Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/37—Polymers
  • C11D3/3703—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • C11D3/373—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds containing silicones
  • C11D3/3738—Alkoxylated silicones
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
  • C11D1/66—Non-ionic compounds
  • C11D1/82—Compounds containing silicon
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/0005—Other compounding ingredients characterised by their effect
  • C11D3/0026—Low foaming or foam regulating compositions
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/37—Polymers
  • C11D3/3703—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • C11D3/373—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds containing silicones

Definitions

• the present invention relates to liquid detergent compositions containing an antifoam agent. More in particular, the present invention relates to liquid detergent compositions comprising a dispersible silicone antifoam agent.
• the present invention relates to a dispersible antifoam agent containing a silicone for incorporation into concentrated liquid detergents wherein the antifoam agent provides a stable, uniform detergent with controlled foaming behavior.
• a defoamer or antifoam agent is a material which, when added in low concentration to a foaming liquid controls the foam problem.
• the defoamer equilibrates the rate of foam collapse with the rate of foam formation.
• Such materials remove unsightly and troublesome surface foam, improve filtration, watering, washing, and drainage, of various types of suspensions, mixtures, and slurries.
• Defoamers have found application traditionally in such areas of use as the pulp and paper industry, paints and latex, coating processes, fertilizers, textiles, fermentation processes, metal working, adhesive, caulk and polymer manufacture, the sugar beet industry, oil well cement, cleaning compounds, cooling towers, and in chemical processes of varied description, such as municipal and industrial primary and secondary waste water treatment facilities. It is essential for a defoamer that it be inert and not capable of reacting with the product or system in which it is used, and that it have no adverse affect on the product or system.
• a silicone defoamer or silicone antifoam agent in a liquid detergent is not new, however, it is uncommon. The reason is that it is particularly difficult to homogeneously disperse antifoam formulations into aqueous mediums such as liquid detergents.
• a liquid detergent is a complex chemical formulation and often the complexity of such formulations hinder a homogeneous dispersion of an antifoam composition in the detergent. The result is often loss of uniformity, as well as flocculates of antifoam accumulating at the surface of the detergent.
• One of the overriding trends of today is the move toward more concentrated liquid detergents. This shift offers the inherent efficiency of manufacture and use of liquid formulas, such as pumpability and easy measuring of liquids, while reducing the burden of packaging and shipping costs. This trend is occurring in both the consumer market products and in industrial formulations.
• Raleigh, in United States Patent No. 4,005,044 discloses an antifoam composition and method with a silazane treated precipitated silica added to aqueous emulsions of silicone oil with organic nonionic surfactants. Raleigh particularly emphasizes hexamethyldisilazane-treated silica and teaches that especially stable emulsions are formed.
• Koerner et al. in United States Patent No. 4,274,977, discloses a defoamer composition having a high dispersion stability composed of a water-insoluble defoamer oil, a water soluble emulsifier which is insoluble in the defoamer oil, and a mixture of a finely divided hydrophobic and hydrophilic silica. It is taught that the compositions allow for the production of exceptionally stable dispersions.
• Keil in U.S. Patent No. 3,784,479, discloses foam control compositions which consist essentially of a base oil selected from polyoxypropylene polymers,polyoxypropylene-polyoxyethylene copolymers or siloxane-glycol copolymers, a foam control agent comprising a liquid dimethylpolysiloxane and silica filler, and a dispersing agent which consists of a copolymer of a siloxane resin and polyoxyalkylene polymer.
• a base oil selected from polyoxypropylene polymers,polyoxypropylene-polyoxyethylene copolymers or siloxane-glycol copolymers
• a foam control agent comprising a liquid dimethylpolysiloxane and silica filler
• a dispersing agent which consists of a copolymer of a siloxane resin and polyoxyalkylene polymer.
• Keil in United States Patent No. 3,984,347, discloses foam control compositions which consist essentially of a base oil selected from polyoxypropylene polymers, polyoxypropylene-polyoxyethylene copolymers or siloxane-glycol copolymers, a foam control agent comprising a liquid dimethylpolysiloxane and silica filler and a siloxane copolymer dispersing agent.
• the dispersing agent consists of a copolymer of a dimethylpolysiloxane polymer and a polyoxyalkylene polymer.
• Japanese O.P.I. No. 139,107/81, published October 30, 1981 teaches a self-emulsifying type defoaming agent which is said to have excellent foam-suppressing and breaking capability regardless of temperature and pH of a liquid to be treated and the storage period to which it is subjected.
• This agent is composed of a silicone copolymer having diorganosiloxane and organo- oxyalkylenesiloxane units in the copolymer chain.
• Aizawa et al. in United States Patent No. 4,639,489 and United States Patent No. 4,749,740, the disclosures of which are hereby incorporated by reference, teach a method for producing a silicone defoamer composition wherein a complex mixture of polyorganosiloxanes, filler, a resinous siloxane and a catalyst to promote reaction of the other components are heated together at 50°C to 300°C.
• the abovementioned complex silicone mixture additionally contains at least 0.2 weight parts of an organic compound having at least one group selected from COR, -COOR' or -(OR'') n - wherein R and R' are hydrogen or a monovalent hydrocarbon group, R'' is a divalent hydrocarbon group having 2 to 6 carbon atoms and the average value of n is greater than one.
• R and R' are hydrogen or a monovalent hydrocarbon group
• R'' is a divalent hydrocarbon group having 2 to 6 carbon atoms and the average value of n is greater than one.
• T. Miura emphasizes the need to react all the ingredients, including a catalyst, at elevated temperature to obtain the desired antifoam agent.
• a foam control composition which gives improved performance in high foaming detergent compositions which comprises (A) a liquid siloxane having a viscosity at 25°C of at least 7 x 10 ⁇ 3 m2/s and which was obtained by mixing and heating a triorganosiloxane-endblocked polydiorganosiloxane, a polydiorganosiloxane having at least one terminal silanol group and an organosiloxane resin, comprising monovalent and tetravalent siloxy units and having at least one silanol group per molecule, and (B) a finely divided filler having its surface made hydrophobic.
