JP4648011B2 - Silicone adhesive composition containing no aromatic solvent and adhesive tape, sheet or label coated with the same - Google Patents

Description

  The present invention relates to a silicone pressure-sensitive adhesive composition containing no aromatic solvent and a pressure-sensitive adhesive tape, sheet or label coated with the same.

  Adhesive tapes and labels that use silicone adhesives are acrylic adhesives, rubber adhesives, etc., because the silicone adhesive layer has excellent heat resistance, cold resistance, weather resistance, electrical insulation and chemical resistance. Organic adhesives are used in harsh environments where they are altered or deteriorated. In addition, since it adheres well to various adherends, it is difficult to adhere with organic adhesives such as acrylic adhesives and rubber adhesives. Used for containing surfaces.

  For example, a pressure-sensitive adhesive tape using a silicone pressure-sensitive adhesive is used at the time of manufacturing and processing electronic / electrical parts and during assembly. When heat treatment is performed in this manufacturing process, it may be necessary to protect the entire surface or partially, masking or temporary fixing. Adhesive tapes used for such applications and adhesive tapes used in the manufacture, fixing, and binding of electronic and electrical parts exposed to high temperatures are made of silicone adhesive that has heat resistance even after heating above 250 ° C. Is preferred. However, in recent years, the process of manufacturing and processing electronic / electrical components has become multi-stage, and heating, cooling, cleaning, irradiation, and the like are repeated, and the precision and complexity of the electronic / electrical component are increasing. Furthermore, it is often processed in a closed space such as a clean room or clean booth for the purpose of dust-free.

However, MQ resin which is one of the raw materials of the silicone pressure-sensitive adhesive contains R ¹ ₃ SiO _0.5 unit and SiO ₂ unit, and the molar ratio of R ¹ ₃ SiO _0.5 unit / SiO ₂ unit is 0.00. It consists of a polyorganosiloxane (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) that is 6 to 1.7, and is produced in a reaction system using toluene or xylene as a solvent. Since this polyorganosiloxane becomes a solid when the solvent is removed, it is industrially handled as a toluene or xylene solution. Also when manufacturing a silicone adhesive, since MQ resin is used as solutions, such as toluene or xylene, a conventionally well-known silicone adhesive composition contains these aromatic solvents.

  To produce an adhesive tape, sheet or level, a silicone adhesive composition is applied to a substrate such as a plastic film and cured by heating to form an adhesive layer. When the produced silicone pressure-sensitive adhesive composition was used, it was inevitable that a trace amount of aromatic solvent remained in the pressure-sensitive adhesive layer even after the heating step.

  Therefore, when sticking or masking an adhesive tape or adhesive label using these silicone adhesives on an adherend and receiving a high temperature history of 100 to 250 ° C., a trace amount of toluene, xylene, Aromatic hydrocarbons such as ethylbenzene and benzene may volatilize. These aromatic hydrocarbons are contained in the silicone pressure-sensitive adhesive composition. In a closed space in the manufacturing process of electrical / electronic parts as described above, adhesive tape using silicone adhesive is used to generate volatile substances of aromatic hydrocarbons, and UV irradiation is performed in subsequent processes. When performed, ultraviolet rays are absorbed by aromatic hydrocarbons, which may cause a problem that irradiation is not performed efficiently.

  In addition, in the use of adhesive tapes and labels for construction, interiors, etc., the surface of the adherend contains silicone resin or fluorine resin for the purpose of water repellency, oil repellency, dirt prevention, etc. A silicone adhesive may be used because it may be fluorinated. Adhesive paper for wallpaper, adhesive paper for decorative boards such as furniture, adhesive tape for waterproofing and airtightness, adhesive tape for fixing indoor interior, repair tape, decorative fixing tape, adhesive film for preventing glass scattering, adhesive for light shielding In adhesive tapes and adhesive labels used in living environments such as films and tapes for fixing automobile interiors, if aromatic hydrocarbon solvent remains, volatilizes, and stays in indoor air, it is extremely small. However, it may cause chemical allergy, sick house syndrome, chemical sensitivity, etc.

  Furthermore, in applications such as adhesives, adhesive bandages, surgical tapes, sports taping tapes, etc. that are applied directly to the skin, irritation to the skin becomes a problem if aromatic hydrocarbon solvent remains.

  The present invention is an improvement of the above circumstances, and does not contain aromatic hydrocarbon solvent, and can prevent contamination of electronic and electrical parts, effects on the human body, and irritation to the skin due to substances that remain or volatilize. It is an object to provide a simple silicone pressure-sensitive adhesive composition.

Japanese Patent Publication No. 30-5186 Japanese Patent Publication No.32-5099

As a result of intensive studies, the present inventor contains R ¹ ₃ SiO _0.5 unit and SiO ₂ unit produced without using an aromatic hydrocarbon solvent, and R ¹ ₃ SiO _0.5 unit / SiO 2 _It has been found that a silicone pressure-sensitive adhesive composition produced using a polyorganosiloxane having a molar ratio of ₂ units of 0.6 to 1.7 is effective in achieving the above object.
The silicone pressure-sensitive adhesive composition of the present invention may be either an organic peroxide curable type or an addition reaction curable type.

As the peroxide curable silicone pressure-sensitive adhesive composition, the following are used.
(A) Polydiorganosiloxane 20 to 80 parts by mass (B) R ¹ ₃ SiO _0.5 units and SiO ₂ units are contained, and the molar ratio of R ¹ ₃ SiO _0.5 units / SiO ₂ units is 0.6 to Polyorganosiloxane which is 1.7 (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) 80 to 20 parts by mass (C) Organic peroxide curing agent (A), (B) total 100 masses 0.5 to 5.0 parts by weight with respect to parts (D) Aliphatic organic solvent (A), consisting of 25 to 900 parts by weight with respect to a total of 100 parts by weight of (B). A peroxide-curable silicone pressure-sensitive adhesive composition, which is produced without using a group hydrocarbon solvent.

