JPH11198150A - Mold release agent composition for molding and vulcanizing tire, and method for molding and vulcanizing tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the number of times of vulcanizing and to decrease a defective ratio by incorporating specific amounts of a polysiloxane an organosiloxane having an aminoalkyl group and an organosiloxiane having an epoxy group, and setting a dynamic frictional coefficient between butyl rubber after coating and drying and an uncapping butyl rubber to a specific value. SOLUTION: The mold release agent composition contains a fiorganopolysiloxane having 1×10<3> to 1×10<7> centipedes of a complex viscosity at 25 deg.C represented by a general formula, an orgnosiloxane B having an aminoalkyl group, and an organosiloxane C having an epoxy group, wherein R<1> is a monovalent hydrocarbon group having 1-20C unsubstrated or substituted group, R<2> is a hydroxyl group or a 1-5C alkoxy group, n is 100 to 10,000. In this case, a total amount of contents of components A, B, C is 1 to 90 wt.%, and a weight ratio A/B/C is 10 to 90 wt.%/0.5 to 40 wt.%/1 to 50 wt.%. Further, a dynamic frictional coefficient between a butyl rubber after coating and drying and an coating butyl rubber is set to 1 or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold release composition for vulcanizing tires and a method for vulcanizing tires. More specifically, the present invention is used in molding and vulcanizing tires for bicycles, automobiles, other vehicles and aircraft, and provides good releasability and increases the number of times of tire molding and vulcanization using the same bladder. The present invention also relates to a tire mold vulcanizing release agent composition and a tire mold vulcanizing method capable of reducing the defective rate of a tire.

[0002]

2. Description of the Related Art In molding and vulcanizing a tire, a rubber bag (hereinafter, referred to as a bladder) called a bladder or an airbag is a tire before molded and vulcanized (hereinafter, sometimes referred to as a green tire). High temperature and high pressure gas (eg, steam at about 180 ° C) inside the bladder
The green tire is pressed against a mold by heating and pressurizing by introducing liquid and liquid, thereby performing molding 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. Conventional methods include (1) a method of applying a water-based or solvent-based release agent called an inside paint to the inner surface of a green tire each time, and (2) peeling between a green tire and a bladder. There is known a method of applying a silicone-based release agent to the surface of a bladder to improve the performance. As the inside paint, for example, JP-A-53-42243 proposes an aqueous diorganopolysiloxane emulsion in which an inorganic silicate whose surface has been hydrophobized by reaction with an organosilicon compound is dispersed. Japanese Patent Application Laid-Open No. 52-84677 proposes a powder release agent composition comprising a copolymer of a dialkyl polysiloxane and a polyalkylene glycol and mica or talc. Further, as a release agent applied to the bladder surface, for example, JP-A-60-229719 discloses a lubricant composition which is self-crosslinked by carbon dioxide containing an aminoalkyl group-modified organopolysiloxane and a surfactant. JP-A-59-106948 discloses a method in which a mixture of a silicone rubber and a silicone release agent which polymerizes under the action of moisture or heat is applied to a bladder and exposed to air or heat containing moisture. A method of constructing a release agent film on a bladder has been proposed. Further, Japanese Patent Application Laid-Open No. Hei 6-3
No. 39927 discloses a bladder having two or more release lubricating layers in which an innermost layer is provided with a room-temperature-curable silicone layer having an adhesive property to a bladder rubber, and an outermost layer is formed with a condensation-type silicone resin layer. Has been proposed,
No. 275711 proposes a method using a vulcanizing bladder surface-treated with a silicone composition containing an organopolysiloxane, a methylhydrogenpolysiloxane, silica and an organic acid salt of a metal. However, the method of (1) applying the inside paint to the inner surface of the green tire each time has a problem that the process becomes complicated and a stain around the device occurs during the application. In addition, the inside paint enters the joint of the tire inner liner, causing the inner liner joint to peel off, causing trouble such as tire failure, or putting the inside paint applied tire into the molding process. There is a problem that a huge space is required for the stock point till. Also,
(2) In the method of applying a silicone-based release agent to the bladder surface, the technique using a silicone-based water-based release agent does not provide sufficient adhesion between the release agent film and the bladder, Also in the technique using a release agent, although the adhesion effect is slightly improved, there is a problem that peeling occurs during use. The technique proposed in JP-A-6-339927 discloses that two or more layers are coated in order to suppress peeling,
Although the outermost layer that comes into contact with the inner surface of the tire in the early stage of use has a slippery property as a silicone resin layer, it is still insufficient. In recent years, cost reduction in tire production has been strongly demanded, and one of the key points is to reduce the number of times the bladder is replaced in order to reduce the time loss in the process. Also, due to the speeding up of automobile traffic, automobile tires are becoming increasingly wide and low-profile, and improving the slippage of bladders and green tires during molding vulcanization is a key to reducing tire defects. It is an important point.

[0003]

SUMMARY OF THE INVENTION The present invention provides a mold release agent for tire molding and vulcanization which can dramatically increase the number of tire molding vulcanizations using the same bladder and greatly reduce the rate of defective tires. The object of the present invention is to provide a composition and a tire molding vulcanization method.

