Release agent composition for molding and vulcanization of rubber products and its use

Abstract

To provide: a mold release agent composition for molding and vulcanization of a rubber product that has a good coating property and an excellent mold release property during a molding and vulcanization process of the rubber product, and that can be continuously molded and vulcanized; and a method for efficiently manufacturing a rubber product by using the mold release agent composition for molding and vulcanization.SOLUTION: There is provided a mold release agent composition for molding and vulcanization of a rubber product, comprising: an organosilicon compound (A); and a silicone component (B) excluding the organosilicon compound (A). The organosilicon compound (A) has at least one kind selected from a D unit represented by R1R2SiO2 / 2 and a T unit represented by R3SiO3 / 2, where the R1 to R3 are each independently a monovalent organic group, and the organosilicon compound (A) has a hydrolyzable group.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a mold release agent composition for molding and vulcanization of rubber products and its use. [Background technology]

[0002] In the process of molding and vulcanizing rubber products, a rubber bag called a bladder or airbag (hereinafter sometimes referred to as a bladder) is inserted inside the raw rubber product before molding and vulcanization. By introducing a high-temperature, high-pressure gas (for example, steam at approximately 180°C) or liquid into the bladder, the bladder is expanded, pressing the raw rubber against a mold, heating and pressurizing it, and thus manufacturing the rubber product through molding and vulcanization. When the rubber product is a tire, a bladder is inserted inside the tire before molding and vulcanization (hereinafter sometimes referred to as the green tire), the bladder is inflated, and the green tire is pressed into a mold and heated and pressurized to perform molding and vulcanization. In this case, since both the bladder and the inner surface of the green tire are made of rubber, a release agent is required between them.

[0003] Conventionally, in the molding and vulcanization of tires, methods have been used such as applying a water-based or solvent-based release agent, called inside paint, to the inner surface of the green tire each time, or applying a silicone-based release agent to the surface of the bladder to improve separation between the green tire and the bladder. Patent Document 1 proposes, for example, an aqueous diorganopolysiloxane emulsion in which an inorganic silicate whose surface has been hydrophobized by reaction with an organosilicon compound is dispersed as an inside paint. However, the method of applying the inside paint to the inner surface of the green tire each time is complicated and has the problem of causing contamination around the equipment during application. Furthermore, a bigger problem than this is that the inside paint can get into the joints of the tire inner liner, causing the inner liner joints to peel off and resulting in tire defects, and a huge amount of space is required as a stock point before the tires with the inside paint applied are put into the molding process.

[0004] Therefore, as an alternative to inside painting, there is a method of applying a silicone-based release agent to the bladder surface to improve the separation between the green tire and the bladder. As a release agent used in such a method, for example, Patent Document 2 proposes a method in which a vulcanizing bladder surface-treated with a release agent that is a silicone composition containing organopolysiloxane, methylhydrogenpolysiloxane, silica, and an organic salt of a metal is used. Furthermore, Patent Document 3 proposes a release agent composition that contains specific amounts of a specific reactive polysiloxane, a non-reactive polysiloxane exhibiting a specific HLB, and a surfactant, and exhibits a specific surface tension. However, in the method of applying a silicone-based release agent to the bladder surface, the adhesion to the bladder is insufficient, resulting in poor release properties during the molding and vulcanization process. In particular, when molding and vulcanization are performed continuously, the release film deteriorates in a short time, leading to defects in the rubber products being manufactured. Furthermore, in release agent compositions containing reactive polysiloxanes such as methylhydrogenpolysiloxane, there are problems with productivity, such as thickening and gelling due to the reaction progressing during storage.

[0005] Thus, each of the release agents in Patent Documents 1 to 3 has problems. However, at present, it is necessary to use conventional inside paint release agents and bladder release agent compositions despite having problems such as release property problems and workability problems.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] An object of the present invention is to provide a release agent composition for molding and vulcanizing rubber products that has good coating properties, excellent release properties during the molding and vulcanizing process of rubber products, and can be continuously molded and vulcanized, and a method for manufacturing rubber products that is efficiently performed using this release agent composition for molding and vulcanizing.

Means for Solving the Problems

[0008] As a result of intensive studies, the present inventor has found that the above problems can be solved by a release agent composition for molding and vulcanizing rubber products containing specific components, and has reached the present invention. That is, the present invention is a release agent composition for molding and vulcanizing rubber products containing an organosilicon compound (A) and a silicone component (B) excluding the organosilicon compound (A), wherein the organosilicon compound (A) has at least one selected from the D unit represented by R 1 R 2 SiO 2 / 2 and the T unit represented by R 3 SiO 3 / 2 and the R 1 ~R 3The present invention relates to a mold release agent composition for molding and vulcanizing rubber products, wherein each of the groups is independently a monovalent organic group, and the organosilicon compound (A) has a hydrolyzable group.

[0009] In the mold release agent composition for molding and vulcanizing rubber products of the present invention, it is preferable that the total molecular weight of the hydrolyzable groups relative to the molecular weight of the organosilicon compound (A) is 2 to 50%. The mold release agent composition for molding and vulcanizing rubber products of the present invention preferably contains 10 to 250 parts by weight of component (B) per 100 parts by weight of the organosilicon compound (A). The mold release agent composition for molding and vulcanization of rubber products of the present invention preferably further contains a surfactant (C). The mold release agent composition for molding and vulcanizing rubber products of the present invention preferably further contains a water-soluble polymer (D).

[0010] The present invention relates to a method for manufacturing a rubber product by molding and vulcanizing unvulcanized rubber, comprising: step 1, applying a mold release agent composition for molding and vulcanizing the rubber product to the rubber surface of a bladder and / or the surface of the unvulcanized rubber on the side that comes into contact with the bladder; and step 2, after step 1, heating and expanding the bladder contained in the unvulcanized rubber within a mold, thereby pressing the side of the unvulcanized rubber that does not come into contact with the bladder against the inner surface of the mold, and molding and vulcanizing the unvulcanized rubber. In the manufacturing method of the present invention, it is preferable that the rubber product is a tire. [Effects of the Invention]

[0011] The mold release agent composition for molding and vulcanizing rubber products of the present invention exhibits excellent coating properties, excellent release properties during the molding and vulcanization process of rubber products, and enables efficient continuous molding and vulcanization of rubber products. Furthermore, the mold release agent composition for molding and vulcanizing rubber products of the present invention exhibits excellent product stability. The present invention's method for manufacturing rubber products utilizes the above-mentioned mold release agent composition for molding and vulcanization of rubber products, thus enabling the efficient production of rubber products. [Modes for carrying out the invention]

[0012] The mold release agent composition for molding and vulcanizing rubber products of the present invention (hereinafter sometimes simply referred to as the mold release agent composition) essentially contains a specific organosilicon compound (A) and a silicone component (B) excluding the organosilicon compound (A). First, each component constituting the mold release agent composition for molding and vulcanizing rubber products will be described in detail.

