JP2004190013A - Silicone pressure-sensitive adhesive composition and pressure-sensitive adhesive tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silicone pressure-sensitive adhesive composition which can be released cleanly without leaving the adhesive even if it is attached on a metal, a stainless steel in particular, for sticking and masking and undergoes a 300°C high temperature history and to provide a pressure-sensitive adhesive tape using it. <P>SOLUTION: This composition is a peroxide-curing silicone pressure-sensitive adhesive composition comprising (A) a polydiorganosiloxane, (B) a polyorganosiloxane which comprises an R<SP>1</SP><SB>3</SB>SiO<SB>0.5</SB>unit and a SiO<SB>2</SB>unit and whose molar ratio, R<SP>1</SP><SB>3</SB>SiO<SB>0.5</SB>unit / SiO<SB>2</SB>unit, is 0.6-1.7, (C) a hindered amine compound and (D) an organic peroxide curing agent, or an addition-reaction silicone pressure-sensitive adhesive composition comprising (A') a polydiorganosiloxane having at least two alkenyl groups in a molecule, (B) the polyorganosiloxane, (C) the hindered amine compound, (E) a polyorganosiloxane having a SiH group, (F) a controlling agent and (G) a platinum catalyst. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention particularly relates to a silicone pressure-sensitive adhesive composition and a pressure-sensitive adhesive tape, in which a pressure-sensitive adhesive is adhered to stainless steel or the like, and after aging at 280 ° C., the adhesive is not left even after the pressure-sensitive adhesive is peeled off.

  Adhesive tapes and labels that use silicone adhesives include acrylic adhesives, rubber adhesives, and urethanes because the silicone adhesive layer has excellent heat resistance, cold resistance, weather resistance, electrical insulation, and chemical resistance. A pressure-sensitive adhesive and an epoxy-based pressure-sensitive adhesive are used in a severe environment where the quality is deteriorated or deteriorated.

  For example, when a heat treatment is performed at the time of manufacturing or processing a part, it may be necessary to protect the entire surface or a part, or to perform masking or temporary fixing. As the pressure-sensitive adhesive tape used for such an application, a tape using a silicone pressure-sensitive adhesive which can be peeled off even after heating at 250 ° C. is preferable. However, in recent years, heat treatment has been performed at a higher temperature than in the past, and it has been necessary to improve the heat resistance of the silicone adhesive.

  For example, with the practical use of lead-free solder for mounting electronic components, the reflow temperature at which the electronic components are soldered to the substrate becomes higher than before, and the peak temperature may reach 280 ° C. Therefore, the adhesive must not be peeled off even at such a high temperature, and when the treatment is completed, it is necessary to be able to peel off the adhesive without moving to the adhered pair or remaining.

  Adhesive tape using a conventional silicone adhesive is applied or masked to a metal part, and if a high temperature history of 150 to 250 ° C is received, the adhesive remains on the metal part when the adhesive tape is peeled off and removed. In some cases, the pressure-sensitive adhesive layer migrated from the base material of the tape to the metal portion. This is called glue residue. This is because the silicone pressure-sensitive adhesive is oxidized and deteriorated by heating, and the cohesive force of the pressure-sensitive adhesive layer is reduced, thereby destroying the pressure-sensitive adhesive layer.

  On the other hand, by using an adhesive tape containing an antioxidant in a silicone adhesive when manufacturing semiconductor components and copper lead frame laminated components, the adhesive will not deteriorate even in a process of about 200 ° C. for several hours. Is known. (See Patent Document 1)

  Also, by adding a phenolic antioxidant to the addition reaction-curable silicone pressure-sensitive adhesive composition, it is possible to obtain a silicone pressure-sensitive adhesive that does not leave glue on metals such as copper. Provided is a silicone pressure-sensitive adhesive composition and a pressure-sensitive adhesive tape which can be stuck and masked on an adherend such as iron, and can be peeled cleanly without leaving adhesive residue even when subjected to a high temperature history of 150 to 250 ° C. I do. (See Patent Document 2)

  However, when a high-temperature history exceeding 280 ° C. is given to the silicone adhesive to which the antioxidant has been added as described above, the adhesive tape is peeled off, particularly when the metal is a metal such as copper, a copper alloy, or iron. Sometimes glue residue occurs.