[0004]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, (A) a terminal hydroxyl group or alkoxy group diorganopolysiloxane having a specific complex viscosity, A release agent composition containing a specific amount of (B) an organosiloxane having an aminoalkyl group and (C) an organosiloxane having an epoxy group, and having a dynamic friction coefficient between butyl rubber after coating and drying and uncoated butyl rubber of 1 or less. By applying to the surface of a bladder having a coating and performing molding vulcanization, it is possible to increase the number of molding vulcanizations using the same bladder and reduce the tire defect rate,
Furthermore, they have found that the releasability can be further improved by blending an inorganic powder or an organic powder with the release agent composition, and based on these findings, the present invention has been completed. That is, the present invention relates to (1) (A) represented by the general formula [1], wherein the complex viscosity at 25 ° C. is 1 × 10
A polysiloxane that is ³ to 1 × 10 ⁷ centipoise,
It contains (B) an organosiloxane having an aminoalkyl group and (C) an organosiloxane having an epoxy group, and the total content of the components (A), (B) and (C) is 1 to 90% by weight. The weight ratio of the components (A), (B) and (C) [(A) / (B) / (C)] is 10 to 90% by weight / 0.5 to 40% by weight. / 1-
50% by weight and a dynamic friction coefficient between butyl rubber after coating and drying and uncoated butyl rubber of 1 or less, a mold release agent composition for tire molding and vulcanization,

Embedded image (Wherein, R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, R ² is a hydroxyl group or an alkoxy group having 1 to 6 carbon atoms, and n is 100 ~ 1
It is 0,000. ), (2) A tire molding composition comprising 0.1 to 50 parts by weight of an inorganic powder or an organic powder with respect to 100 parts by weight of the mold release agent composition for tire molding and vulcanization described in (1). The release agent composition for vulcanization of tires according to the above (1) or (2), on a surface of a bladder for vulcanization of tires having a coating and (3) a coating. The present invention provides a tire molding vulcanization method characterized by applying and performing molding vulcanization of a tire. Further, as a preferred embodiment of the present invention, (4) the release agent composition for tire molding and vulcanization according to (1), wherein the component (A) and the component (B) are emulsified and dispersed in water to form an aqueous emulsion. (5) wherein polyoxyethylene alkyl ether is used as an emulsifier;
The release agent composition for tire molding and vulcanization according to the above item, and (6)
The tire molding and vulcanizing method according to (3), wherein the coating on the bladder surface is formed of a room-temperature-curable silicone rubber;
Can be mentioned.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The mold release vulcanizing composition of the present invention has, as component (A), a hydroxyl group or an alkoxy group at the terminal and a complex viscosity at 25 ° C. of 1 × 10 ³ to
The composition contains a diorganopolysiloxane of 1 × 10 ⁷ centipoise, an organosiloxane having an aminoalkyl group as the component (B), and an organosiloxane having an epoxy group as the component (C). In the composition of the present invention,
The polysiloxane used as the component (A) has a structure represented by the general formula [1].

Embedded image However, in the general formula [1], R ¹ has 1 to 20 carbon atoms.
An unsubstituted or substituted monovalent hydrocarbon group,
R ² is a hydroxyl group or an alkoxy group having 1 to 6 carbon atoms,
n is 100 to 10,000. Examples of the unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms represented by R ¹ include, for example,
Methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl,
Examples thereof include aliphatic hydrocarbon groups such as dodecyl group, tetradecyl group, octadecyl group, and eicosyl group, and aromatic hydrocarbon groups such as phenyl group, tolyl group, benzyl group, phenylpropyl group, and naphthyl group. Examples of the monovalent hydrocarbon group having a substituent having 1 to 20 carbon atoms represented by R ¹ include a hydroxyethoxypropyl group,
Aminopropyl group, aminoethylaminopropyl group, glycidyloxypropyl group, carboxydecyl group, mercaptopropyl group, methacryloyloxypropyl group,
A trifluoropropyl group and the like can be mentioned. Among these polysiloxanes having a hydrocarbon group, (A)
As the main chain structure of the polysiloxane used as a component, dimethylpolysiloxane, methylphenylpolysiloxane and methyltrifluoropropylpolysiloxane can be suitably used, and dimethylpolysiloxane can be particularly preferably used. Examples of the alkoxy group having 1 to 6 carbon atoms represented by R ² include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, and a hexyloxy group.