• John et al. further describes a method for making the foam control compositions and detergent compositions containing said foam control compositions.
• Starch in U.S. Patent No. 4,983,316 discloses a dispersible antifoam composition for providing controlled foaming liquid laundry detergent formulations and wherein there is provided a non-aqueous emulsion of primary and secondary silicone antifoam agents, at least one nonionic silicone surfactant for emulsifying the primary and secondary antifoaming agents in a solvent, a first organic surfactant dispersing agent for assisting in dispersing the emulsified primary and secondary antifoaming agents in the liquid laundry detergents, and a second dispersing agent of a nonionic difunctional block-copolymer terminating in primary hydroxyl groups for further assisting in dispersing the emulsified primary and secondary antifoam agents in the liquid laundry detergent.
• a liquid laundry detergent composition containing the composition described immediately above is also disclosed.
• McGee et al. in European Patent Application No. 341,952, published November 15, 1989 discloses a combination of the above mentioned compositions of Aizawa et al. with particular silicone glycol compounds to provide improved antifoams for use in high pH aqueous systems, particularly pulp mill liquors. McGee et al. further describes that addition of a silica filler has been found to impart increased stability to the compositions and to dispersions thereof.
• the antifoam agent is an emulsion gelled silicone composition prepared by first dispersing a curable liquid organopolysiloxane composition in a liquid continuous phase to form an emulsion and then curing the liquid silicone organopolysiloxane in-situ to a gelled state.
• Hill et al. further discloses that the compositions of the invention find particular utility in the control of foam in aqueous detergent systems.
• the present invention offers a very dramatic improvement in stability against coalescence and aggregation in concentrated detergent liquids.
• the present invention can improve the uniformity of dispersion of the antifoam, provide more uniform and reproducible foam control delivery, and avoid the formation of unsightly lumps of aggregated antifoam droplets that may tend to sink or float during storage thus aiding in their stability and providing a far less visible form of the antifoam allowing for the formulation of transparent liquids if needed. Therefore, improved foam control can be obtained if compositions such as those described in Aizawa et al. are modified to offer improved combinations of antifoam compositions, non-aqueous phases, additonal fillers, and especially through the use of particulate stabilizers.
• a non-aqueous liquid continuous phase and a moderately hydrophobic particulate stabilizing aid when combined with and incorporated into an antifoam formulation of U.S. Patent Nos. 4,639,489, 4,749,740, or EP0217501 cited supra, render the antifoam dispersible and stable in aqueous media such as liquid detergents, and especially concentrated liquid detergents, and therefore solve the problem of dispersibility of previously disclosed antifoam formulations.
• liquid detergent compositions comprising an antifoam agent, said agent consisting essentially of: (I) a reaction product prepared by reacting at a temperature of 50°C to 300°C: (i) 100 parts by weight of at least one polyorganosiloxane selected from the group consisting of (A) a polyorganosiloxane having a viscosity of about 20 to 100,000 cS at 25°C and being expressed by the general formula R1 a SiO (4-a)/2 in which R1 is a monovalent hydrocarbon or halogenated hydrocarbon group having 1 to 10 carbon atoms and a has an average value of 1.9 to 2.2 and (B) a polyorganosiloxane having a viscosity of 200 to about 100 million cS at 25°C expressed by the general formula R2 b (R3O) c SiO (4-b-c)/2 in which R2 is a monovalent hydrocarbon or halogenated hydrocarbon group having 1 to 10 carbon atoms,
• Another object of this invention is to provide a dispersible silicone antifoam composition offering much improved stability against aggregation and separation and ease of dispersibility. It is also an object of this invention to greatly increase antifoam droplet stability against aggregation during storage in the highly concentrated liquid detergent medium. An additional object of this invention is to improve stability against coalescence and aggregation in concentrated detergent liquids. A further object of this invention is to improve the uniformity of dispersion of a silicone antifoam and avoid the formation of lumps of aggregated antifoam droplets that may tend to sink or float during storage.
• the antifoam agent of this invention consists essentially of (I) a reaction product prepared according to the disclosure of Aizawa et al., cited supra, (II) a nonaqueous liquid continuous phase, and (III) a moderately hydrophobic particulate stabilizing aid.
• Component (I) of the antifoam agent according to the present invention is a reaction product of (i) a polyorganosiloxane, (ii) a silicon compound, (iii) at least one finely divided filler and (iv) a catalytic amount of a compound for promoting the reaction of the other components.
• Component (i) may be selected from (A) polyorganosiloxanes expressed by the general formula R1 a SiO (4-a)/2 and having a viscosity of 20 to 100,000 centistokes (cS) at 25°C.
• the organo groups R1 of the polyorganosiloxane (A) are the same or different monovalent hydrocarbon or halogenated hydrocarbon groups having one to ten carbon atoms. Specific examples thereof are well known in the silicone industry and include methyl, ethyl, propyl, butyl, octyl, trifluoropropyl, phenyl, 2-phenylethyl and vinyl groups. The methyl group is particularly preferred.
• polyorganosiloxane (A) is a trimethylsilyl- terminated polydimethylsiloxane having a viscosity of about 350 to 15,000 cS at 25°C.
• component (i) may be selected from (B) polyorganosiloxanes expressed by the general formula R2 b (R3O) c SiO (4-b-c)/2 and having a viscosity of 200 to 100 million centistokes at 25°C wherein R2 is independently selected from the monovalent hydrocarbon or halogenated hydrocarbon groups designated for group R1, R3 is a hydrogen atom or R2, and the -OR3 group is present at least at one end of the molecular chain of the polyorganosiloxane.
• the value of b is between 1.9 to 2.2 and c is has a value so as to provide at least one -OR3 group per molecule.
• polyorganosiloxane (B) is a hydroxyl-terminated polydimethylsiloxane having a viscosity of about 1,000 to 50,000 cS at 25°C.
