DE69613004T2 - LIQUID DETERGENT COMPOSITION CONTAINING DISPERSED HYDROPHILIC SILICA. - Google Patents

Description

Field of the invention

The present invention relates to low or no water-containing liquid detergent compositions comprising solid particles and a process for preparing such particles and such liquids.

Background and state of the art

Liquid detergent compositions with low water contents are known in the art and have been described in a number of patent publications, for example in US-A-4 316 812, US-A-4 874 537 and EP-A-0 484 095, and provide a way to concentrate liquid detergents without sacrificing washing performance.

Liquid detergent compositions with low or no water content may comprise a liquid phase and a dispersion of solid detergent components and adjuvants depending on the intended use, mainly surfactants and builders.

The liquid phase frequently comprises a non-ionic surfactant as the main component, which, in addition to acting as a carrier liquid for the detergent components, usually and preferably also has detergent-active properties, whereby it preferably acts completely or partially as a surfactant component. The liquid phase may comprise a non-ionic surfactant and/or surfactant mixtures, such as mixtures of C₁₃-C₁₅- alcohols having an average of 3 ethoxy groups and C₁₃-C₁₅ alcohols having an average of 7 ethoxy groups and liquid phases as described in GB-A-1 462 134, WO-A-91/12313, WO-A-91/14765 and EP-A-0 510 762.

The solid phase may comprise, for example, builders, bleaches, abrasives, dispersants, enzymes, solid surfactant material and/or minor ingredients such as fluorescers. It has been found very difficult to stabilize suspended solid particles in liquid compositions and various solutions have been proposed in the prior art.

Fluids with low or no water content comprising dispersed solid particles of the prior art generally contain high levels of solid material. Levels of 25% by weight or higher are generally used to achieve stable dispersions of the solid particles in the liquid phase or to achieve a desired performance. However, high levels of solid particles can result in fluids with higher viscosity and/or poor dispersibility.

Various prior art documents have suggested the use of silica material in liquid detergent compositions. GB-A-1 205 711 discloses non-aqueous liquids comprising hydrophilic silica and solid dispersed silica. We have found that the prior art liquids can exhibit settling, sedimentation, clear layer separation and/or poor dispersibility.

Enzymatic liquid compositions with little or no water content can be prepared by adding enzyme slurries to the liquid. These slurries require special processing to produce and are consequently more expensive. They are non-aqueous and viscous, which means they are more difficult to handle. Furthermore, we have found that preparations with low water contents made with enzyme slurries suffer from instability.

EP-A-0 666 301 describes an antifoam composition comprising hydrophilic silica, silicone, detergent and water.

Surprisingly, we have now found that one or more of these disadvantages can be overcome by liquids with little or no water content.

We have found that low solids can be stably incorporated into liquids with little or no water liquors when a hydrophilic silica is included.

Furthermore, we have found that the inclusion of silicone material improves the properties of liquids with low or no water content that contain solid particles.

Furthermore, we have found that fluorescers and/or antiredeposition agents can be incorporated into liquids with low or no water content using hydrophilic silica.

We have further found that fluids containing less than 12% by weight of water and enzymes can be prepared with good properties when the fluid comprises silicone material and hydrophilic silica.

We have further found that enzyme-containing liquids can be prepared by mixing the enzyme with a liquid composition containing silicon dioxide, less than 12% by weight Water and also silicone and surfactant material.

Description of the invention

Accordingly, the present invention relates to a liquid detergent composition comprising water, surfactant material, silicone material and 0.05 to 20% by weight of a dispersed solid phase comprising hydrophilic silica material and enzyme material, according to claim 1.

Preferably, the liquid detergent composition of the present invention further comprises fluorescent agents in an amount of 0.01 to 10%, preferably 0.02 to 2% by weight and/or antiredeposition agents in an amount of 0.1 to 5% by weight of the composition.

The present invention is further directed to a process for preparing a liquid detergent composition of the invention according to claim 6.

Description of the invention in detail

WO-A-94/29427 discloses liquids containing highly viscous silicone droplets which may contain silica particles and wherein the compositions further comprise hydrophobic silica particles.

WO-A-94/23009 discloses liquids containing hydrophobic silicon dioxide to which silicone oil can be added.

CA-A-2 066 008 discloses liquids containing droplets of silicone oil, where the droplets may comprise silicon dioxide, for example DB100 and Thompson-Hayward AF-IND-100.

EP-A-573 699 discloses silica particles (in which nonionic surfactant is absorbed) dispersed in silicone oil to produce antifoam particles. These Particles may be entrapped in liquids. The surfactant within the silica prevents the silicone/silica droplets from coagulating during storage.