  The present invention is an improvement of the above-mentioned circumstances. It is intended to adhere to or adhere to an adherend such as a metal, particularly stainless steel, and to perform a clean peel without leaving adhesive residue even when subjected to a high temperature history of 280 ° C. It is an object of the present invention to provide a silicone pressure-sensitive adhesive composition and a pressure-sensitive adhesive tape which are capable of performing pressure-sensitive adhesive bonding.

JP 2001-345415 A Japanese Patent Application No. 2001-290863 (JP-A-2003-96429)

The present inventors have conducted intensive studies to achieve the above object. As a result, by adding a hindered amine compound to the silicone pressure-sensitive adhesive composition, the pressure-sensitive adhesive was stuck to a metal, especially stainless steel, etc. After performing the heat aging, it was found that even if the pressure-sensitive adhesive was peeled off, the adhesive did not remain on the stainless steel and the effect of being able to be peeled cleanly was achieved, and the present invention was accomplished. Was.
The silicone pressure-sensitive adhesive composition used in the present invention may be any of an organic peroxide curable type, an addition reaction curable type and the like.

Accordingly, the following are used as the peroxide-curable silicone pressure-sensitive adhesive composition of the present invention.
(A) containing polydiorganosiloxane 20-80 parts by weight _^(B) R 1 _{3 SiO 0.5} units and SiO ₂ ^units, the molar ratio of _R 1 _{3 SiO 0.5} units / SiO ₂ units 0.6 1.7 to 20 parts by weight of a polyorganosiloxane (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) (C) A hindered amine compound having a structure represented by the following formula (A), (B) ) For a total of 100 parts by weight of 0.01 to 1.0 part by weight

（Ｒは炭素数１から６の１価炭化水素基。）
（Ｄ）有機過酸化物硬化剤
（Ａ）、（Ｂ）の合計１００重量部に対して ０．１〜５．０重量部
を含有する過酸化物硬化型シリコーン粘着剤組成物を提供する。また、本発明は、プラスチックフィルムの少なくとも１面に上記のシリコーン粘着剤組成物の硬化物層が積層されていることを特徴とする粘着テープを提供する。

(R is a monovalent hydrocarbon group having 1 to 6 carbon atoms.)
(D) A peroxide-curable silicone pressure-sensitive adhesive composition containing 0.1 to 5.0 parts by weight based on 100 parts by weight of the total of the organic peroxide curing agents (A) and (B). The present invention also provides a pressure-sensitive adhesive tape characterized in that a cured layer of the above-mentioned silicone pressure-sensitive adhesive composition is laminated on at least one surface of a plastic film.

The following are used as the addition reaction-curable silicone pressure-sensitive adhesive composition.
(A ') in a molecule contain a polydiorganosiloxane 20-80 parts by weight _^(B) R 1 _{3 SiO 0.5} units and SiO ₂ units having two or more alkenyl ^groups, _R 1 _{3 SiO 0.5} units / polyorganosiloxane molar ratio of SiO ₂ units is 0.6 to 1.7 ^{(R 1} is a monovalent hydrocarbon group having 1 to 10 carbon atoms.) 80-20 parts by weight (C) represented by the following formula Amine compound having a structure represented by the formula (A ') and 0.01 to 1.0 parts by weight with respect to 100 parts by weight in total.