The following are used as the addition reaction curable silicone pressure-sensitive adhesive composition.
(A ′) 20 to 80 parts by mass of a polydiorganosiloxane having two or more alkenyl groups in one molecule (B) containing R ¹ ₃ SiO _0.5 units and SiO ₂ units, and R ¹ ₃ SiO _0.5 Polyorganosiloxane having a unit / SiO ₂ unit molar ratio of 0.6 to 1.7 (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) 80 to 20 parts by mass (E) containing SiH groups Polyorganosiloxane (A ') Amount in which the molar ratio of SiH groups in component (E) to alkenyl groups in component (A) is 0.5-20 (F) Control agent (A'), total of (B) 100 0 to 8.0 parts by mass with respect to parts by mass (G) Platinum catalyst (A ′), 5 to 2000 ppm as platinum content with respect to the total of components (B)
(D) Aliphatic organic solvent (A ') Consisting of 25 to 900 parts by mass with respect to 100 parts by mass of (B), the component (B) was produced without using an aromatic hydrocarbon solvent An addition reaction type silicone pressure-sensitive adhesive composition is provided.

According to the present invention, a silicone pressure-sensitive adhesive composition containing no aromatic solvent can be obtained.
In this case, these silicone pressure-sensitive adhesive compositions are effectively used for excellent pressure-sensitive adhesive tapes, pressure-sensitive adhesive sheets, pressure-sensitive adhesive labels, and the like.

Peroxide-curing silicone pressure-sensitive adhesive composition Hereinafter, in more detail, the component (A) used as the peroxide-curing silicone pressure-sensitive adhesive composition is polydiorganosiloxane, and is represented by the following formula: . Those represented by Chemical Formula 2 wherein the molecular chain terminal is an OH group are preferred.

（式中、Ｒ^２は同一または異種の炭素数１から１０の炭化水素基。ｐはこのポリジオルガノシロキサンの２５℃における粘度を５００ｍＰａ・ｓ以上とする数である。）

(In the formula, R ² is the same or different hydrocarbon group having 1 to 10 carbon atoms. P is a number that makes this polydiorganosiloxane have a viscosity at 25 ° C. of 500 mPa · s or more.)

Here, as R ² , a monovalent hydrocarbon group having 1 to 10 carbon atoms is preferable. For example, an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group, a cycloalkyl group such as a cyclohexyl group, phenyl Groups, aryl groups such as tolyl groups, alkenyl groups such as vinyl groups, allyl groups, and hexenyl groups, and some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with other groups. And 3-aminopropyl group, 3,3,3-trifluoropropyl group, 3-hydroxypropyl group, and the like. A methyl group and a phenyl group are particularly preferable.

  The polydiorganosiloxane may be in the form of oil or raw rubber. The viscosity of the component (A) is at least 500 mPa · s if it is oily at 25 ° C. In particular, 10,000 mPa · s or more is preferable. If it is 500 mPa · s or less, the curability is lowered or the cohesive force (holding force) is lowered, which is not suitable. Moreover, if it is a raw rubber-like thing, the viscosity when it melt | dissolves with toluene so that it may become a 30% density | concentration is preferable 100,000 mPa * s or less. If it exceeds 100,000 mPa · s, the composition becomes too viscous and stirring during production becomes difficult. Furthermore, (A) component may use 2 or more types together.

  The component (A) is usually produced by subjecting a monomer such as octamethylcyclotetrasiloxane to ring-opening polymerization using a catalyst. Since the polymer contains a cyclic low-molecular siloxane after polymerization, It is preferable to use a product obtained by distilling siloxane while heating and / or aerated with an inert gas under reduced pressure.

The component (B) contains R ¹ ₃ SiO _0.5 units (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) and SiO ₂ units, and R ¹ ₃ SiO _0.5 units / SiO ₂ A polyorganosiloxane having a unit molar ratio of 0.6 to 1.7, more preferably 0.7 to 0.9. If the molar ratio of R ¹ ₃ SiO _0.5 unit / SiO ₂ unit is less than 0.6, the adhesive strength and tack may be reduced, and if it exceeds 1.7, the adhesive strength and holding power may be reduced. Examples of R ¹ include an alkyl group such as a methyl group, an ethyl group, a propyl group, and a butyl group, a cycloalkyl group, a phenyl group, a vinyl group, an allyl group, and a hexenyl group. Furthermore, some or all of hydrogen atoms bonded to carbon atoms of these groups are substituted with other groups, such as 3-aminopropyl group, 3,3,3-trifluoropropyl group, 3-hydroxypropyl group, etc. Are also illustrated. A methyl group is preferred.

The component (B) may contain OH groups, and the OH group content is preferably 0.01 to 4.0% by mass. When the OH group is less than 0.01% by mass, the cohesive force of the pressure-sensitive adhesive may be lowered, and when it exceeds 4.0% by mass, the tackiness of the pressure-sensitive adhesive is not preferable. It is also possible to within a range that does not impair the characteristics of the present invention contains ^R 1 _{SiO 1.5} ^units, a _R 1 2 SiO units (B) component. In addition, (B) component may use 2 or more types together.