EP-A-583 512 discloses the use of particles of silicon dioxide with silicone to protect sensitive components, such as enzymes, in liquids.

GB-A-2 186 884 discloses particles (or droplets) of hydrophobic silica and silicone for use as enzyme stabilizers.

GB-A-1 205 711 discloses liquids containing hydrophilic silicon dioxide and enzymes.

We have found that hydrophilic silica enables the formulation of fluids containing less than 12% by weight of water and small amounts of dispersed solid phase. The fluids are stable and of low viscosity with little or no settling and little or no clear layer separation, while exhibiting good dispersibility.

We have further found that silicone inclusion in liquids containing hydrophilic silica and little or no water content enables stable suspension of solid particles, while the resulting liquid has low viscosity, little or no settling, little or no clear layer separation and good dispersibility.

We have further found that fluids containing fluorescer and/or antiredeposition agent can be stably formulated with hydrophilic silica and little or no water. Preferably no electrolyte is present and preferably the fluid contains some water.

Hydrophilic silica material

The present invention requires the presence of hydrophilic silica, preferably in dispersed form in the continuous phase of the liquid, forming a network capable of dispersing solid particles. Surprisingly, we have found that the low solids, silicone, fluorescer and/or antiredeposition agent liquids of the invention do not have the disadvantageous properties of prior art liquids containing hydrophilic silica.

Hydrophilic silica material may be selected from amorphous silica, precipitated, fumed silica, gelled silica and mixtures thereof. An example of such a silica material is Aerosil 200TM. Mixtures of hydrophilic and hydrophobic silica (e.g. Sypernat) may also be used, for example on a 50:50 basis.

Preferably, the silicon dioxide content is higher than 0.5%, more preferably higher than 1.0%, particularly preferably higher than 2% by weight of the composition. Preferably, the content is less than 8%, more preferably less than 6%, particularly preferably less than 4% by weight of the composition.

Silicone material

WO-A-93/24603, WO-A-94/01525 and WO-A-94/01524 disclose non-aqueous fluids containing DB100, which is a commercially available silicone polymer material. EP-A-515 418 and EP-A-515 435 disclose the use of silicone material in non-aqueous fluids.

Preferably, the silicone material is selected from polydialkylsiloxanes, where the alkyl may be, for example, C1-C6 and preferably represents a methyl group. Polydialkylsiloxanes may terminate in blocking moieties, for example, a trimethylsilyl moiety. An example is DB100TM from Dow. Silicone may be added to the composition in the form of a mixture with silica material.

Preferably, the silicone material is present in proportions of 0.01 to 1%, more preferably 0.05 to 0.5% by weight of the composition.

We have found that the physical properties of the fluids of the invention can be improved by incorporating the silicone material.

Water

Liquids according to the invention cannot contain water. However, the water content of liquid detergent products of the invention is less than 12%, more preferably less than 10% and preferably more than 2%, 0%, more preferably more than 5% by weight of the composition. This is particularly surprising since the skilled person would not be inclined to add water to liquids containing little water. Instead, he would try to keep all components and devices as dry as possible.

Enzymes

As indicated above, we have found that the use of aqueous enzyme preparations results in stable enzyme liquids, for example, compared to the use of enzyme slurries which may, for example, contain salt crystals.

The compositions of the invention contain enzyme material. The enzymes can be selected from lipases, amylases, proteases (10-1000 GU/mg), cellulases and mixtures thereof. Various types of proteolytic enzymes and amylolytic enzymes are known in the art and are commercially available. They can be incorporated as "prills", "marumen" or suspensions. The enzyme levels range from 1 to 5% by weight of the composition. Enzymes often contain propylene glycol/water mixtures or the like to stabilize them. The enzyme stability after 3 months storage at 37°C is preferably higher than 50%, more preferably higher than 80% and most preferably higher than 90%. Preferably the enzyme solution contains no more than 10% by weight of water-soluble electrolyte material.

The introduction of small amounts of water into the liquids of the invention proved in some cases to be beneficial for the stability of the liquid, whereas it was surprisingly found that it did not negatively affect either the viscosity of the composition or the stability of the enzymes.

Liquid phase

The liquid phase of the detergent composition of the invention may comprise water, surfactant material and solvent material.

The liquids according to the invention frequently and preferably comprise a liquid nonionic surfactant as the main component and normally consist of a water-solubilizing polyalkoxylene or a mono- or dialkanolamide group in chemical combination with an organic hydrophobic group derived, for example, from fatty alcohols having 9 to 15 carbon atoms (optionally branched, for example methyl-branched), alkylphenols (preferably 12 to 20 carbon atoms) wherein the alkyl group contains 6 to 12 carbon atoms, dialkylphenols in which each alkyl group contains 6 to 12 carbon atoms, primary, secondary or tertiary aliphatic alcohols (or alkyl-capped derivatives thereof), monocarboxylic acids having 10 to 24 carbon atoms in the alkyl group and polyoxypropylenes.