[0013] 〔Organosilicon compound (A)〕 The mold release agent composition of the present invention contains a specific organosilicon compound (A) (hereinafter sometimes simply referred to as component (A)). Component (A) has at least one selected from the D unit represented by R 1 R 2 SiO 2 / 2 and the T unit represented by R 3 SiO 3 / 2 and further has a hydrolyzable group. Both the D unit and the T unit are siloxane units, and R 1 ~R 3 are each independently a monovalent organic group. In the mold release agent composition of the present invention, component (A) is a component that imparts film-forming properties and mold release properties. In the following, the "D unit represented by R 1 R 2 SiO 2 / 2 " may sometimes be simply referred to as the "D unit", and the "T unit represented by R 3 SiO 3 / 2 " may sometimes be simply referred to as the "T unit".

[0014] The hydrolyzable group possessed by component (A) becomes reactive by being hydrolyzed. Due to the reactivity of the hydrolyzable group after hydrolysis, mainly a dehydration condensation reaction occurs, and it is considered that film formation occurs through component (A) and mold release properties are imparted. Also, it is preferable that component (A) is a component having curability, as it can increase the strength of the formed film.

[0015] Examples of hydrolyzable groups in component (A) include isoalkoxy groups such as methoxy, ethoxy, propoxy, and butoxy groups; alkoxy-substituted alkoxy groups such as methoxyethoxy, ethoxyethoxy, and methoxypropoxy groups; acyloxy groups such as acetoxy, octanoyloxy, and benzoyloxy groups; alkenyloxy groups such as vinyloxy, propenyloxy, isopropenyloxy, isobutenyloxy, and cyclohexenyloxy groups; and dimethylketooxy groups. Examples of hydrolyzable groups include ketoxime groups such as methyl ethyl ketoxime group and diethyl ketoxime group; amino groups having hydrocarbon groups such as N-methylamino group, N,N-dimethylamino group, N,N-diethylamino group, N-butylamino group and cyclohexylamino group; aminooxy groups such as N,N-dimethylaminooxy group and N,N-diethylaminooxy group; and amide groups having hydrocarbon groups such as N-methylacetamide group, N-ethylacetamide group and N-methylbenzamide group. The hydrolyzable group of component (A) may be one of the above hydrolyzable groups or two or more. It is preferable that the hydrolyzable group is at least one selected from an alkoxy group, an alkoxy-substituted alkoxy group, an acyloxy group, an alkenyloxy group, a ketoxime group, and an amide group having a hydrocarbon group, as this allows for efficient film formation.

[0016] Component (A) has at least one constituent unit selected from D units and T units. Furthermore, the R possessed by D units and T units 1 ~R 3 Each of these is an independent monovalent organic group. R 1 ~R 3 While there are no particular limitations, in terms of achieving the effects of the present invention, it is preferable that the organic group has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and even more preferably 1 to 8 carbon atoms in a monovalent organic group. 1 ~R 3 The number of carbon atoms in the organic group is also R 1 ~R 3 It would be best for each to be independent.

[0017] R in D units 1 ~R 2 and R in T units 3 While there are no particular limitations, it is preferable that each of them be an unsubstituted monovalent hydrocarbon group, a substituted monovalent hydrocarbon group, or a hydrolyzable group, independently of the others. Examples of unsubstituted monovalent hydrocarbon groups include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, and decyl groups; cycloalkyl groups such as cyclopentyl and cyclohexyl groups; alkenyl groups such as vinyl, allyl, isopropenyl, 1-butenyl, and 2-butenyl groups; aryl groups such as phenyl, vinylphenyl, tolyl, xylyl, and naphthyl groups; and aralkyl groups such as benzyl, phenethyl, and phenylpropyl groups. Furthermore, a substituted monovalent hydrocarbon group can be defined as one having a group (substituent) in which some or all of the hydrogen atoms bonded to the carbon atom of the monovalent hydrocarbon group are substituted with other atoms or groups. Examples of such substituents include halogen atoms such as chlorine, fluorine, and bromine atoms, hydroxyl groups, amino groups, vinyl groups, epoxy groups, glycidyloxy groups, mercapto groups, acryloyloxy groups, methacryloyloxy groups, carboxyl groups, cyano groups, and isocyanate groups.

[0018] The ratio of the total number of D units and T units to the total number of units constituting component (A) is not particularly limited, but is preferably 10-100%, more preferably 20-100%, even more preferably 30-100%, and most preferably 40-100%. When this ratio is 10% or more, the flexibility and strength of the resulting film tend to improve. Furthermore, while component (A) is not particularly limited, it is preferable that it must contain T units, as this improves the strength of the resulting film. The ratio of the total number of T units to the total number of units constituting component (A) is not particularly limited, but is preferably 10-100%, more preferably 20-100%, even more preferably 30-100%, and most preferably 40-100%.

[0019] The molecular weight of component (A) is not particularly limited, but is preferably 200 to 50000. When the molecular weight is within this range, film-forming properties tend to improve. The upper limit of the molecular weight is more preferably 25000, even more preferably 15000, particularly preferably 12500, and most preferably 10000. Note that the molecular weight of component (A) is the weight-average molecular weight, which means the weight-average molecular weight in terms of polystyrene measured by gel permeation chromatography. Examples of component (A) include silicone resin and silicone oligomer. Component (A) is not particularly limited, but it is preferable that it includes a silicone oligomer.

