Anti-adhesion composition for unvulcanized rubber and its use

Abstract

The object of the present invention is to provide an anti-adhesion composition for unvulcanized rubber that is excellent in wettability, anti-adhesion and disintegration properties, and a method for producing unvulcanized rubber treated with the anti-adhesion composition for unvulcanized rubber. [Solution] An anti-adhesion composition for unvulcanized rubber comprising fine particles (A) and a surfactant (B), wherein the surfactant (B) comprises a nonionic surfactant (B1) containing a nitrogen atom, and the weight ratio of the surfactant (B1) to the surfactant (B) is more than 10% by weight.

Description

[Technical Field]

[0001] This invention relates to an anti-adhesion composition for unvulcanized rubber and its use. [Background technology]

[0002] In the production and processing of rubber products, unvulcanized rubber is sometimes stored in stacks until it is moved to the next molding or vulcanization process. In this case, an anti-adhesion agent (anti-sticking agent) is used to prevent the rubber from sticking together. Anti-adhesion agents, primarily composed of inorganic powders such as bentonite or organic powders such as metal soaps, are widely used. Generally, these are applied to the rubber surface in the form of an aqueous dispersion and then dried. Application methods include spraying the aqueous dispersion or immersing the rubber surface in the aqueous dispersion.

[0003] Patent documents 1 and 2 propose anti-adhesion agents for unvulcanized rubber consisting of various combinations of powders and surfactants. Here, the anti-adhesion agent applied to the surface of the unvulcanized rubber needs to be uniformly dispersed within the rubber so as not to impair the appearance of the rubber product after vulcanization. Therefore, it is desirable to apply the agent at the lowest possible concentration, and it is also necessary that the solidified anti-adhesion agent after drying crumbles easily during the process of kneading the unvulcanized rubber. However, the anti-adhesion agent compositions for unvulcanized rubber described in Patent Documents 1 and 2 have a problem in that, when a low-concentration aqueous dispersion is used, it repels from the rubber surface, making uniform treatment impossible and resulting in insufficient anti-adhesion properties. Furthermore, the anti-adhesion agent proposed in Patent Document 1 has a problem in that the solidified product becomes extremely hard after drying, resulting in very poor disintegration properties. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2013-001720 [Patent Document 2] Japanese Patent Publication No. 2020-041089 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The object of the present invention is to provide an anti-adhesion composition for unvulcanized rubber that is excellent in wettability, anti-adhesion and disintegration properties, and a method for producing unvulcanized rubber treated with the anti-adhesion composition for unvulcanized rubber. [Means for solving the problem]

[0006] As a result of diligent research to solve the above problems, the inventors of the present invention discovered that the above problems can be solved with an anti-adhesion agent composition for unvulcanized rubber containing specific components, and thus arrived at the present invention.

[0007] In other words, the anti-adhesion composition for unvulcanized rubber of the present invention includes the following embodiments. <1> An anti-adhesion composition for unvulcanized rubber comprising fine particles (A) and a surfactant (B), wherein the surfactant (B) comprises a nonionic surfactant (B1) containing a nitrogen atom, and the weight ratio of the surfactant (B1) to the surfactant (B) is more than 10% by weight. <2> The amount of surfactant (B) is 1 to 30 parts by weight per 100 parts by weight of fine particles (A). <1> The anti-adhesion composition for unvulcanized rubber described above. <3> The fine particles (A) are at least one selected from inorganic fine particles, fatty acid metal salts, waxes, and organic polymer fine particles. <1> or <2> The anti-adhesion composition for unvulcanized rubber described above. <4> The surfactant (B1) has a hydrocarbon group with 7 to 24 carbon atoms in its molecule. <1> ~ <3> An anti-adhesion composition for unvulcanized rubber as described in any of the following. <5> The surfactant (B1) has an oxyalkylene group having 2 to 4 carbon atoms, and the surfactant (B1) has an average of 1 to 20 oxyalkylene groups in the molecule. The antisticking agent composition for unvulcanized rubber according to any one of <1> to <4>. <6> The release agent composition according to any one of <1> to <5>, wherein the surfactant (B1) is at least one selected from a compound (B1-1) represented by the following general formula (1) and a compound (B1-2) represented by the following general formula (2).

Chemical formula

Chemical formula

Advantages of the Invention

[0008] The antisticking agent composition for unvulcanized rubber of the present invention is excellent in wettability, antisticking property, and disintegration property. The method for producing the anti-adhesion-treated unvulcanized rubber of the present invention includes a step of attaching the anti-adhesion agent composition for unvulcanized rubber to the surface of the unvulcanized rubber. Therefore, the anti-adhesion agent composition for unvulcanized rubber can adhere uniformly, and an unvulcanized rubber excellent in anti-adhesion property can be efficiently produced. Further, since the dry solidified product of the anti-adhesion agent composition for unvulcanized rubber is excellent in collapsibility, foreign matters in the unvulcanized rubber are reduced, and the productivity of the anti-adhesion-treated unvulcanized rubber is improved.