（Ｒは上記で示したと同じ基。）
（Ｅ）ＳｉＨ基を含有するポリオルガノシロキサン （Ａ'）成分中のアルケニル基に対する（Ｅ）成分中のＳｉＨ基のモル比が０．５〜２ ０となる量
（Ｆ）制御剤 （Ａ'）、（Ｂ）の合計１００重量部に対して ０〜８．０重量部
（Ｇ）白金触媒 （Ａ'）、（Ｂ）成分の合計に対し白金分として１〜５０００ｐｐｍ
を含有する付加反応型シリコーン粘着剤組成物を提供する。また、本発明は、プラスチックフィルムの少なくとも１面に上記のシリコーン粘着剤組成物の硬化物層が積層されていることを特徴とする粘着テープを提供する。

(R is the same group as described above.)
(E) SiH group-containing polyorganosiloxane (A ') An amount such that the molar ratio of the SiH group in the component (E) to the alkenyl group in the component (A') is 0.5 to 20. 0 to 8.0 parts by weight based on 100 parts by weight of (B) and (B).
The present invention provides an addition reaction type silicone pressure-sensitive adhesive composition containing The present invention also provides a pressure-sensitive adhesive tape characterized in that a cured layer of the above-mentioned silicone pressure-sensitive adhesive composition is laminated on at least one surface of a plastic film.

  According to the present invention, there is provided a silicone pressure-sensitive adhesive composition which can be stuck and masked on an adherend such as a metal, particularly stainless steel, and which can undergo a high-temperature history of 280 ° C., does not cause adhesive residue, and can be peeled cleanly. An adhesive tape can be obtained.

The following are used as the peroxide-curable silicone pressure-sensitive adhesive composition of the present invention.
(A) containing polydiorganosiloxane 20-80 parts by weight _^(B) R 1 _{3 SiO 0.5} units and SiO ₂ ^units, the molar ratio of _R 1 _{3 SiO 0.5} units / SiO ₂ units 0.6 1.7 to 20 parts by weight of a polyorganosiloxane (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) (C) A hindered amine compound having a structure represented by the following formula (A), (B) ) For a total of 100 parts by weight of 0.01 to 1.0 part by weight

（Ｒは炭素数１から６の１価炭化水素基。）
（Ｄ）有機過酸化物硬化剤
（Ａ）、（Ｂ）の合計１００重量部に対して ０．１〜５．０重量部
を含有する過酸化物硬化型シリコーン粘着剤組成物を提供する。また、本発明は、プラスチックフィルムの少なくとも１面に上記のシリコーン粘着剤組成物の硬化物層が積層されていることを特徴とする粘着テープを提供する。

(R is a monovalent hydrocarbon group having 1 to 6 carbon atoms.)
(D) A peroxide-curable silicone pressure-sensitive adhesive composition containing 0.1 to 5.0 parts by weight based on 100 parts by weight of the total of the organic peroxide curing agents (A) and (B). The present invention also provides a pressure-sensitive adhesive tape characterized in that a cured layer of the above-mentioned silicone pressure-sensitive adhesive composition is laminated on at least one surface of a plastic film.

  In this case, these silicone pressure-sensitive adhesive compositions and pressure-sensitive adhesive tapes are effectively used for masking tapes of metals, particularly stainless steel.

More specifically, the component (A) is a polydiorganosiloxane, and is preferably represented by the following formula.
^{_{R 2 3 SiO- (R 2 2}} SiO) p -SiR 2 3
^{_{R 2 2 (HO) SiO- (}} R 2 2 SiO) p -SiR 2 2 (OH)
In the formula, R ² is the same or different hydrocarbon group having 1 to 10 carbon atoms. In order to improve heat resistance, 0 to 35 mol%, particularly 2 to 20 mol%, of all organic groups bonded to a silicon atom. % Are selected to be phenyl groups. Further, it is preferred that 1 to 35 mol%, particularly 2 to 20 mol%, of all siloxane units are diphenylsiloxane units. p is a number that makes the viscosity at 25 ° C. of the polydiorganosiloxane 500 mPa · s or more.

Here, R ² is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms. Examples thereof include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a cycloalkyl group such as a cyclohexyl group, and phenyl. And an aryl group such as a tolyl group, particularly preferably a methyl group or a phenyl group.