In the composition of the present invention, the polysiloxane represented by the general formula [1] used as the component (A) is 25 ° C.
Is 1 × 10 ³ to 1 × 10 ⁷ centipoise, more preferably 5 × 10 ³ to 8 × 10 ⁶ centipoise, and still more preferably 1 × 10 ^{4 to} 6 × 10 ⁶ centipoise.
It is centipoise. If the complex viscosity at 25 ° C. of the polysiloxane used as the component (A) is less than 1 × 10 ³ centipoise, the cured film may have insufficient slipperiness and durability. The complex viscosity at 25 ° C. of the polysiloxane used as the component (A) is 1 × 1.
0 exceeds ⁷ centipoise, when in the form dissolved in an organic solvent, or no longer appropriate for spray coating the viscosity of the release agent composition remarkably high, can not be uniformly applied to the bladder surface in the case of brushing, also In the case of an aqueous emulsion form, it may be difficult to obtain a stable release agent composition. In the composition of the present invention, the organosiloxane having an aminoalkyl group used as the component (B) is not particularly limited. For example, γ-aminopropylmethyldimethoxysilane and γ- (N-β-aminoethyl) aminopropylmethyldimethoxy Amino group such as hydrolysis condensate of dialkoxysilane having amino group such as hydrolysis condensate of silane, and co-hydrolysis condensate of γ- (N-β-aminoethyl) aminopropylmethyldimethoxysilane and dimethyldimethoxysilane And a hydrolyzed condensate of a dialkoxysilane having no and an amino group-free dialkoxysilane. In the composition of the present invention, there is no particular limitation on the organosiloxane having an epoxy group used as the component (C), for example, a dialkoxysilane having an epoxy group such as a hydrolyzed condensate of γ-glycidyloxypropylmethyldimethoxysilane. Hydrolyzed condensate, such as co-hydrolyzed condensate of dialkoxysilane having an epoxy group and dialkoxysilane having no epoxy group such as co-hydrolyzed condensate of γ-glycidyloxypropylmethyldimethoxysilane and dimethyldimethoxysilane. Can be mentioned.

In the composition of the present invention, the total content of the components (A), (B) and (C) in the composition is from 1 to 90.
%, More preferably from 10 to 80% by weight. If the total content of the components (A), (B) and (C) is less than 1% by weight, the durability of the coating film formed by coating may be insufficient. When the total content of the components (A), (B) and (C) exceeds 90% by weight,
There is a possibility that the viscosity of the release agent composition becomes extremely high and the coating workability is reduced. In the composition of the present invention, the weight ratio of the component (A), the component (B) and the component (C) [the component (A) / the component (B) / the component (C)] is 10 to 90% by weight / 0.5. -40% by weight / 1-50% by weight. If the proportion of the component (A) is less than 10% by weight, the abrasion resistance of the film formed by coating and drying may be insufficient. If the proportion of the component (A) exceeds 90% by weight, a bladder may be used. There is a possibility that the adhesiveness to the film may be reduced and the wear resistance may be insufficient. If the proportion of the component (B) is less than 0.5% by weight, the adhesion to the bladder may be insufficient, and the proportion of the component (B) may be 40% by weight.
If it exceeds 3, the abrasion resistance may be insufficient. If the proportion of the component (C) is less than 1% by weight, the adhesion to the bladder may be reduced and the abrasion resistance of the coating may be insufficient, and the proportion of the component (C) may be 50% by weight. Exceeds
The wear resistance may be insufficient.

Further, the release agent composition for tire molding and vulcanization of the present invention has a dynamic friction coefficient between butyl rubber after coating and drying and uncoated butyl rubber of 1 or less, more preferably 0.8.
It is as follows. There is no particular limitation on the method of applying and drying the release agent composition to butyl rubber, but usually, the release agent composition is applied to butyl rubber so as to be 7 g per 1,000 cm ² ,
It is preferable to dry by heat treatment at 150 ° C. for 15 minutes. The butyl rubber on which the dry film of the release agent composition has been formed is placed horizontally with the coated surface facing upward, an uncoated butyl rubber sheet (25 × 35 mm) is placed on the coated surface, and a vertical load of 1 kgf and a moving speed of 100 mm / Min, and the dynamic friction coefficient detected at that time is divided by the vertical load to determine the dynamic friction coefficient. When the dynamic friction coefficient exceeds 1, when used for tire molding vulcanization, sufficient slip properties may not be obtained. In the release agent composition of the present invention, the coefficient of kinetic friction between the butyl rubber after coating and drying and the uncoated butyl rubber is preferably small, but it is usually not easy to reduce the kinetic friction coefficient to 0.1 or less.

The form of the release agent composition of the present invention is not particularly limited. For example, it can be a solution dissolved in an organic solvent or an aqueous emulsion emulsified and dispersed in water. Among these, aqueous emulsions are safe,
It can be particularly preferably used in terms of economy and the like. When the composition of the present invention is used as an aqueous emulsion, a surfactant can be added as necessary. The surfactant to be used is not particularly limited, and examples thereof include nonionic surfactants such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, fatty acid monoglyceride, and amine oxide, fatty acid salt, alkylbenzene sulfonate, and alkyl sulfate. Examples include anionic surfactants such as salts, cationic surfactants such as dialkyldimethylammonium chloride and alkylpyridinium chloride, and amphoteric surfactants such as betaine and sulfobetaine. Among these, nonionic surfactants are preferable, and polyoxyethylene alkyl ether can be particularly preferably used. A catalyst such as an organozinc compound, an organotitanium compound, or an organotin compound can be added to the release agent composition of the present invention as needed. As such a catalyst, for example, zinc laurate, zinc acetate, zinc stearate, tin octylate, zinc octylate, tetrapropyl titanate and its partial hydrolyzate, bisdipropoxytitanium,
Bis (acetylacetonate) titanium oxide, titanium lactate, ammonium titanium lactate, dibutyltin dilaurate, dibutyltin dioctate, dioctyltin dilaurate, dioctyltin diacetate, and the like can be given. By the addition of these catalysts, the crosslinking and curing of the polysiloxane can be promoted, and the number of times of vulcanization of the tire with the same bladder can be further increased.

