JP2566177C - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to fabric softening compositions, including fabrics, knits and the like, especially fabric softening compositions comprising one or more amines as active materials intended for use in the rinse cycle of the fabric washing process. About. It is an object of the present invention to develop a formulation of a fabric softening composition comprising one or more amines as active material. It is another object of the present invention to provide a fabric softening composition that is environmentally acceptable and exhibits good softening performance. One problem with fabric softener compositions containing amines is that they often cannot be as soft as conventional softeners containing quaternary ammonium softeners. It has been found that the softening ability of the amine containing fabric softener composition can be significantly improved by carefully adjusting the pH of the aqueous rinse solution each time the fabric is treated. The concentration of the amine material in the rinsing water is generally between 30 and 1000 ppm, preferably around 200 ppm. The pH of the aqueous rinse solution containing the amine softener material at 200 ppm concentration is the amine pK
It has been found that when less than or equal to a, improved flexibility is obtained. Accordingly, the present invention is a textile softening composition comprising one or more amine softening materials and one or more pH adjusting agents, wherein the pH of the aqueous liquid obtained by diluting the fabric softening composition to an amine material concentration of 200 ppm. Is a pH that is less than or equal to the pKa of the amine material. Amine Material The term amine soft material and the term used herein can use one or more amines of the following formula (I) that can be used to soften the fabric. Equation (i) (Wherein R ₁₅ , R ₁₆ and R ₁₇ are defined below). Suitable materials are described in European Patent Application No. 1993, incorporated herein by reference.
No. 82 (Procter and Gamble). When the amine is of the above formula (I), both R ₁₅ and R ₁₆ are C ₆ -C ₂₄ hydrocarbyl groups, most preferably C ₁₆ -C ₁₈ hydrocarbyl groups and R ₁₇ is C _1-3
It is a hydrocarbyl group, or R ₁₅ is a hydrocarbyl group of at least 22 carbon atoms and R ₁₆ and R ₁₇ are C _1-3 hydrocarbyl groups. Preferred amine materials are materials of formula (I) containing a long two hydrocarbyl groups (C ₆ ~C ₂₄₎ and short hydrocarbyl group (C ₁ ~C _{3) 1} pieces of. ARMMEEN M2HT (Akzo
It is preferred to use di-hardened tallow methylamine which is commercially available as). When using the latter material, the pH of the 200 ppm rinse is preferably 4.5 or less, more preferably less than 3.5. As used herein, the expression hydrocarbyl group refers to an alkyl or alkenyl group, optionally substituted or interrupted by a functional group such as -OH, -O-, -CONH, -COO-, and the like. pKa value The pKa value is a widely known parameter for the protonation of a substance. For certain amine materials, the pKa can be determined by considering the amine material protonation reaction amine + H ⁺ ... amine H ⁺ . The pKa of an amine is the pH value when the amount of unprotonated amine is equal to the amount of protonated amine. A possible way to determine the pKa of a substance is to determine the titration curve for a 1% dispersion of the substance with increasing amount of acid. That is, the pKa of a substance is the pH value at the midpoint of the steep portion of the titration curve. In Table I, the pKa values for the various amine soft materials are given. It is preferred to use amine materials having a pKa value of less than 6.5, preferably less than 5.5, particularly preferably between 5.2 and 4.0. If more than one amine material is present in the composition of the present invention, the pKa of the amine material
The value should be calculated as the weight average pKa value of the amine mixture. Liquid Product The composition of the present invention is a liquid containing an aqueous phase. The proportion of water in such an aqueous liquid is preferably 97 to 20% by weight of the composition, more preferably 95 to 70% by weight. The amine softener material concentration in the product of the invention, especially in the liquid product of the invention, is 1% by weight of the composition
Or more, more preferably 2% or more, and most preferably 3% or more. Preferably, the concentration of the amine softener material does not exceed 70% by weight of the composition, more preferably less than 30%, particularly preferably a composition comprising 3-20% by weight of the amine softener material. . A problem with the formulation of the liquid product according to the invention is that a low pH is required for the rinsing liquor, which generally requires a high concentration of pH modifier in the undiluted product. That is. These high concentrations of pH modifier destabilize the undiluted product by flocculation of the dispersed amine phase, causing phase separation. A second object of the present invention is to prevent the instability of the undiluted product while ensuring a suitable amount of the pH adjusting agent. It has been found that by holding the pH modifier in the undiluted product in a predominantly non-ionized form, the instability of the liquid fabric softener of the present invention can be prevented. In addition, the pH of the undiluted product must not be too low for consumer safety. Also pH