  The properties of the polydiorganosiloxane may be oily or raw rubbery. The viscosity of the component (A) is at least 500 mPa · s at 25 ° C. if it is oily. In particular, it is preferably 10,000 mPa · s or more. When the viscosity is 500 mPa · s or less, the curability is lowered and the cohesive force (retention force) is lowered, which is not suitable. In the case of a raw rubber-like material, the viscosity when dissolved in toluene so as to have a concentration of 30% is preferably 100,000 mPa · s or less. When the viscosity exceeds 100,000 mPa · s, the composition becomes too high in viscosity, and it becomes difficult to stir during production. Further, two or more types of the component (A) may be used in combination.

(B) component contains and SiO ₂ units ^R ₁ 3 _{SiO 0.5} units (monovalent hydrocarbon group. ^{R 1} s 1 to 10 carbon ^atoms), _R 1 _{3 SiO 0.5} units / SiO ₂ units Is a polyorganosiloxane having a molar ratio of 0.6 to 1.7. In R ¹ ₃ molar ratio of SiO _0.5 units / SiO ₂ units is less than 0.6 may adhesive strength or tackiness is lowered, it is possible to decrease the adhesive strength and holding power exceeds 1.7. R ¹ includes 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. A methyl group is preferred.

The component (B) may contain an OH group, and the OH group content is preferably 4.0% by weight or less. Those having more than 4.0% by weight of OH groups are not preferred because the curability of the pressure-sensitive adhesive decreases. 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 component (B) may be used in combination of two or more.

The components (A) and (B) may be used as a simple mixture, or when the component (A) contains the following formula,
_{^{R 2 2 (HO) SiO- (}} R 2 2 SiO) p -SiR 2 2 (OH)
(P is the same as described above.)

The components (A) and (B) may be used as a condensation reaction product. In order to carry out the condensation reaction, a mixture of the components (A) and (B) dissolved in a solvent such as toluene may be reacted at room temperature to reflux using an alkaline catalyst.

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

The component (C) is a hindered amine compound. In particular, those having the following structure in the molecule are preferable.

ここで、Ｒは炭素数１から６の１価炭化水素基であり、例示すると、メチル基、エチル基、プロピル基、ブチル基などのアルキル基、シクロヘキシル基などのシクロアルキル基、フェニル基などのアリール基などであり、特にメチル基が好ましい。

Here, R is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and examples thereof include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a cycloalkyl group such as a cyclohexyl group, and a phenyl group. It is an aryl group etc., and a methyl group is particularly preferable.

In particular,

  Component (C) may be added in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the total of components (A) and (B). Particularly, 0.05 to 0.5 part by weight is preferable. If the amount is less than 0.01 part by weight, there is no effect of improving heat resistance, and if it exceeds 1 part by weight, the holding power may be reduced. Two or more components (C) may be used in combination.

  The component (D) is an organic peroxide curing agent, specifically, dibenzoyl peroxide, 4,4′-dimethyldibenzoyl peroxide, 3,3′-dimethyldibenzoyl peroxide, 2,2′-dimethyl. Examples thereof include dibenzoyl peroxide, 2,2 ′, 4,4′-tetrachlorodibenzoyl peroxide and cumyl peroxide.

  Component (D) may be added in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the total of components (A) and (B). Particularly preferred is 1 to 4 parts by weight. If the amount is less than 0.1 part by weight, the curability and the holding power may decrease. If the amount exceeds 5 parts by weight, the pressure-sensitive adhesive layer may be colored or the holding power may be reduced. The form of the component (D) is not particularly limited. The component (D) alone, the component (D) diluted in an organic solvent, water-dispersed product, silicone oil-dispersed product in paste form, and the like can be mentioned. As the component (D), two or more types may be used in combination.