The component (B) used in the present invention is produced without using an aromatic solvent.
The production method includes, for example, (a) a step of forming a hydrosol in the presence of an acid in a solvent containing sodium silicate in water, and a step of reacting the hydrosol with a triorganohalosilane, (B) a method comprising a step of adding sodium silicate into a mixed system containing a triorganohalosilane and an acid, (c) the presence of an acid and water, tetraalkoxysilane and / or a hydrolyzate thereof, and hexaorganodisiloxane. Any method including the step of reacting below is possible.

  Further, the method (a) will be described in detail. US Pat. Nos. 2,676,182 and 2,814,601 are known methods. That is, after forming a hydrosol in the presence of an acid in a solvent containing sodium silicate in water, the alcohol is added to stabilize the hydrosol, and then the hydrosol and the triorganohalosilane are reacted. It is preferable to include a step of adding an aliphatic hydrocarbon solvent. Furthermore, after completion of the reaction, the organic layer containing the desired organopolysiloxane and the aqueous layer are separated, and if necessary, the alcohol and acid remaining in the organic layer are removed by washing and / or neutralized with a base. It is preferable to include it. Furthermore, if necessary, a step of adding a non-aromatic solvent or the like may be added to adjust the concentration of organopolysiloxane, dehydration of residual water, condensation with a base catalyst, or organopolysiloxane.

  Further, the method (b) will be described in detail. That is, a step of adding an oxygen-containing solvent having a solubility in water at room temperature of 1 to 100 to a mixed system containing triorganohalosilane and an acid, and further adding a mixture of sodium silicate and water and reacting them. It is preferable to include. Furthermore, after completion of the reaction, the organic layer containing the desired organopolysiloxane and the aqueous layer are separated, and if necessary, the alcohol and acid remaining in the organic layer are removed by washing and / or neutralized with a base. It is preferable to include it. Furthermore, if necessary, a step of adding a non-aromatic solvent or the like may be added to adjust the concentration of organopolysiloxane, dehydration of residual water, condensation with a base catalyst, or organopolysiloxane.

  Further, the method (c) is described in detail in JP-A 61-195129, JP-B-6-23253 and JP-B-6-33335. That is, it is preferable to include a step of reacting tetraalkoxysilane and / or its hydrolyzate with hexaorganodisiloxane by adding acid and water. Furthermore, after completion of the reaction, the organic layer containing the desired organopolysiloxane and the aqueous layer are separated, and if necessary, the alcohol and acid remaining in the organic layer are removed by washing and / or neutralized with a base. It is preferable to include it. Furthermore, if necessary, a step of adding a non-aromatic solvent or the like may be added to adjust the concentration of organopolysiloxane, dehydration of residual water, condensation with a base catalyst, or organopolysiloxane.

  The mixing ratio of the components (A) and (B) is preferably 20/80 to 80/20, particularly 30/70 to 70/30 as a mass ratio. When the blending ratio of the polydiorganosiloxane as the component (A) is lower than 20/80, the adhesive strength and holding power decrease, and when it exceeds 80/20, the adhesive strength and tack decrease.

  Component (C) is an organic peroxide curing agent, specifically dibenzoyl peroxide, 4,4′-dimethyldibenzoyl peroxide, 3,3′-dimethyldibenzoyl peroxide, 2,2′-dimethyl. Examples include dibenzoyl peroxide, 2, 2 ′, 4, 4′-tetrachlorodibenzoyl peroxide, cumyl peroxide, and the like.

  (C) The compounding quantity of a component should just be the range of 0.5-5 mass parts with respect to a total of 100 mass parts of a component (A) and (B). 1 to 4 parts by mass is particularly preferable. If it is less than 0.5 part by mass, curability and holding power may be lowered. If it exceeds 5 parts by mass, the pressure-sensitive adhesive layer may be colored or the adhesive strength may be reduced. The form of (C) component is not specifically limited. Examples thereof include (C) component alone, (C) component diluted in an organic solvent, dispersed in water, and dispersed in silicone oil or the like to form a paste. (C) 2 or more types may be used together.

  Component (D) is an aliphatic organic solvent other than an aromatic hydrocarbon solvent, and examples thereof include those that uniformly dissolve the components (A) to (C) described above. Specifically, aliphatic hydrocarbon solvents such as hexane, heptane, octane, isooctane, decane, cyclohexane, methylcyclohexane, isoparaffin, acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 2-heptanone, Ketone solvents such as 4-heptanone, methyl isobutyl ketone, diisobutyl ketone, acetonyl acetone, cyclohexanone,

Ethyl formate, propyl formate, butyl formate, isobutyl formate, pentyl formate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, pentyl acetate, isopentyl acetate, 3-methoxybutyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, cyclohexyl acetate, methyl propionate, ethyl propionate, butyl propionate, isopentyl propionate, ethyl butyrate, butyl butyrate, butyl isobutyrate, γ-butyrolactone, diethyl oxalate, ethylene glycol monoacetate, ethylene Glycol monoesters, ethylene glycol diesters, diethylene glycol monoesters, diethylene glycol diesters, diethyl carbonate, ethylene carbonate, propylene carbonate, etc. Le-based solvents,

Diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, 1,2-dimethoxyethane, 1,2-diethoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol dimethyl ether, acetal, 1,4-dioxane Ether solvents such as

Alcohol solvents such as methanol, ethanol, isopropanol, butanol and isobutanol, nitrile solvents such as acetonitrile and propionitrile, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N Amide solvents such as dimethylacetamide, 2-pyrrolidone, N-methylpyrrolidone,

Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono Ethyl ether, dipropylene glycol monobutyl ether, diacetone alcohol, methyl lactate, ethyl lactate, 2-methoxyethyl acetate, 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, 2-butoxyethyl acetate, diethylene glycol monoethyl Ethereal Acetate, diethylene glycol monobutyl ether acetate, methyl acetoacetate, multi-functional solvent ethyl acetoacetate, etc.,

Siloxane solvents such as hexamethyldisiloxane, octamethyltrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, tris (trimethylsiloxy) methylsilane, tetrakis (trimethylsiloxy) silane,

Or these mixed solvents are mentioned. Does not contain aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene and styrene. Furthermore, aliphatic hydrocarbon solvents such as hexane, heptane, isooctane, octane, decane, cyclohexane, methylcyclohexane, and isoparaffin, which do not contain halogen solvents such as dichloromethane, chloroform, carbon tetrachloride, trichloroethane, bromoform, and chlorofluorocarbons are preferable. . A mixed solvent of an aliphatic hydrocarbon solvent and an ether solvent, an ester solvent, a solvent having both an ether group and an ester group, or the like is also preferable.