Embodiments for Carrying Out the Invention

[0009] 〔Fine Particles (A)〕 The anti-adhesion agent composition for unvulcanized rubber of the present invention (hereinafter sometimes referred to as the anti-adhesion agent composition) contains fine particles (A). The fine particles (A) form a film on the surface of the unvulcanized rubber and are components that contribute to the anti-adhesion property. The fine particles (A) are water-insoluble. In the present invention, water-insoluble means that the water solubility at 20°C is less than 1 g / 100 g. Further, the fine particles (A) may be inorganic fine particles composed of an inorganic compound, may be organic fine particles composed of an organic compound, or may be a mixture of an inorganic compound and an organic compound.

[0010] There are no particular limitations on the inorganic compounds, but examples include smectites such as bentonite, montmorillonite, bydelite, nontronite, saponite, hectorite, soconite, and stibnsite; vermiculites such as di-vermiculite and tri-vermiculite; kaolins such as halloysite, kaolinite, endelite, dickite, nacrite, and chrysotile; phyllosilicates such as talc, pyrophyllite, mica, margalite, clintonite, muscovite, biotite, phlogopite, synthetic mica, fluorite, paragolite, phlogopite, lepidolite, tetrasilicic mica, and teniolite; and Examples include jamonite such as nchigolite; chlorite such as donpasite, sudite, kukkaite, clinochlore, chamosite, chlorite, and nanthite; pyolite-paligoskite such as sepiolite and palygorskite; carbonates such as calcium carbonate, magnesium carbonate, and barium carbonate; sulfates such as calcium sulfate and barium sulfate; metal oxides such as silica, alumina, magnesium oxide, antimony trioxide, titanium oxide, white carbon, and iron oxide; metal hydroxides such as aluminum hydroxide, magnesium hydroxide, and iron hydroxide; red iron oxide; carbon black; graphite, etc., and may consist of one or more of these.

[0011] There are no particular limitations on the organic compounds, but examples include fatty acid metal salts, waxes, organic polymers, etc., and the mixture may consist of one or more of these compounds. There are no particular limitations on fatty acid metal salts, but examples include magnesium laurate, calcium laurate, zinc laurate, magnesium myristate, calcium myristate, zinc myristate, magnesium palmitate, calcium palmitate, zinc palmitate, magnesium stearate, calcium stearate, zinc stearate, aluminum trioctadecanoate, aluminum dioctadecanoate, aluminum monooctadecanoate, calcium octadecanoate, zinc octadecanoate, magnesium octadecanoate, and barium octadecanoate. There are no particular limitations on the waxes used, but examples include paraffin wax, microcrystalline wax, candelilla wax, carnauba wax, rice wax, Fischer-Tropsch wax, Montan wax, beeswax, lauric acid amide, stearic acid amide, oleic acid amide, ethylenebisstearic acid amide, hydrogenated castor oil, and 12-hydroxystearic acid.

[0012] There are no particular limitations on the organic polymers, but examples include olefin polymers such as polyethylene, polypropylene, ethylene-α-olefin copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-(meth)acrylate copolymer, modified polyethylene, and modified polypropylene; acrylic polymers such as poly(meth)acrylate methyl, poly(meth)acrylate ethyl, poly(meth)acrylate butyl, and modified acrylic resins (e.g., silicone-modified acrylic resin, vinyl chloride-modified acrylic resin, acrylic-urethane resin, etc.); polycarbonate; fluorine polymers such as ethylene-tetrafluoroethylene and polyvinylidene fluoride; polystyrene, chloropolystyrene, poly-α-methylstyrene, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, and styrene-(meth)acrylic acid ester copolymer (e.g., styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene Examples include styrene-based polymers such as butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-phenyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-phenyl methacrylate copolymer, etc., styrene-methyl α-chloroacrylate copolymer, styrene-acrylonitrile-acrylic acid ester copolymer, and acrylonitrile-styrene-butadiene copolymer (ABS); chlorine-based polymers such as polyvinyl chloride and polyvinylidene chloride; rosin-modified maleic acid resins; polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polylactic acid (PLA); polyamides such as nylon 6 and nylon 66; phenolic resins; epoxy resins; polydienes such as polybutadiene, polyisoprene, and polychloroprene; ionomer resins; polyurethane resins; silicone resins; ketone resins; xylene resins; polyvinyl butyral resins; and modified polyphenylene oxide resins.

[0013] The fine particles (A) are not particularly limited, but it is preferable that they be at least one selected from inorganic fine particles, fatty acid metal salts, waxes, and organic polymer fine particles, as this improves adhesion resistance. While there are no particular limitations on the inorganic fine particles, it is preferable that they include at least one selected from kaolin, phyllosilicate, and carbonate, as this improves their disintegration properties. While there are no particular limitations on the organic fine particles, it is preferable that they include at least one selected from metal stearate, stearamide, and polyethylene particles, as this improves their disintegration properties.

[0014] Furthermore, the fine particles (A) may contain crystalline silica. There are no particular limitations on the crystalline silica, but examples include quartz, cristobalite, tridymite, coesite, and stishobalite. The weight percentage of crystalline silica in the fine particles (A) is not particularly limited, but is preferably 20% by weight or less, more preferably 10% by weight or less, and most preferably 5% by weight or less. When the weight percentage is 20% by weight or less, dispersibility and anti-adhesion properties tend to improve.

