herein include glycerol esters (e.g., glycerol monostearate), fatty alcohols (e.g.,stearyl alcohol), and alkoxylated fatty alcohols. The nonionics, if used, are typically used at a leuel in the range of from 0.5 - 10% by ueight of the composition. g) Other Optional Ingredients In order to further improve the stability of the compositions herein, and further adjust their viscosities, these compositions can contain relatively small amounts of electrolyte. A highly preferred electrolyte is CaCl2< It has been found that the Brookfield viscosities of highly concentrated dispersions can be reduced to less than 100 cps (100 mPas), using relatively small amounts of CaCl^ (e«,g„,,600 ppm).

The compositions herein can optionally contain other ingredients knoutn to be suitable for use in textile softeners. Such adjuvants include perfumes, preservatives, germicides, colorants, dyes, fungicides, stabilizers. brighteners and opacifiers. These adjuuents, if used, are normally added at their conventional leuels.

Howeuer, in the case of composition ingredients utilized for a fabric treatment effect, e.g., perfumes, these materials can be added at higher than normal leuels, corresponding to the degree of concentration of the product.

EXAMPLES I-IU The following compositions are prepared : EX. I EX.II EX.III EX. IU DTI15 20% 10% 8% DTDMAC2) - 10% 12% 15% PDMS3) - - 1% Acid 0.2%4) - - 0.4%5) CaCU(ppm) 600 800 900 1200 GMS - 1% - Stearyl Ale. - - 1% - Amine 7) 10% 8% 5% 10% perfume 0.9% 0.9% 0.9% 0.7% water balance balance balance balance 1) ditallow irnidazolinium (l-methyl-l-tallow-amido-ethyl-2-imidazolinium chloride) 2) ditallowdimethylammonium chloride 3) polydimethyl siloxane, uiscosity 500 centistokes (mm /s) 4) formic acid ) methylsulfonic acid 6) glycerolmonostearate 7) l-tallowamidoethyl-2-tallowimidazoline n i J Some hydrolysis of the ditallow irnidazolinium component is observed to take place during processing. This is not found to markedly affect the softening performance of the compositions.

EXAMPLES U - UIII The following examples are prepared, each having pH values in the range 2.5 to 5.

Ingredient-5* Ex U Ex VI Ex VII Ex VIII DTDflAC1 2 , ,33 7 .0 1 .26 3 . 78 PDMS2 1 . , 33 .0 0.333 1.0 Amine3 4. .33 13 2.34 7.02 HCl 0, ,268 0 . 805 0. 145 0.43 5 CaCl „ 0. 005 0 . 17 - 0. 1 A Emulsifier 0. 133 0 . 5 0 033 0. 1 Perfume/Dye 0. ,252 0 .753 0. 251 0.752 Water to 100% to 100% to 100% to 100% ** All ingredients listed at percent by weight of compositions 1. DTDHAC - As in Examples II, III and IV. 2. PDMS - Polydimethylsiloxane, viscosity 5000 cs (mm2/s)„ 3. Amine - l-(2-C1^-Clg-Amidoethyl)-2-C]l3-C17-alkyl - 4j,5 dihydro —imidazoline; CAS number 72623-82-6. 4. Emulsifier - As "Sapogenat T 100" (Trade Flark) for triisobutylphenol decaglycolether, Hoechst. 14 SIMMS X„ A stable aqueous dispersion comprising : (a) from 1% to 40% by weight of an amine selected from the group consisting of the cyclic amines of the formula : CK M - I - R? ' Ri wherein n is 2 or 3P R-, and M3 ar®f independently e a Cg-C30 alkyl or alkanyl radical , Q is CEe CH?, NH or N. % is - R- - T - C - * it Q herein T is NE^, Rg being H or C^-C^ alJfyl,, and H4 is a divalent Cj_-C3 alkylen® group or (CgH^Q)^, therein m mnotoer of from 1 to 8? or X is.:- „ and mixtures thereof; (h) a cowpmmS selected from the group ©f conventional quaternary ammonium salt softening agents having two alJofl groups each comprising from 8 to 30 carbon atoms, the weight ratio of (a) to (to) teeing in the range of from 3 si to 1:10'; and (a) from 1% to 50% by weight of the amine of a dispersing aid selected from the group of Bronstedt acids having a pKs, value of not greater than Si provided, that the pi of the dispersion is not greater than 5. 2. A dispersion according to claim 1 wherein the weight ratio (a):(b) is in the rang© from 3:1 to 1^3. 1 3. A dispersion according to any of the preceding ^

Claims (1)

1. claims which comprises from 2% to 35% by weight of the amine. 3. 15 4. A dispersion according to any of the preceding claims wherein the amine is a alkyl) affiiclosthyl-a-(C^^.^22 alkyl) imidazoline. 5. A dispersion according to any of the preceding claims which further comprises an emulsion of predominantly linear di(Cj_-C5) alkyl or C^-Cg alkylaryl siloxane in "«?hich the alkyl groups may be partially or wholly fluoridated and which may be substituted with cationic nitrogen groups, the siloxane having a viscosity at 25"C of at least 100 centistokes (md;'/s) and up to 100000 centistokes (sma^/s) .* the weight ratio of the siloxane content of the emulsion to the amine component being in the range of from S:1 to Is 100, preferably 2si to Is 10„ 6. A A dispersion according to elaiaa 6 wherein the siloxane is a polydisaethyl siloxane. 7. ™ A dispersion according to any of the preceding claiias yhich further comprises from 0.5% to 10% by weight of a nonionic, preferably & glycerol ester, a fatty alcohol„ or 8. A dispersion according to claim 1, substantially as hereinbefore described and exemplified. F. H. KELLY & CO., AGENTS FOR THE APPLICANTS.