DE69415546T2 - CONDITIONING DETERGENT - Google Patents

Description

CONDITIONING DISHWASHER

This invention relates to conditioning rinse agents, containing a softening or antistatic component.

Historically, fabric conditioning was accomplished either during the rinse stage of a fabric washing and rinsing process or during tumble drying of the fabric. In almost all cases, rinse conditioning is accomplished by adding a liquid dispersion of a rinse conditioning agent to the rinse liquid. The liquid dispersion was usually dispensed and made available to consumers as a ready-to-use aqueous dispersion. More recently, environmental concerns and consumer benefits have led to the sale of concentrated aqueous dispersions which are either used in smaller amounts or mixed with water to form a pre-dilution prior to use.

In EP 234 082 it was proposed to supply conditioning detergent as a solid block. This approach requires the use of a special constraint for the block and may also require redesigning the washing machine to enable the block to be dissolved and distributed by an atomization system.

Various proposals have been made for delivering fabric softeners in granular or powdered form. EP 111 074 is typical and uses a silica to carry the softener. A disadvantage of using a carrier such as silica is that it makes the product difficult to swell and serves no function other than to make the powder compatible with other ingredients that may be contained in a washing powder.

WO 92/18593 describes a granular fabric softening composition containing a nonionic fabric softener and a single long alkyl chain cationic material. The specification teaches that effective cationic softening compounds have poor dispersion properties when used in granular form.

It is well known to those skilled in the art that poor dispersion of a fabric softening active can result in poor softening of fabrics and unsightly deposition of clumps of the fabric softening active on the fabric.

The problem of poor dispersion of granular compositions is overcome by EP 569 184. This application describes the use of the granular composition to form a pre-dilution which is then added to the detergent dispenser drawer of the washing machine.

EP 568 297 discloses a granular fabric conditioning agent containing a nonionic dispersing aid and a water-insoluble cationic active agent of the following formula:

wherein each R1 group is independently selected from C1-4 alkyl, hydroxyalkyl or C2-4 alkenyl groups; and wherein each R2 group is independently selected from C2-27 alkyl or alkenyl groups and n is an integer having a value of 0 to 5.

Another problem with some cationic fabric conditioning actives is that of hydrolytic stability. EP 0 239 910 (Procter and Gamble) describes this problem and attempts to solve it by limiting the pH range of the aqueous formulations.

The present invention alleviates the problems of both hydrolytic stability and dispersion of a granular fabric conditioning agent.

According to the present invention there is provided a powdered conditioning rinse comprising:

a) at least 40% by weight of a water-insoluble cationically active compound of the formula:

in which R¹ is a C₁₋₄-alkyl group, R² and R³ are the same or different C₁₋₄₂-alkyl or alkenyl groups, X⁻ is a plasticizer-compatible anion and T

or

or

is and

II ü II

b) a wetting agent,

c) 1 to 20 percent by weight of a fatty acid.

It is preferred if the water-insoluble cationically active compound has the formula:

in which R¹ is a C₁₋₄-alkyl group, R² and R³ are the same or different C₁₂₋₂₂-alkyl or alkenyl groups, X⁻ is a plasticizer-compatible anion.

It is further preferred if the water-insoluble cationically active compound is N,N-di-(tallowoyl-oxy-ethyl)-N,N-dimethylammonium chloride.

It is advantageous for good resolution and dispersion, when the temperature of the rinsing water is above 10ºC, preferably above 20ºC. However, a suitable degree of softening is achieved below 10ºC.

Preferably, the cationically active compound contains more than 40% by weight of the powder and less than 95% by weight of the powder, more preferably the content of the cationically active compound is greater than 60% by weight of the powder.

The powder may also contain a coactive agent up to 20%. Preferred coactive agents are fatty acids.

It is preferred to enhance softening if from about 1% to about 15% by weight of fatty acid is present in the composition. Ideally, the ratio of cationic active compound: fatty acid is greater than 6:1. More preferably, the ratio of cationic active compound: fatty acid is 12:1, most preferably 20:1. The coactive fatty acid may include hydrogenated tallow fatty acid.