In the composition of the present invention, the component (A) and the component (B)
An inorganic powder or an organic powder can be further added to the release agent composition containing the component and the component (C). Examples of the inorganic powder to be used include mica, kaolin, talc, calcium carbonate, magnesium carbonate, zinc carbonate, graphite, carbon black, carbon fluoride powder, titanium oxide, boron nitride and the like. Examples of the organic powder to be used include fluororesin powder such as Teflon powder, fine particle silicone resin powder, nylon powder, polystyrene powder, paraffin wax, fatty acid amide, fatty acid soap, fatty acid amine salt and the like. One of these organic powders and inorganic powders can be used alone, or two or more can be used in combination. By blending an inorganic powder or an organic powder with the release agent composition, the number of times of vulcanization of the tire with the same bladder can be further increased. In the composition of the present invention, the compounding amount of the inorganic powder or the organic powder is the mold release agent composition for tire molding and vulcanization 1 containing the component (A), the component (B) and the component (C).
The amount is preferably from 0.1 to 50 parts by weight, more preferably from 0.2 to 30 parts by weight, per 100 parts by weight. The compounding amount of the inorganic powder or the organic powder is (A) component, (B)
If the amount is less than 0.1 part by weight per 100 parts by weight of the tire mold vulcanizing release agent composition containing the component and the component (C), the increase in the number of tire molding vulcanizations due to the addition of the inorganic powder or the organic powder increases. The effect may not be sufficiently exhibited. When the amount of the inorganic powder or the organic powder exceeds 50 parts by weight per 100 parts by weight of the tire mold vulcanizing release agent composition containing the component (A), the component (B) and the component (C), There is a possibility that the viscosity of the release agent composition becomes high, which may hinder application to the bladder.

In the tire molding and vulcanizing method of the present invention,
The release agent composition of the present invention is applied to the surface of a tire-forming vulcanization bladder having a coating, and the tire is subjected to molding and vulcanization.
There is no particular limitation on the coating of the bladder for tire molding and vulcanization, and examples thereof include a three-dimensional crosslinkable silicone rubber known as a room temperature-curable silicone rubber, and a thermosetting silicone resin. One of the room-temperature-curable silicone rubber and the thermosetting silicone resin can be used alone, or two or more can be used in combination. Examples of the room temperature curing type silicone rubber include a deoxime type, a deamine type, and a deacetic acid type. Of these, room temperature-curable silicone rubber having a deamine-type curing mechanism can be particularly preferably used because of its good adhesion to the bladder material rubber. In the method of the present invention, mica, kaolin, talc, calcium carbonate, magnesium carbonate, zinc carbonate, graphite, carbon black, carbon fluoride powder, titanium oxide, boron nitride are contained in the composition for forming a film on the bladder. Slippery components such as inorganic powders, organic powders such as fine particle silicone resin powder, nylon powder, Teflon powder, polystyrene powder, paraffin wax, fatty acid amide, fatty acid soap, fatty acid amine salt, straight silicone oil, and modified silicone oil May be used alone or in combination of two or more.

The method of forming a coating on the surface of the bladder used in the method of the present invention is not particularly limited. For example, the coating can be formed by the following method. That is,
After brushing the surface of the bladder, the surface is washed with a solvent, air blow, or the like, and dried at room temperature or under warming conditions. Next, a base coat mainly composed of a room-temperature-curable silicone rubber or a thermosetting silicone resin is applied to the bladder surface by brushing, spraying, or the like. Further, the silicone rubber or silicone resin is cured by the action of moisture-containing air or heat at room temperature or under heating conditions. In the case of forming a film composed of two or more layers, the purpose can be achieved by repeating the application and curing steps a plurality of times using agents having different compositions. In the method of the present invention, when the bladder having the coating is used in the tire molding vulcanization step, the tire molding vulcanization of the present invention containing the components (A), (B) and (C) on the surface of the bladder. A mold release agent composition is applied. When applying the release agent composition of the present invention to the surface of a bladder having a coating, there is no particular limitation on the timing and method of application, and application is performed by a known method such as brush coating, spray coating, or dip coating. Can be. According to the method of the present invention, a coating formed on a bladder surface is obtained by applying the release agent composition of the present invention to the surface of a bladder for molding and vulcanizing a tire having a coating and performing molding and vulcanization of the tire. Of the tire can be suppressed, the slipperiness of the surface can be improved, and the releasability at the time of tire molding and vulcanization can be improved. As a result, the number of times of vulcanization of the tire using the same bladder is significantly increased, the incidence of defective tires due to the close contact between the tire and the bladder is reduced, and efficient tire production can be performed.

