JP2006225636A - Liquid silicone rubber coating composition and air bag using the composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid silicone rubber coating agent composition that yields a cured product excellent in the adhesion to fibers, rubber strength and blocking resistance and to provide an air bag having a rubber coating layer comprising the cured product. <P>SOLUTION: The liquid silicone rubber coating agent composition comprises (A) an organopolysiloxane containing at least two silicon atom-bonded alkenyl groups in one molecule, (B) an organohydrogenpolysiloxane containing at least two silicon atom-bonded hydrogen atoms in one molecule, (C) an addition reaction catalyst, (D) a gel method silica having a BET specific surface area of 260-500 m<SP>2</SP>/g and an average particle size of 0.5-20 μm and (E) an adhesion improver. The air bag has a rubber coating layer comprising a cured product of the composition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid silicone rubber coating agent composition that is a cured product excellent in adhesion to fibers, rubber strength, blocking resistance, and the like, and an airbag having a rubber coating layer made of a cured product of the composition.

  Conventionally, silicone rubber-coated cloth intended to form a rubber film on the fiber surface has a sticky feeling peculiar to silicone rubber, so that the workability at the time of cutting or sewing after coating has been extremely poor. As an improvement measure, powder such as talc, which has excellent adhesion and slipperiness, is dusted on the rubber surface. However, this method is expensive and has a risk of adversely affecting the human body due to dust. In addition, since the powder is simply adhered to the surface of the rubber-coated cloth, the powder is easily removed and the effect cannot be exhibited stably.

In order to solve these problems, the following compositions have been proposed. For example, a powder of an inorganic compound or an organic compound selected from the group consisting of aluminum hydroxide, mica, dimethylsilsesquioxane, carbon, polyamide and polyfluorinated ethylene having an average particle size of 0.5 to 20 μm is used as the rubber coating composition. A coating composition for a rubber coated fabric obtained by adding a body (Patent Document 1); a dry oil compound selected from a natural drying oil, a modified natural drying oil, a liquid diene compound or unsaturated fatty acid esters in a rubber coating composition Coating composition for low-viscosity rubber coated fabrics added (Patent Document 2); aluminosilicate hollow powder having an average particle size of 10 to 300 μm, glass balloon, silica balloon, shirasu balloon, carbon Balloon, alumina balloon, plastic balloon, silicone A coating composition for rubber coating cloth having a low adhesiveness on the surface of a rubber coating film to which a hollow powder such as resin hollow powder, alumina powder, glass powder, plastic powder or the like is added (Patent Document 3); rubber A coating composition for rubber-coated cloth with reduced tackiness, which is obtained by adding wet silica having an average BET specific surface area of 150 to 250 m ² / g and an average particle diameter of 20 μm or less to the coating composition (Patent Document 4) ) Etc. have been proposed.

  However, none of the compositions improved the workability after curing, but did not become a cured product satisfying blocking resistance while maintaining various properties such as adhesion to fibers and rubber strength.

Japanese Patent No. 3379839 JP 2000-191915 A JP 2000-303022 A JP 2001-59052 A

  The present invention has been made in view of the above circumstances, and is a liquid silicone rubber coating composition that is a cured product having excellent adhesion to fibers, rubber strength, and blocking resistance, and a rubber coating comprising the cured product. An object is to provide an air bag having a layer.

  As a result of intensive studies to achieve the above object, the present inventor has made the present invention.

That is, the present invention firstly
(A) Organopolysiloxane containing an alkenyl group bonded to at least two silicon atoms in one molecule: 100 parts by mass
(B) Organohydrogenpolysiloxane containing hydrogen atoms bonded to at least two silicon atoms in one molecule: silicon atoms in the composition with respect to 1 mol of alkenyl groups bonded to the silicon atoms in the composition An amount of 1 to 7 moles of hydrogen atoms bonded to
(C) addition reaction catalyst: effective amount,
(D) Gel method silica having a BET specific surface area of 260 to 500 m ² / g and an average particle size of 0.5 to 20 μm: 1 to 50 parts by mass, and (E) an adhesion improver: 0.1 to 10 parts by mass A liquid silicone rubber coating composition comprising:
I will provide a.

  In addition, the present invention secondly provides an airbag having a rubber coating layer made of a cured product of the composition.

  The cured product obtained by curing the liquid silicone rubber coating agent composition of the present invention not only has excellent adhesion to fibers, rubber strength and anti-blocking property, but also has a reduced feeling of stickiness peculiar to rubber and a good hand feeling. In addition, it has excellent workability during sewing. In addition, the composition is excellent in coating properties and is also environmentally friendly because it can be used without being diluted in a solvent. An airbag having a rubber coating layer made of the cured product is less likely to peel off because the rubber coating layer is difficult to peel off, and is excellent in sustainability of the inflation time.

  Hereinafter, the present invention will be described in detail.

<Liquid silicone rubber coating composition>
The liquid silicone rubber coating agent composition of the present invention comprises the following components (A) to (E).

-(A) Organopolysiloxane-
The (A) component organopolysiloxane is a main component of the composition, and on average, an alkenyl group (hereinafter referred to as “silicon”) bonded to at least 2, preferably 2 to 20, silicon atoms in one molecule. Containing an atom-bonded alkenyl group).

  The silicon-bonded alkenyl group usually has 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms. Specific examples thereof include a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, and a heptenyl group, and a vinyl group is preferable.

  The bonding position of the silicon atom-bonded alkenyl group in the organopolysiloxane molecule may be the molecular chain terminal, the molecular chain non-terminal (ie, molecular chain side chain), or both. Good.