[0020] The ratio of the total molecular weight of hydrolyzable groups to the molecular weight of component (A) (the total molecular weight of all hydrolyzable groups in component (A)) is not particularly limited, but is preferably 2 to 50%. When this ratio is 2% or more, film-forming properties tend to improve, and when it is 50% or less, the strength of the resulting film tends to improve. The upper limit of this ratio is more preferably 45%, even more preferably 40%, and particularly preferably 35%. On the other hand, the lower limit of this ratio is more preferably 3%, even more preferably 4%, and particularly preferably 5%.

[0021] [Silicone components (B) excluding organosilicon compounds (A)] The mold release agent composition of the present invention contains a silicone component (B) (hereinafter sometimes simply referred to as component (B)) excluding the organosilicon compound (A). In the mold release agent composition of the present invention, component (B) is a component that imparts lubricity. Component (B) is at least one selected from silicone oil, silicone rubber, silicone oligomer, and silicone resin. Examples of component (B) include dialkylpolysiloxanes such as dimethylpolysiloxane, diethylpolysiloxane, methylisopropylpolysiloxane, and methyldodecylpolysiloxane; alkylphenylpolysiloxanes such as methylphenylpolysiloxane, dimethylsiloxane-methylphenylsiloxane copolymer, and dimethylsiloxane-diphenylsiloxane copolymer; alkylaralkylpolysiloxanes such as methyl(phenylethyl)polysiloxane and methyl(phenylpropyl)polysiloxane; and 3,3,3-trifluoropropylmethylpolysiloxane, and one or more of these may be used in combination. Component (B) may be used as an emulsion in the manufacture of the mold release agent composition. When using an emulsion as component (B), the content of the surfactant contained in the emulsion shall be included in the content of surfactant (C) described later.

[0022] Component (B) is not particularly limited, but it is preferable that it is fluid at room temperature in order to provide lubrication and slipperiness between the unvulcanized rubber and the bladder. The viscosity of component (B) at 25°C is not particularly limited, but is preferably 100 to 200,000 mPa·s. When the viscosity is within this range, the coating properties and lubricity tend to improve. The upper limit of the viscosity is more preferably 100,000 mPa·s, and even more preferably 50,000 mPa·s. On the other hand, the lower limit of the viscosity is more preferably 300 mPa·s, even more preferably 500 mPa·s, and particularly preferably 1,000 mPa·s.

[0023] The content of component (B) is not particularly limited, but is preferably 10 to 250 parts by weight per 100 parts by weight of component (A). When the content is 10 parts by weight or more, the lubricity tends to improve, and when it is 250 parts by weight or less, the release properties tend to improve. The upper limit of the content is more preferably 225 parts by weight, and even more preferably 200 parts by weight. On the other hand, the lower limit of the content is more preferably 15 parts by weight, and even more preferably 20 parts by weight.

[0024] [Surfactants (C)] The mold release agent composition of the present invention is not particularly limited, but may further contain a surfactant (C) (hereinafter sometimes simply referred to as component (C)). Including component (C) is preferable because it improves the wettability of the mold release agent composition to the unvulcanized rubber and / or the rubber on the bladder surface, allowing the mold release agent composition to adhere more uniformly to the unvulcanized rubber and / or the rubber on the bladder surface. Here, "wetting" in interfacial chemistry refers to the phenomenon of replacing one fluid on the surface of a solid or liquid with another liquid. For example, when a solid / gas interface is replaced with a solid / liquid interface, the solid can be said to have been wetted with the liquid. Therefore, when it is said that the release agent composition of the present invention has wetted the unvulcanized rubber and / or the rubber on the bladder surface, it means that the interface between the unvulcanized rubber and / or the rubber on the bladder surface and the air has been sufficiently replaced with the interface between the unvulcanized rubber and / or the rubber on the bladder surface and the release agent composition.

[0025] Component (C) may include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, etc., and may contain one or more of these surfactants. Component (C) is not particularly limited, but it is preferable that it be at least one selected from nonionic surfactants and anionic surfactants, as this improves the wettability of the unvulcanized rubber and / or the bladder surface to the rubber.

[0026] Examples of nonionic surfactants include polyoxyalkylene alkyl ethers such as polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, and polyoxyethylene polyoxypropylene 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; sorbitan fatty acid esters such as sorbitan monopalmitate and sorbitan monooleate; polyoxyethylene sorbitan monostearate, polyoxy Examples include polyoxyalkylene sorbitan fatty acid esters such as ethylene sorbitan monooleate; glycerin fatty acid esters such as glycerin monostearate, glycerin monopalmitate, and glycerin monolaurate; polyoxyalkylene castor oil; polyoxyalkylene hydrogenated castor oil; polyoxyalkylene sorbitol fatty acid esters; polyglycerin fatty acid esters; alkylglycerin ethers; polyoxyalkylene cholesteryl ethers; alkyl polyglucosides; sucrose fatty acid esters; polyoxyalkylene alkylamines; and oxyethylene-oxypropylene block polymers, and one or more of these may be used in combination. The nonionic surfactant is not particularly limited, but it is preferable to include at least one selected from polyoxyalkylene alkyl ethers and polyoxyalkylene alkylphenyl ethers, as this improves the wettability to the unvulcanized rubber and / or the rubber on the bladder surface.

[0027] Examples of anionic surfactants include fatty acid salts such as sodium oleate, potassium palmitate, and triethanolamine oleate; 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; and sodium stearoyl methyl taurate, sodium lauroyl methyl taurate, sodium myristoyl methyl taurate, and sodium palmitoyl methyl taurate. Examples include higher fatty acid amide sulfonates; N-acyl sarcosinate salts such as sodium lauroyl sarcosinate; 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; long-chain sulfosuccinates such as sodium di-2-ethylhexyl sulfosuccinate and sodium dioctyl sulfosuccinate; long-chain N-acyl glutamate salts such as sodium N-lauroyl glutamate monosodium and disodium N-stearoyl-L-glutamate; and one or more of these may be used in combination. The anionic surfactant is not particularly limited, but it is preferable to include at least one selected from fatty acid salts, alkyl sulfate salts, alkylbenzene sulfonates, polyoxyalkylene alkyl ether sulfates, higher fatty acid amide sulfonates, polyoxyalkylene alkyl ether phosphate salts, and long-chain sulfosuccinates, as this improves wettability to unvulcanized rubber and / or rubber on the bladder surface.