[0013]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. The polysiloxane used in Examples and Comparative Examples, the method for measuring the complex viscosity, the method for measuring the dynamic friction coefficient, and the method for testing the vulcanization of bicycle tires and light truck tires are shown below. (1) Polysiloxane (A) Component Polysiloxane A: Complex viscosity at 25 ° C. is 1.0.
A hydroxyl group-terminated dimethylpolysiloxane having a density of × 10 ⁵ centipoise. Polysiloxane B: complex viscosity at 25 ° C. of 1.5
A hydroxyl group-terminated dimethylpolysiloxane having a density of × 10 ⁴ centipoise. Polysiloxane C: complex viscosity at 25 ° C. of 6.0
A hydroxyl group-terminated dimethylpolysiloxane having a density of × 10 ⁶ centipoise. Polysiloxane D: a complex viscosity at 25 ° C. of 4.5
× 10 ⁶ centipoise methylphenylpolysiloxane having both hydroxyl-terminated ends (phenyl group content: 25 mol%). Polysiloxane E: complex viscosity at 25 ° C. of 3.0
A hydroxyl group-terminated methyl trifluoropropyl polysiloxane (× 10 ⁶ centipoise) (trifluoropropyl group content: 10 mol%). Polysiloxane F: complex viscosity at 25 ° C. of 5.5
× 10 ⁶ centipoise dimethylpolysiloxane with both ends capped with a methoxy group. Other components Polysiloxane G: complex viscosity at 25 ° C. is 7.0
A hydroxyl group-capped dimethylpolysiloxane having a molecular weight of 10 ² centipoise. Polysiloxane H: complex viscosity at 25 ° C of 6.0
A dimethylpolysiloxane having a capped end at both ends of a propyl group represented by the formula [2] and having a density of × 10 ⁶ centipoise.

Embedded image Component (B) Polysiloxane I: Complex viscosity at 25 ° C. is 2.1
A hydrolyzed condensate of γ- (N-β-aminoethyl) aminopropylmethyldimethoxysilane having a centipoise of 00 centipoise. Polysiloxane J: complex viscosity at 25 ° C. of 1.8
A hydrolyzed condensate of γ-aminopropylmethyldimethoxysilane having a centipoise of 00. Polysiloxane K: complex viscosity at 25 ° C. of 1.5
A co-hydrolysis condensate of 00 centipoise of γ- (N-β-aminoethyl) aminopropylmethyldimethoxysilane and dimethyldimethoxysilane (molar ratio = 9/1). Component (C) Polysiloxane L: Complex viscosity at 25 ° C. is 780
A hydrolyzed condensate of γ-glycidyloxypropylmethyldimethoxysilane which is centipoise. Polysiloxane M: complex viscosity at 25 ° C. of 460
Co-hydrolysis condensate of γ-glycidyloxypropylmethyldimethoxysilane and dimethyldimethoxysilane (molar ratio = 9/1) as centipoise. The complex viscosity of the polysiloxane was determined by using a controlled stress rheometer CS type (manufactured by Bolin Corporation), using a 20 mmφ cone plate as a fixture, and estimating a natural frequency of 0.1 rad / s at 25 ° C. Was measured. (2) Measurement method of kinetic friction coefficient The kinetic friction coefficient between the butyl rubber sheet surface coated with a release agent and heated at 150 ° C. for 15 minutes and the uncoated butyl rubber sheet surface is measured by the following method. did. That is, the butyl rubber sheet on which the release agent composition has been applied and dried is placed horizontally with the coated side facing upward, and the uncoated butyl rubber sheet with the iron plate bonded to the coated side with the rubber sheet side facing down. And further put a 1 kg weight on it, using a friction coefficient measuring device [manufactured by Tester Sangyo Co., Ltd.]
The dynamic friction force was measured at a moving speed of 100 mm / min. The measured dynamic friction force (kgf) was divided by 1 kgf to calculate a dynamic friction coefficient. (3) Bicycle tire molding vulcanization test method A paper towel impregnated with a commercially available white spirit (boiling point: 100 to 140 ° C) a bicycle tire molding vulcanization bladder having a release agent application area of 1,300 cm ^2. And dried for 1 day. Then, a deamination type silicone RTV [manufactured by PACKER CHEMIE GmbH, VP
80g of a solution prepared by using white spirit to have a nonvolatile content of 18% by weight was applied to the surface of a bladder using an air spray, and cured at room temperature to form a film on the surface. When used for tire molding vulcanization, before the first vulcanization, 10 molding vulcanizations on the surface of the bladder,
The release agent composition was applied by brush application at 30 times, 100 times, and thereafter every 100 times, at a time, and dried.
During tire molding vulcanization, the bladder peeling state and the state of the tire inner surface were observed every 10 tire moldings, and when either a decrease in the peeling state or adhesion of a release agent to the tire inner surface was observed, The vulcanization of the tire was stopped, and the number of tires up to that point was determined. (4) Light truck tire molding vulcanization test method A light truck tire molding vulcanization bladder with a release agent application area of 6,000 cm ² is wiped off and washed with white spirit as in the case of bicycle tires. After drying for one day, the deamination type silicone RTV [WAKE
250 g of a 18% by weight non-volatile content white spirit solution of VP-1069] manufactured by R Chemie GmbH was applied to the surface of the bladder using an air spray, and cured at room temperature to form a film on the surface. When used for tire molding vulcanization, on the surface of the bladder, before the first vulcanization, before the second vulcanization, the number of molding vulcanizations was 100, and thereafter, every 100 moldings, up to 400 molding vulcanizations, the release agent composition 60 things at a time
g, applied by brushing and dried. During tire molding vulcanization, the bladder peeling state and the state of the tire inner surface were observed every 10 tire moldings, and when any of a decrease in the peeling state or adhesion of a release agent to the tire inner surface was observed, The vulcanization of the tire was stopped, and the number of tires up to that point was determined. Example 1 50 parts by weight of polysiloxane A as component (A), 15 parts by weight of polysiloxane I as component (B), 5 parts by weight of polysiloxane L as component (C), 3 parts by weight of zinc laurate, and lauryl alcohol ethylene oxide (10 mol) 1) 1 part by weight of the adduct was blended and emulsified and dispersed in 26 parts by weight of water to prepare a mold release agent composition for tire molding and vulcanization. The coefficient of kinetic friction of the butyl rubber sheet coated with the composition and dried on the uncoated butyl rubber sheet was 0.40. As a result of the molding vulcanization test, 700 bicycle tires and 500 light truck tires were obtained. Example 2 A release agent composition for tire molding and vulcanization was prepared in the same manner as in Example 1 except that polysiloxane B was used as the component (A). The coefficient of dynamic friction of the butyl rubber sheet coated with this composition and dried on an uncoated butyl rubber sheet was 0.7.
It was 5. As a result of the molding vulcanization test, 500 bicycle tires and 350 light truck tires were obtained. Examples 3 to 9 Seven types of tire mold vulcanizing release agent compositions having the compositions shown in Table 1 were prepared in the same manner as in Example 1, the dynamic friction coefficient was measured, and a bicycle tire and a light track were prepared. Vulcanization test of tires for automobiles. Table 1 shows the results of Examples 1 to 9.