  The composition of the present invention is produced by mixing and dissolving a part or all of the component (A), the component (B), and the component (D). Usually, the concentration of the nonvolatile content is adjusted to, for example, 30 to 80% by mass, and the container is filled for storage and transportation. When manufacturing pressure-sensitive adhesive tapes, pressure-sensitive adhesive sheets, pressure-sensitive adhesive labels, etc., these are diluted with an organic solvent as necessary, and component (C) is added and mixed to be applied to various substrates shown later. The

  Alternatively, it is produced by mixing a part or all of the component (A), the component (B), and the component (D) in the presence of a base catalyst at room temperature or under heating. Base catalysts include metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide and calcium hydroxide, carbonates such as sodium carbonate and potassium carbonate, bicarbonates such as sodium bicarbonate, sodium methoxide And metal alkoxides such as potassium butoxide, organic metals such as butyl lithium, potassium silanolates, ammonia gas, aqueous ammonia, nitrogen compounds such as methylamine, trimethylamine, and triethylamine. Ammonia gas and aqueous ammonia are preferred. The temperature can be 20-150 ° C. Usually, it may be carried out at room temperature or the reflux temperature of an organic solvent. The time is not particularly limited, but may be 0.5 to 10 hours, preferably 1 to 6 hours.

  Furthermore, a neutralizing agent that neutralizes the base catalyst may be added as necessary after completion of the reaction. Examples of the neutralizing agent include acidic gases such as hydrogen chloride and carbon dioxide, organic acids such as acetic acid, octylic acid, and citric acid, and mineral acids such as hydrochloric acid, sulfuric acid, and phosphoric acid.

  This product is usually filled into containers for storage and transportation. When manufacturing adhesive tapes, adhesive sheets, adhesive labels, etc., this product is diluted with an organic solvent as necessary, and component (C) is added and mixed, and then applied to various substrates shown below. Is done.

  Regardless of the method as described above, for example, the pressure-sensitive adhesive tape produced using the silicone pressure-sensitive adhesive composition produced using the component (B) produced using a conventional aromatic solvent contains an aromatic solvent. The residue cannot be eliminated. In addition, the solvent is removed from the component (B) produced using an aromatic solvent by a method such as heating and decompression, and a silicone pressure-sensitive adhesive composition is produced using this, but even in this case, It is inevitable that a trace amount of aromatic solvent remains.

Addition reaction curable silicone pressure-sensitive adhesive composition The component (A ′) used as the addition reaction curable silicone pressure-sensitive adhesive composition is an alkenyl group-containing polydiorganosiloxane, and is preferably represented by the following formula.

（式中、Ｒ^３は脂肪属不飽和結合を有さない１価炭化水素基、Ｒ^４はアルケニル基含有有機基であり、ａは０〜３の整数、好ましくは１、ｍは０以上、ｎは１００以上の整数であり、ａが０のときｍは２以上。また、ｍ＋ｎはこのポリジオルガノシロキサンの２５℃における粘度を５００ ｍＰａ・ｓ以上とする数である。）

(In the formula, R ³ is a monovalent hydrocarbon group having no aliphatic unsaturated bond, R ⁴ is an alkenyl group-containing organic group, a is an integer of 0 to 3, preferably 1, m is 0 or more, n is an integer of 100 or more, and when a is 0, m is 2 or more, and m + n is a number that makes this polydiorganosiloxane have a viscosity at 25 ° C. of 500 mPa · s or more.)

Here, R ³ preferably has 1 to 10 carbon atoms. For example, alkyl groups such as methyl group, ethyl group, propyl group and butyl group, cycloalkyl groups such as cyclohexyl group, phenyl group and tolyl group A 3-aminopropyl group, a 3,3,3-trifluoropropyl group, etc., wherein a part or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with other groups And a 3-hydroxypropyl group. A methyl group and a phenyl group are particularly preferable.

The alkenyl group-containing organic group represented by R ⁴ is preferably an organic group having 2 to 10 carbon atoms, such as vinyl group, allyl group, hexenyl group, octenyl group, acryloylpropyl group, acryloylmethyl group, methacryloylpropyl group, cyclohexenylethyl group, A vinyloxypropyl group and the like, and a vinyl group is particularly preferred industrially.

The polydiorganosiloxane may be in the form of oil or raw rubber.
The viscosity of the component (A ′) is at least 500 mPa · s if it is oily at 25 ° C. In particular, 10,000 mPa · s or more is preferable. If it is 500 mPa · s or less, the adhesive strength and tack decrease, which is not suitable. Moreover, if it is a raw rubber-like thing, the viscosity when it melt | dissolves with toluene so that it may become a density | concentration of 30% is preferable below 100,000 mPa * s. If it exceeds 100,000 mPa · s, the composition becomes too viscous and stirring during production becomes difficult. Furthermore, two or more kinds of the component (A ′) may be used in combination.