The regulatory material must have a sufficiently low pKa to provide the required pH at an amine concentration of 200 ppm. According to the present invention, the following 1.5 <pKa (pH adjuster) <pKa (amine), more preferably 2.0 <pKa (pH adjuster) <pKa (amine) -0.5, most preferably 2.5 <pKa (pH adjuster) <pKa It has been found that the above various requirements can be achieved in a well-balanced manner by selecting a pH regulator satisfying the condition of (amine) -1.0. When using a pH adjuster that exhibits more than one stage of deprotonation, the pKa (pH adjuster) used in the above equation is the lowest pKa value of the pH adjusting material. For example, citric acid has a pK
a It has values 3.1, 4.8 and 6.4, but in the above equation the value 3.1 is used as pKa (citric acid). When more than one pH modifier is used, the pKa value for the mixture of pH modifiers is pKa
The weight average pKa of the mixture of H-regulating materials. Other possible ways to increase the stability of the liquid products according to the invention include, for example, the use of pH modifiers which are relatively insoluble in the undiluted product but sufficiently soluble in the rinsing liquid. And the use of components that prevent flocculation of the dispersed phase. Examples of suitable deflocculated materials are disclosed in British Patent Application No. 8919669.5, filed August 31, 1989, filed by the same applicant as the present invention. pH adjuster The composition according to the invention comprises one or more pH adjusters. As mentioned above, the pH modifier must provide a specific pH to the rinse water. As soon as the pH required for the rinsing water has been determined according to the above teachings, it will be appropriate for a person skilled in the art to select the type and amount of pH adjusting material necessary to obtain the required pH. Generally, the pH modifier is an acid substance. The product according to the invention is a liquid product based on water, the pKa of the pH-adjusting material being higher than 1.5 but below the pKa of the amine. Again, once the pKa required for the pH adjusting agent has been determined according to the teachings above, it would be appropriate for a person skilled in the art to select a suitable acid and its amount. Typical concentrations of the pH-adjusting material in the liquid undiluted product are from 0.1 to 2.0 moles per liter, more preferably from 0.2 to 1.5 moles per liter, particularly preferably from 0 to 1 mole per liter.
.25 to 1.0 mole. The preferred pH adjusting material has a pKa of 2.5-3.5. Examples of these materials include p-
Aminobenzosulfonic acid, bromoacetic acid, chloroacetic acid, o-chloroacetic acid, α-chlorobutyric acid, citric acid, dihydroxybenzoic acid, dimethylmalic acid, dimethylmalonic acid, dinicotinic acid, fumaric acid, furancarboxylic acid, iodoacetic acid, lactic acid , Malic acid,
Malonic acid, methylmalonic acid, quinolinic acid, sulfanilic acid and tartaric acid. For environmental reasons tartaric acid, lactic acid, citric acid, malonic acid or mixtures thereof are preferred. Use of a pH-adjusting material with a pKa of 2.5 to 3.5 in combination with amines of the formula (I) containing two long hydrocarbyl groups (C ₆ -C ₂₄ ) and one short hydrocarbyl group (C ₁ -C ₃ ) Is preferred. It is particularly preferred to use these pH-adjusting materials in combination with the di-hardened tallow methylamine marketed under the trademark ARMEEN M2HT (Akzo). Additional Constituents The composition of the present invention may include one or more flexible materials selected from cationic, amphoteric and non-ionic flexible materials in addition to the amine and pH adjusting material. Suitable materials include, for example, EP 239 910 (P & G), U.S. Pat.No. 3,915,865 (STEPAN)
And materials as described in U.S. Pat. No. 4,137,180 (LEVER BROTHERS). The weight ratio of these added soft materials to the total amine soft material is preferably less than 3: 1, more preferably less than 1: 1 and particularly preferably less than 0.5: 1. Compositions, for example non-aqueous solvents such as alkanols of C ₁ -C ₄ and polyhydric alcohols, rewetting agents, electrolytic solution or longer (e.g., 25 to 40 EO) viscosity enhancing agents, such as alkoxylated fatty alcohols (E.g. calcium chloride), anti-gelling agents, perfumes, perfume carriers, fluorescent agents, pigments, hydrotropes, defoamers, anti-redeposition agents, enzymes, optical brighteners, opacifiers, stabilizers (e.g. guar gum and polyethylene Glycols), emulsifiers, anti-shrinkage agents, anti-wrinkle agents, textile crisping agents, stain inhibitors, stain release agents, bactericides, linear or branched silicones, fungicides, antioxidants, anticorrosives, preservatives ( For example, Proxel, ascorbic acid, Bronoopal® (commercially available in the form of 2-bromo-2-nitropropane-1,3-diol)), dyes, bleach and bleach precursors, draping agents, Antistatic agent and ironing aid It may contain one or more additional components selected from agents. It is preferred to add these additional components so that they are present at a concentration of 5% by weight or less of the composition. The composition according to the invention can be prepared in various ways. A preferred method of preparing a liquid product according to the present invention is to form a molten mixture of an amine material effectively in combination with another soft material, and add this premix to water with stirring to form a dispersion, , PH adjusting material and other additional components. The present invention can be further described by the following examples. Example I (Reference Example) Di-hardened tallow methylamine (Armeen M2HT) was dispersed in water at ambient temperature to give 200 pp of amine.