  In the organopolysiloxane molecule of this component, an organic group bonded to a silicon atom other than the silicon atom-bonded alkenyl group (hereinafter referred to as “silicon atom-bonded organic group”) does not have an aliphatic unsaturated bond. For example, an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms may be used. Examples of the unsubstituted or substituted monovalent hydrocarbon group include an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, and a heptyl group; a cycloalkyl group such as a cyclohexyl group; Aryl groups such as a group, tolyl group, xylyl group and naphthyl group; aralkyl groups such as a benzyl group and a phenethyl group; some or all of hydrogen atoms of these groups are halogen atoms such as a chlorine atom, a fluorine atom and a bromine atom Substituted halogenated alkyl groups such as chloromethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, etc. are mentioned, preferably alkyl group and aryl group, more preferably methyl group , A phenyl group.

  In this component, the content of the silicon-bonded alkenyl group is preferably 0.001 to 10 mol%, particularly preferably 0.01 to 5 mol%, based on all silicon-bonded organic groups in the component.

  The molecular structure of the organopolysiloxane of this component is not particularly limited, and examples thereof include linear, partially branched linear, cyclic, branched, etc., but the main chain is basically a diorganosiloxane unit. It is preferably a linear diorganopolysiloxane having both ends of the molecular chain blocked with triorganosiloxy groups.

  The viscosity at 25 ° C. of this component is preferably 100 to 500,000 mPa · s, particularly because physical properties such as adhesion to cured fibers, rubber strength, blocking resistance, and workability are more excellent. Preferably, it is 300 to 100,000 mPa · s.

Examples of the organopolysiloxane of this component include an average composition formula (1):
R ¹ _a R ² _b SiO _{(4-ab) / 2} (1)
Wherein R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bond, R ² is an alkenyl group, a is a number from 1.7 to 2.1, and b is 0.00001 to A number of 0.1, provided that a + b satisfies 1.8 to 2.2)
The thing represented by is mentioned.

In the average composition formula (1), the unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bond represented by R ¹ has usually 1 to 12 carbon atoms, preferably 1 to 1 carbon atoms. 10 things. Specific examples thereof include those exemplified as the silicon atom-bonded organic group other than the silicon atom-bonded alkenyl group.

The alkenyl group represented by R ² has 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms. Specific examples thereof include those exemplified as the silicon atom-bonded alkenyl group.

  a is preferably a number from 1.9 to 2.0, b is preferably a number from 0.0001 to 0.05, and a + b preferably satisfies 1.95 to 2.05.

Specific examples of the organopolysiloxane of this component include a trimethylsiloxy group-capped dimethylsiloxane / methylvinylsiloxane copolymer with both ends of a molecular chain, a trimethylsiloxy group-capped methylvinylpolysiloxane with a molecular chain at both ends, a trimethylsiloxy group with both ends of a molecular chain Blocked dimethylsiloxane / methylvinylsiloxane / methylphenylsiloxane copolymer, dimethylvinylsiloxy group blocked at both ends of molecular chain, dimethylvinylsiloxy group blocked at both ends of molecular chain, methylvinylpolysiloxane blocked at both ends of molecular chain, dimethylvinylsiloxy group at both ends of molecular chain Blocked dimethylsiloxane / methylvinylsiloxane copolymer, dimethylvinylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane / methylphenylsiloxane copolymer, both ends of molecular chain Divinylmethylsiloxy group-blocked dimethylpolysiloxane, molecular chain both ends divinylmethylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane copolymer, molecular chain both ends trivinylsiloxy group-blocked dimethylpolysiloxane, molecular chain both ends trivinylsiloxy group-blocked Dimethylsiloxane / methylvinylsiloxane copolymer, formula: R ¹ ₃ SiO _1/2 (wherein R ¹ is as described above, the same shall apply hereinafter) and a formula: R ¹ ₂ R ² SiO _1/2 (wherein R ² is as described above, the same shall apply hereinafter) represented by a siloxane unit represented by formula: R ¹ ₂ SiO and a small amount represented by formula: SiO ₂ An organosiloxane copolymer comprising a siloxane unit, and a siloxane unit represented by the formula: R ¹ ₃ SiO _1/2 Organosiloxane copolymer comprising a siloxane unit represented by the formula: R ¹ ₂ R ² SiO _1/2 and a siloxane unit represented by the formula: SiO ₂ , represented by the formula: R ¹ ₂ R ² SiO _1/2 An organosiloxane copolymer comprising a siloxane unit represented by the formula: R ¹ ₂ SiO and a small amount of a siloxane unit represented by the formula: SiO ₂ ; represented by the formula R ¹ R ² SiO Organosiloxane copolymers comprising a siloxane unit and a small amount of a siloxane unit represented by the formula: R ¹ SiO _3/2 or a small amount of a siloxane unit represented by the formula: R ² SiO _3/2 , and these organopolysiloxanes The mixture which consists of 2 or more types of these is mentioned.

  The (A) component organopolysiloxane may be used alone or in combination of two or more.

-(B) Organohydrogenpolysiloxane-
The (B) component organohydrogenpolysiloxane is a component that acts as a crosslinking agent in the addition curing reaction with the (A) component and further imparts adhesiveness to the cured product. This organohydrogenpolysiloxane has an average of at least 2, preferably at least 3, more preferably an upper limit of 500, even more preferably an upper limit of 200, and particularly preferably an upper limit of 100 per molecule. Those having a hydrogen atom bonded to an atom (hereinafter referred to as “silicon atom-bonded hydrogen atom” (that is, SiH group)), and preferably having no aliphatic unsaturated bond in the molecule.