[0028] Examples of cationic surfactants include alkyltrimethylammonium salts such as stearyltrimethylammonium chloride, lauryltrimethylammonium chloride, and cetyltrimethylammonium bromide; dialkyldimethylammonium salts; trialkylmethylammonium salts; and alkylamine salts. One or more of these may be used in combination. Examples of amphoteric surfactants 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, amidopropyl betaine, alkyl betaine, amidobetaine, and sulfobetaine; and amino acid-type amphoteric surfactants such as N-laurylglycine, N-lauryl β-alanine, and N-stearyl β-alanine. One or more of these may be used in combination.

[0029] When the mold release agent composition of the present invention contains component (C), its content is not particularly limited, but is preferably 5 to 50 parts by weight per 100 parts by weight of component (A). When the content is 5 parts by weight or more, the wettability to the unvulcanized rubber and / or the rubber on the bladder surface tends to improve, and when it is 50 parts by weight or less, foaming tends to be suppressed. The upper limit of the content is more preferably 49 parts by weight, even more preferably 48 parts by weight, and particularly preferably 47 parts by weight. On the other hand, the lower limit of the content is more preferably 6 parts by weight, even more preferably 7 parts by weight, and particularly preferably 8 parts by weight.

[0030] [Water-soluble polymer (D)] The release agent composition of the present invention may further contain a water-soluble polymer (D) (hereinafter sometimes simply referred to as component (D)). Further inclusion of component (D) is preferable in that it improves the adhesion of the release agent composition. Component (D) includes, for example, 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 compounds such as alginic acid, sodium alginate, propylene glycol alginate, triethanolamine alginate, and ammonium alginate; methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, and hydroxyethylmethylcellulose. Examples include cellulose ethers such as hydroxyethyl ethylcellulose, carboxymethylcellulose and its salts; 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; water-soluble phenol resin, etc., and one or more of these components (D) may be used in combination. Component (D) is not particularly limited, but preferably contains at least one selected from carboxymethylcellulose and its salts, guar gum, and xanthan gum.

[0031] When the mold release agent composition of the present invention contains component (D), its content is not particularly limited, but is preferably 0.1 to 25 parts by weight per 100 parts by weight of component (A). When the content of component (D) is 0.1 parts by weight or more, the adhesion of the mold release agent composition tends to improve, and when it is 25 parts by weight or less, the handling properties of the mold release agent composition tend to improve. The upper limit of the content is more preferably 20 parts by weight, even more preferably 15 parts by weight, and particularly preferably 10 parts by weight. On the other hand, the lower limit of the content is more preferably 0.2 parts by weight, even more preferably 0.3 parts by weight, and particularly preferably 0.4 parts by weight.

[0032] [Other ingredients] In addition to the components described above, the mold release agent composition of the present invention may further contain inorganic powders, metal soaps, waxes, polymer particles, defoamers, preservatives, catalysts, and the like.

[0033] Examples of inorganic powders include carbonates such as calcium carbonate, magnesium carbonate, and barium carbonate; silicates such as kaolin, aluminum silicate, calcium silicate, clay, talc, mica, sericite, and bentonite; sulfates such as calcium sulfate and barium sulfate; metal oxides such as silica, alumina, magnesium oxide, antimony trioxide, titanium dioxide, white carbon, and iron oxide; metal hydroxides such as aluminum hydroxide, magnesium hydroxide, and iron hydroxide; red iron oxide; carbon black; graphite, etc., and one or more of these may be used in combination.

[0034] Examples of metal soaps 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. One or more of these may be used in combination.

[0035] Examples of waxes include plant-based waxes, animal-based waxes, mineral waxes, petroleum waxes, synthetic hydrocarbon waxes, modified waxes, hydrogenated waxes, fatty acid amides, phthalic acid imides, etc., and one or more types may be used in combination. Examples of plant-based waxes include candelilla wax, carnauba wax, rice wax, wood wax, jojoba oil, sugar wax, bayberry wax, ocury wax, and esparto wax, and one or more types may be used in combination. Examples of animal-derived waxes include beeswax, lanolin, whale wax, insect wax, and shellac wax, and one or more types may be used in combination. Examples of mineral-based waxes include montan wax, ozokerite, and ceresin, and one or more types may be used in combination.

[0036] Examples of petroleum waxes include paraffin wax, microcrystalline wax, and petrolactam, and one or more types may be used in combination. Examples of synthetic hydrocarbon waxes include Fischer-Tropsch wax and polyethylene wax, and one or more types may be used in combination. Examples of modified waxes include montan wax derivatives, paraffin wax derivatives, and microcrystalline wax derivatives, and one or more of these may be used in combination. Examples of hydrogenated waxes include hydrogenated castor oil, 12-hydroxystearic acid, 12-hydroxystearic acid amide, N-hydroxyethyl-12-hydroxystearylamide, N,N'-ethylene-bis-12-hydroxystearylamide, N,N'-hexamethylene-bis-12-hydroxystearylamide, N,N'-xylylene-bis-12-hydroxystearylamide, methyl-12-hydroxystearate, propylene glycol-mono-12-hydroxystearate, ethylene glycol-mono-12-hydroxystearate, etc., and one or more of these may be used in combination.

[0037] Examples of polymer particles include particles made of polystyrene, polyacrylonitrile, polymethacrylonitrile, polymethyl (meth)acrylate, and one or more of these may be used in combination. Examples of defoaming agents include: oil-based defoaming agents such as castor oil, sesame oil, linseed oil, and animal and vegetable oils; fatty acid-based defoaming agents such as stearic acid, oleic acid, and palmitic acid; fatty acid ester-based defoaming agents such as isoamyl stearate, distearyl succinate, ethylene glycol distearate, and butyl stearate; alcohol-based defoaming agents such as polyoxyalkylene monohydrate, di-t-amyl phenoxyethanol, 3-heptanol, and 2-ethylhexanol; and di-t-amyl phenoxyethanol. Examples of antifoaming agents include ether-based antifoaming agents such as phenoxyethanol, 3-heptylcellosolve, nonylcellosolve, and 3-heptylcarbitol; phosphate ester-based antifoaming agents such as tributyl phosphate and tris(butoxyethyl) phosphate; amine-based antifoaming agents such as diamylamine; amide-based antifoaming agents such as polyalkyleneamide and acylate polyamine; sulfate ester-based antifoaming agents such as sodium lauryl sulfate; paraffinic mineral oil; naphthenic mineral oil, etc., and one or more of these may be used in combination.