[0015] The average particle size of the fine particles (A) is not particularly limited, but is preferably 0.1 to 200 μm, more preferably 0.1 to 100 μm, even more preferably 0.1 to 50 μm, particularly preferably 0.1 to 40 μm, and most preferably 0.1 to 30 μm. When the average particle size is within the above range, adhesion to unvulcanized rubber tends to improve. The average particle size of the fine particles (A) in this invention was measured using a dry measurement method with a laser diffraction particle size distribution analyzer (Mastersizer 3000, manufactured by Malvern). The average particle size was determined using the D50 value obtained by volume-based measurement.

[0016] [Surfactants (B)] The anti-adhesion composition of the present invention contains a surfactant (B). Surfactant (B) is a component that imparts wettability and adhesion to unvulcanized rubber. Furthermore, surfactant (B) must contain a nonionic surfactant (B1) containing nitrogen atoms (hereinafter sometimes referred to as surfactant (B1)), and the weight percentage of surfactant (B1) in surfactant (B) is more than 10% by weight. With such surfactant (B), the wettability and adhesion of the aqueous dispersion of the anti-adhesion agent composition to rubber are improved, so anti-adhesion treatment can be efficiently performed with a low-concentration aqueous dispersion.

[0017] The surfactant (B1) is not particularly limited, but it is preferable if it has a hydrocarbon group with 7 to 24 carbon atoms in its molecule, as this improves its wettability and adhesion to rubber. The number of carbon atoms is more preferably 8 to 22, even more preferably 10 to 20, and particularly preferably 10 to 18. The hydrocarbon group may be linear or branched. Furthermore, the hydrocarbon group may have a cyclic structure such as an aromatic ring or an alicyclic structure. The hydrocarbon group may be saturated or unsaturated.

[0018] The surfactant (B1) is not particularly limited, but it is preferable if it has an oxyalkylene group with 2 to 4 carbon atoms, as this improves wettability and adhesion to rubber. The number of carbon atoms is more preferably 2 to 3. When the surfactant (B1) has oxyalkylene groups, there are no particular limitations, but it is preferable that it has an average of 1 to 20 oxyalkylene groups, more preferably 1 to 15, even more preferably 1 to 10, and most preferably 1 to 5. When the average number of oxyalkylene groups in the surfactant (B1) is within the above range, the adhesion to rubber tends to improve.

[0019] The surfactant (B1) is not particularly limited, but it is preferable that it be at least one selected from the compound represented by the following general formula (1) (B1-1) and the compound represented by the following general formula (2) (B1-2) in order to improve wettability and adhesion to rubber.

[0020] [ka] (In the formula, R 1is a monovalent hydrocarbon group having 7 to 24 carbon atoms, and R 2 and R 3 are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. AO is an oxyalkylene group having 2 to 4 carbon atoms. m and n each represent the average number of moles of addition of AO, and m + n = 1 to 20.)

[0021] [Chemical Formula] (In the formula, R 4 is a monovalent hydrocarbon group having 7 to 24 carbon atoms, and R 5 and R 6 are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. AO is an oxyalkylene group having 2 to 4 carbon atoms. p and q each represent the average number of moles of addition of AO, and p + q = 1 to 20.)

[0022] In general formula (1), the hydrocarbon group of R 1 is preferably the same as the hydrocarbon group (hydrocarbon group having 7 to 24 carbon atoms) that the above-described surfactant (B1) has in its molecule. In general formula (2), the hydrocarbon group of R 4 is preferably the same as the hydrocarbon group (hydrocarbon group having 7 to 24 carbon atoms) that the above-described surfactant (B1) has in its molecule.

[0023] In general formula (1), AO is preferably the same as the oxyalkylene group (oxyalkylene group having 2 to 4 carbon atoms) that the above-described surfactant (B1) has in its molecule.<0—000163>In general formula (2), AO is preferably the same as the oxyalkylene group (oxyalkylene group having 2 to 4 carbon atoms) that the above-described surfactant (B1) has in its molecule.

[0024] In general formula (1), m and n are 0 or more. In general formula (1), m + n is preferably the same as the average number (1 to 20) of oxyalkylene groups that the above-described surfactant (B) has in its molecule. In general formula (2), p and q are greater than or equal to 0. In general formula (2), p+q is preferably the same as the average number (1 to 20) of oxyalkylene groups contained in the molecule of the surfactant (B) described above.

[0025] In general formula (1), R 2 and R 3 While there are no particular limitations, in terms of achieving the effects of the present invention, it is more preferable that each be independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, even more preferably that each be independently a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms, and particularly preferably a hydrogen atom. The hydrocarbon group may be linear or branched. Furthermore, the hydrocarbon group may have a cyclic structure such as an aromatic ring or an alicyclic structure. The hydrocarbon group may be saturated or unsaturated.

[0026] In general formula (2), R 5 and R 6 While there are no particular limitations, in terms of achieving the effects of the present invention, it is more preferable that each be independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, even more preferably that each be independently a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms, and particularly preferably a hydrogen atom. The hydrocarbon group may be linear or branched. Furthermore, the hydrocarbon group may have a cyclic structure such as an aromatic ring or an alicyclic structure. The hydrocarbon group may be saturated or unsaturated.