  The bonding position of the silicon atom-bonded hydrogen atom in the organohydrogenpolysiloxane molecule of this component may be the molecular chain terminal, the molecular chain non-terminal, or both.

  In this organohydrogenpolysiloxane molecule, the silicon atom-bonded organic group other than the silicon atom-bonded hydrogen atom is not particularly limited, but preferably has no aliphatic unsaturated bond, for example, unsubstituted or substituted. The monovalent hydrocarbon group etc. whose carbon atom number is 1-10 normally, Preferably it is 1-6 are mentioned. Specific examples thereof include those exemplified as the silicon atom-bonded organic group other than the silicon atom-bonded alkenyl group in the description of the component (A), and alkenyl groups such as a vinyl group and an allyl group.

  In this component, the content of the silicon atom-bonded hydrogen atoms is preferably 0.1 to 60 mol%, particularly preferably based on the total of all silicon atom-bonded organic groups and all silicon atom-bonded hydrogen atoms in the component. 1 to 50 mol%.

  The molecular structure of the organohydrogenpolysiloxane of this component is not particularly limited and those conventionally produced can be used, for example, linear, cyclic, branched, three-dimensional network structure (resinous), etc. Linear or cyclic is preferable.

  The viscosity of this component at 25 ° C. is more excellent in physical properties and workability such as adhesion to cured fibers, rubber strength, blocking resistance, etc., preferably 0.1 to 5,000 mPa · s, more A range that is liquid at room temperature (25 ° C.), preferably 0.5 to 1,000 mPa · s, particularly preferably 5 to 500 mPa · s, is desirable. When satisfying such viscosity, the number of silicon atoms (or the degree of polymerization) in one molecule of the organohydrogenpolysiloxane is usually 2 to 1,000, preferably 3 to 300, more preferably 4 to 150. .

Examples of the organohydrogenpolysiloxane of this component include an average composition formula (2):
R ³ _c H _d SiO _{(4-cd) / 2} (2)
Wherein R ³ is an unsubstituted or substituted monovalent hydrocarbon group, c is a number from 0.7 to 2.1, d is a number from 0.001 to 1.0, provided that c + d satisfies 0.8 to 3.0. )
The thing represented by is mentioned.

In the average composition formula (2), the unsubstituted or substituted monovalent hydrocarbon group represented by R ³ has 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms. This monovalent hydrocarbon group is preferably one having no aliphatic unsaturated bond such as an alkenyl group. Specific examples of the unsubstituted or substituted monovalent hydrocarbon group include those exemplified as the silicon atom-bonded organic group other than the silicon atom-bonded alkenyl group in the description of the component (A), vinyl group, allyl group, and the like. An alkenyl group etc. are mentioned.

  c is preferably a number from 1.0 to 2.0, d is preferably a number from 0.01 to 1.0, and c + d is preferably a number from 1.5 to 2.5.

Specific examples of the organohydrogenpolysiloxane of this component include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, methylhydrogencyclopolysiloxane, and dimethylsiloxane.・ Methylhydrogensiloxane cyclic copolymer, tris (dimethylhydrogensiloxy) methylsilane, tris (dimethylhydrogensiloxy) phenylsilane, molecular chain both ends trimethylsiloxy group blocked methylhydrogenpolysiloxane, molecular chain both ends trimethylsiloxy group Blocked dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain both ends trimethylsiloxy group blocked dimethylsiloxane / methylhydrogensiloxane / methylphenylsiloxane copolymer, molecular chain both ends dimethylhydride Logensiloxy group-blocked dimethylpolysiloxane, molecular chain both ends dimethylhydrogensiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain both ends dimethylhydrogensiloxy group-blocked dimethylsiloxane / methylphenylsiloxane copolymer, Methylphenylpolysiloxane blocked with dimethylhydrogensiloxy group blocked at both ends of the molecular chain, a siloxane unit represented by the formula: (CH ₃ ) ₂ HSiO _1/2 and a siloxane unit represented by the formula: (CH ₃ ) ₃ SiO _1/2 And a siloxane unit represented by the formula: SiO _4/2 , a siloxane unit represented by the formula: (CH ₃ ) ₂ HSiO _1/2 and a siloxane unit represented by the formula: SiO _4/2 A copolymer consisting of two or more of these organopolysiloxanes Mixtures thereof, and the like made.

Among them, (1) both ends of the molecular chain having no aliphatic unsaturated bond are represented by the formula: R ³ ₃ SiO _1/2 (wherein R ³ is independently as described above, and the same shall apply hereinafter). An organohydrogenpolysiloxane that is capped with a siloxane unit represented, and whose main chain is composed of repeating siloxane units represented by the formula: R ³ HSiO _2/2 , and (2) does not have an aliphatic unsaturated bond, Both ends of the molecular chain are independently blocked with a siloxane unit represented by the formula: R ³ ₃ SiO _1/2 or a siloxane unit represented by the formula: R ³ ₂ HSiO _1/2 , and the main chain is represented by the formula: R ³ ₂ siloxane units wherein represented by SiO ^_2/2: consisting random repetition of the siloxane units represented by R 3 _{HSiO 2/2,} and a diorganosiloxane-organohydrogensiloxane copolymer Those who use is preferable. Specifically, (1) molecular chain both ends trimethylsiloxy group-capped methylhydrogenpolysiloxane, and (2) dimethylsiloxane methylhydrogen having both molecular chain ends blocked with trimethylsiloxy group or dimethylhydrogensiloxy group. What used together with the siloxane copolymer is preferable.