• Component (i) may also be a mixture of (A) and (B) in any proportion.
• Component (ii) is at least one silicon compound selected from (a) to (d), (a) an organosilicon compound of the general formula R4 d SiX 4-d wherein R4 is a monovalent hydrocarbon group having one to five carbon atoms, X is a hydrolyzable group, such as -OR5 or - OR6OR7, in which R6 is a divalent hydrocarbon group having one to five carbon atoms and R5 and R7 are each hydrogen or a monovalent hydrocarbon group having one to five carbon atoms, the average value of d not exceeding 1; (b) a partially hydrolyzed condensate of the compound (a); (c) a siloxane resin consisting essentially of (CH3)3SiO 1/2 and SiO2 units and having a (CH3)3SiO 1/2 /SiO2 ratio of 0.4/1 to 1.2/1; and (d) a condensate of the siloxane resin (c) with the compound (a) or (b).
• R4
• component (ii) is selected from either an alkyl polysilicate wherein the alkyl group has one to five carbon atoms, such as methyl polysilicate, ethyl polysilicate and propyl polysilicate, or the siloxane resin (c).
• component (ii) is either ethyl polysilicate or a siloxane resin copolymer consisting essentially of (CH3)3SiO 1/2 units and SiO2 units in a molar ratio of 0.4:1 to 1.2:1.
• Component (iii) is optional and is at least one finely divided filler such as fumed TiO2, Al2O3, Al2O3/SiO2, ZrO2/SiO2 and SiO2.
• Silica (SiO2) can be produced by a dry method such as the thermal decomposition of a silicon halide or the reaction of a substance containing silicic acid under heat, or silica can be produced by a wet method such as the decomposition of a metal salt of silicic acid, e.g., sodium silicate, by an acid or the aerogel method.
• the filler is selected from silicas having a surface area of about 50 to 300 m2/g. Fumed TiO2, Al2O3, and Al2O3/SiO2 can be prepared by the well-known process of burning TiCl4, AlCl3, and SiCl4 and mixtures thereof. Specific examples of this filler include zirconium silica hydrogels, and hydrophilic or hydrophobic silica.
• finely divided filler excludes materials such as mined quartz or micronized quartz.
• the finely divided filler is a compatiblized filler such as hydrophobically modified finely divided silica which has been modified by surface reaction with any of the various treating agents to produce a well treated, hydrophobic surface. This can be accomplished in-situ or by prior treatment.
• Component (iii) can be 0 parts by weight in Reaction Product (I) or can be from greater than zero to 30 parts by weight per 100 parts by weight of Reaction Product (I).
• Component (iv) is a compound used as a catalyst for promoting the reaction of the other components. It is preferably selected from siloxane equilibration and/or silanol-condensing catalysts such as alkali metal hydroxides, alkali metal silanolates, alkali metal alkoxides, quaternary ammonium hydroxides and silanolates, quaternary phosphonium hydroxides and silanolates and metal salts of organic acids. It is preferred that the catalyst is potassium silanolate.
• the reaction product may optionally contain component (v), a polyorganosiloxane expressed by the general formula R8 e (R9O) f SiO (4-e-f)/2 and having a viscosity of 5 to 200 cS at 25°C wherein R8 is a monovalent hydrocarbon or halogenated hydrocarbon group having one to ten carbon atoms and R9 is hydrogen or a monovalent hydrocarbon group having one to ten carbon atoms.
• the value of e is between 1.9 and 2.2 and f has a value so as to provide two or more -OR9 groups in each molecule.
• component (v) is a hydroxyl-terminated polydimethylsiloxane having a viscosity of about 10 to 50 cS at 25°C. It is preferred that component (v) is added when filler (iii) is a hydrophilic silica.
• a mixture of components (i) to (iv), optionally containing component (v), is reacted under heat to produce the reaction product, the proportions of the various components being:
• the reaction product (I) is prepared by first mixing components (i) and (ii) and heating this blend to about 110 to 120°C and then adding catalyst (iv). Finely divided filler (iii), if desired, is then uniformly mixed in using an appropriate dispersing device, such as a homomixer, colloid mill or triple roll mill. The resulting mixture is heated at a temperature of 50°C to 300°C, preferably 100°C to 300°C, and reacted for one to eight hours, although the reaction time varies depending on the temperature. If component (v) is to be employed in the composition, it is generally added after the filler (iii).
• reaction product (I) preferably comprises a diorganopolysiloxane and a silicon compound, this combination optionally containing a filler such as silica.
• These systems contain a mixture of a trimethylsilyl- terminated polydimethylsiloxane and a diorganopolysiloxane having silicon-bonded hydroxyl groups or silicon-bonded alkoxy groups along its main chain or at its chain ends, said alkoxy groups having from 1 to 6 carbon atoms.
• the silicon compound (ii) acts as a crosslinker for the diorganopolysiloxane by reacting with the functionality of the latter.
• the above diorganopolysiloxane is either a linear or a branched polymer or copolymer of siloxane units selected from dimethylsiloxane units, methylphenylsiloxane units or methyltrifluoropropylsiloxane units.
• the diorganopolysiloxane of component (A) is a polydimethylsiloxane containing Si-bonded hydroxyl or methoxy functionality.
• the above mentioned silicon compound (ii) is preferably a siloxane resin consisting essentially of (CH3)3SiO 1/2 and SiO2 units and having a molar ratio of (CH3)3SiO 1/2 /SiO2 between 0.4:1 and 1.2:1.
• the latter resin may be prepared according to methods taught in, e.g., United States Patent No. 2,676,182 to Daudt et al. and typically contains from about 0.5 to about 3 weight percent of hydroxyl groups.
• a highly preferred component (I) is a homogeneous blend of a hydroxyl-terminated polydimethylsiloxane and a a trimethylsilyl- terminated polydimethylsiloxane having a viscosity in the range of about 1,000 to 50,000 cS at 25°C, a siloxane resin having a molar ratio of (CH3)3SiO 1/2 /SiO2 units of from 0.4:1 to 1.2:1, and a potassium silanolate catalyst reacted at a temperature of 50 to 300°C.