The following are used as the addition reaction-curable silicone pressure-sensitive adhesive composition.
(A ') in a molecule contain a polydiorganosiloxane 20-80 parts by weight _^(B) R 1 _{3 SiO 0.5} units and SiO ₂ units having two or more alkenyl ^groups, _R 1 _{3 SiO 0.5} units / polyorganosiloxane molar ratio of SiO ₂ units is 0.6 to 1.7 ^{(R 1} is a monovalent hydrocarbon group having 1 to 10 carbon atoms.) 80-20 parts by weight (C) represented by the following formula Amine compound having a structure represented by the formula (A ') and 0.01 to 1.0 parts by weight with respect to 100 parts by weight in total.

（Ｒは上記で示したと同じ基。）
（Ｅ）ＳｉＨ基を含有するポリオルガノシロキサン （Ａ'）成分中のアルケニル基に対する（Ｅ）成分中のＳｉＨ基のモル比が０．５〜２ ０となる量
（Ｆ）制御剤 （Ａ'）、（Ｂ）の合計１００重量部に対して ０〜８．０重量部
（Ｇ）白金触媒 （Ａ'）、（Ｂ）成分の合計に対し白金分として１〜５０００ｐｐｍ
を含有する付加反応型シリコーン粘着剤組成物を提供する。また、本発明は、プラスチックフィルムの少なくとも１面に上記のシリコーン粘着剤組成物の硬化物層が積層されていることを特徴とする粘着テープを提供する。

(R is the same group as described above.)
(E) SiH group-containing polyorganosiloxane (A ') An amount such that the molar ratio of the SiH group in the component (E) to the alkenyl group in the component (A') is 0.5 to 20. 0 to 8.0 parts by weight based on 100 parts by weight of (B) and (B).
The present invention provides an addition reaction type silicone pressure-sensitive adhesive composition containing The present invention also provides a pressure-sensitive adhesive tape characterized in that a cured layer of the above-mentioned silicone pressure-sensitive adhesive composition is laminated on at least one surface of a plastic film.

  In this case, these silicone pressure-sensitive adhesive compositions and pressure-sensitive adhesive tapes are effectively used for masking tapes of metals, particularly stainless steel.

More specifically, the component (A ') is an alkenyl group-containing polydiorganosiloxane, and is preferably represented by the following formula.
_{^{R 4 (3-a) X}} a SiO- (R 4 XSiO) m - (R 4 2 SiO) n -SiR 4 (3-a) X a
_{^{R 4 2 (HO) SiO- (}} R 4 XSiO) m + 2 - (R 4 2 SiO) n -SiR 4 2 (OH)
(Wherein, R ⁴ is a monovalent hydrocarbon group having no aliphatic unsaturated bond, X is an alkenyl group-containing organic group, a is an integer of 0 to 3, preferably 1, m is 0 or more, n Is a number of 100 or more, and a and m do not simultaneously become 0. Further, m + n is a number that makes the viscosity at 25 ° C. of the polydiorganosiloxane 500 mPa · s or more.)

Here, as R ⁴ , those having 1 to 10 carbon atoms are preferable, and examples thereof include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a cycloalkyl group such as a cyclohexyl group, a phenyl group, and a tolyl group. And particularly preferred are a methyl group and a phenyl group.

  As the alkenyl group-containing organic group for X, those having 2 to 10 carbon atoms are preferable, and a vinyl group, allyl group, hexenyl group, octenyl group, acryloylpropyl group, acryloylmethyl group, methacryloylpropyl group, cyclohexenylethyl group, vinyl An oxypropyl group and the like, and particularly, a vinyl group is industrially preferable.

The properties of the polydiorganosiloxane may be oily or raw rubbery.
The viscosity of the component (A ′) at 25 ° C. is 1000 mPa · s or more if it is oily. In particular, it is preferably 10,000 mPa · s or more. When the viscosity is 1000 mPa · s or less, the curability is lowered and the cohesive force (retention force) is lowered, which is not suitable. In the case of a raw rubber-like material, the viscosity when dissolved in toluene so as to have a concentration of 30% is preferably 100,000 mPa · s or less. When the viscosity exceeds 100,000 mPa · s, the composition becomes too high in viscosity, and it becomes difficult to stir during production. Further, two or more components (A ') may be used in combination.