[0027] There are no particular limitations on the surfactant (B1), but examples include polyoxyalkylene alkylamines such as polyoxyethylene octylamino ether, polyoxyethylene laurylamino ether, polyoxyethylene cetylamino ether, polyoxyethylene stearylamino ether, polyoxyethylene oleylamino ether, polyoxyethylene linoleylamino ether, polyoxypropylene octylamino ether, polyoxypropylene laurylamino ether, polyoxypropylene cetylamino ether, polyoxypropylene stearylamino ether, polyoxypropylene oleylamino ether, polyoxypropylene linoleylamino ether; polyoxyethylene octyl acid monoethanolamide, polyoxyethylene lauric acid monoethanolamide, polyoxyethylene cetyryl acid monoethanolamide, polyoxy Examples of polyoxyalkylene fatty acid amides include polyethylene stearate monoethanolamide, polyoxyethylene oleate monoethanolamide, polyoxyethylene linolenic acid monoethanolamide, polyoxypropylene octyl acid monoethanolamide, polyoxypropylene laurate monoethanolamide, polyoxypropylene cetiryl acid monoethanolamide, polyoxypropylene stearate monoethanolamide, polyoxypropylene oleate monoethanolamide, polyoxypropylene linolenic acid monoethanolamide, octyl acid monomethylethanolamide, laurate monomethylethanolamide, cetiryl acid monomethylethanolamide, stearate monomethylethanolamide, oleate monomethylethanolamide, linolenic acid monomethylethanolamide, etc., and one or more of these may be used in combination.

[0028] As described above, the weight percentage of surfactant (B1) in surfactant (B) is greater than 10% by weight. If the weight percentage is 10% by weight or less, the adhesion to rubber decreases. The weight percentage is preferably 12.5 to 100% by weight, more preferably 15 to 95% by weight, even more preferably 17.5 to 90% by weight, and particularly preferably 20 to 85% by weight.

[0029] Surfactant (B) may further contain surfactant (B2) other than surfactant (B1) (hereinafter sometimes referred to as surfactant (B2)). There are no particular limitations on the surfactant (B2), but examples include nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants that do not contain nitrogen atoms, and one or more types may be used in combination.

[0030] Nonionic surfactants that do not contain nitrogen atoms are not particularly limited, but examples include polyoxyalkylene alkyl ethers such as polyoxyethylene cetyl ether and polyoxyethylene lauryl ether; polyoxyalkylene alkylphenyl ethers such as polyoxyethylene nonylphenyl ether and polyoxyethylene octylphenyl ether; polyoxyalkylene fatty acid esters such as polyoxyethylene monolaurate and polyoxyethylene monooleate; polyoxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate; polyoxyalkylene hydrogenated castor oil; polyoxyalkylene sorbitol fatty acid esters; polyglycerin fatty acid esters; alkylglycerin ethers; polyoxyalkylene cholesteryl ethers; alkyl polyglucosides; and sucrose fatty acid esters.

[0031] There are no particular limitations on the anionic surfactants, but examples include: higher fatty acid salts such as sodium coconut fatty acid, sodium stearate, and potassium stearate; alkyl sulfate esters such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium stearyl sulfate, and sodium cetyl sulfate; polyoxyalkylene alkyl ether acetates such as sodium polyoxyethylene tridecyl ether acetate; alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate; polyoxyalkylene alkyl ether sulfates; long-chain sulfosuccinates such as sodium 2-ethylhexyl sulfosuccinate; sodium oleoyl sarcosinate, lauryl sulfate. Examples include N-acyl sarcosinate salts such as sodium loyl sarcosinate; higher fatty acid amide sulfonates such as sodium stearoyl methyl taurate, sodium lauroyl methyl taurate, sodium myristoyl methyl taurate, and sodium palmitoyl methyl taurate; alkyl phosphates such as sodium monostearyl phosphate; polyoxyalkylene alkyl ether phosphate salts such as sodium polyoxyethylene oleyl ether phosphate and sodium polyoxyethylene stearyl ether phosphate; and long-chain N-acyl glutamate salts such as sodium N-lauroyl glutamate monosodium and disodium N-stearoyl-L-glutamate.

[0032] There are no particular limitations on cationic surfactants, but examples include alkyltrimethylammonium salts such as stearyltrimethylammonium chloride, lauryltrimethylammonium chloride, and cetyltrimethylammonium bromide; dialkyldimethylammonium salts; trialkylmethylammonium salts; and alkylamine salts. There are no particular limitations on amphoteric surfactants, but examples include imidazoline-based amphoteric surfactants such as 2-undecyl-N,N-(hydroxyethylcarboxymethyl)-2-imidazoline sodium and 2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt; betaine-based amphoteric surfactants such as 2-heptadecyl-N-carboxymethyl-N-hydroxyethylimidazolium betaine, lauryldimethylaminoacetic acid betaine, and coconut oil fatty acid amidopropyl betaine; and amino acid-type amphoteric surfactants such as N-laurylglycine, N-lauryl β-alanine, and N-stearyl β-alanine.