• the nonaqueous liquid continuous phase (II) of the antifoam agent according to the present invention may be a non-reactive organic composition.
• the term "non-reactive” is intended to convey the restriction that this component be generally compatible with the silicone antifoam (I), as detailed above. Since component (II) is designed to be a distinct phase, its character is further restricted to liquids which are essentially immiscible with the particular silicone antifoam (I).
• the nonaqueous liquid continuous phase of component (II) can be selected from the group consisting of ethylene glycol, propylene glycol, polypropylene glycol, polyethylene glycol, copolymers of either a random or block type, of propylene and ethylene glycols and condensates with polyols such as glycerol.
• Additional nonaqueous liquid phases of this invention include a wide range of nonionic organic surfactants such as alcohol alkoxylates or alkylphenol alkoxylates.
• the nonaqueous phase is selected for ease of dispersibility and solubility in the liquid detergent medium since insufficient solubility can lead to poor stability and poor performance of the antifoam in the liquid detergent. Consideration is also made for compatibility of the liquid with the nonionic silicone surfactants which may be used in preparing the antifoam emulsion described hereinbelow.
• the liquids are further selected based on their specific gravity with a close match relative to the antifoam particles being preferable.
• component (II) has a viscosity below about 10,000 cS at 25°C. A closer match of the continuous phase specific gravity to the antifoam droplets may be obtained by judiciously selecting and blending two or more nonaqueous liquids to make component (II).
• liquid continuous phase (II) it is preferable that about 25 to 900 parts by weight of liquid continuous phase (II) be used per 100 parts by weight of defoamer reaction product (I). It is highly preferred for purposes of the present invention that 100 to 400 parts by weight of liquid continuous phase (II) be used per 100 parts by weight of defoamer reaction product (I).
• Component (III) of the antifoam agent according to the present invention is a moderately hydrophobic particulate stabilizing aid wherein the particulate is a very fine particle size silica.
• component (III) of the present invention is silica and is of the fumed or precipitated types but not limited to this type, having a B.E.T. surface area preferably from 50 to 500 square meters per gram, the surface of which has been incompletely treated with hydrophobing agents.
• hydrophobing treatment level is the analysis of bound carbon on the silica.
• the great majority of hydrophobing agents used today incorporate carbon as a critical component of their hydrophobic groups and as such carbon contributes directly to the hydrophobic layer on the silica surface.
• Specific Loading to describe the micrograms of carbon bound per square meter of surface area.
• the bound carbon may be measured by any of a number of analytical techniques but should be a directly measured value.
• Aerosil R R 972 (fumed silica that has been treated to a moderate level with dichlorodimethylsilane, having about 110 m2/g BET surface area, Degussa Corporation, Ridgefield Park, N.J.). This material is prepared from a fumed silica having surface area of 130 m2/g. The silica is treated with dimethyldichlorosilane at about 500°C with the treating level being controlled to provide less than complete methylation of the surface. In the case of Aerosil R R 972 it is estimated that 70% of the surface hydroxyl groups present on the original silica have been methylated leaving approximately 30 % untreated.
• this silica has a 70/30 or a 2.33 treated/untreated silanol ratio.
• the untreated hydroxyls are hydrophilic and are capable of hydrogen bonding with polar substances such as water.
• the alkylated portion of the surface is non-polar in nature and hydrophobic. A controlled level of treatment will provide a moderately treated silica with a balance between the hydrophobic alkylated surface and the hydrophilic untreated surface.
• Particulates having a controlled level of hydrophobic treatment prior to utilization are preferred as component (III) in the present invention.
• Any of several known treating methods may be employed in prior treatment of the silica for component (III).
• fumed silica can be treated with dimethyldichlorosilane to affix dimethylsilane groups on the surface of the silica.
• the hydrophobing agents herein are any of those well known to the art which provide organosilyl reaction products bound to the silica surface. Common examples of hydrophobing agents are silanes, siloxanes, or silazanes.
• modification is carried out by procedures well known to the art, for example, by reaction of the silica surface with trialkylchlorosilane, dialkyldichlorosilane, octaalkylcyclotetras iloxane, or hexaalkyldisilazane, or hexaalkyltrisilazane under suitable conditions.
• Hydrophobing agents such as polydimethylsiloxane are not preferred for this invention unless special care is taken to limit the amount of hydrophobic material placed on the silica surface and its distribution.
• the stabilizing aid of component (III) be a silica whose surface has been hydrophobically modified to provide a surface composition having a treated/untreated surface silanol ratio such that it has a Methanol Wettability of from 30 to 70 percent. It is highly preferred in the present invention that component (III) have a Methanol Wettability of from 35 to 55 percent.
• silica of component (III) are hypothesized to have influencing factors on their relative utility as stabilizing aids. Without limiting the present invention to any particular theory, it is believed that the physical and chemical makeup of the solid's surface is important to the utility of the particulates in the present invention in that it controls the wetting behavior of the solid. Thus, in addition to having a controlled level of surface treatment, the uniformity of distribution of the hydrophobic materials on the surface and the surface roughness and porosity of the solid is thought to impact wetting behavior, especially wetting hysteresis.
• silicas are thought to consist of primary particles linked together into aggregates which are assembled into agglomerates through physical interactions. Breakup of agglomerates into smaller particles may be one component in the relative efficiency of the particulate stabilization and should be a component of processing optimization.
• an effective amount of the stabilizing aid of the present invention is required for the compositions of the present invention to display beneficial effects in liquid detergent systems.
• the antifoam agent according to the present invention additionally comprise (IV) at least one nonionic silicone surfactant.
• the nonionic silicone surfactant is preferably a material including a trimethylsilyl endcapped polysilicate which has been condensed with a polyalkylene glycol or diester in a solvent, or a block copolymer of polydimethylsiloxane and polyalkylene oxide.