m. The pKa of the amine is 4.5. In tests 1 to 6, 1 l of a 200 ppm amine dispersion was adjusted to the pH described below with HCl. A piece of terry towel (40 g total weight) was rinsed in the amine dispersion for 5 minutes. The trim was dried in a line. The amount of amine deposited was determined by measuring the change in turbidity of the rinse. A high deposition percentage corresponds to better flexibility. The following results were obtained. These results indicate that good deposition (> 50%) is obtained when the pH of the rinse is equal to or less than the pKa of the amine. Good results are obtained especially when the pH of the rinsing liquid is at least 0.5 less than the pKa of the amine. Example II The performance and stability of various amines, including liquid textile softening compositions, were tested as follows. The laundry consisting of a 1.25 kg terry towel and a 1.25 kg cotton sheet fabric was washed in a Miele 756 Automatic at 40 ° C. with 100 g of Persil Automatic (UK). 90 ml of a rinse conditioner (corresponding to an amine concentration of about 200 ppm) containing 5% by weight Armeen M2HT, 1% by weight tallow 35EO and various amounts of pH adjusting material were added to the final rinse cycle. Table III shows the stability of the undiluted product, the pH of the undiluted product and the pH of the rinse. The lower pH value of the rinsing liquid corresponds to better softening properties. These results indicate that the use of low pKa acids, such as hydrochloric acid and oxalic acid, does not allow for the formulation of a stable product that will provide the required pH in the rinse. This indicates that the lower limit of the pKa of the pH regulator in the liquid product is 1.5. If orthophosphoric acid is used as a pH modifier, a stable product will be formulated, but unstable properties will occur at higher concentrations of acid, and if orthophosphoric acid is used, these higher acid concentrations will be used. Is necessary to lower the pH of the rinsing liquor to below the pKa of the amine. Thus, orthophosphoric acid is not preferred as a pH adjusting material for blending Armeen M2HT system. The use of malonic acid, citric acid or tartaric acid resulted in a stable composition and provided the preferred pH value even at relatively low concentrations of the acid material in the rinse. Similar results were obtained using lactic acid. Therefore, these materials are preferred for use in the Armeen M2HT system. The use of succinic acid results in a stable product, but these concentrated acid materials are often costly due to the need for concentrated acid materials to achieve the desired pH in the rinsing solution. Is not preferred for various reasons.

Claims (1)

Claims (1) A fabric softening composition comprising one or more amine softening materials, one or more pH adjusters and an aqueous base, wherein the fabric softening composition is diluted until the amine softening material has a concentration of 200 ppm. The pH of the resulting aqueous liquid is less than or equal to the pKa of the amine soft material as determined from the titration curve of the 1% dispersion of the amine soft material, and the one or more amine soft materials are Formula (I) Wherein (a) R ₁₅ and R ₁₆ are C ₆ -C ₂₄ hydrocarbyl groups, and R ₁₇ is C ₁
Or a hydrocarbyl group of -C _3, or (b) R ₁₅ is a hydrocarbyl group having at least 22 carbon atoms, R ₁₆ and R ₁₇ is a hydrocarbyl group of C ₁ -C _3] fabric softening of A fabric softening composition selected from amines, wherein the one or more pH adjusting agents satisfy the following formula: 1.5 <pKa (pH adjusting agent) <pKa (amine). (2) The fabric softening composition according to claim 1, wherein the pH of the diluted amine solution is at least 0.5 lower than the pKa of the amine. (3) The fabric softening composition according to claim 1 or 2, wherein the pH adjuster has a pKa of 2.5 to 3.5. (4) The fabric softening composition according to any one of claims 1 to 3, wherein the pH adjuster is selected from the group consisting of tartaric acid, lactic acid, citric acid, and malonic acid or a mixture thereof. (5) The fabric softening composition according to any one of claims 1 to 4, wherein the concentration of the pH adjusting agent is 0.25 to 1.0 mole per liter. (6) The fabric softening composition according to any one of claims 1 to 5, wherein the fabric softening amine of the formula (I) (b) comprises 1,2-dihardened tallow oxydimethylpropanamine. (7) The pH of the aqueous liquid obtained by diluting the fabric softening composition to a concentration of 200 ppm of the amine softening material, the pH of the amine softening material determined from the titration curve of a 1% dispersion of the amine softening material is determined. A process for producing a fabric softening composition which is less than or equal to the formula (I) Wherein (a) R ₁₅ and R ₁₆ are C ₆ -C ₂₄ hydrocarbyl groups, and R ₁₇ is C ₁
Or a hydrocarbyl group of -C _3, or (b) R ₁₅ is a hydrocarbyl group having at least 22 carbon atoms, R ₁₆ and R ₁₇ is a hydrocarbyl group of C ₁ -C _3] fabric softening of A process comprising combining one or more amine softeners selected from amines, one or more pH adjusters satisfying the formula: 1.5 <pKa (pH adjuster) <pKa (amine) and an aqueous base.