[0033] Surfactant (B) is preferable if it further contains an anionic surfactant as surfactant (B2) in that it improves wettability and adhesion. If surfactant (B) further contains an anionic surfactant, the weight percentage of the anionic surfactant in surfactant (B) is not particularly limited, but is preferably 5 to 70% by weight, more preferably 10 to 60% by weight, and even more preferably 15 to 50% by weight. When the weight percentage is 5% by weight or more, wettability tends to improve. When the weight percentage is 70% by weight or less, adhesion tends to improve.

[0034] [Water-soluble polymer (C)] The anti-adhesion composition of the present invention may contain a water-soluble polymer (C). The inclusion of a water-soluble polymer (C) in the anti-adhesion composition imparts viscosity to the aqueous dispersion of the anti-adhesion composition, improving its adhesion to the unvulcanized rubber surface, which is preferable. The water-soluble polymer (C) is excluding the surfactant (B) mentioned above. In this invention, water solubility means that the solubility in water at 20°C is 1 g / 100 g or more.

[0035] The water-soluble polymer (C) is not particularly limited, but examples include starches such as oxidized starch, acetic acid starch, phosphate starch, carboxymethyl starch, carboxyethyl starch, hydroxyethyl starch, positive starch, cyanoethylated starch, and dialdehyde starch; mannan; alginic acid derivatives such as alginic acid, sodium alginate, propylene glycol alginate, triethanolamine alginate, and ammonium alginate; methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, and hydroxypropylcellulose. Examples include cellulose ethers such as ethylmethylcellulose, hydroxyethylcellulose, and carboxymethylcellulose; natural gums such as tarakanto gum, gum arabic, guar gum, xanthan gum, British gum, glucomannan, gellan gum, tara gum, locust bean gum, and carrageenan; sodium polyacrylate; polyvinyl alcohol; polyethylene glycol; polyethylene oxide; water-soluble acrylic resin; water-soluble urethane resin; water-soluble melamine resin; water-soluble epoxy resin; water-soluble butadiene resin; and water-soluble phenolic resin, and one or more of these may be used in combination.

[0036] The molecular weight of a water-soluble polymer (C) can usually be expressed as either a number-average molecular weight or a weight-average molecular weight. The ratio of the number-average molecular weight to the weight-average molecular weight is called the dispersion ratio, and the closer this ratio is to 1, the narrower the molecular weight distribution, indicating that it is close to monodisperse. However, there are no particular limitations on the molecular weight distribution of a water-soluble polymer (C); it may be monodisperse or polydisperse. The number-average molecular weight of the water-soluble polymer (C) is not particularly limited, but is preferably 5,000 to 1,000,000, more preferably 10,000 to 5,000,000, especially preferably 50,000 to 2,500,000, and most preferably 1,000,000 to 1,000,000. When the number-average molecular weight is 5,000 or more, the strength of the formed film tends to improve and the anti-adhesion properties tend to improve. When the number-average molecular weight is 1,000,000 or less, the handling properties of the anti-adhesion composition for unvulcanized rubber tend to improve.

[0037] The anti-adhesion composition of the present invention may contain other components (hereinafter sometimes referred to as "other components") in addition to the fine particles (A), surfactant (B), and water-soluble polymer (C) described above. While there are no particular limitations on the other components, examples include polyhydric alcohols, defoamers, preservatives, and water.

[0038] [Polyhydric alcohols] Polyhydric alcohols adhere to the surface of unvulcanized rubber, providing lubrication between the rubber layers and reducing friction between them. There are no particular limitations on the polyhydric alcohols, but examples include glycerin, 1,3-butanediol, propylene glycol, dipropylene glycol, pentylene glycol, neopentyl glycol, hexylene glycol, polyethylene glycol, erythritol, pentaerythritol, dipentaerythritol, trimethylolethane, trimethylolpropane, ditrimethylolpropane, xylitol, sorbitol, mannitol, maltitol, maltotriose, glucose, sucrose, fructose, maltose, etc., and one or more of these may be used in combination.

[0039] [Antifoaming agent] There are no particular limitations on the defoaming agent, but examples include: silicone-based defoamers such as polymethylsiloxane and polyether-modified silicone; oil-based defoamers such as castor oil, sesame oil, linseed oil, and animal and vegetable oils; fatty acid-based defoamers such as stearic acid, oleic acid, and palmitic acid; fatty acid ester-based defoamers such as isoamyl stearate, distearyl succinate, ethylene glycol distearate, and butyl stearate; and polyoxyalkylene monohydrate alcohols such as di-t-amylphenoxyethanol, 3-heptanol, and 2-ethylhexanoyl. Examples of defoaming agents include alcohol-based defoamers such as ethanol; ether-based defoamers such as di-t-amylphenoxyethanol, 3-heptylcellosolve, nonylcellosolve, and 3-heptylcarbitol; phosphate ester defoamers such as tributylphosphate and tris(butoxyethyl)phosphate; amine-based defoamers such as diamylamine; amide-based defoamers such as polyalkyleneamide and acylate polyamine; sulfate ester defoamers such as sodium lauryl sulfate; polyoxyalkylene-based defoamers; and mineral oil. One or more of these may be used in combination.