• a sufficient quantity of at least one nonionic silicone surfactant is employed to aid emulsification of silicone antifoam component (I) described hereinabove in the nonaqueous liquid continuous phase component (II) described hereinabove.
• surfactant Generally, from about 1 to 40 parts by weight of surfactant is used for each 100 parts by weight of component (I).
• surfactants are well known in the art and are exemplified by the "dispersing agents" disclosed by Keil in United States Patent numbers 3,784,479 and 3,984,347, the disclosures of which are hereby incorporated by reference to teach said surfactants.
• the surfactants may best be processed from a solvent such as a polyalkylene glycol or copolymers thereof, cyclic silicones, or an organic solvent such as xylene.
• the antifoam agent according to the present invention may also additionally comprise (V) a level of a nonreinforcing inorganic filler mixed internally to component (I) to increase its density to match the density of component (II) or of the liquid detergent, and thus to reduce the rate of settling of antifoam particles in the liquid medium.
• a nonreinforcing inorganic filler is added to component (I) after the reaction is complete as it is cooling.
• a wide variety of materials may be used as an inorganic filler. Specific examples of these materials are ground, micronized, or seived inorganic compounds or minerals either naturally occurring or artificial. One requirement is that the particle size be small relative to the antifoam droplets to provide for more uniform density distribution between droplets. To attain high densities needed for maximum efficiency, very dense or crystalline materials may be preferred.
• Preferred as the nonreinforcing inorganic filler (V) for the antifoam agents according to the present invention are Min-u-sil R ground crystalline silicas (available from U.S.
• Silica Company, Berkeley Springs, WV microcystalline novaculite such as Novacite R or surface modified forms such as Novakup R (Malvern Minerals Company Hot Springs National Park, AR), calcium carbonate, antimony oxides, wollastonite, titanium oxides or their surface modified forms available commercially as Carbokup R , Monokup R , Wollastokup R , or Trikup R , (Malvern Minerals Company, Hot Springs National Park, AR).
• inorganic filler (V) inorganic filler (V) in the compositions of the present invention however this list is not exhaustive.
• higher levels of finely divided filler (iii) described hereinabove normally used in antifoams may be used at levels higher than necessary just for antifoaming efficacy, reducing or obviating the need for an additional nonreinforcing filler.
• An additional advantage in clarity or appearance of the defoaming component may be realized. This approach may be limited by any loss in antifoam efficacy due to overloading of the reaction product compound. Another limiting factor in this approach is that addition of large amounts of these materials will increase the viscosity of the defoaming component (I) and may hinder processing, emulsification, and/or performance of the antifoam.
• the foam control agents of the present invention may also contain adjuvants such as corrosion inhibitors and dyes.
• the antifoam agent according to the present invention may be prepared by homogeneously mixing, without heating or further catalysis, components (I), (II), and (III) and any optional components, using any suitable mixing means such as a spatula, mechanical stirrers, in-line mixing systems containing baffles, blades, or any of the like mixing surfaces including powered in-line mixers or homogenizers, a drum roller, a three-roll mill, a sigma blade mixer, a bread dough mixer, and a two roll mill.
• any suitable mixing means such as a spatula, mechanical stirrers, in-line mixing systems containing baffles, blades, or any of the like mixing surfaces including powered in-line mixers or homogenizers, a drum roller, a three-roll mill, a sigma blade mixer, a bread dough mixer, and a two roll mill.
• component (I) to (III) is not critical, however it is highly preferred that components (I) and (III) not be premixed together.
• component (III) is combined with the mixture of components (I) and (II) to form an emulsion and to form a composition of the present invention.
• the particulate stabilizing aid (III) may be combined with the mixture of (I) and (II) either as a dry powder or as a premix in a portion of component (II).
• Another method for preparing the antifoam agent according to the present invention involves mixing components (II) and (III) together, and next combining component (I) with the mixture formed by (II) and (III). It is preferred that the stabilizing aid component (III) not be mixed into the silicone antifoam component (I) directly as this may cause the stabilizing aid to lose its hydrophilic character and thus reduce the effectiveness of the antifoam agent according to the present invention.
• the present invention further relates to an antifoam agent prepared by mixing (I) a reaction product, (II) a nonaqueous liquid continuous phase, and (III) an effective amount of a particulate stabilizing aid, with the proviso that components (I) and (III) are not mixed together without the presence of component (II).
• the reaction product, nonaqueous liquid continuous phase, and particulate stabilizing aid are as delineated above including preferred embodiments thereof. The amounts are also as stated hereinabove.
• Optional component (IV), i.e. at least one nonionic silicone surfactant, may be added separately to Component (I), (II), or (III), or to any combination of components (I), (II), or (III), or to the final emulsion of (I), (II), and (III).
• Preferably optional Component (V), the nonreinforcing inorganic filler, is added to component (I) after the reaction is complete as it is cooling.
• the present invention also relates to a method of making a silicone antifoam comprising the steps of mixing (I) a reaction product, (II) a nonaqueous liquid continuous phase, and (III) a moderately hydrophobic particulate stabilizing aid, with the proviso that components (I) and (III) are not mixed together without the presence of component (II).
• components (I), (II), and (III) are as delineated above including preferred embodiments thereof. The amounts are also as stated hereinabove.
• optional component (IV), i.e. at least one nonionic silicone surfactant, may be added separately to Component (I), (II), or (III), or to any combination of components (I), (II), or (III), or to the final emulsion of (I), (II), and (III).
• optional component (V), the nonreinforcing inorganic filler is added to component (I) after the reaction is complete as it is cooling.
• a liquid detergent composition comprising the compositions (I), (II) and (III), optionally (IV) and/or (V) mixed with detergent ingredients such as surfactants, builders and other optional ingredients.
• a wide range of surfactants can be used in the detergent composition of the present invention.
• Nonionic surfactants useful in the present invention are condensates of ethylene oxide with a hydrophobic moiety to provide a surfactant having an average hydrophiliclipophilic balance (HLB) in the range from 8 to 17, preferably from 9.5 to 13.5, more preferably from 10 to 12.5.