  (B) The compounding quantity of a component is as follows. The composition of the present invention can contain a component having a silicon atom-bonded alkenyl group other than the component (A) and / or a component having a silicon atom-bonded hydrogen atom other than the component (B). Therefore, it is necessary that the amount of silicon atom-bonded hydrogen atoms in the composition is 1 to 7 mol, preferably 2 to 6 mol, relative to 1 mol of silicon atom-bonded alkenyl group in the composition. In particular, the amount of silicon atom-bonded hydrogen atoms in component (B) is 1 to 7 moles, especially 2 to 6 moles per mole of silicon-bonded alkenyl groups in component (A). It is. This is because when the silicon-bonded hydrogen atom is less than 1 mole relative to 1 mole of the silicon-bonded alkenyl group, sufficient strength of the coating film cannot be obtained. This is because the heat resistance and strength of the film are remarkably inferior. The ratio of the silicon atom-bonded alkenyl group in the component (A) to the total silicon atom-bonded alkenyl group in the composition is preferably 90 to 100 mol%, more preferably 95 to 100 mol%, particularly preferably 99. ~ 100 mol%. Further, the ratio of silicon atom-bonded hydrogen atoms in component (B) to all silicon-bonded hydrogen atoms in the composition is usually 90 to 100 mol%, preferably 95 to 100 mol%, particularly preferably 99 to 100 mol%.

  The (B) component organohydrogenpolysiloxane may be used alone or in combination of two or more.

-(C) Addition reaction catalyst-
The addition reaction catalyst for component (C) is a component for promoting / promoting the hydrosilylation reaction between the silicon atom-bonded alkenyl group in component (A) and the silicon atom-bonded hydrogen atom in component (B). The addition reaction catalyst is not particularly limited, and examples thereof include platinum group metals such as platinum, palladium and rhodium; chloroplatinic acid, alcohol-modified chloroplatinic acid, chloroplatinic acid and olefins, vinyl siloxane or acetylene compounds. Examples thereof include platinum group metal compounds such as coordination compounds, tetrakis (triphenylphosphine) palladium, chlorotris (triphenylphosphine) rhodium, and preferably platinum compounds.

  (C) The compounding quantity of a component should just be an effective amount as a catalyst, However, Usually, it is 0.1-1,000 in conversion of the mass of a platinum group metal with respect to the total amount of (A) component and (B) component. ppm, preferably 1 to 500 ppm, more preferably 10 to 100 ppm. When this blending amount is appropriate, the addition reaction can be promoted more effectively.

  (C) The addition reaction catalyst of a component may be used individually by 1 type, or may use 2 or more types together.

-(D) Gel process silica-
(D) Component Gel Method Silica is a component for reducing the sticky feeling peculiar to silicone rubber, improving the touch feeling, and creating a rubber-coated cloth excellent in workability and blocking resistance during sewing. . This gel method silica must have a BET specific surface area of 260 to 500 m ² / g and an average particle size of 0.5 to 20 μm. If the BET specific surface area is less than 260 m ² / g, the silicone rubber may remain sticky and the touch feeling may not be improved. If the BET specific surface area exceeds 500 m ² / g, the silicone rubber is resistant to blocking. It becomes inferior. In addition, when the average particle size is less than 0.5 μm, the silicone rubber is inferior in blocking resistance, and when it exceeds 20 μm, the feel of the silicone rubber may not be improved. Among them, the BET specific surface area is preferably 300 to 500 m ² / g, and more preferably 400 to 500 m ² / g. The average particle diameter is usually 1 to 20 μm, particularly preferably 5 to 18 μm, and more preferably 10 to 16 μm. The “average particle diameter” of the gel method silica means the cumulative weight average value D ₅₀ (or median diameter) of the silica by the gel method in the particle size distribution measurement by the laser light diffraction method.

  The gel method silica of this component may be a known one that has been conventionally used as a reinforcing filler for silicone rubbers, as long as the BET specific surface area and average particle diameter satisfy the above essential ranges. And fine powder silica. The fine powder silica may be used as it is, but the surface thereof is preferably subjected to a hydrophobic treatment with an organosilicon compound or the like. In addition, the manufacturing method of gel method silica is not specifically limited.

  Examples of organosilicon compounds used for surface hydrophobization of silica gel include silazanes such as hexamethyldisilazane; alkyls such as methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, and butyltrimethoxysilane Trialkoxysilanes; dialkyldialkoxysilanes such as dimethyldimethoxysilane and diethyldimethoxysilane; trialkylmonoalkoxysilanes such as trimethylmethoxysilane and triethylmethoxysilane; vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (methoxyethoxy) silane, Silane coupling agents such as trimethylchlorosilane, dimethyldichlorosilane, divinyldimethoxysilane and chloropropyltrimethoxysilane, polymethylsiloxane Emissions, organohydrogenpolysiloxane, and the like. These organosilicon compounds may be used alone or in combination of two or more.

  Further, when two or more kinds of organosilicon compounds are used in combination, two or more kinds may be mixed to perform surface hydrophobization treatment of the gel method silica, or two or more kinds may be divided and a part thereof may be divided. The surface may be subjected to surface hydrophobization treatment sequentially.