  The component (A ′) is usually produced by ring-opening polymerization of a monomer such as octamethylcyclotetrasiloxane using a catalyst. After the polymerization, the cyclic low molecular weight siloxane is contained. It is preferable to use molecular siloxane distilled off while heating and reducing pressure while allowing an inert gas to pass through.

As described above, the component (B) contains R ¹ ₃ SiO _0.5 units and SiO ₂ units, and the molar ratio of R ¹ ₃ SiO _0.5 units / SiO ₂ units is 0.6 to 1.7, A polyorganosiloxane (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) which is preferably 0.7 to 0.9.

(B) 2 or more types of components may be used together. It is also possible to within a range that does not impair the characteristics of the present invention contains ^R 1 _{SiO 1.5} ^units, a _R 1 2 SiO units (B) component.

  The blending ratio of the components (A ′) and (B) may be 20/80 to 80/20. In particular, the ratio is preferably 30/70 to 70/30. When the blending ratio of the polydiorganosiloxane as the component (A ′) is lower than 20/80, the adhesive strength and holding power decrease, and when it exceeds 80/20, the adhesive strength and tack decrease.

  Component (E) is a crosslinking agent, which is an organohydropolysiloxane having at least 2, preferably 3 or more hydrogen atoms bonded to silicon atoms in one molecule, and uses linear, branched, or cyclic ones. it can.

  (E) As a component, the thing of a following formula can be illustrated, However, It is not limited to these.

及び／または

And / or

（Ｒ^５は同一または異種の脂肪属不飽和結合を有さない１価炭化水素基であり、ｂは０または１、ｘ、ｙは０以上の整数。ｂが０のときは、ｘは２以上であり、このオルガノヒドロポリシロキサンの２５℃における粘度が１〜５，０００ｍＰａ・ｓとなる数を示す。また、ｓは２以上の整数、ｔは０以上の整数で、かつｓ＋ｔ≧３、好ましくは８≧ｓ＋ｔ≧３の整数を示す。）

(R ⁵ is a monovalent hydrocarbon group not having the same or different aliphatic unsaturated bond, b is 0 or 1, x and y are integers of 0 or more. When b is 0, x is 2 These are the numbers at which the viscosity of this organohydropolysiloxane at 25 ° C. is 1 to 5,000 mPa · s, s is an integer of 2 or more, t is an integer of 0 or more, and s + t ≧ 3, (It preferably represents an integer of 8 ≧ s + t ≧ 3.)

Here, R ⁵ is a monovalent hydrocarbon group having 1 to 10 carbon atoms, specifically, an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group, a cycloalkyl group such as a cyclohexyl group, a phenyl group, An aryl group such as a tolyl group, and the like, and a 3-aminopropyl group, 3,3,3-trifluoro, wherein some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with other groups A propyl group, a 3-hydroxypropyl group, and the like are also exemplified. A methyl group and a phenyl group are particularly preferable.

  The viscosity of this organohydropolysiloxane at 25 ° C. is preferably 1 to 5,000 mPa · s, more preferably 5 to 500 mPa · s. A mixture of two or more kinds may be used.

  Component (E) is used in such an amount that the molar ratio of SiH groups in component (E) to alkenyl groups in component (A ′) is in the range of 0.5 to 20, particularly 0.8 to 15. It is preferable. If it is less than 0.5, the crosslinking density is lowered, and the holding power may be lowered accordingly, and if it exceeds 20, the crosslinking density is increased and sufficient adhesive strength and tack may not be obtained.

  Component (F) is a control agent, and is added to prevent the treatment liquid from thickening or gelling before heat-curing when the silicone adhesive composition is prepared or applied to the substrate. It is. Specific examples include 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 1-ethynylcyclohexanol, 3 -Methyl-3-trimethylsiloxy-1-butyne, 3-methyl-3-trimethylsiloxy-1-pentyne, 3,5-dimethyl-3-trimethylsiloxy-1-hexyne, 1-ethynyl-1-trimethylsiloxycyclohexane, Bis (2,2-dimethyl-3-butynoxy) dimethylsilane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, 1,1,3,3-tetramethyl -1,3-divinyldisiloxane and the like.

  The blending amount of the component (F) may be in the range of 0 to 8.0 parts by mass, particularly 0.05 to 2.0 parts by mass with respect to 100 parts by mass in total of the components (A ′) and (B). Is preferred. If it exceeds 8.0 parts by mass, curability may be lowered.

  Component (G) is an addition reaction catalyst, containing chloroplatinic acid, an alcohol solution of chloroplatinic acid, a reaction product of chloroplatinic acid and alcohol, a reaction product of chloroplatinic acid and an olefin compound, and containing chloroplatinic acid and a vinyl group Examples thereof include a reaction product with siloxane, a platinum-olefin complex, a platinum-vinyl group-containing siloxane complex, a rhodium complex, and a ruthenium complex.

  The addition amount is preferably 5 to 2,000 ppm, particularly 10 to 500 ppm in terms of metal content with respect to the total of components (A ′) and (B). If it is less than 5 ppm, the curability is lowered, the crosslinking density is lowered and the holding power may be lowered, and if it exceeds 2,000 ppm, the usable time of the treatment bath may be shortened.