• HLB hydrophiliclipophilic balance
• the hydrophobic (lipophilic) moiety may be aliphatic or aromatic in nature and the length of the polyoxyethylene group which is condensed with any particular hydrophobic group can be readily adjusted to yield a water-soluble compound having the desired degree of balance between hydrophilic and hydrophobic elements.
• Especially preferred nonionic surfactants of this type are the C9-C15 primary alcohol ethoxylates containing 3-8 moles of ethylene oxide per mole of alcohol, particularly the C14-C15 primary alcohols containing 6-8 moles of ethylene oxide per mole of alcohol and the C12-C14 primary alcohols containing 3-5 moles of ethylene oxide per mole of alcohol.
• Nonionic surfactants comprises alkyl polyglucoside compounds of general formula RO (C n H 2n O) t Z x wherein Z is a moiety derived from glucose; R is a saturated hydrophobic alkyl group that contains from 12 to 18 carbon atoms; t is from 0 to 10 and n is 2 or 3; x is from 1.3 to 4, the compounds including less than 10% unreacted fatty alcohol and less than 50% short chain alkyl polyglucosides.
• Compounds of this type and their use in detergent are disclosed in EP-B 0 070 077, 0 075 996 and 0 094 118.
• nonionic surfactants are poly hydroxy fatty acid amide surfactants of the formula wherein R1 is H, or R1 is C1 ⁇ 4 hydrocarbyl, 2-hydroxy ethyl, 2-hydroxy propyl or a mixture thereof, R2 is C5 ⁇ 31 hydrocarbyl, and Z is a polyhydroxyhydrocarbyl having a linear hydrocarbyl chain with at least 3 hydroxyls directly connected to the chain, or an alkoxylated derivative thereof.
• R1 is methyl
• R2 is a straight C11 ⁇ 15 alkyl or alkenyl chain such as coconut alkyl or mixtures thereof
• Z is derived from a reducing sugar such as glucose, fructose, maltose, lactose, in a reductive amination reaction.
• the compositions according to the present invention may further comprise a builder system.
• Any conventional builder system is suitable for use herein including aluminosilicate materials, silicates, polycarboxylates and fatty acids, materials such as ethylenediamine tetraacetate, metal ion sequestrants such as aminopolyphosphonates, particularly ethylenediamine tetramethylene phosphonic acid and diethylene triamine pentamethylenephosphonic acid.
• phosphate builders can also be used herein. Suitable builders can be an inorganic ion exchange material, commonly an inorganic hydrated aluminosilicate material, more particularly a hydrated synthetic zeolite such as hydrated zeolite A, X, B or HS.
• SKS-6 is a crystalline layered silicate consisting of sodium silicate (Na2Si2O5).
• Suitable polycarboxylates builders for use herein include citric acid, preferably in the form of a water-soluble salt, derivatives of succinic acid of the formula R-CH(COOH)CH2(COOH) wherein R is C10-20 alkyl or alkenyl, preferably C12-16, or wherein R can be substituted with hydroxyl, sulfo sulfoxyl or sulfone substituents.
• lauryl succinate myristyl succinate, palmityl succinate2-dodecenylsuccinate, 2-tetradecenyl succinate.
• Succinate builders are preferably used in the form of their water-soluble salts, including sodium, potassium, ammonium and alkanolammonium salts.
• suitable polycarboxylates are oxodisuccinates and mixtures of tartrate monosuccinic and tartrate disuccinic acid such as described in US 4,663,071.
• suitable fatty acid builders for use herein are saturated or unsaturated C10-18 fatty acids, as well as the corresponding soaps. Preferred saturated species have from 12 to 16 carbon atoms in the alkyl chain.
• the preferred unsaturated fatty acid is oleic acid.
• Another preferred builder system for liquid compositions is based on dodecenyl succinic acid.
• Other suitable water-soluble organic salts are the homo- or co-polymeric acids or their salts, in which the polycarboxylic acid comprises at least two carboxyl radicals separated from each other by not more than two carbon atoms. Polymers of this type are disclosed in GB-A-1,596,756. Examples of such salts are polyacrylates of MW 2000-5000 and their copolymers with maleic anhydride, such copolymers having a molecular weight of from 20,000 to 70,000, especially about 40,000.
• Detergency builder salts are normally included in amounts of from 10% to 80% by weight of the composition preferably from 20% to 70% and most usually from 30% to 60% by weight.
• detergent compositions may be employed, such enzymes and stabilizers or activators therefore, soil-suspending agents, soil-release agents, optical brighteners, abrasives, bactericides, tarnish inhibitors, coloring agents, and perfumes.
• the liquid detergent compositions according to the present invention can also be in "concentrated form", in such case, the liquid detergent compositions according to the present invention will contain a lower amount of water, compared to conventional liquid detergents.
• the water content of the concentrated liquid detergent is less than 30% , more preferably less than 20%, most preferably less than 10% by weight of the detergent composition.
• Antifoam compositions prepared in accordance with the present invention were prepared and tested in order to demonstrate their defoaming capabilities and to determine stability and performance of the antifoam compositions.
• compositions of the present invention were tested in a concentrated liquid detergent.
• the antifoam agents according to the present invention and the comparative compositions were tested for collar, Aggregation, and Stability.
• Collar denotes the thickness of the antifoam layer collected on top of the liquid detergent around the perimeter of the bottle.
• Aggregation denotes the collection of individual antifoam droplets into flocculates or clumps that are visible by the human eye and suspended in the body of the liquid.
• Stability denotes an overall description of the emulsion stability against association with the bottle walls and the uniformity of emulsion distribution in the sample.
• POLYORGANOSILOXANE A is a trimethylsilyl endblocked polydimethylsiloxane having a viscosity of 1,000 Cs at 25°C
• POLYORGANOSILOXANE B is a hydroxyl-terminated polydimethylsiloxane having a viscosity of approximately 13,500 cS at 25°C.