Component (B) ^R ₁ 3 _{SiO 0.5} units ^{(R 3} is defined above) contain and SiO ₂ ^units, the molar ratio of _R 1 _{3 SiO 0.5} units / SiO ₂ units 0.6 to 1.7 Is a polyorganosiloxane. In R ¹ ₃ molar ratio of SiO _0.5 units / SiO ₂ units is less than 0.6 may adhesive strength or tackiness is lowered, it is possible to decrease the adhesive strength and holding power exceeds 1.7. It may contain an OH group, and the OH group content is preferably 4.0% by weight or less. Those having more than 4.0% by weight of OH groups are not preferred because the curability of the pressure-sensitive adhesive decreases.

As the component (B), two or more kinds may be used in combination. 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 component (A ′) and the component (B) may be used as a simple mixture, or when the component (A ′) contains the following formula,
^{_{R 4 2 (HO) SiO- (}} R 4 XSiO) m + 2 - (R 4 2 SiO) n -SiR 4 2 (OH)
(M and n represent the same numbers as above. R ⁴ is the same group as above.)
The component (A ′) and the component (B) may be used as a condensation reaction product. In order to carry out the condensation reaction, a mixture of the components (A ') and (B) dissolved in a solvent such as toluene may be reacted at room temperature to reflux using an alkaline catalyst.

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

  The component (C) is a hindered amine compound and is the same as described above.

  The component (E) is a crosslinking agent, which is an organohydropolysiloxane having at least two, preferably at least three, hydrogen atoms bonded to silicon atoms in one molecule, and may be a linear, branched or cyclic one. it can.

  Examples of the component (E) include the following, but are not limited thereto.

（Ｒ¹は前記の炭化水素であり、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 ¹ is the above-mentioned hydrocarbon, b is 0 or 1, x and y are integers of 0 or more. When b is 0, x is 2 or more, and the viscosity of this organohydropolysiloxane at 25 ° C. S is an integer of 2 or more, t is an integer of 0 or more, and s + t ≧ 3, preferably 8 ≧ s + t ≧ 3.)

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

  The amount of the component (E) is such that the molar ratio of the SiH group in the component (E) to the alkenyl group in the component (A ′) is in the range of 0.5 to 20, especially 0.8 to 15. Is preferred. If it is less than 0.5, the crosslink density becomes low, and the holding power may decrease accordingly. If it exceeds 20, the crosslink density becomes high and sufficient adhesive strength and tack may not be obtained. On the other hand, if it exceeds 20, the usable time of the processing solution may be shortened.

  The component (F) is a control agent, which is added in order to prevent the treatment liquid from thickening or gelling before heat curing when preparing or applying the silicone pressure-sensitive adhesive composition to a 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, -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.

  Component (F) may be added in an amount of 0 to 8.0 parts by weight, especially 0.05 to 2.0 parts by weight, based on 100 parts by weight of the total of components (A ') and (B). Is preferred. If the amount exceeds 8.0 parts by weight, the curability may decrease.

  The component (G) is a platinum-based catalyst, chloroplatinic acid, an alcohol solution of chloroplatinic acid, a reactant of chloroplatinic acid and an alcohol, a reactant of chloroplatinic acid and an olefin compound, and containing chloroplatinic acid and a vinyl group. A reaction product with siloxane is exemplified.

  The added amount is preferably 1 to 5,000 ppm, particularly preferably 5 to 2,000 ppm, as a platinum content, based on the total of the components (A ′) and (B). If it is less than 1 ppm, the curability will be reduced, the crosslinking density will be reduced, and the holding power may be reduced. If it exceeds 5,000 ppm, the usable time of the treatment bath may be shortened.

A phenolic antioxidant as the component (H) may be added to the above addition reaction-curable silicone pressure-sensitive adhesive for the purpose of further improving heat resistance.
As the component (H), those having the following structure in the molecule are particularly preferable.