[0038] Examples of preservatives include thiazoles such as thiazole and 2-mercaptothiazole; thiocyanates such as methylene bisthiocyanate and ammonium thiocyanate; sulfimides such as o-benzoic sulfimide and phenylmercuric-o-benzoic 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; 1 Examples include aminosulfonic acids such as -aminonaphthyl-4-sulfonic acid and 1-amino-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; organic mercury compounds such as phenylmercuric phthalate and o-hydroxyphenylmercuric chloride; and iodine-containing compounds such as 1,3-diiodo-2-propanol. One or more of these may be used in combination.

[0039] Examples of catalysts include organotin compounds such as dibutyltin diacetate, dibutyltin dioctylate, and dibutyltin dilaurate; organoaluminum compounds such as aluminum tris(acetylacetone), aluminum tris(acetacetate ethyl), and aluminum diisopropoxy(acetacetate ethyl); zirconium(acetylacetone), zirconium tris(acetylacetone), zirconium tetrakis(ethylene glycol monomethyl ether), zirconium tetrakis(ethylene glycol monoethyl ether), and zirconium tetrakis(ethylene glycol monobutyl ether). Examples include organozirconium compounds such as tetratin(ethylene glycol monomethyl ether), titaniumtetratin(ethylene glycol monoethyl ether), and titaniumtetratin(ethylene glycol monobutyl ether); mineral acids such as hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid; organic acids such as formic acid, acetic acid, oxalic acid, and trifluoroacetic acid; inorganic bases such as ammonia, sodium hydroxide, and potassium hydroxide; organic bases such as ethylenediamine and alkanolamine; and amino compounds such as aminosilane, silazane, and amines. One or more of these may be used in combination. Among these, it is preferable that at least one is selected from organotin compounds, organoaluminum compounds, organotitanium compounds, mineral acids, and amino compounds.

[0040] [Release agent composition for molding and vulcanization of rubber products and method for manufacturing the same] The mold release agent composition of the present invention, as described above, contains component (A) and component (B), and exhibits excellent coating properties, excellent mold release properties during the molding vulcanization process of rubber products, and further enables continuous molding vulcanization.

[0041] The surface tension of a 0.1% by weight aqueous dispersion of the mold release agent composition of the present invention at 20°C is not particularly limited, but is preferably 20 to 50 mN / m. When the surface tension is within this range, the adhesion of the mold release agent composition tends to improve. The upper limit of the surface tension is more preferably 45 mN / m, even more preferably 40 mN / m, and particularly preferably 35 mN / m. On the other hand, the lower limit of the surface tension is more preferably 21 mN / m, even more preferably 22 mN / m, and particularly preferably 23 mN / m. The method for measuring the surface tension of a 0.1% by weight aqueous solution of the mold release agent composition at 20°C is the Wilhelmy method. The non-volatile content of the mold release agent composition is the residue when the mold release agent composition is treated at 110°C and its weight becomes constant.

[0042] The pH of a 1% by weight aqueous dispersion of the mold release agent composition of the present invention at 25°C is not particularly limited, but is preferably 3 to 12, more preferably 3 to 11, even more preferably 3 to 10, and most preferably 3 to 9. When the pH is within this range, the handling properties of the mold release agent composition tend to improve.

[0043] The viscosity of the mold release agent composition of the present invention at 25°C is not particularly limited, but is preferably 0.1 to 20,000 mPa·s, more preferably 0.1 to 5,000 mPa·s, even more preferably 1 to 1,000 mPa·s, and particularly preferably 1 to 500 mPa·s. When the viscosity of the mold release agent composition is 0.1 mPa·s or higher, the wettability of the mold release agent composition tends to improve. On the other hand, when the viscosity of the mold release agent composition is 20,000 mPa·s or lower, the coatability of the mold release agent composition tends to improve. The viscosity of the mold release agent composition can be measured using a B-type rotational viscometer, among other methods.

[0044] The mold release agent composition of the present invention may be an emulsified dispersion in water. A mold release agent composition that is an emulsified dispersion in water is preferable because it improves film-forming properties. When the mold release agent composition of the present invention is an emulsion dispersion in water, the average particle size of the emulsion is not particularly limited, but is preferably 0.001 to 200 μm. When the average particle size is 0.001 μm or more, the stability of the mold release agent composition tends to improve, and when the average particle size is 200 μm or less, the film-forming properties tend to improve. The upper limit of the average particle size is more preferably 150 μm, even more preferably 100 μm, and particularly preferably 50 μm. On the other hand, the lower limit of the average particle size is more preferably 0.01 μm, even more preferably 0.05 μm, and particularly preferably 0.1 μm.

[0045] When the release agent composition of the present invention is an emulsified dispersion in water, the water content is not particularly limited, but is preferably 150 to 15,000 parts by weight per 100 parts by weight of component (A). When the content is within the above range, the coating efficiency tends to improve. The upper limit of the content is more preferably 5,000 parts by weight, even more preferably 3,000 parts by weight, and particularly preferably 2,000 parts by weight. On the other hand, the lower limit of the content is more preferably 180 parts by weight, even more preferably 210 parts by weight, and particularly preferably 240 parts by weight.

[0046] Regarding the mold release agent composition of the present invention, a method for producing it includes, for example, a method of mixing component (A), component (B), and, if necessary, component (C), component (D), and other components. In the method for producing the mold release agent composition, there are no particular limitations on the mixing order, etc. All components may be mixed at the same time, or they may be mixed sequentially one by one, or some components may be mixed in advance, and the remaining components or the mixture may be added, mixed, or dispersed in the resulting mixture. There are no particular limitations on the mixing process; it can be carried out using a device with a very simple mechanism, such as a container and a stirring blade. In particular, using mixing devices such as homomixers, homogenizers, colloid mills, and line mixers allows for the efficient production of release agent compositions.