• CONTINUOUS PHASE I is P15-200 R which is an ethylene oxide/propylene oxide triol copolymer with glycerin having a molecular weight of about 2,600 from Dow Chemical Company (Midland, Michigan).
• CONTINUOUS PHASE II is NEODOL R 25-7, an organic alcohol ethoxylate from Shell Chemical Chemical Company, (Houston, Texas).
• CONTINUOUS PHASE III is PEG 300, a polyethylene glycol having an average molecular weight of 300 from the Dow Chemical Company, (Midland, Michigan).
• CATALYST I A mixture of 90 g of isopropyl alcohol and 10 g of KOH mixed at 80°C for 20 minutes.
• RESIN I A 70% xylene solution of a hydroxy-functional siloxane resin copolymer consisting essentially of (CH3)3SiO 1/2 and SiO2 units having a (CH3)3SiO 1/2 /SiO2 ratio of about 0.75:1.
• FINELY DIVIDED FILLER I is SIPERNAT R D10 is a hydrophobic silica from Degussa Corp (Ridgefield Park, N.J.).
• FINELY DIVIDED FILLER II is QUSO R WR 55 is a hydrophobic precipitated silica from Degussa Corporation (Ridgefield Park, N.J.).
• STABILIZING AID I is AEROSIL R R 972 a fumed silica that has been treated to a moderate level with dichlorodimethylsilane, having about 110 m2/g BET surface area, having a methanol wettability of about 45% and is from Degussa Corp. (Ridgefield Park, N.J.).
• NONREINFORCING FILLER I is MIN-U-SIL R QUARTZ a micronized quartz having the majority of its particles smaller than 5 microns sold under the trade name Min-u-sil 5 by U.S. Silica Company (Berekely Springs, WV).
• P 4000 is a polypropylene glycol of about 4000 molecular weight from Dow Chemical Company (Midland, Mi).
• TRITON X-100 is an octylephenolxyethoxy(10)ethanol nonionic surfactant having an HLB of 13.5 and from Rohm and Hass, (Philadelphia, PA).
• PLURONIC L-101 is a block coplymer surfactant of ethylene oxide and propylene oxide having an HLB of 1 from BASF, (Parsippany, N.J.).
• SURFACTANT 1 A nonionic silicone surfactant of trimethylsilyl endcapped polysilicate prepared according to methods described by Keil in United States Patent No. 3,784,479.
• SURFACTANTS 2-5 are block copolymers of polydimethylsiloxane and polyalkylene oxide having the average structure, shown below, were used alone or as present in a solvent: wherein Me denotes methyl radical, and and the values of j, k, m, n, are shown in Table I hereinbelow.
• This antifoam contained 60 parts of POLYORGANOSILOXANE A; 29 parts of POLYORGANOSILOXANE B; 2.9 parts of ethyl polysilicate ("silicate 45" of Tama Kagaku Kogyo Co., Ltd., Japan); 4.8 parts of a potassium silanolate catalyst; 2.9 parts of Aerogel #200 Silica (Nippon Aerogel Co., Japan) having a surface area of 200 m2/g; and 4.8 parts of hydroxy-terminated polydimethylsiloxane having a viscosity of 40 cS.
• this formulation also included 0.3 parts of ethanol as part of the catalyst, 0.1 part of water adsorbed on the silica and 0.1 part of L-540 (from Union Carbide, Danbury, CT) was added. After the reaction was complete the reaction was stopped by the addition of carbon dioxide.
• REACTION PRODUCT 3 A reaction product produced by the exact method described above for REACTION PRODUCT 1 but using 10.66 parts of FINELY DIVIDED FILLER I.
• REACTION PRODUCT 4 A reaction product produced by the exact method described above for REACTION PRODUCT 2 but with the addition of 10.5 parts of FINELY DIVIDED FILLER II for every 100 parts of silicone reaction product and was added with mixing just prior the final cooling of the reaction product.
• CONCENTRATED LIQUID DETERGENT 1 a concentrated liquid detergent according to TABLE 1.
• Test Method 1 Each sample was contained in a plastic bottle which was then subjected to a thermal gradient produced when they were placed on a warm metal surface, such as the top of a thermostatic oven or a warm water bath. The metal surface was maintained at approximately 55°C which warmed the bottom of the sample. Air was free to circulate which cooled the top of the samples creating a thermal gradient from bottom to top in the sample. This gradient promoted circulation within the sample and was found to quickly promote antifoam aggregation.
• Test Method 2 Each sample was contained in a plastic bottle and the bottles were placed in a oven thermostatically controlled to 49°C.
• a non-aqueous emulsion was prepared by adding 600 parts of the above modified antifoam compound to a combination of 150 parts of SURFACTANT 1 with 810 parts of CONTINUOUS PHASE I. Stirring was supplied from a Lightin' R LabMaster IITM. mixer fitted with two airplane style stirring blades operating at 500 RPM. After about 5 hours, stirring was ceased and a particle size measurement was performed showing a mean volume average particle size of 60 microns. This mixture is designated herein as ANTIFOAM EMULSION A.
• silicas were further characterized using a methanol wettability test (Determination of the Methanol Wettability of Hydrophobic Fumed Silicas by the Multipoint Method, Method number ACM-125 from Degussa Corporation, Ridgefield Park, N.J.) in which the silica samples are shaken into a series of solutions of increasing methanol content. The solution of water/methanol at which the silica was fully wetted was determined following centrifugation of the sample for 5 minutes at 2500 RPM with a 5.75 inch radius rotor. Plotting of the sediment height as a percent of the sediment height at complete wetting allows for a multipoint approach.
• a methanol wettability test Determination of the Methanol Wettability of Hydrophobic Fumed Silicas by the Multipoint Method, Method number ACM-125 from Degussa Corporation, Ridgefield Park, N.J.
• a series of samples were prepared using the silica premixes.