  The blending amount of component (D) is required to be 1 to 50 parts by mass with respect to 100 parts by mass of component (A), making the composition fluid and improving the workability and resistance of the cured product. Since blocking property can be made more excellent, it is preferably 1 to 10 parts by mass. If this blending amount exceeds 50 parts by mass, the fluidity of the composition may decrease, and the workability of the cured product may deteriorate. If this blending amount is less than 1 part by mass, silicone rubber In some cases, improvement in blocking resistance is not observed.

  (D) The gel method silica of a component may be used individually by 1 type, or may use 2 or more types together.

-(E) Adhesion improver-
(E) Adhesion improver used in the present invention is a cured product (rubber coating layer) for a synthetic fiber woven fabric base material, nonwoven fabric base material, thermoplastic resin sheet base material or film base material, etc. ) Is an ingredient for improving the adhesiveness. This adhesive improvement agent will not be specifically limited if it can improve the self-adhesiveness of hardened | cured material. Specific examples thereof include organic silicon compounds other than the components (A) and (B), non-silicon organic compounds, epoxy ring-opening catalysts, organic titanium compounds, etc. Among them, at least a functional group is contained in one molecule. What has 1 type is preferable, and what has 2 or more types is more preferable.

  Examples of the organic silicon compound include vinyl groups bonded to silicon atoms, alkenyl groups such as allyl groups; alkylene groups such as γ-glycidoxypropyl groups and β- (3,4-epoxycyclohexyl) ethyl groups. An epoxy group bonded to a silicon atom via a carbon atom; an acryloxy group or a methacryloxy group bonded to a silicon atom via a carbon atom such as an alkylene group such as a γ-acryloxypropyl group or γ-methacryloxypropyl group; An alkoxy group such as an ethoxy group, a propoxy group, or a butoxy group; a tri group bonded to a silicon atom via a carbon atom such as an alkylene group, which may have one or two ester structures, urethane structures, or ether structures; Alkoxysilyl groups such as methoxysilyl group, triethoxysilyl group, methyldimethoxysilyl group; And (silicon atom bond) at least one selected from the group consisting of hydrogen atoms, preferably organosilanes having two or more functional groups, 3 to 100 silicon atoms, preferably 3 to 50, more preferably Includes 5-20 linear or cyclic siloxane oligomers, triallyl isocyanurate (alkoxy) silyl modified products, siloxane derivatives thereof, etc. Among them, those having two or more functional groups in one molecule preferable. However, in the molecule, among the functional groups exemplified above, a siloxane oligomer having only a silicon atom-bonded alkenyl group and / or a silicon atom-bonded hydrogen atom and having an average of at least one of two or more (that is, (A ) Component or (B) component)).

  As a specific example of such an organosilicon compound,

（式中、ｎは１〜98の整数である。）

(In the formula, n is an integer of 1 to 98.)

等が挙げられる。

Etc.

  Examples of the non-silicon organic compound include organic acid allyl esters having one alkenyl group and at least one ester group in one molecule. Examples of organic acids include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and vinyl acetic acid; aromatic carboxylic acids such as benzoic acid, phthalic acid, and pyromellitic acid; acetic acid, propionic acid, butyric acid, valeric acid, lauric acid, and the like Of saturated fatty acids. Examples of organic acid allyl esters containing these organic acids include, for example, allyl esters such as unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and vinyl acetic acid; benzoic acid allyl ester, phthalic acid diallyl ester, pyromellitic acid tetraallyl ester, and the like. Aromatic carboxylic acid allyl esters of the following: saturated fatty acid allyl esters such as acetic acid allyl ester, propionic acid allyl ester, butyric acid allyl ester, valeric acid allyl ester, lauric acid allyl ester, and the like.

  The epoxy ring-opening catalyst has no silicon atom in the molecule, and examples thereof include epoxy ring-opening catalysts such as organometallic chelates, amines, amides, imidazoles, and acid anhydrides.

  The organic titanium compound does not have a silicon atom in the molecule. For example, tetrabutoxy titanium, tetrakis (2-ethylhexyloxy) titanium, tetrastearyloxy titanium, titanium stearate, tetraoctyloxy titanium, titanium isopropoxy Examples thereof include octylene glycolate, triethanolamine titanate, titanium acetylacetonate, titanium ethylacetonate, titanium lactonate, oligomers and polymers which are the condensation reaction products thereof.

  When the adhesion improver of this component is a compound having an epoxy group in the molecule as the functional group, the epoxy equivalent of the compound is preferably 100 to 5,000 g / mol, more preferably 150 to 3,000 g. / mol. When the epoxy equivalent satisfies this range, the composition has a good viscosity, and the cured product has better adhesiveness.

  Among the above-described adhesive improvers, the non-silicon organic compound having an epoxy equivalent of 100 to 5,000 g / mol, the organosilicon compound having an epoxy equivalent of 100 to 5,000 g / mol, and the epoxy equivalent of 100 to 5,000 g / mol epoxy ring-opening catalyst, silicon-bonded alkenyl group and / or organosilicon compound having at least one silicon-bonded hydrogen atom and silicon-bonded alkoxy group in each molecule, 12 or more carbon atoms These organic titanium compounds, organosilicon compounds containing one or more nitrogen atoms in one molecule, or combinations thereof are preferred.

  (E) The compounding quantity of a component needs to be 0.1-10 mass parts with respect to 100 mass parts of (A) component, Preferably it is 0.5-5 mass parts. If this blending amount is less than 0.1 parts by mass, the cured product may not have sufficient adhesiveness, and if this blending amount exceeds 10 parts by mass, the cost becomes high and uneconomical. It is.