Specific examples include the following.

（mは０以上、ｎは１以上の整数）

(M is an integer of 0 or more, n is an integer of 1 or more)

  Component (H) is added in an amount of 0.1 to 10 parts by weight with respect to 100 parts by weight of the total of components (A) and (B). Is not sufficiently exhibited, and if the amount is more than 10 parts by weight, the holding power may be reduced.

  In the silicone pressure-sensitive adhesive composition of the present invention, optional components other than the above components can be added. For example, non-reactive polyorganosiloxanes such as polydimethylsiloxane and polydimethyldiphenylsiloxane, and phenol-based, quinone-based, amine-based, phosphorus-based, phosphite-based, sulfur-based, thioether-based antioxidants, and triazoles -Based, benzophenone-based light stabilizers, phosphate ester-based, halogen-based, phosphorus-based, antimony-based flame retardants, cationic activators, anionic activators, non-ionic activators, etc. As a solvent for decreasing the viscosity at the time, toluene, aromatic solvents such as xylene, hexane, octane, aliphatic solvents such as isoparaffin, methyl ethyl ketone, ketone solvents such as methyl isobutyl ketone, ethyl acetate, isobutyl acetate and the like Ester solvent, diisopropyl ether, 1,4-dioxide Ether solvents such as Sun, or a mixed solvent, a dye, a pigment is 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, plastic film such as polyvinyl chloride, aluminum foil, metal foil such as copper foil, Japanese paper, synthetic paper, Examples include paper such as polyethylene laminated paper, cloth, glass fiber, and a composite base material obtained by laminating a plurality of these materials.

  In order to improve the adhesion between these base materials and the adhesive layer, those subjected to a primer treatment, a corona treatment, an etching treatment, or a plasma treatment may be used.

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

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

  The adhesive tape may be manufactured by directly applying to the base material as described above, or may be applied to a release film or release paper that has been subjected to release coating, cured, and then bonded to the above base material. The adhesive tape may be manufactured by a transfer method.

  The adherend that can be masked with the pressure-sensitive adhesive tape produced using the silicone pressure-sensitive adhesive composition of the present invention is not particularly limited, but the following can be exemplified. Metals such as stainless steel, copper, iron, etc., metals whose surfaces have been plated or rust-proof, glass, ceramics, ceramics, resins such as polytetrafluoroethylene, polyimide, epoxy resin, novolak resin, and more. Are combined and configured.

  Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. The parts in the examples are parts by weight, and the characteristic values are measured by the following test methods. Me represents a methyl group, Ph represents a phenyl group, Bu represents a butyl group, and Vi represents a vinyl group.

The adhesive residue silicone pressure-sensitive adhesive composition solution is 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 becomes 40 μm, and then heated at 130 ° C. for 1 minute. After curing, an adhesive tape was prepared. This adhesive tape was stuck on a metal plate (polished stainless steel plate), pressed by reciprocating a roller covered with a rubber layer having a weight of 2 kg, and left in a dryer at 280 ° C. After a predetermined time, the metal plate was taken out, cooled to room temperature, and then the adhesive tape was peeled off, and it was observed whether or not the adhesive layer was cohesively broken and the adhesive remained on the surface of the metal plate. The sample that can be peeled without adhesive residue was rated as ○, the one with partial adhesive residue was rated as Δ, and the one with almost the entire surface adhesive residue was rated as x.

Adhesive force An adhesive tape was prepared in the same manner as in the evaluation of adhesive residue, the adhesive tape was attached to a stainless steel plate, and pressure-bonded by reciprocating a roller covered with a 2 kg rubber layer once. After allowing the tape to stand at room temperature for about 20 hours, the force (N / 25 mm) required to peel the tape from the stainless steel plate at a speed of 300 mm / min at an angle of 180 ° was measured using a tensile tester.