• the 5 wt.% silica premix was blended with Antifoam Emulsion A to provide 0.05 to 0.4 silica to antifoam ratio and then the mixture was blended in to CONCENTRATED LIQUID DETERGENT 1 at 2 wt.%.
• the samples were observed during Testing Method 1 and were ranked according to their performance in terms of aggregation stability in Table III below. The samples were ranked from 1 to 8, with 1 indicating the best stability versus aggregation. A description of the appearance of the samples at 190 Hrs. was recorded for each sample is also listed in Table III below.
• a sample containing no stabilizer was prepared by adding an additional amount of CONTINUOUS PHASE I in place of the silica premix.
• Premix 3-1 400 g of DEFOAMER REACTION PRODUCT 3 was blended with 100g of SURFACTANT 1 to prepare Premix 3-1.
• Premix 3-2 was prepared by blending 100 g of STABILIZING AID I into 900 g of CONTINUOUS PHASE I and then mixed on the Greerco mixer-homogenizer for 1/2 hour.
• 250 g of Premix 3-1 was added to 25 g of Premix 3-2 with stirring by a mechanical mixer with two six-blade turbine agitators fixed on the shaft operating at 750 RPM for two hours and then 500 RPM for approximately 5 hours.
• This mixture was shown to have average particle size in the 20 to 100 micron range and was suitable for easy dispersion into detergent concentrates.
• a series of samples were prepared by blending an antifoam premix with a non-aqueous premix of the stabilizing particulate.
• the antifoam premix was prepared by using moderate speed mechanical stirring for about one hour to blend REACTION PRODUCT 1 and various surfactants.
• the premix containing the stabilizing particulate was prepared by sifting the silica into the non-aqueous liquid. Mixing speed was brought up to 1000 RPM for about 20 minutes. The two premixes were then combined to form the emulsion, even if only temporarily stable, by mixing the premixes at high speeds for example at 1,000 RPM for 5 minutes on Lightin R LabMaster IITM.
• a premix was made by mixing 17.5 parts of STABILIZING AID I into 402.5 parts of CONTINUOUS PHASE I with moderate mechanical stirring until the suspension was uniform. To 420 parts of this premix was added 280 parts of REACTION PRODUCT 4 with moderate stirring. The mixture was then homogenized using a Greerco mixer-homegenizer (model IL 1989) for about 30 minutes, with a cooling period, followed by another 30 minutes of homogenization.
• This emulsion designated ANTIFOAM EMULSION B, had an average particle size of about a 30 microns as estimated by microscopic examination.
• Sample A was prepared by mixing 0.1 parts of ANTIFOAM EMULSION B into 99.9 parts of CONCENTRATED LIQUID DETERGENT 1 with moderate stirring to form a uniform dispersion.
• This example compares the compositions of the present invention against compositions previously disclosed in the art.
• An antifoam 6-1 was prepared following the method of McGee et al. disclosed in European Patent Application No. 341,952 and closely followed the method outlined in Example 25 of that disclosure. Thus, 47.5 parts of REACTION PRODUCT 2 was combined with 47.5 parts of silicone surfactant 5 and 5.0 parts of FINELY DIVIDE FILLER II. Sample 1 was prepared by mixing 0.85 parts of this antifoam into 99.15 parts of CONCENTRATED LIQUID DETERGENT 1 with moderate stirring.
• Antifoam 6-2 was prepared following the method of Starch disclosed in United States Patent 4,978,471, Example II in which 1.3 parts of SILICONE SURFACTANT 1, 2.5 parts of SILICONE SURFACTANT 6, 8.3 parts of a secondary antifoam compound of trimethylsilyl-ended polydimethylsiloxane having a viscosity of 12,500 cS at 25°C.,8.3 parts of PLURONIC L-101, and 1.25 parts of TRITON X-100 were blended into 45.0 parts of P 4000 with mechanical mixing. To this combination was added 33.3 parts of REACTION PRODUCT 2 with mixing until a uniform dispersion was formed. Sample 2 was prepared by mixing 1.0 parts of this antifoam into 99 parts of CONCENTRATED LIQUID DETERGENT 1 with moderate mixing.
• Antifoam 6-3 was prepared within the spirit of the disclosure by Starch in United States Patent 4,978,471 but using a more easily dispersible liquid continuous phase, P 425, a polypropylene glycol with an average molecular weight of 425 (marketed by Dow Chemical Company, Midland, MI), in place of P 4000.
• Antifoam 6-3 was prepared by combining 1.3 parts of SILICONE SURFACTANT 1, 2.3 parts of SILICONE SURFACTANT 6, 8.3 parts of a secondary antifoam compound of trimethylsilyl-ended polydimethylsiloxane having a viscosity of 12,500 cS at 25°C., 8.3 parts of PLURONIC L-101, and 1.25 parts of TRITON X-100 in 45.0 parts of P 425 with mechanical mixing. To this combination was added 33.3 parts of REACTION PRODUCT 2 with mixing until a uniform dispersion was formed. Sample 3 was prepared by mixing 1.0 parts of this antifoam into 99 parts of CONCENTRATED LIQUID DETERGENT 1 with moderate mixing.
• Antifoams 6-4 and 6-5 were prepared following the method of Hill et al. in European Patent Application No. 499,364, by adding 0.25 parts of stannous octoate to antifoams 6-2 and 6-3, respectively, and allowing the mixture to slowly stir overnight at room temperature. Samples 4 and 5 were prepared by adding 1.0 parts of these antifoams to 99 parts of CONCENTRATED LIQUID DETERGENT 1, respectively with moderate mixing. Antifoam 6-6 was prepared by adding 60 parts of REACTION PRODUCT 2 to a combination of 7.5 parts of SURFACTANT 1 in 82.5 parts of CONTINUOUS PHASE I with moderate mechanical stirring. Stirring was maintained for 5 hours.
• Samples 1 through 7 were prepared on a 1 kg scale for the sake of the comparison and were divided into two 500 gram samples for testing. They underwent testing according to TEST METHOD 1 and TEST METHOD 2 for four days with the observations tabulated in Table V below.

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