[0040] [Preservatives] Examples of preservatives include thiazoles such as thiazole and 2-mercaptothiazole; thiocyanates such as methylene bisthiocyanate and ammonium thiocyanate; sulfimides such as o-benzoix sulfimide and phenylmercuric-o-benzoix sulfimide; alkyldialkylthiocarbamates such as methyldimethylthiocarbamate and ethyldiethyldithiocarbamate; thiraum sulfides such as tetramethylthiraum sulfide and tetraethylthiraum sulfide; thiraum disulfides such as tetramethylthiraum disulfide and tetraethylthiraum disulfide; dithiocarbamates such as ferric diethyldithiocarbamate and reed dimethyldithiocarbamate; sulfamides such as o-toluenesulfonamide and benzenesulfonanilide; and 1-aminonaphthyl-4-sulfonic acid, 1-amino Examples include aminosulfonic acids such as -2-naphthol-4-sulfonic acid; phenols such as pentachlorophenol and o-phenylphenol and their alkali metal salts; chloride quinones such as tetrachloro-p-benzoquinone and 2,3-dichloro-1,4-naphthoquinone; nitro group-containing compounds such as dinitrocaprylphenylcrotonate and dinitro-o-cresol; triazines such as 1,3,5-trihydroxyethylhexahydro-1,3,5-triazine and 1,3,5-triethylhexahydro-1,3,5-triazine; organic mercury compounds such as phenylmercuric phthalate and o-hydroxyphenylmercuric chloride; amines such as p-aminoazobenzene and diphenylamine; amides such as cinnamanilide; and iodine-containing compounds such as 1,3-diiodo-2-propanol. One or more of these may be used in combination.

[0041] [Anti-adhesion composition for unvulcanized rubber and method for producing the same] As described above, the anti-adhesion composition of the present invention contains the fine particles (A) and surfactant (B) described above, and exhibits excellent wettability, anti-adhesion properties, and disintegration properties.

[0042] The content of fine particles (A) is not particularly limited, but is preferably 20 to 90 parts by weight, more preferably 35 to 85 parts by weight, and even more preferably 50 to 80 parts by weight, per 100 parts by weight of the anti-adhesion composition. When the content is 20 parts by weight or more, the anti-adhesion properties tend to improve. When the content is 90 parts by weight or less, the wettability tends to improve.

[0043] The content of surfactant (B) is not particularly limited, but is preferably 0.1 to 28 parts by weight, more preferably 1 to 25 parts by weight, and even more preferably 5 to 20 parts by weight, per 100 parts by weight of the anti-adhesion composition. When the content is 0.1 parts by weight or more, wettability tends to improve. When it is 28 parts by weight or less, adhesion tends to improve.

[0044] The content of surfactant (B) is not particularly limited, but is preferably 1 to 30 parts by weight, more preferably 3 to 27 parts by weight, and even more preferably 5 to 25 parts by weight per 100 parts by weight of fine particles (A). When the content is 1 part by weight or more, wettability tends to improve. When the content is 30 parts by weight or less, adhesion tends to improve.

[0045] When the anti-adhesion composition of the present invention contains a water-soluble polymer (C), the content of the water-soluble polymer (C) is not particularly limited, but is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 15 parts by weight, and even more preferably 1 to 10 parts by weight, per 100 parts by weight of the anti-adhesion composition. When the content is 0.1 parts by weight or more, the anti-adhesion properties tend to improve. When the content is 20 parts by weight or less, the drying properties tend to improve.

[0046] When the anti-adhesion composition of the present invention contains a water-soluble polymer (C), the content of the water-soluble polymer (C) is not particularly limited, but is preferably 0.5 to 18 parts by weight, more preferably 1 to 15 parts by weight, and even more preferably 2 to 10 parts by weight per 100 parts by weight of fine particles (A). When the content is 0.5 parts by weight or more, the anti-adhesion properties tend to improve. When the content is 18 parts by weight or less, the drying properties tend to improve.

[0047] When the anti-adhesion agent composition of the present invention is in the form of an aqueous dispersion, the weight percentage of water in the anti-adhesion agent composition is not particularly limited, but is preferably 90 to 99.99% by weight, more preferably 92.5 to 99.95% by weight, and even more preferably 95 to 99.9% by weight. When the weight percentage is 90% by weight or more, drying properties tend to improve, and when it is 99.99% by weight or less, handling properties tend to improve. When the anti-adhesion agent composition is in the form of an aqueous dispersion, the water used can be tap water, deionized water, distilled water, etc., and is not particularly limited, but deionized water or distilled water is preferred. Furthermore, from the viewpoint of quality control, soft water is preferred because its hardness can be adjusted.

[0048] The present invention provides a method for producing an anti-adhesion composition, and there are no particular limitations on the mixing order or the mixing equipment used, as long as it includes a step of mixing fine particles (A) and a surfactant (B), and optionally a water-soluble polymer (C) or other components. The anti-adhesion composition is not particularly limited, but can be produced, for example, by sequentially adding and mixing each component in a mixer such as a ribbon mixer or a vertical screw mixer.