The composition of the invention also contains a humidification aid. In the context of the present invention, a humectant can be defined as any material which promotes the penetration of water into the softening material and thus aids in the rinsing and dispersion of the material. In some cases, the humectant can further enhance softening. Preferred humectants are non-ionic materials such as sugar alcohols, alcohol ethoxylates, (poly)ethylene glycols and mixtures thereof. Of particular use in the present invention are long chain alcohol ethoxylates, preferably alcohol ethoxylates with a chain length between 9 to 20, with alcohol ethoxylates with more than 5 moles of ethylene oxide such as Dobanol 91-6EO (trademark of Shell) and Genapol C-100 (trademark of Hoechst) being particularly preferred due to superior biodegradability.

Preferably, the content of humectant is between 1% and 20% by weight.

Advantageously, the powder can also be a flow aid and other ingredients commonly found in conditioning rinses such as perfume, antifoaming agent, preservative, colorant and dispersing aids such as low molecular weight cationic compounds.

For environmental reasons, it is advantageous if the quaternary ammonium material is biodegradable:

The invention is particularly useful when applied directly to the rinsing liquid.

The invention will now be described with reference to the following non-limiting examples:

EXAMPLES

Examples were prepared according to the formulation in Table I. These examples are not lengthy explanations of the invention. Table I

The compositions were prepared by shearing the components together.

1) DEEDMAC is N,N-(ditallowoyl-(oxyethyl)-N,N-dimethylammonium chloride from Hoechst.

* Trademark

The dispersibility of the examples in water was assessed by weighing 5 g of conditioning powder into a glass jar and adding 95 g of demineralized water (at 20ºC or 7ºC). The jar was tightly capped and shaken for 2 seconds. The dispersion was filtered through the pre-weighed Polymon 43T (trade mark) sieve (150 µm). The sieve was then oven dried and the percent residue calculated.

The dispersibility results are explained in Table II. Table II

The results show that Example 1 has superior dispersibility over Examples A and B when the water temperature is 20ºC.

The softening properties on the fabric of Examples A, B and 1 were evaluated by adding three 19 x 19 cm squares of standard 8 terry cloth (40 g) to cold US water. 1 ml of sodium alkylbenzene sulfonate solution was added and the Tissues were agitated (80 rpm) for one minute. Tissues were removed from the jar and product was added to the solution at the appropriate time. Tissues were added to the jar and agitated for 5 minutes. Tissues were removed, spun dry and line dried overnight.

Softening of the fabrics was determined by an expert panel of 4 people using a paired interlaboratory comparison test protocol. Each panel member selected four sets of test fabrics. Each set of test fabrics contained one fabric from each test system under evaluation. Panel members were asked to pick up the softer fabric from each pair during evaluation. A "no difference" statement was not allowed. Softness ratings were calculated using an analysis of variance procedure. Higher values indicate better softening.

The softening ratings of Examples A, B and 1 are explained below.

Example softening rating (7ºC)

1 88

A42

B42

It is therefore shown that Example 1 softens better than Examples A and B.

Claims (6)

1. A powdered conditioning rinse, containing: a) at least 40% by weight of a water-insoluble cationically active compound of the formula: in which R¹ is a C₁₋₄-alkyl group, R² and R³ are the same or different C₁₋₄₂-alkyl or alkenyl groups, X⁻ is a plasticizer-compatible anion and T or or is; b) a wetting agent, c) 1 to 20 percent by weight of a fatty acid. 2. A powdered conditioning rinse according to claim 1, wherein the water-insoluble cationic active compound has the formula: in which R¹ is a C₁₋₄-alkyl group, R² and R³ are the same or different C₁₂₋₂₂-alkyl or -alkenyl groups and X⁻ is a plasticizer-compatible anion. 3. A powdered conditioning rinse according to claim 2, in which the water-insoluble cationically active compound is N,N-di(tallowoyl-oxy-ethyl)-N,N-dimethylammonium chloride . 4. A powdered conditioning rinse agent according to any one of the preceding claims, in which the wetting agent is a non-ionic active compound. 5. A powdered conditioning rinse according to any of the preceding claims, wherein the content of surfactant is between 1% and 20% by weight. 6. A powdered conditioning rinse according to any of the preceding claims, which contains between 1% and 15% by weight of fatty acid.