  The composition of the present invention is produced by mixing and dissolving the components (A ′), (B), (D), (E), and (F). Usually, the concentration of the nonvolatile content is adjusted to, for example, 30 to 80% by mass, and the container is filled for storage and transportation. When manufacturing adhesive tapes, adhesive sheets, adhesive labels, etc., this is diluted with an organic solvent as necessary, and the component (G) is added and mixed to be applied to various substrates shown later. The

  Alternatively, in the composition of the present invention, the components (A ′), (B), and (D) are mixed with a part or all of the components in the presence of a base catalyst, and the components (E) and (F) are added. It is manufactured by adding. The base catalyst is the same as described above. Although the temperature of mixing can be 20-150 degreeC, what is necessary is just to carry out normally at the reflux temperature of room temperature-the organic solvent. The time is not particularly limited, but may be 0.5 to 10 hours, preferably 1 to 6 hours.

  Furthermore, a neutralizing agent that neutralizes the base catalyst may be added as necessary after completion of the reaction. The neutralizing agent is the same as described above.

  This product is usually filled in a container for storage and transportation by adjusting the concentration of non-volatile components to, for example, 30 to 80% by mass. When manufacturing adhesive tapes, adhesive sheets, adhesive labels, etc., dilute the product with an organic solvent as necessary, add and mix component (G), and apply to various substrates shown below. Is done.

Other Additives In addition to the above components, optional components can be added to the silicone pressure-sensitive adhesive composition of the present invention. For example, polyorganosiloxanes such as polydimethylsiloxane and polydimethyldiphenylsiloxane, antioxidants such as phenol, quinone, amine, phosphorus, phosphite, sulfur, thioether, hindered amine, and triazole , Benzophenone-based light stabilizers, phosphate ester-based, halogen-based, phosphorus-based, antimony-based flame retardants, cationic surfactants, anionic surfactants, non-ionic surfactants and other antistatic agents, when coating Solvents for reducing the viscosity of the solvent include aliphatic hydrocarbon solvents such as hexane, octane and isoparaffin, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate and isobutyl acetate, diisopropyl ether, 1, Aether such as 4-dioxane System solvent or solvent mixture thereof, dyes, such as pigments are used.

The silicone pressure-sensitive adhesive composition formulated as described above can be applied to various substrates and cured under predetermined conditions to obtain a pressure-sensitive adhesive layer.
As the base material, polyester, polytetrafluoroethylene, polyimide, polyphenylene sulfide, polyamide, polycarbonate, polystyrene, polypropylene, polyethylene, polyvinyl chloride and other metal films, aluminum foil, copper foil and other metal foil, Japanese paper, synthetic paper, Examples thereof include paper such as polyethylene laminated paper, cloth, glass fiber, and a composite base material formed by laminating a plurality of these.

  In order to improve the adhesion between the base material and the adhesive layer, a primer-treated, corona-treated, etched, plasma-treated, or sand-blasted material may be used.

The coating method may be applied using a known coating method, comma coater, lip coater, roll coater, die coater, knife coater, blade coater, rod coater, kiss coater, gravure coater, screen coating, dipping. Examples thereof include coating and cast coating.
The coating amount can be 2 to 200 μm, particularly 3 to 100 μm, as the thickness of the adhesive layer after curing.

  As curing conditions, the peroxide curing type may be 100 to 200 ° C. for 30 seconds to 10 minutes, and the addition reaction type may be 80 to 130 ° C. for 30 seconds to 3 minutes, but is not limited thereto. .

  As described above, it may be applied directly to a base material to produce an adhesive tape, a sheet, a label, etc., or after applied to a release film or release paper subjected to release coating and cured, You may manufacture an adhesive tape, a sheet | seat, a label, etc. with the transfer method bonded on a base material.

  Although it does not specifically limit as an adherend which can be masked with the adhesive tape, sheet | seat, label, etc. which were manufactured using the silicone adhesive composition of this invention, The following can be illustrated. Metals and alloys such as stainless steel, copper, iron, aluminum, chromium, gold, etc., metal whose surface is plated or rust-proofed, coated, glass, ceramics, ceramics, polytetrafluoroethylene, polyimide, epoxy resin, A resin such as a novolac resin or a composite of a plurality of these resins.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In addition, the part in an example shows the mass part, and a characteristic value shows the measured value by the following test method. Me represents a methyl group and Vi represents a vinyl group.

After the adhesive silicone adhesive composition solution was applied to a polyimide film having a thickness of 25 μm and a width of 25 mm using an applicator so that the thickness after curing was 40 μm, the peroxide curing type was 165 ° C. The additional type was heated and cured at 120 ° C. for 1 minute for 2 minutes to prepare an adhesive tape. This adhesive tape was affixed to a stainless steel plate and pressed by reciprocating a roller covered with a rubber layer having a weight of 2 kg. After standing at room temperature for about 20 hours, the force (N / 25 mm) required to peel the tape from the stainless steel plate at an angle of 180 ° at a speed of 300 mm / min was measured using a tensile tester.

A pressure-sensitive adhesive tape was prepared in the same manner as in the evaluation of the holding power and the adhesive strength. The adhesive tape is affixed to the lower end of the stainless steel plate so that the adhesive area is 25 × 25 mm, a weight of 1 kg is applied to the lower end of the adhesive tape, and the deviation distance after standing vertically at 250 ° C. for 1 hour is determined. Reading was measured with a microscope.

An adhesive tape was prepared in the same manner as in the probe tack adhesion evaluation. The tack of this adhesive tape was measured using a Polyken probe tack tester.

A pressure-sensitive adhesive tape was prepared in the same manner as in the evaluation of residual toluene amount adhesive strength. About 10 cm of this adhesive tape was weighed and then sealed in a vial. After the vial was heated at 260 ° C. for 1 hour, the amount of toluene generated per unit adhesive tape mass was quantified by analyzing the gas in the vial by gas chromatography.