[0047] [Manufacturing method for rubber products and rubber products] The present invention provides a method for manufacturing rubber products by molding and vulcanizing unvulcanized rubber, comprising: step 1, applying the above-mentioned release agent composition to the rubber surface of a bladder and / or the surface of the unvulcanized rubber on the side that comes into contact with the bladder; and step 2, after step 1, heating and expanding the bladder contained in the unvulcanized rubber within a mold to press the side of the unvulcanized rubber that does not come into contact with the bladder against the inner surface of the mold, thereby molding and vulcanizing the unvulcanized rubber. This method allows for the efficient manufacture of rubber products.

[0048] A bladder is a rubber bag used to mold and vulcanize unvulcanized rubber (called a green tire in the case of a tire) by inserting it inside the unvulcanized rubber (on the side that the unvulcanized rubber comes into contact with the bladder). High-temperature, high-pressure gas (for example, steam at about 180°C) or liquid is introduced into the bladder, causing it to expand. This presses the unvulcanized rubber against the mold, heating and pressurizing it to perform the molding and vulcanization process. There are no particular limitations on the shape of the bladder; for example, it can be in the form of a sheet, film, hose, tube, sponge, packing, belt, etc. The bladder may also have grooves to release air during vulcanization molding.

[0049] In step 1, methods for applying the release agent composition to the rubber surface of the bladder and / or the surface of the unvulcanized rubber that comes into contact with the bladder include, for example, spraying it onto the rubber surface of the bladder using a spray gun to atomize it, spraying it onto the rubber surface of the bladder using a fine stream, applying it to the rubber surface of the bladder with a brush, or immersing the rubber surface of the bladder and / or the unvulcanized rubber in the release agent composition.

[0050] In step 1, the release agent composition may be applied to the rubber surface of the bladder and / or the surface of the unvulcanized rubber on the side in contact with the bladder, and then the resulting material may be dried. There are no particular limitations on the drying temperature, but it is preferably 0 to 200°C, more preferably 5 to 190°C, even more preferably 10 to 180°C, and most preferably 15 to 170°C.

[0051] If the release agent composition is applied to the rubber surface of the bladder in step 1, curing may be performed between step 1 and step 2 until a film is formed on the bladder surface. When curing is performed until a film is formed, there are no particular limitations on the duration, but it is preferably 0.01 to 168 hours, more preferably 0.01 to 120 hours, particularly preferably 0.01 to 72 hours, and most preferably 0.01 to 24 hours. When the curing period is within the above range, there is a tendency for the film to be formed efficiently. Furthermore, there are no particular limitations on the ambient temperature for curing the bladder surface before the film is formed, but it is preferably 0 to 200°C, more preferably 5 to 190°C, particularly preferably 10 to 180°C, and most preferably 15 to 170°C. When the ambient temperature is within the above range, the film tends to form efficiently. Also, if drying is performed in step 1, the curing may be performed immediately after drying, or the curing may be performed simultaneously with drying.

[0052] In step 1, if the release agent composition is applied to the surface of the unvulcanized rubber that comes into contact with the bladder, it is believed that when the rubber on the bladder surface comes into contact with the unvulcanized rubber, part or all of the release agent composition will transfer to the rubber on the bladder surface, forming a release-type film on the bladder surface, and enabling efficient continuous molding and vulcanization of rubber products. In this case, the film can also be formed when the unvulcanized rubber is molded and vulcanized.

[0053] The thickness of the coating formed on the bladder surface is not particularly limited, but is preferably 0.01 to 1000 μm, more preferably 0.01 to 500 μm, even more preferably 0.01 to 250 μm, and most preferably 0.1 to 100 μm. When the thickness is within the above range, the productivity of rubber products tends to improve. The weight per unit area of ​​the coating formed on the bladder surface is not particularly limited, but is preferably 0.1 to 200 g / m². 2 more preferably 0.5~150g / m 2 More preferably 1 to 100 g / m² 2 Particularly preferred is 3-50 g / m 2Therefore, when the weight per unit area falls within the above range, the productivity of rubber products tends to improve.

[0054] A bladder having a coating formed from the release agent composition applied in step 1 exhibits good release properties in step 2, which is performed after step 1. Furthermore, it increases the number of times rubber products can be continuously molded and vulcanized, and reduces the defect rate of rubber products. Examples of molding and vulcanization methods in step 2 include calender roll sheet molding, roller head sheet molding, extrusion sheet molding, ram extrusion molding, screw extrusion molding, compression molding, injection molding, and injection molding. The temperature during molding vulcanization in step 2 is not particularly limited, but is preferably 100 to 300°C, more preferably 110 to 260°C, even more preferably 120 to 220°C, and most preferably 130 to 180°C. There are no particular limitations on the pressure during molding vulcanization in step 2, but preferably 0.1 to 50 kgf / cm². 2 , more preferably 0.2 to 45 kgf / cm² 2 More preferably 0.3 to 40 kgf / cm² 2 Particularly preferred is 0.5 to 35 kgf / cm². 2 That is the case.

[0055] Examples of rubber products that can be obtained by the manufacturing method of the present invention include tires, hoses, vibration-damping rubber, automobile belts, seals, fenders, conveyor belts, elastic sleepers, rubber pads, rubber mats, seismic isolation rubber, sealing materials, waterproofing agents, rubber wires, rubber cables, condoms, rubber gloves, rubber balloons, gaskets, packings, rubber balls, etc., with tires being preferred among these. Examples of tires include passenger car tires, truck and bus tires, sports car tires, racing car tires, aircraft tires, motorcycle tires, bicycle tires, buggy tires, agricultural tires, and rubber tracks. [Examples]

[0056] Examples and comparative examples of mold release agent compositions for molding and vulcanization of rubber products will be described below. However, the present invention is not limited to these examples. Furthermore, in the following, the mold release agent composition for molding and vulcanization of rubber products may be referred to simply as "mold release agent composition," and the aqueous dispersion of the mold release agent composition for molding and vulcanization of rubber products may be referred to as "mold release agent aqueous dispersion."

[0057] [Evaluation of stability during storage] The release agent aqueous dispersion was placed in a plastic container and left to stand in constant temperature baths at 5°C, 25°C, and 40°C for one month each, and changes in its state were observed. The stability during storage was evaluated according to the following criteria. ◎: No change in condition was observed at any temperature, indicating excellent stability during storage. ○: Although thickening and separation occur at some temperatures, it is easily redispersed and has slightly better stability during storage. △: At any temperature, it thickens and separates, does not easily redisperse, and has slightly poor stability during storage. ×: At any temperature, the plastic container expands due to gas generation, resulting in poor stability during storage.