  (E) The adhesive improvement agent of a component may be used individually by 1 type, or may use 2 or more types together.

-Optional component-
You may mix | blend the following components with the composition of this invention as needed other than the said (A)-(E) component. These optional components may be used alone or in combination of two or more.

Reaction control agent The reaction control agent is not particularly limited as long as it is a compound having an effect of adjusting the reaction rate of the curing reaction with respect to the addition reaction catalyst of the component (C), and a conventionally known one can also be used. . Specific examples thereof include phosphorus-containing compounds such as triphenylphosphine; compounds containing nitrogen atoms such as tributylamine, tetramethylethylenediamine, and benzotriazole; compounds containing sulfur atoms; acetylene-based compounds such as acetylene alcohols; Examples thereof include compounds containing 50 to 100 mol% of silicon atom-bonded alkenyl groups such as vinyl siloxane cyclics with respect to silicon atoms in the molecule; hydroperoxy compounds; maleic acid derivatives.

  The blending amount of the reaction control agent is preferably adjusted to an optimum amount for each reaction control agent to be used, because the degree of action of adjusting the reaction rate of the curing reaction of the reaction control agent varies depending on its chemical structure. By blending an optimal amount of the reaction control agent, the composition has excellent curability.

Inorganic filler Examples of the inorganic filler include crystalline silica, hollow filler, silsesquioxane, fumed titanium dioxide, magnesium oxide, zinc oxide, iron oxide, aluminum hydroxide, magnesium carbonate, calcium carbonate, zinc carbonate, Inorganic fillers such as layered mica, carbon black, diatomaceous earth, and glass fiber; inorganic fillers that have been surface-hydrophobized with organosilicon compounds such as organoalkoxysilane compounds, organochlorosilane compounds, organosilazane compounds, and low molecular weight siloxane compounds Agents; silicone rubber powder; silicone resin powder and the like. However, the inorganic filler is other than the component (D).

Other components As other components, for example, a linear diorgano having a silicon atom-bonded alkenyl group or silicon atom-bonded hydrogen atom at one end of the molecular chain and the other end blocked with a trialkylsiloxy group One silicon atom-bonded hydrogen atom or one silicon atom-bonded alkenyl group is contained in one molecule such as polysiloxane or linear diorganopolysiloxane in which both ends of the molecular chain are blocked with trialkylsiloxy groups. An organopolysiloxane having no other functional group; a non-reactive organopolysiloxane having no silicon-bonded hydrogen atom and silicon-bonded alkenyl group; an anti-creep hardening agent, a plasticizer, a thixotropic agent, and a pigment In order to improve the rubber strength of the cured product, such as dyes, fungicides, etc., for example, the formula: R ³ ₃ SiO _1/2 (wherein R ³ is the same as described above) and a siloxane unit represented by the formula: SiO _4/2 , containing or not containing an alkenyl group, a three-dimensional network-structured organopolysiloxane resin, etc. Can be blended.

  Furthermore, the composition of the present invention can be suitably used without blending an organic solvent. When coating the composition on various substrates, depending on conditions such as a coating apparatus, toluene, xylene, etc. The composition may be diluted to an arbitrary concentration with an organic solvent.

<Coating agent>
The composition of the present invention can be prepared by mixing the above components (A) to (E) and optionally optional components. The composition thus obtained is useful as a coating agent for fibers, particularly as a coating agent for airbags, particularly as a coating agent for bag-woven airbags.

  When used as a coating agent for an air bag, the composition is preferably liquid at room temperature (25 ° C.) and has a low viscosity. The viscosity is preferably 1,000 to 300,000 mPa · s, more preferably 20,000 to 90,000 mPa · s, and particularly preferably 30,000 to 80,000 mPa · s. When this viscosity satisfies such a range, not only the inflated state of the airbag lasts for a sufficient time, but also a good coating layer surface is obtained after coating of the composition. The above composition may be cured according to conventionally known curing methods and conditions, and can be usually performed by heating at 120 to 180 ° C. for 0.1 to 10 minutes.

<Airbag>
The airbag having a rubber coating layer made of a cured product of the composition of the present invention, preferably a bag-woven airbag, is not particularly limited, and conventionally known ones can be used. Specific examples thereof include synthetic fibers such as nylon 66, nylon 6, polyester fiber, aramid fiber, polyamide fiber, etc .; non-woven fabric base materials; airbags based on woven fabrics such as thermoplastic resin sheet or film base materials Etc.

A method for coating the air bag with the composition of the present invention is not particularly limited, and a conventional method can be adopted. The amount of the composition applied to the air bag (base fabric) surface to form the rubber coating layer is usually 10 to 150 g / m ² in a dry state, preferably 15 to 80 g / m ² , more preferably from 20 to 60 g / m ^2.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely using an Example, these Examples do not restrict | limit this invention at all. “Parts” means “parts by mass” and the viscosity is a measured value at 25 ° C. In addition, the adhesion improvers (i) to (iii) used in the examples have a structure represented by the following chemical formula.