[Synthesis Example 1]
To a mixture of 36% hydrochloric acid (202 parts) and water (794 parts), a mixture of sodium silicate (sodium silicate 3) (480 parts) and water (268 parts) was added dropwise while maintaining the temperature at 0 to 10 ° C. A hydrosol was formed. Then, after adding isopropanol (527 parts), a mixture of trimethylchlorosilane (317 parts) and isoparaffin (boiling range 115 to 138 ° C.) (366 parts) was added dropwise while maintaining 15 ° C. Then, it heated at 60 degreeC for 30 minutes. After allowing to stand and separating, the lower aqueous layer was discarded. Sodium bicarbonate was added to the organic layer to neutralize excess acid. After azeotropic dehydration, isoparaffin was added so that the nonvolatile content of the solution layer was 60%. Insoluble matter was removed by filtration to obtain an isoparaffin solution of polysiloxane I containing _0.5 units of Me ₃ SiO and ₂ units of SiO _{2 in} a yield of 78%. The molar ratio of Me ₃ SiO _0.5 unit / SiO ₂ unit was 0.85.

[Synthesis Example 2]
In a mixture of trimethylchlorosilane (266 parts), 36% hydrochloric acid (90 parts), water (700 parts), isobutanol (350 parts), sodium silicate (sodium silicate No. 3) (595 parts), water (1000 Part) was added dropwise while maintaining the temperature at 0 to 10 ° C. Isoparaffin (boiling range 115 to 138 ° C.) (400 parts) was added and heated at 60 ° C. for 30 minutes. After allowing to stand and separating, the lower aqueous layer was discarded. After azeotropic dehydration, isoparaffin was added so that the non-volatile content of the solution layer was 60%, and the insoluble content was removed by filtration to add Me ₃ SiO _0.5 units and SiO ₂ units in 94% yield. An isoparaffin solution of polysiloxane II was obtained. The molar ratio of Me ₃ SiO _0.5 unit / SiO ₂ unit was 0.84.

[Synthesis Example 3]
A mixture of hexamethyldisiloxane (64 parts), water (60 parts), hydrochloric acid (40 parts), ethanol (20 parts) and isoparaffin (40 parts) was added tetraethoxysilane (208 parts) while maintaining 70 ° C. The solution was added dropwise and heated at 70 ° C. for 5 hours. The organic layer was washed with water after standing and separation. The aqueous layer was discarded and then azeotropically dehydrated. Isoparaffin was added so that the non-volatile content of the solution layer was 60%, the insoluble content was removed by filtration, and the polysiloxane III containing Me ₃ SiO _0.5 units and SiO ₂ units in 90% yield was obtained. An isoparaffin solution was obtained. The molar ratio of Me ₃ SiO _0.5 unit / SiO ₂ unit was 0.79.

[Synthesis Example 4]
To a mixture of 36% hydrochloric acid (202 parts) and water (794 parts), a mixture of sodium silicate (sodium silicate 3) (480 parts) and water (268 parts) was added dropwise while maintaining the temperature at 0 to 10 ° C. A hydrosol was formed. Subsequently, isopropanol (527 parts) was added, and then a mixture of trimethylchlorosilane (317 parts) and toluene (366 parts) was added dropwise while maintaining 15 ° C. Then, it heated at 60 degreeC for 30 minutes. After allowing to stand and separating, the lower aqueous layer was discarded. Sodium bicarbonate was added to the organic layer to neutralize excess acid. After azeotropic dehydration, toluene was added so that the nonvolatile content of the solution layer was 60%. Insoluble matter was removed by filtration to obtain a toluene solution of polysiloxane IV containing _0.5 units of Me ₃ SiO and ₂ units of SiO _{2 in} a yield of 75%. The molar ratio of Me ₃ SiO _0.5 unit / SiO ₂ unit was 0.85.

[Synthesis Example 5]
In a mixture of trimethylchlorosilane (266 parts), 36% hydrochloric acid (90 parts), water (700 parts), isobutanol (350 parts), sodium silicate (sodium silicate No. 3) (595 parts), water (1000 Part) was added dropwise while maintaining the temperature at 0 to 10 ° C. Toluene (400 parts) was added and heated at 60 ° C. for 30 minutes. After allowing to stand and separating, the lower aqueous layer was discarded. After azeotropic dehydration, toluene is added so that the non-volatile content of the solution layer is 60%, and insolubles are removed by filtration to obtain Me ₃ SiO _0.5 units and SiO ₂ units in a yield of 92%. A toluene solution of polysiloxane V was obtained. The molar ratio of Me ₃ SiO _0.5 unit / SiO ₂ unit was 0.84.

[Example 1]
Polydimethylsiloxane VI (40 parts) having a viscosity of 33,000 mPa · s when dissolved in toluene to a concentration of 30% and having a molecular chain end blocked with an OH group, Me produced in Synthesis Example 1 _From a 60% isoparaffin solution (100 parts) and isoparaffin (26.7 parts) of polysiloxane I (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.85) composed of ₃ SiO _0.5 units and SiO ₂ units To the resulting solution, 28% aqueous ammonia (0.5 parts) was added and stirred at room temperature for 6 hours. Thereafter, the mixture was heated for 4 hours while refluxing to distill off ammonia gas and water, then allowed to cool, and isoparaffin corresponding to distilled isoparaffin was added.
The above product (siloxane content 60%) (100 parts) was mixed with benzoyl peroxide 50% silicone paste (2.4 parts), isoparaffin (25 parts), methyl isobutyl ketone (25 parts), and siloxane content was mixed. About 40% silicone adhesive composition solution was prepared. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content.