[0049] [Method for manufacturing unvulcanized rubber with anti-adhesion treatment] The present invention provides a method for producing anti-adhesion treated unvulcanized rubber, which includes a step of applying the above-described anti-adhesion composition to the surface of the unvulcanized rubber (hereinafter sometimes referred to as step (I)). Here, the unvulcanized rubber may be molded.

[0050] In step (I), a wet method is preferred, that is, a method using the anti-adhesion agent composition in the form of the aqueous dispersion described above, or a method using an aqueous dispersion in which the anti-adhesion agent composition is dispersed in water. The effective concentration of the aqueous dispersion is not particularly limited, but is preferably 0.01 to 10% by weight, more preferably 0.05 to 7.5% by weight, and even more preferably 0.1 to 5% by weight. When the effective concentration is 0.01% by weight or higher, the anti-adhesion properties tend to improve. When the effective concentration is 10% by weight or lower, the handling properties tend to improve.

[0051] When performing the processing steps using the wet method, methods include spraying the anti-adhesion agent composition in the form of an aqueous dispersion or an aqueous dispersion of the anti-adhesion agent composition in water, spraying it onto the rubber with a fine stream, or immersing it in the aqueous dispersion. The method of immersion in an aqueous dispersion is preferred because it allows for uniform application of the anti-adhesion composition for unvulcanized rubber.

[0052] The unvulcanized rubber used in the manufacturing method of the present invention is usually heated to 100-180°C and can be cooled by immersion in an aqueous dispersion. The temperature of the aqueous dispersion is not particularly limited, but is preferably 0-60°C. Next, a step may be taken to dry the unvulcanized rubber after applying the aqueous dispersion. There are no particular limitations on the drying method, but a method of forcibly drying by blowing hot air using a hot air fan or blow heater is preferable because it is inexpensive.

[0053] Furthermore, in step (I), a dry method may be used, that is, a method using an anti-adhesion composition that does not contain water. The anti-adhesion treated unvulcanized rubber produced by the method described above can prevent adhesion between pieces of unvulcanized rubber when stored in stacks until the next process begins. [Examples]

[0054] The present invention will be specifically described below with reference to examples and comparative examples. The present invention is not limited to these examples. In the following examples and comparative examples, unless otherwise specified, "parts" means "parts by weight". Furthermore, in the following, the anti-adhesion agent composition for unvulcanized rubber may be referred to as "anti-adhesion agent composition" for simplicity. Furthermore, the measurement and evaluation of each physical property in the following examples and comparative examples were carried out as follows.

[0055] [Wettability] An NR / BR rubber test piece (natural rubber / butadiene rubber, 0.5 cm thick × 5 cm long × 3 cm wide) heated to 100°C was immersed in an aqueous dispersion of the anti-adhesion agent composition (effective concentration 1% by weight) and immediately removed. The wettability of the anti-adhesion agent composition was then evaluated based on the wettability of the unvulcanized rubber surface according to the following evaluation criteria. The entire surface of the unvulcanized rubber is wet: Wettability is good (indicator is ○) Some areas of the unvulcanized rubber surface are repelled: Wettability is slightly poor (indicator is △) The entire surface of the unvulcanized rubber is repelling water: Wettability is poor (indicator is ×)

[0056] [Adhesion resistance] An NR / BR test piece (natural rubber / butadiene rubber, 0.5 cm thick x 5 cm long x 3 cm wide), heated to 100°C, was immersed in an aqueous dispersion of the anti-adhesion agent composition (effective concentration 1% by weight) and immediately removed. Two immersed rubber test pieces were prepared, air-dried, and then stacked. A load of 1000 kg / m² was applied. 2 The specimens were subjected to a load and left in a 40°C constant temperature chamber for 24 hours. After removing the specimens from the chamber, they were air-cooled to room temperature, and the peel resistance (N / cm) was measured using a tensile testing machine at a speed of 100 mm / min. A lower peel resistance indicates easier peeling and higher adhesion resistance. The evaluation criteria were as follows, with a peel resistance of 2 N / cm or less being considered acceptable. Peel resistance of 1 N / cm or less: Excellent adhesion (unvulcanized rubber can be easily separated from each other; the indicator is ◎) Peel resistance greater than 1 N / cm and less than or equal to 2 N / cm: Good adhesion resistance (unvulcanized rubber can be peeled apart without load; the indicator is ○) Peel resistance greater than 2 N / cm and less than or equal to 3 N / cm: Poor adhesion resistance (high load when separating unvulcanized rubbers, resulting in low adhesion resistance; index is △) Peel resistance exceeding 3 N / cm: Very poor adhesion (the rubbers adhere tightly to each other, making separation difficult. Adhesion resistance is very low; the indicator is ×)