・ Adhesion improver (i) [Epoxy equivalent: 238 g / mol]

・ Adhesion improver (ii)

・ Adhesion improver (iii)

[Example 1]
40 parts of dimethylpolysiloxane blocked with dimethylvinylsiloxy group at both ends of a molecular chain with a viscosity of 1,000 mPa · s, 40 parts of dimethylpolysiloxane blocked with dimethylvinylsiloxy group at both ends of a molecular chain with a viscosity of 5,000 mPa · s, diorganosiloxane as a main chain The unit contains 5 parts by mole of vinylmethylsiloxane units and 95 parts by mole of dimethylsiloxane units, and has a viscosity of 700 mPa · s, a trimethylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane copolymer with both ends of the molecular chain, 17 parts of hydrophobic silica surface-treated with trimethylsilyl groups and having a specific surface area of 120 m ² / g, trimethylsiloxy group-blocked methylhydrogenpolysiloxane with a viscosity of 50 mPa · s (content of silicon-bonded hydrogen atoms) = 1.45% by mass) 1.0 part, viscosity of 25mPa · s with molecular-bonded hydrogen atoms at both ends and non-end of molecular chain Dimethylsiloxane / methylhydrogensiloxane copolymer (content of silicon atom-bonded hydrogen atom = 0.54 mass%) 2.2 parts, 1-ethynylcyclohexanol 0.05 parts, platinum metal complex with chloroplatinic acid and divinyltetramethyldisiloxane 30 ppm with respect to the total amount of the component (A) and the component (B), 1.5 parts of the adhesion-imparting agent (i), 0.5 part of the adhesion-imparting agent (ii), 0.5 part of octyl titanate, and the ratio Composition 1 was prepared by uniformly mixing 10 parts of gel silica (trade name: NIPGEL BY-001, manufactured by Tosoh Silica Co., Ltd.) having a surface area of 450 m ² / g and an average particle diameter of 14 μm.

  In the composition 1, the silicon atom-bonded hydrogen atom (hereinafter referred to as “SiH / SiVi”) in the composition with respect to 1 mol of the silicon atom-bonded vinyl group in the composition was 3.9 mol.

  This composition 1 is cured at a temperature of 150 ° C. for 5 minutes, a sheet 1 is prepared according to JIS K6249, and general physical properties (hardness, tensile strength, elongation at shear, tear strength) are measured. According to the following measurement methods, peel adhesion, inflation, and blocking resistance were tested. The obtained results are shown in Table 1.

<Measurement method>
1. Peel adhesion test Between two nylon 66 (420 denier) fabrics for air bags, the composition prepared above was sandwiched so that the thickness in the dry state would be 0.5 mm, and 490 kN for 1 minute at 170 ° C. The composition was cured by applying a pressure of / m ² to form a rubber coating layer. Two nylon 66 fabrics bonded with this rubber coating layer are cut into a width of 2.5 cm and a length of 20 cm, and then each nylon 66 fabric is pulled at a speed of 50 mm / min in the direction of 180 degrees from the other. Thus, a peel adhesion test was performed.

2. Inflation Test The prepared composition was coated on a base of a bag-woven type air bag using a coater so that the coating composition was uniform and the amount of the composition used was minimized. Thereafter, the air bag was placed in an oven and cured by heating at 170 ° C. for 1 minute to produce a bag-woven air bag having a rubber coating layer. The air bag was inflated instantaneously by blowing air into the air bag at an air pressure of 690 kN / m ² for 3 seconds, and its airtightness was observed with the naked eye. A case where peeling is not recognized in the rubber coating layer is evaluated as “good” and indicated as “A”, and a case where peeling is recognized in the rubber coating layer is evaluated as “bad” and indicated as “B”.

3. Blocking resistance test This test was conducted to evaluate the stickiness of the surface of the rubber coating layer. A cloth with a rubber coating layer with a thickness of 0.2mm in a dry state on one side (film-forming cloth) is cut into a width of 100mm and a length of 200mm. Close contact was made. The glass plate to which this film-forming cloth was in close contact was set up vertically, the elapsed time until the film-forming cloth naturally dropped from the glass plate was measured, and evaluated according to the following evaluation criteria. As described above, when the elapsed time from the vertical standing of the glass plate to the time when the film-forming cloth fell from the glass plate was less than 3 seconds, it was evaluated as “good” and indicated as “A” for 3 seconds or more. When it is less than 10 seconds, it is evaluated as “somewhat good” and indicated as “B”, and when it is 10 seconds or more, it is evaluated as “bad” and indicated as “C”.

[Example 2]
40 parts of dimethylpolysiloxane blocked with dimethylvinylsiloxy group at both ends of a molecular chain with a viscosity of 1,000 mPa · s, 40 parts of dimethylpolysiloxane blocked with dimethylvinylsiloxy group at both ends of a molecular chain with a viscosity of 5,000 mPa · s, diorganosiloxane as a main chain The unit contains 10 parts by mole of vinylmethylsiloxane units and 90 parts by mole of dimethylsiloxane units, and 15 parts of a dimethylsiloxane / methylvinylsiloxane copolymer blocked with a trimethylsiloxy group at both ends of a molecular chain having a viscosity of 500 mPa · s, (CH _{3) 3} SiO _1/2 units 39.5 _{mol%, (CH 3) 2 (} CH 2 = CH) SiO 1/2 units 6.5 mol%, 5 parts of organopolysiloxane resin composed of SiO ₂ units 54 mol%, with trimethylsilyl group Hydrophobized 22 parts of hydrophobic silica with a specific surface area of 170 m ² / g, methyl chain-blocked methyl at both ends of the molecular chain with a viscosity of 45 mPa · s Hydrogenpolysiloxane (content of silicon-bonded hydrogen atoms = 1.14% by mass) 1.8 parts, dimethylsiloxane methylhydrogen having silicon-bonded hydrogen atoms at both molecular chain ends and molecular chain non-terminals with a viscosity of 12 mPa · s Siloxane copolymer (content of silicon atom-bonded hydrogen atom = 0.54% by mass) 5.3 parts, 0.03 part of 1-ethynylcyclohexanol, complex of chloroplatinic acid and divinyltetramethyldisiloxane in terms of platinum metal mass (A) 15 ppm, 1 part of adhesion promoter (i), 0.5 part of adhesion promoter (iii), 0.5 part of octyl titanate, and a specific surface area of 450 m ² / g with respect to the total amount of component and component (B) In addition, composition 2 was prepared by mixing 10 parts of gel method silica (manufactured by Tosoh Silica, trade name: NIPGEL BY-001) having an average particle size of 14 μm.