[0058] [Coating properties] The weight of the release agent composition adhering to the rubber surface of the bladder (primarily IIR rubber) after drying is 10 g / m². 2 The mold release agent aqueous dispersion was sprayed onto the rubber surface and dried at room temperature (25°C). The coating properties of the mold release agent composition on the resulting treated bladder rubber were visually evaluated according to the following criteria. ○: It is coated 90-100% uniformly on the rubber surface without repelling or unevenness, and has excellent coating properties. △: Although there are some imperfections and unevenness, it is uniformly coated on the rubber surface with a coverage of 70% to less than 90%, resulting in slightly inferior coating properties. ×: There are inconsistencies and unevenness, and less than 70% of the rubber surface is uniformly coated, indicating poor coating performance.

[0059] [Evaluation of mold release properties] The weight of the release agent composition adhering to the rubber surface of the bladder (primarily IIR rubber) after drying is 10 g / m². 2To achieve this, a mold release agent aqueous dispersion was sprayed onto the rubber surface, and the bladder was cured at room temperature (25°C) for 2 hours to obtain the treated bladder. The treated bladder and unvulcanized rubber (mainly IIR) are layered together and heated at 160°C and 20 kgf / cm². 2 The material was press-vulcanized for 20 minutes under the specified conditions. The molded vulcanized evaluation rubber and the bladder rubber sheet were peeled apart at a 180-degree angle, and the required peel load was measured using a tensile testing machine to evaluate the release properties. The release properties were evaluated according to the following criteria, with ◎ and ○ being considered passing grades. Note that if delamination had already occurred at the end of vulcanization, a tensile test could not be performed, but the release properties were undoubtedly excellent, and therefore it was evaluated as ◎. ◎: Peels off with a tensile load of less than 0.5N, exhibiting excellent release properties. ○: Peels off under a tensile load of 0.5N or more and less than 1.0N, indicating slightly superior release properties. △: Peels off under a tensile load of 1.0N or more but less than 1.5N, indicating slightly poor release properties. ×: Peels off under a tensile load of 1.5N or more, indicating poor release properties.

[0060] [Evaluation of repeated mold release properties (continuous vulcanization)] Using the treated bladder used in the above mold release evaluation, the same molding vulcanization method was repeated to measure how many times the mold release properties could be maintained. The more times molding vulcanization can be repeated, the better the repeatable mold release properties. The repeatable mold release properties were evaluated according to the following criteria. ◎: Even after repeated vulcanization 15 or more times, it releases with a tensile load of less than 1.0N, demonstrating excellent repeated release properties. ○: Releases with a tensile load of less than 1.0N between 10 and 15 cycles, exhibiting slightly superior repeated continuous release properties. △: Release occurs with a tensile load of less than 1.0N between 5 and 10 release cycles, and the repeated release properties are somewhat inferior. ×: Release occurs with a tensile load of less than 1.0N in fewer than 5 cycles, resulting in poor repeated release properties.

[0061] [Evaluation of molding and vulcanization of passenger car tires] Surface of a bladder for molding and vulcanizing passenger car tires (surface area: 6000 cm²) 2 The weight of the release agent composition adhering to the rubber surface of the bladder (mainly IIR rubber) after drying is 10 g / m². 2 To achieve this, a mold release agent aqueous dispersion was sprayed onto the rubber surface, and the bladder was cured at room temperature (25°C) for 2 hours to obtain the treated bladder. Using the obtained processed bladder, the molding and vulcanization of passenger car tires was repeatedly performed, and the number of times tires could be produced without defects was measured. The repeated release properties in the molding and vulcanization of passenger car tires were evaluated according to the following criteria. ◎: Even after repeated molding and vulcanization 15 times or more, there is no adhesion and good release properties are maintained. ○: Allows for repeated molding and vulcanization with good release properties and no adhesion for 10 to 15 cycles. △: No adhesion occurs between 5 and 10 times, and repeated molding and vulcanization can be performed with good release properties. ×: No adhesion occurs for less than 5 cycles, and repeated molding and vulcanization can be performed with good release properties.

[0062] [Evaluation of molding and vulcanization of bicycle tires] Surface of a bladder for molding and vulcanizing bicycle tires (surface area: 1500 cm²) 2 The weight of the release agent composition adhering to the rubber surface of the bladder (mainly IIR rubber) after drying is 10 g / m². 2 To achieve this, a mold release agent aqueous dispersion was sprayed onto the rubber surface, and the bladder was cured at room temperature (25°C) for 2 hours to obtain the treated bladder. Using the obtained processed bladder, the molding and vulcanization of bicycle tires was repeatedly performed, and the number of times tires could be produced without defects was measured. The repeated release properties in the molding and vulcanization of bicycle tires were evaluated according to the following criteria. ◎: Even after repeated molding and vulcanization 15 times or more, there is no adhesion and good release properties are maintained. ○: Allows for repeated molding and vulcanization with good release properties and no adhesion for 10 to 15 cycles. △: No adhesion occurs between 5 and 10 times, and repeated molding and vulcanization can be performed with good release properties. ×: No adhesion occurs for less than 5 cycles, and repeated molding and vulcanization can be performed with good release properties.

[0063] (Example 1) A mold release agent composition was obtained by mixing 11 parts by weight of an organosilicon compound and 4 parts by weight of silicone. Next, 15 parts by weight of the obtained release agent composition was added to 85 parts by weight of water and stirred well to obtain an aqueous release agent dispersion. The weight of the release agent composition adhering to the rubber surface of the bladder (primarily IIR rubber) after drying of the obtained release agent aqueous dispersion on the rubber surface of the bladder was 10 g / m². 2 The bladder was coated and cured at room temperature (25°C) for 2 hours to obtain the treated bladder. The resulting treated bladder and unvulcanized rubber are placed on top of each other, and the temperature is set to 160°C and 20 kgf / cm². 2 The material was press-vulcanized for 20 minutes under these conditions. It peeled off after the molding vulcanization was complete, demonstrating excellent release properties. Subsequently, molding vulcanization was repeated using the treated bladder, and the release properties were maintained for more than 15 times, demonstrating excellent repeated release properties. Furthermore, when the resulting release agent aqueous dispersion was placed in a plastic container and left to stand in constant temperature baths at 5°C, 25°C, and 40°C for one month, no change in its state was observed at any of the temperatures, indicating excellent stability during storage.