[0057] [Collapse-like] An aqueous dispersion of the anti-adhesion agent composition (effective concentration 4% by weight) was concentrated to dryness, and a 10 mm square dried solid was prepared. The hardness of the obtained dried solid was measured using a durometer. A smaller value indicates greater crumbling and disintegration. The evaluation criteria were as follows, and a value of less than 70 was considered acceptable. A value of less than 60 indicates very good disintegration (the dried solidified material disintegrates easily; the indicator is ◎). Value between 60 and 70: Good disintegration properties (dried solidified material disintegrates, indicator is ○) A value between 70 and 80: Poor disintegration (dried solidified material is somewhat difficult to disintegrate; the indicator is △) Values ​​above 80 or unmeasurable: Very poor disintegration (dried solidified material is difficult to disintegrate; the indicator is ×)

[0058] (Example 1) A powdered anti-adhesion agent composition was obtained by uniformly mixing 30 parts bentonite, 30 parts kaolinite, 35 parts calcium carbonate, and 5 parts POE(2) octylamine. The wettability, anti-adhesion properties, and disintegration properties of the obtained anti-adhesion agent composition were evaluated using the method described above. As shown in Table 1, the wettability was good, the anti-adhesion properties were very good, and the disintegration properties were good.

[0059] (Examples 2-21, Comparative Examples 1-6) In Examples 2-21 and Comparative Examples 1-6, powdered anti-adhesion compositions were obtained and evaluated in the same manner as in Example 1, except that the raw materials and their proportions were changed as shown in Tables 1-2. The evaluation results are shown in Tables 1-2. The details of the raw materials listed in Tables 1 and 2 are as follows. In addition, in the raw materials listed in Tables 1 and 2 and below, POE refers to polyoxyethylene, and the number in parentheses following POE indicates the average number of moles of oxyethylene added. Bentonite: Average particle size 25 μm Kaolinite: Average particle size 1 μm Talc: Average particle size 8 μm Calcium carbonate: Average particle size 4 μm Zinc stearate: Average particle size 5 μm Calcium stearate: Average particle size 5 μm Ethylene bistearate: Average particle size 12 μm Polyethylene particles: Average particle size 20 μm CMC-Na1: Sodium carboxymethylcellulose, viscosity of a 1% by weight aqueous solution at 25°C: 2000-4000 mPa·s, degree of etherification: 0.8-1.0 CMC-Na2: Sodium carboxymethylcellulose, viscosity of a 1% by weight aqueous solution at 25°C is 150-250 mPa·s, degree of etherification is 1.3-1.6.

[0060] [Table 1]

[0061] [Table 2]

[0062] As can be seen from Tables 1-2, the anti-adhesion compositions of Examples 1-21 contain fine particles (A) and a surfactant (B) containing more than 10% by weight of a nonionic surfactant (B1) containing nitrogen atoms, thus solving the problem of the present invention. On the other hand, the present invention fails to solve the problem when the fine particles (A) of Comparative Example 6 are not included, and when the surfactant (B) containing more than 10% by weight of the nitrogen atom-containing nonionic surfactant (B1) of Comparative Examples 1 to 5 is not included.

Claims

1. An anti-adhesion composition for unvulcanized rubber comprising fine particles (A) and a surfactant (B), The surfactant (B) includes a nonionic surfactant (B1) containing a nitrogen atom, The weight ratio of surfactant (B1) to surfactant (B) is more than 10% by weight. Anti-adhesion composition for unvulcanized rubber.

2. The anti-adhesion composition for unvulcanized rubber according to claim 1, wherein the content of the surfactant (B) is 1 to 30 parts by weight per 100 parts by weight of the fine particles (A).

3. The anti-adhesion composition for unvulcanized rubber according to claim 1 or 2, wherein the fine particles (A) are at least one selected from inorganic fine particles, fatty acid metal salts, waxes, and organic polymer fine particles.

4. The anti-adhesion composition for unvulcanized rubber according to claim 1 or 2, wherein the surfactant (B1) has a hydrocarbon group having 7 to 24 carbon atoms in its molecule.

5. The anti-adhesion composition for unvulcanized rubber according to claim 1 or 2, wherein the surfactant (B1) has an oxyalkylene group having 2 to 4 carbon atoms, and the surfactant (B1) has an average of 1 to 20 of the oxyalkylene groups in its molecule.

6. The mold release agent composition according to claim 1 or 2, wherein the surfactant (B1) is at least one selected from the compound represented by the following general formula (1) (B1-1) and the compound represented by the following general formula (2) (B1-2). 【Chemistry 1】 (In the formula, R １ R is a monovalent hydrocarbon group having 7 to 24 carbon atoms. ２ and R ３ Each of these is independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms, AO is an oxyalkylene group having 2 to 4 carbon atoms, and m and n represent the average number of moles of AO added, with m + n = 1 to 20. 【Chemistry 2】 (In the formula, R ４ R is a monovalent hydrocarbon group having 7 to 24 carbon atoms. ５ and R ６ Each of these is independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms, AO is an oxyalkylene group having 2 to 4 carbon atoms, and p and q represent the average number of moles of AO added, with p + q = 1 to 20.

7. The anti-adhesion composition for unvulcanized rubber according to claim 1 or 2, further containing a water-soluble polymer (C).

8. A method for producing anti-adhesion treated unvulcanized rubber, comprising the step of applying the anti-adhesion composition for unvulcanized rubber described in claim 1 or 2 to the surface of unvulcanized rubber.

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