[Example 2]
The composition was prepared in the same manner, using a 60% isoparaffin solution of polysiloxane I of Example 1 as a 60% isoparaffin solution of polysiloxane II. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

[Example 3]
The composition was prepared in the same manner by using a 60% isoparaffin solution of polysiloxane I of Example 1 as a 60% isoparaffin solution of polysiloxane III. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

[Comparative Example 1]
The composition was prepared in the same manner by using a 60% isoparaffin solution of polysiloxane I of Example 1 as a 60% toluene solution of polysiloxane IV. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

[Comparative Example 2]
A 60% isoparaffin solution of polysiloxane I of Example 1 was used as a 60% toluene solution of polysiloxane V, and the composition was similarly prepared. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

[Example 4]
When dissolved in toluene to a concentration of 30%, the viscosity was 27,000 mPa · s, had 0.15 mol% of methylvinylsiloxane units, and the molecular chain ends were blocked with SiMe ₂ Vi groups. 60% isoparaffin solution of polysiloxane I (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.85) composed of vinyl group-containing polydimethylsiloxane VII (40 parts), Me ₃ SiO _0.5 unit, SiO ₂ unit To a solution consisting of (100 parts) and isoparaffin (26.7 parts), 28% aqueous ammonia (0.5 parts) was added and stirred at room temperature for 6 hours. Thereafter, the mixture was heated for 4 hours while refluxing to distill off ammonia gas and water, then allowed to cool, and isoparaffin corresponding to distilled isoparaffin was added.

  To this product, a crosslinking agent of the following formula (0.25 part) and ethynylcyclohexanol (0.20 part) were added and mixed.

  To the above mixture (siloxane content 60%) (100 parts) is added heptane (50 parts), a platinum-vinyl group-containing siloxane complex silicone solution (0.5 parts) containing 0.5% by mass of platinum, and By mixing, a silicone pressure-sensitive adhesive composition solution having a siloxane content of about 40% was prepared. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and toluene residual amount. The results are shown in Table 1.

[Example 5]
The composition was prepared in the same manner as the 60% isoparaffin solution of polysiloxane I of Example 4 as a 60% isoparaffin solution of polysiloxane II. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

[Example 6]
The composition was prepared in the same manner as the 60% isoparaffin solution of polysiloxane I in Example 4 as a 60% isoparaffin solution of polysiloxane III. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

[Comparative Example 3]
The composition was prepared in the same manner using a 60% isoparaffin solution of polysiloxane I of Example 4 as a 60% toluene solution of polysiloxane IV. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

[Comparative Example 4]
The composition was prepared in the same manner using a 60% isoparaffin solution of polysiloxane I of Example 4 as a 60% toluene solution of polysiloxane V. The silicone adhesive was measured for adhesive residue, adhesive strength, holding power, and residual toluene content. The results are shown in Table 1.

Claims (3)

(A) Polydiorganosiloxane 20 to 80 parts by mass (B) R ¹ ₃ SiO _0.5 units and SiO ₂ units are contained, and the molar ratio of R ¹ ₃ SiO _0.5 units / SiO ₂ units is 0.6 to A polyorganosiloxane (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) which is 1.7 and (a) a hydrosol in the presence of an acid in a solvent containing sodium silicate and water. And (b) a method comprising a step of reacting a hydrosol with a triorganohalosilane, (b) a method comprising adding sodium silicate into a mixed system comprising a triorganohalosilane and an acid, and (c) ) Aromatic hydrocarbon solution by a method selected from a method comprising a step of reacting tetraalkoxysilane and / or its hydrolyzate with hexaorganodisiloxane in the presence of an acid. The are those prepared without the use polyorganosiloxane 80-20 parts by weight (C) an organic peroxide curing agent (A), with respect to 100 parts by weight of (B) 0.5 to 5.0 Part by mass (D) Total of at least one aliphatic organic solvent (A), (B) selected from hexane, heptane, isooctane, octane, decane, cyclohexane, methylcyclohexane, and isoparaffin (boiling range 115 to 138 ° C.) peroxide curing type silicone pressure-sensitive adhesive composition characterized and Turkey, such from 25 to 900 parts by weight per 100 parts by weight. (A ′) 20 to 80 parts by mass of a polydiorganosiloxane having two or more alkenyl groups in one molecule (B) containing R ¹ ₃ SiO _0.5 units and SiO ₂ units, and R ¹ ₃ SiO _0.5 A polyorganosiloxane having a unit / SiO ₂ unit molar ratio of 0.6 to 1.7 (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) , (a) sodium silicate and water A method comprising: forming a hydrosol in the presence of an acid in a solvent containing: and reacting the hydrosol with a triorganohalosilane; and (b) a silica in a mixed system containing the triorganohalosilane and the acid. A method comprising a step of adding sodium acid, and (c) a method comprising a step of reacting tetraalkoxysilane and / or a hydrolyzate thereof with hexaorganodisiloxane in the presence of an acid. The methods et selected, aromatic hydrocarbons polyorganosiloxane 80-20 parts by weight are those prepared without the use of hydrocarbon solvent (E) a polyorganosiloxane containing SiH group (A ') alkenyl in component The amount by which the molar ratio of the SiH group in the component (E) to the group is 0.5-20. (G) Addition reaction catalyst (A ') 5 to 2000 ppm as a metal component with respect to the total of components (B)
(D) A total of 100 of at least one aliphatic organic solvent (A ′) and (B) selected from hexane, heptane, isooctane, octane, decane, cyclohexane, methylcyclohexane, and isoparaffin (boiling range: 115 to 138 ° C.) the addition reaction silicone adhesive composition characterized and Nalco from 25 to 900 parts by mass per part by mass. A pressure-sensitive adhesive tape, sheet or label produced by applying the silicone pressure-sensitive adhesive composition according to claim 1 or 2 to a substrate.