[0014]

[Table 1]

[0015]

[Table 2]

Example 10 0.73 parts by weight of polysiloxane A as component (A), (B)
0.222 parts by weight of polysiloxane I as a component, 0.07 parts by weight of polysiloxane L as a component (C), 0.03 part by weight of zinc laurate, and lauryl alcohol ethylene oxide
(10 mol) 0.01 parts by weight of an adduct was mixed, and 98.94 of water was added.
The mixture was emulsified and dispersed in parts by weight to prepare a mold release agent composition for tire molding and vulcanization. The coefficient of dynamic friction of an uncoated butyl rubber sheet of a butyl rubber sheet coated and dried with this composition is
0.75. As a result of the molding vulcanization test, 500 bicycle tires and 350 light truck tires were obtained. Example 11 64 parts by weight of polysiloxane A as component (A), 19 parts by weight of polysiloxane I as component (B), 6 parts by weight of polysiloxane L as component (C), 3 parts by weight of zinc laurate, and lauryl alcohol ethylene oxide (10 mol ) 1 part by weight of the adduct was blended and emulsified and dispersed in 7 parts by weight of water to prepare a mold release agent composition for tire molding and vulcanization. The coefficient of kinetic friction of the butyl rubber sheet coated with the composition and dried on the uncoated butyl rubber sheet was 0.70. As a result of the molding vulcanization test, 650 bicycle tires and 450 light truck tires were obtained. Examples 12 to 17 Six kinds of mold release agents for tire vulcanization having the compositions shown in Table 2 were prepared in the same manner as in Example 10, the dynamic friction coefficient was measured, and the tires for bicycles and lights were prepared. A molding vulcanization test of a truck tire was performed. Example 10
The results of Nos. To 17 are shown in Table 2.

[0017]

[Table 3]

[0018]

[Table 4]

Example 18 (A) 50 parts by weight of polysiloxane A, (B) 15 parts by weight of polysiloxane I, (C) 5 parts by weight of polysiloxane L, 3 parts by weight of zinc laurate and ethylene oxide lauryl alcohol (10 moles) 1 part by weight of the adduct was blended and emulsified and dispersed in 26 parts by weight of water, and mica (Taika Co., Ltd., natural muscovite NT-7) was further added as an inorganic powder.
0] of 0.2 parts by weight to prepare a release agent composition for tire molding and vulcanization. The coefficient of kinetic friction of the butyl rubber sheet coated with the composition and dried on an uncoated butyl rubber sheet was 0.30. As a result of the molding vulcanization test, 800 tires for bicycles and 60 tires for light trucks were used.
There were zero. Example 19 A release agent composition for tire molding and vulcanization was prepared in the same manner as in Example 18, except that the amount of mica as the inorganic powder was changed to 30 parts by weight. The coefficient of dynamic friction of the butyl rubber sheet coated with the composition and dried was 0.25 with respect to the uncoated butyl rubber sheet. As a result of the molding vulcanization test, 1,200 bicycle tires and 700 light truck tires were obtained. Example 20 A release agent composition for tire molding and vulcanization in the same manner as in Example 18, except that 5 parts by weight of calcium carbonate [reagent first grade] was used instead of 0.2 parts by weight of mica as an inorganic powder. Was prepared. The coefficient of dynamic friction of the butyl rubber sheet coated with this composition and dried on an uncoated butyl rubber sheet was 0.3.
It was 5. As a result of the molding vulcanization test, 750 bicycle tires and 550 light truck tires were obtained. Example 21 As a powder, calcium carbonate as an inorganic powder [Reagent 1]
Grade] and 10 parts by weight of Teflon powder [Daikin Industries, Ltd., Lubron LD-1] which is an organic powder, in the same manner as in Example 18, except that the release agent for tire molding and vulcanization was used. A composition was prepared. The coefficient of kinetic friction of the butyl rubber sheet coated with the composition and dried on the uncoated butyl rubber sheet was 0.15. As a result of the molding vulcanization test, 1,000 bicycle tires and 700 light truck tires were obtained. Table 3 shows the results of Examples 18 to 21.