C10-C20 fatty acid mono- and dialkanolamides, where the alkyloyl group has 1 to 3 carbon atoms, are also common.

In polyalkoxylene-containing surfactants, the polyalkoxylene moiety usually consists of an average of 2 to 20 groups of ethylene oxide, propylene oxide groups or mixtures thereof. The latter class includes those described in European Patent Specification EP-A-0 225 654, particularly for use as a whole or as part of the liquid phase.

Particularly preferred are those ethoxylated nonionic surfactants which are condensation products of fatty alcohols having 9 to 15 carbon atoms condensed with 3 to 7 moles of ethylene oxide. Examples of these are the condensation products of C 1-13 alcohols with 3 or 7 moles of ethylene oxide. These can be used as the only nonionic surfactant or in combination with those described in EP-A-0 225 654.

Another class of suitable nonionic surfactants includes the alkyl saccharides (polyglycosides/oligosaccharides) and in particular those described in the patent specifications US-A-3 640 998, US-A-3 346 558, US-A-4 223 129, EP-A-0 092 355, EP-A-0 099 183, EP-A-0 070 074, EP-A-0 070 075, EP-A-0 070 076, EP-A-0 070 077, EP-A-0 075 994, EP- A-0 075 995 and EP-A-0 075 996.

A typical mixture of surfactants includes a nonionic and/or non-alkoxylated anionic and/or alkoxylated anionic surfactant. Mixtures of different nonionic detergent surfactants can be used and mixtures with other detergent surfactants such as anionic, cationic or ampholytic surfactants and soaps can also be used. Surfactants are described in "Surface Active Agents" Volume I, by Schwartz & Perry, Interscience 1949 and "Surface Active Agents" Volume II, by Schwartz, Perry & Berch (Interscience 1958) in the current edition of "McCutcheon's Emulsifiers & Detergents", published by the McCutcheon Division of Manufacturing Confectioners Company, or in "Tensid-Taschenbuch", H. Stache, 2nd edition, Carl Hanser Verlag, Munich & Vienna. The compositions according to the invention comprise surfactant material, the proportion preferably being at most 97%, more preferably at most 95%, particularly preferably at most 94%, and the proportion being at least 70%, more preferably at least 80% by weight.

Solvent material, and particularly esters of C1-6 carboxylic acid and/or polycarboxylic acid and an alcohol, selected from dihydric alcohols, ether alcohols and sterically hindered alcohols, may be included in the compositions of the invention. Preferably, the ester is present in amounts of from 0.01 to 50% by weight of the composition. A preferred ester material is propylene glycol diacetate.

Other liquid material that may be present in the liquid phase includes liquid bleach precursors, such as glycerol triacetate, and solvent material such as ethanol and dodecanol.

For the purpose of the invention, liquid detergent compositions are defined as being in a liquid to paste form, preferably in a liquid form. The viscosity of the compositions is preferably a maximum of 2500 mPa.s, more preferably a maximum of 1500 mPa.s, most preferably a maximum of 1000 mPa.s at 21 s⊃min;1 at 25°C.

Preferably, the fluids of the invention have a physical stability of no or minimal phase separation after 2 months at 37°C. More preferably, the phase separation is less than 2 mm per month at 37°C.

Solid phase

Preferably, the compositions of the invention comprise from 0.1 to 20% by weight of a solid phase. Preferably, the level of solid phase is at least 0.2%, more preferably at least 0.5% and preferably a maximum of 15%, more preferably less than 10% and most preferably a maximum of 9%, most preferably a maximum of 5% by weight of the composition. We have found that these low levels of solid particles are beneficial not only for the viscosity of the liquid but also for the physical stability, whereas one would expect that higher levels of dispersed solid particles would be required.

Other ingredients

The compositions of the invention may comprise electrolyte material. However, we have found that electrolyte can affect the properties of the compositions of the invention, particularly during storage. Therefore, the compositions of the invention preferably comprise Electrolyte in a concentration of less than 1% by weight of the composition.

In particular, we have found that water-soluble electrolyte can affect the composition properties. Examples of such electrolytes are chloride, sulfate, carbonate and hydroxide. Accordingly, the composition preferably comprises electrolyte, particularly soluble electrolyte, at a concentration of below 1%, more preferably below 0.3%, preferably below 0.2% by weight of the composition.