[0064] (Examples 2-11, Comparative Examples 1-6) In Examples 2-11 and Comparative Examples 1-6, the mold release agent compositions and aqueous dispersions were obtained and evaluated in the same manner as in Example 1, except that the compositions were changed as shown in Tables 1-3. The results are shown in Tables 1-3.

[0065] (Example 12) 15 parts by weight of organosilicon compound 1, 5 parts by weight of silicone 1, 3 parts by weight of POE(7) lauryl ether, and 77 parts by weight of water were mixed and thoroughly stirred to obtain an aqueous dispersion of a mold release agent containing a mold release agent composition. The weight of the release agent composition adhering to the rubber surface of the bladder (primarily IIR rubber) after drying of the obtained release agent aqueous dispersion on the rubber surface of the bladder was 10 g / m².2 The bladder was coated and cured at room temperature (25°C) for 2 hours to obtain the treated bladder. The resulting treated bladder and unvulcanized rubber are placed on top of each other, and the temperature is set to 160°C and 20 kgf / cm². 2 The material was press-vulcanized for 20 minutes under these conditions. It peeled off after the molding vulcanization was complete, demonstrating excellent release properties. Subsequently, molding vulcanization was repeated using the treated bladder, and the release properties were maintained for more than 15 times, demonstrating excellent repeated release properties. Furthermore, when the resulting release agent aqueous dispersion was placed in a plastic container and left to stand in constant temperature baths at 5°C, 25°C, and 40°C for one month, no change in its state was observed at any of the temperatures, indicating excellent stability during storage.

[0066] (Examples 13-19) In Examples 13 to 19, the release agent aqueous dispersions were obtained and evaluated in the same manner as in Example 12, except that the composition was changed as shown in Table 2 in Example 1. The results are shown in Table 2.

[0067] (Example 20) For both the molding and vulcanization bladder for passenger car tires and the molding and vulcanization bladder for bicycle tires, the mold release agent composition obtained in Example 1, applied to the rubber surface of the bladder after drying, was 10 g / m². 2 The material was applied in this manner, cured at room temperature (25°C) for 2 hours, and each treated bladder was obtained. When the treated bladders were used to repeatedly perform molding and vulcanization of passenger car tires and bicycle tires, good release properties were maintained for more than 15 cycles for both passenger car tires and bicycle tires (the evaluation results for both passenger car tires were excellent).

[0068] (Example 21) For both the molding and vulcanization bladder for passenger car tires and the molding and vulcanization bladder for bicycle tires, the mold release agent composition obtained from the mold release agent dispersion in Example 11 was applied to the rubber surface of the bladder after drying, with a concentration of 10 g / m². 2 The material was applied in this manner, cured at room temperature (25°C) for 2 hours, and each treated bladder was obtained. When the treated bladders were used to repeatedly perform molding and vulcanization of passenger car tires and bicycle tires, good release properties were maintained for more than 15 cycles for both passenger car tires and bicycle tires (the evaluation results for both passenger car tires were excellent).

[0069] [Table 1]

[0070] [Table 2]

[0071] [Table 3]

[0072] In Tables 1 and 2, "POE(n)" means "polyoxyethylene with n repeating oxyethylene groups," and "POE(7) lauryl ether" means "polyoxyethylene lauryl ether with 7 repeating oxyethylene groups." Furthermore, Table 4 shows the details of the raw materials used in the above examples and comparative examples.

[0073] [Table 4]

[0074] As can be seen from Tables 1 and 2, the release agent compositions of Examples 1 to 19 are R 1 R 2 SiO 2 / 2 The D units and R shown are indicated by 3 SiO 3 / 2 Having at least one selected from the T units shown in R 1 ~R 3Each of these is an independently monovalent organic group, and the invention contains an organosilicon compound (A) having a hydrolyzable group and a silicone component (B) excluding the organosilicon compound (A), thereby solving the problem of the present invention and further exhibiting excellent stability during storage. On the other hand, in cases where component (A) is not included, as in Comparative Examples 2-6, and in cases where component (B) is not included, as in Comparative Example 1, the problem of the present invention is not solved.

Claims

1. A mold release agent composition for molding and vulcanizing rubber products, comprising an organosilicon compound (A) and a silicone component (B) excluding the organosilicon compound (A), The organosilicon compound (A) is R １ R ２ SiO ２／２ The D units and R shown are indicated by ３ SiO ３／２ It has at least one selected from the T units shown, The aforementioned R １ ~R ３ Each of these is independently a monovalent organic group, The organosilicon compound (A) has hydrolyzable groups, and the total molecular weight of the hydrolyzable groups accounts for 2 to 50% of the molecular weight of the organosilicon compound (A). A mold release agent composition for molding and vulcanizing rubber products.

2. The mold release agent composition for molding and vulcanizing rubber products according to claim 1, wherein the content of component (B) is 10 to 250 parts by weight per 100 parts by weight of the organosilicon compound (A).

3. The mold release agent composition for molding and vulcanizing rubber products according to claim 1 or 2, wherein the organosilicon compound (A) has the T unit.

4. A mold release agent composition for molding and vulcanizing rubber products according to claim 1 or 2, further comprising a surfactant (C).

5. The mold release agent composition for molding and vulcanizing rubber products according to claim 1 or 2, further comprising a water-soluble polymer (D).

6. A method for manufacturing rubber products by molding and vulcanizing unvulcanized rubber, Step 1 involves applying the mold release agent composition for molding and vulcanizing rubber products according to claim 1 or 2 to the rubber surface of the bladder and / or the surface of the unvulcanized rubber on the side in contact with the bladder. A method for manufacturing a rubber product, comprising step 2, after step 1, heating and expanding the bladder contained in the unvulcanized rubber within a mold to press the side of the unvulcanized rubber that is not in contact with the bladder against the inner surface of the mold, thereby molding and vulcanizing the unvulcanized rubber.

7. The method for manufacturing a rubber product according to claim 6, wherein the rubber product is a tire.

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