[0020]

[Table 5]

Comparative Example 1 The procedure of Example 1 was repeated, except that the polysiloxane G having a complex viscosity of 7.0 × 10 ² centipoise at 25 ° C. was used in place of the polysiloxane as the component (A). ,
A release agent composition for tire molding vulcanization was prepared. The coefficient of dynamic friction of the butyl rubber sheet coated with this composition and dried was 1.10. As a result of the molding vulcanization test, 250 bicycle tires and 150 light truck tires were obtained. Comparative Example 2 Same as Example 1, except that 64 parts by weight of polysiloxane A was used as the component (A), 4.5 parts by weight of polysiloxane I was used as the component (B), and 1.5 parts by weight of polysiloxane L was used as the component (C). Thus, a mold release composition for vulcanization of a tire was prepared. The coefficient of kinetic friction of the butyl rubber sheet coated with this composition and dried on the uncoated butyl rubber sheet was 1.10.
Met. As a result of the molding vulcanization test, 200 bicycle tires and 100 light truck tires were obtained. Comparative Example 3 Same as Example 1 except that 6.9 parts by weight of polysiloxane A was used as component (A), 28 parts by weight of polysiloxane I was used as component (B), and 35.1 parts by weight of polysiloxane L was used as component (C). Thus, a mold release composition for vulcanization of a tire was prepared. The coefficient of kinetic friction of the butyl rubber sheet coated with this composition and dried on an uncoated butyl rubber sheet was 1.3.
It was 0. As a result of the molding vulcanization test, 150 bicycle tires and 50 light truck tires were obtained. Comparative Example 4 A tire was prepared in the same manner as in Example 1 except that 37 parts by weight of polysiloxane A was used as the component (A), 29 parts by weight of polysiloxane I was used as the component (B), and 4 parts by weight of polysiloxane L was used as the component (C). A mold release composition for vulcanization was prepared.
The coefficient of kinetic friction of the butyl rubber sheet coated with the composition and dried on the uncoated butyl rubber sheet was 1.15. The result of the molding vulcanization test showed that the bicycle tire was 150
And 50 light truck tires. Comparative Example 5 Same as Example 1 except that 60 parts by weight of polysiloxane A was used as the component (A), 0.3 parts by weight of polysiloxane I was used as the component (B), and 9.7 parts by weight of polysiloxane L was used as the component (C). Thus, a mold release composition for vulcanization of a tire was prepared. The coefficient of kinetic friction of the butyl rubber sheet coated with this composition and dried on the uncoated butyl rubber sheet was 1.10.
Met. As a result of the molding vulcanization test, 300 bicycle tires and 150 light truck tires were obtained. Comparative Example 6 A tire was prepared in the same manner as in Example 1, except that 24 parts by weight of polysiloxane A was used as the component (A), 10 parts by weight of polysiloxane I was used as the component (B), and 36 parts by weight of polysiloxane L was used as the component (C). A mold release composition for vulcanization was prepared. The coefficient of kinetic friction of the butyl rubber sheet coated with the composition and dried on the uncoated butyl rubber sheet was 1.45. The result of the molding vulcanization test was that the bicycle tire was 1
There were 00 tires and 20 light truck tires. Comparative Example 7 53.4 parts by weight of polysiloxane A as component (A), (B)
A release agent composition for tire molding and vulcanization was prepared in the same manner as in Example 1 except that 16 parts by weight of polysiloxane I was used as a component and 0.6 parts by weight of polysiloxane L was used as a component (C). The coefficient of dynamic friction of the butyl rubber sheet coated with the composition and dried on an uncoated butyl rubber sheet was 1.2.
It was 0. As a result of the molding vulcanization test, 200 bicycle tires and 100 light truck tires were obtained. Comparative Example 8 0.6 parts by weight of polysiloxane A as component (A), 0.2 parts by weight of polysiloxane I as component (B), 0.06 parts by weight of polysiloxane L as component (C) and 95.14 parts by weight of water A release agent composition for tire molding and vulcanization was prepared in the same manner as in Example 1 except for the difference. The coefficient of dynamic friction of the butyl rubber sheet coated with this composition and dried was 1.30 with respect to the uncoated butyl rubber sheet. As a result of the molding vulcanization test, 150 bicycle tires and 50 light truck tires were obtained. Comparative Example 9 Example 1 was repeated except that 67 parts by weight of polysiloxane A was used as the component (A), 20 parts by weight of polysiloxane I was used as the component (B), and 7 parts by weight of polysiloxane L and 2 parts by weight of water were used as the component (C). Similarly, a release agent composition for tire molding and vulcanization was prepared. Since the release agent composition had a high viscosity and could not be applied to the bladder surface, a tire molding vulcanization test was not performed. Comparative Example 10 Instead of the polysiloxane as the component (A), dimethyl-
A mold release vulcanizing composition for tire molding and vulcanization was prepared in the same manner as in Example 1 except that polysiloxane H having a structure represented by the formula [2] and having both ends blocked by an n-propylsilyl group was used. Prepared. The coefficient of dynamic friction of the butyl rubber sheet coated with the composition and dried was 1.05 with respect to the uncoated butyl rubber sheet. The result of the molding vulcanization test is
There were 280 bicycle tires and 100 light truck tires. Comparative Example 11 A tire molding vulcanization test was performed without using the release agent composition. As a result, there were 50 bicycle tires and 10 light truck tires. Table 4 shows the results of Comparative Examples 1 to 11.