Furthermore, we have found that the preferred weight ratio of water:electrolyte in the compositions of the invention is more than 1:0.03, more preferably more than 1:0.02.

Other ingredients include the remaining ingredients that may be used in liquid detergent products, such as fabric conditioning agents, abrasive materials, bleaches, builders, enzyme stabilising agents (if required), fluorescers, perfumes (including deodorant perfumes), microbicides, soil suspending agents, anti-redeposition agents, corrosion inhibitors and foam reducers.

The total amount of the fluorescent agent or agents used in the detergent composition is preferably 0.1 to 10%, more preferably 0.02 to 2% by weight.

If it is desired to use antiredeposition agents in the liquid detergent products, the amount thereof will normally be in the range of 0.1% to 5% by weight, preferably 0.2% to 2.5% by weight of the total liquid composition. Preferably, antiredeposition agents include carboxy derivatives of sugars and celluloses, for example sodium carboxyalkyl (e.g. methyl) cellulose, anionic polyelectrolytes, in particular polymeric aliphatic carboxylates or organic phosphonates.

processing

As stated, the present invention further relates to a process for preparing liquids comprising less than 12% by weight of water, enzymes, surfactants, silicone and hydrophilic silica as described above by adding the enzyme in the form of an aqueous solution.

The enzymes are preferably added after the dispersion of silicon dioxide and silicones is complete and at temperatures of 30ºC or lower.

Preferably, the enzyme is precipitated in situ. We have found that this results in small enzyme particles that can be stably incorporated into the hydrophilic silica structure.

The following examples are provided to further illustrate and describe the invention and are not intended to limit the invention in any way.

EXAMPLES example 1

The following liquids were prepared:

1) Marlipal 013-89TM (90%)

2) Marlipal 013-30TM (100%)

3) Savinase 16.OSLTM (enzyme slurry)

4) Savinase 16.0LDXTM (aqueous/propylene glycol enzyme preparation)

5) DB100 SiliconesTM

6) As measured with a Haake MVIIST after 5 minutes

Composition 1 was prepared by dispersing the silica and silicones in the mixture of non-ionic surfactants and water. Then the aqueous enzyme solution was added and the enzyme was precipitated in situ at a temperature below 30ºC.

Composition A was unstable, whereas Composition 1 according to the present invention is stable, showed no settling, no sediment, no clear layer separation and good dispersibility.

Example 2

The following liquid was prepared by adding the ingredients in the order listed:

1) Marlipal 013-89TM (90%)

2) Marlipal 013-30TM (100%)

3) DB100 SiliconesTM

4) Savinase 16.OLDXTM (aqueous enzyme solution)

5) CBS/X Fluorescent AgentTM

6) Blancophor MBBH766TM

7) Blanose 7M1TM, by Aqualon (Hercules)

8) GabrosaTM, from AKZO Nobel

9) Viscosity between 100-350 mPa.s at 21 s⊃min;¹ at 25ºC

Compositions 1, 2, 3 and 4 showed good stability during storage, whereas composition B, which contained higher levels of electrolyte, showed instability after 2 days of storage.

Example 3

The following liquid was prepared by adding the ingredients in the order listed: Composition

1) Marlipal 013-89TM (90%)

2) Marlipal 013-30TM (100%)

3) DB100 SiliconesTM

4) Savinase 16.0LDXTM (aqueous enzyme solution)

5) Blanose 7M1TM, by Aqualon (Hercules)

6) Viscosity between 100-350 mPa.s at 21 s-1 at 25ºC.

The four compositions showed good stability after 3 weeks of storage at 37ºC.

Claims (6)

1. A liquid detergent composition comprising water, surfactant material, silicone material and 0.05 to 20 weight percent of a dispersed solid phase comprising hydrophilic silica material and enzyme material, characterized in that the composition comprises less than 12 weight percent of the water, at least 70 weight percent of the surfactant material and 1-5 weight percent of the enzyme material. 2. The composition of claim 1, wherein the composition further comprises a fluorescent agent in an amount of 0.01 to 10 weight percent. 3. A composition according to claims 1 or 2, wherein the composition further comprises an antiredeposition agent in an amount of 0.1 to 5% by weight. 4. A composition according to any one of claims 1 to 3, wherein the composition comprises electrolyte material at a concentration of less than 1 weight percent. 5. A composition according to any one of claims 1 to 4, wherein the composition comprises at least 0.5% by weight water. 6. A process for preparing a liquid detergent composition according to any one of claims 1-5, which process comprises the step of adding the enzyme material in the form of an aqueous solution to a liquid composition, which comprises silicone material, hydrophilic silicon dioxide, surfactant material and water.