  In the above composition, SiH / SiVi was 3.4 mol.

  The general physical properties, peel adhesive strength, inflation, and blocking resistance of this composition 2 were tested and measured in the same manner as in Example 1. The obtained results are shown in Table 1.

[Comparative Example 1]
40 parts of dimethylpolysiloxane blocked with dimethylvinylsiloxy group at both ends of a molecular chain with a viscosity of 1,000 mPa · s, 40 parts of dimethylpolysiloxane blocked with dimethylvinylsiloxy group at both ends of a molecular chain with a viscosity of 5,000 mPa · s, diorganosiloxane as a main chain The unit contains 5 parts by mole of vinylmethylsiloxane units and 95 parts by mole of dimethylsiloxane units, and has a viscosity of 700 mPa · s, both ends of the molecular chain blocked trimethylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane copolymer 20 parts, trimethylsilyl group 17 parts of hydrophobic silica having a specific surface area of 120 m ² / g surface-hydrophobized with 1, a trimethylsiloxy group-blocked methylhydrogenpolysiloxane having a viscosity of 50 mPa · s (content of silicon-bonded hydrogen atoms = 1.45% by mass) 1.0 part, with a viscosity of 25 mPa · s. Dimethylsiloxane / methylhydrogensiloxane copolymer (content of silicon atom-bonded hydrogen atom = 0.54 mass%) 2.2 parts, 1-ethynylcyclohexanol 0.05 parts, platinum metal complex with chloroplatinic acid and divinyltetramethyldisiloxane 30 ppm with respect to the total amount of the component (A) and the component (B), 1.5 parts of the adhesion-imparting agent (i), 0.5 part of the adhesion-imparting agent (ii), 0.5 part of octyl titanate, and the ratio Composition C1 was prepared by mixing 10 parts of precipitated silica (made by Tosoh Silica, trade name: NIPSIL LP) having a surface area of 200 m ² / g and an average particle size of 8 μm.

  In the above composition, SiH / SiVi was 3.9 mol.

  The general physical properties, peel adhesive strength, inflation, and blocking resistance of this composition C1 were tested and measured in the same manner as in Example 1. The obtained results are shown in Table 1.

[Comparative Example 2]
100 parts of dimethylpolysiloxane blocked with a dimethylvinylsiloxy group at both ends of a molecular chain with a viscosity of 1,000 mPa · s, 33 parts of hydrophobic silica with a specific surface area of 170 m ² / g surface-hydrophobized with trimethylsilyl groups, and a viscosity of 45 mPa · s Methyl hydrogen polysiloxane blocked with trimethylsiloxy groups at both ends of the molecular chain (content of silicon atom-bonded hydrogen atoms = 1.14% by mass), 2.7 parts of viscosity with a viscosity of 12 mPa · s A dimethylsiloxane / methylhydrogensiloxane copolymer having atoms (content of silicon-bonded hydrogen atoms = 0.54% by mass) 8.3 parts, 1-ethynylcyclohexanol 0.06 parts, a complex of chloroplatinic acid and divinyltetramethyldisiloxane 15 ppm in terms of the mass of platinum metal with respect to the total amount of component (A) and component (B), adhesion promoter (i) 1.5 parts, adhesion promoter (ii) 0.5 , And by mixing 0.5 parts of octyl titanate, a composition was prepared C2.

  In the above composition, SiH / SiVi was 3.3 mol.

  The general physical properties, peel adhesive strength, inflation and blocking resistance of this composition C2 were tested and measured in the same manner as in Example 1. The obtained results are shown in Table 1.

<Evaluation>
As is clear from Table 1, in Examples 1 and 2 satisfying the requirements of claim 1, the obtained cured product (rubber coating layer) and airbag were excellent in all measured properties. On the other hand, in Comparative Examples 1 and 2 in which the gel method silica is not added or does not satisfy the requirements of claim 1, the cured product and the airbag have tensile strength, elongation at shear, tear strength, peel adhesive strength. At least one item of blocking resistance was inferior or the result of the inflation test was inferior.

Claims (4)

(A) Organopolysiloxane containing an alkenyl group bonded to at least two silicon atoms in one molecule: 100 parts by mass
(B) Organohydrogenpolysiloxane containing hydrogen atoms bonded to at least two silicon atoms in one molecule: silicon atoms in the composition with respect to 1 mol of alkenyl groups bonded to the silicon atoms in the composition An amount of 1 to 7 moles of hydrogen atoms bonded to
(C) addition reaction catalyst: effective amount,
(D) Gel method silica having a BET specific surface area of 260 to 500 m ² / g and an average particle size of 0.5 to 20 μm: 1 to 50 parts by mass, and (E) an adhesion improver: 0.1 to 10 parts by mass A liquid silicone rubber coating composition comprising:   The composition according to claim 1, which does not contain an organic solvent.   An air bag having a rubber coating layer made of a cured product of the composition according to claim 1. The airbag according to claim 3, wherein a bag portion is formed by weaving.