[0022]

[Table 6]

[0023]

[Table 7]

In Examples 1 to 21 in which the tire was vulcanized by the method of the present invention using the release agent composition for molding and vulcanizing of the tire of the present invention, the same bladder was used for the bicycle tire. , And over 350 tires for light truck tires could be molded and vulcanized. When the release agent compositions of Examples 1 to 17 containing no inorganic powder or organic powder are used, the average number of bicycle tires is about 590,
Examples 18 to 2 in which an inorganic powder or an organic powder was blended, while the average number of light truck tires was about 410.
When the release agent composition of No. 1 was used, an average of about 940 bicycle tires and an average of about 64 light truck tires were used.
0, the (A) component, the (B) component and the mold release agent composition for vulcanization containing tire containing the component (C), further blending an inorganic powder or an organic powder, the same It can be seen that the method is effective for increasing the number of times of vulcanizing a tire using a bladder. On the other hand, Comparative Example 1 using polysiloxane G having a low complex viscosity instead of component (A), component (A), component (B)
Comparative Example 2, wherein the ratio of the component (A) to the total of the components and the component (C) exceeds 90% by weight, and the ratio of the component (A) to the total of the components (A), (B) and (C) is 10 Weight percent,
Comparative Example 3, in which the ratio of the component (C) exceeds 50% by weight, Comparative Example 4, in which the ratio of the component (B) to the total of the components (A), (B), and (C) exceeds 40% by weight, A) component, (B) component,
Comparative Example 5, wherein the ratio of the component (B) to the total of the components (C) is less than 0.5% by weight, the ratio of the component (C) to the total of the components (A), (B) and (C) is Comparative Example 6 exceeding 50% by weight, (C) based on the total of components (A), (B) and (C)
Comparative Example 7 in which the ratio of the components is less than 1% by weight, and Comparative Example 8 in which the total content of the components (A), (B) and (C) in the release agent composition is less than 1% by weight. Comparative Example 10 using polysiloxane having both ends blocked by n-propyl groups instead of component (A) in the release agent composition, and Comparative Example 11 using no release agent composition at all The number of tire moldings using the same bladder was 300 or less for bicycle tires and 150 or less for light truck tires. In addition, the release agent composition of Comparative Example 9 in which the total content of the components (A), (B) and (C) exceeds 90% by weight can be applied to a bladder because of its high viscosity. Did not.

[0025]

EFFECTS OF THE INVENTION According to the release agent composition for tire vulcanization and the method for vulcanizing a tire of the present invention, good release properties can be obtained during the vulcanization of bicycles, automobiles, other vehicle and aircraft tires. The moldability is obtained, the number of tire molding vulcanization using the same bladder is increased, the tire defect rate is reduced,
The productivity of tire molding vulcanization can be improved.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 83/08 C08L 83/08 // (C08K 13/02 5:54 3:00 5:00) B29K 105: 24 B29L 30: 00 (72) Inventor Masaki Tanaka 2-6-1 Otemachi, Chiyoda-ku, Tokyo Shin-Etsu Chemical Co., Ltd. Silicone Business Division

Claims (3)

[Claims] 1. A polysiloxane represented by the general formula [1] having a complex viscosity of 1 × 10 ³ to 1 × 10 ⁷ centipoise at 25 ° C .; (B) an organosiloxane having an aminoalkyl group; (C) It contains an organosiloxane having an epoxy group, and the total content of the components (A), (B) and (C) is 1 to 90% by weight,
The weight ratio of the components (A), (B) and (C) [(A)
Component / (B) component / (C) component] is 10 to 90% by weight /
0.5 to 40% by weight / 1 to 50% by weight, and a dynamic friction coefficient between butyl rubber after coating and drying and uncoated butyl rubber is 1 or less, a mold release agent for tire molding and vulcanization. Composition. Embedded image (Wherein, R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, R ² is a hydroxyl group or an alkoxy group having 1 to 6 carbon atoms, and n is 100 ~ 1
It is 0,000. ) 2. An inorganic powder or an organic powder 0.1 with respect to 100 parts by weight of the release agent composition for tire molding and vulcanization according to claim 1.
A mold release composition for vulcanization and vulcanization of tires, which comprises 50 to 50 parts by weight. 3. A method of applying a mold release vulcanizing composition for tire molding and vulcanization according to claim 1 to a surface of a bladder for tire molding and vulcanization having a coating film to perform molding and vulcanization of a tire. Characteristic tire molding vulcanization method.