A pressure-sensitive adhesive tape was prepared in the same manner as in the evaluation of holding power and adhesive residue. This adhesive tape is stuck to the lower end of the stainless steel plate so that the adhesive area becomes 25 × 25 mm, a load of 1 kg is applied to the lower end of the adhesive tape, and the displacement distance after standing vertically at 250 ° C. for 1 hour is measured. Readings were taken with a microscope.

[Example 1]
Viscosity when dissolved in toluene to a concentration of 30% is 42,000 mPa · s, which has 6 mol% of diphenylsiloxane units, and has a phenyl group-containing polyoxygen group whose molecular chain terminals are blocked with OH groups. Dimethylsiloxane (45 parts),
60% toluene solution (92 parts) of a polysiloxane composed of _0.5 units of Me ₃ SiO and ₂ units of SiO ₂ ( _0.5 units of Me ₃ SiO / 0.82 units of SiO ₂ ), and a solution composed of toluene (30 parts) Was heated at reflux for 4 hours. After allowing to cool, a hindered amine compound I of the following formula (Adeka Stab LA57, manufactured by Asahi Denka Co., Ltd.) (0.2 part) was added and mixed.

  The above mixture (siloxane content 60%) (100 parts) was mixed with 50% benzoyl peroxide silicone paste (2.4 parts) and toluene (50 parts), and a silicone pressure-sensitive adhesive composition containing about 40% siloxane content. A solution was prepared. The adhesive adhesive property, adhesive strength and holding power of this silicone adhesive were measured. Table 1 shows the results.

Example 2
A silicone pressure-sensitive adhesive composition solution was prepared by adding a hindered amine compound II (Adeka Stab LA52, manufactured by Asahi Denka Co., Ltd.) (0.2 part) in place of the hindered amine compound I in Example 1.

このシリコーン粘着剤の糊残り性、粘着力、保持力を測定した。結果を表１に示す。

The adhesive adhesive property, adhesive strength and holding power of this silicone adhesive were measured. Table 1 shows the results.

Example 3
In Example 1, instead of phenyl group-containing dimethylpolysiloxane, the viscosity when dissolved with toluene to a concentration of 30% was 67,000 mPa · s, and the molecular chain ends were blocked with OH groups. A silicone pressure-sensitive adhesive composition solution using dimethylsiloxane (45 parts) was prepared.
The adhesive adhesive property, adhesive strength and holding power of this silicone adhesive were measured. Table 1 shows the results.

Comparative Example 1
In Example 1, a silicone pressure-sensitive adhesive composition solution to which hindered amine compound I was not added was prepared.
The adhesive adhesive property, adhesive strength and holding power of this silicone adhesive were measured. Table 1 shows the results.

Comparative Example 2
A silicone pressure-sensitive adhesive composition solution was prepared in which, in place of the hindered amine compound I in Example 1, a phenolic antioxidant III (IRGANOX 1330, manufactured by Ciba Specialty Chemicals) of the following formula (0.5 parts) was added. did. The adhesive adhesive property, adhesive strength and holding power of this silicone adhesive were measured. Table 1 shows the results.

Example 4
It has a viscosity of 27,000 mPa · s when dissolved in toluene to a concentration of 30%, has 0.15 mol% of methylvinylsiloxane units and 10 mol% of diphenylsiloxane units, and has a molecular chain terminal of SiMe _2. A vinyl group- and phenyl group-containing polydimethylsiloxane blocked with a Vi group (45 parts),
60% toluene solution (92 parts) of a polysiloxane composed of _0.5 units of Me ₃ SiO and ₂ units of SiO ₂ ( _0.5 unit of Me ₃ SiO / 0.82 units of SiO ₂ ), and a solution composed of toluene (30 parts) Was added with a hindered amine compound I (0.2 part), a crosslinking agent of the following formula (0.16 part), and ethynylcyclohexanol (0.1 part).
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  Toluene (50 parts) and platinum catalyst CAT-PL-50T (Shin-Etsu Chemical Co., Ltd.) (0.5 parts) were added to the above mixture (siloxane content 60%) (100 parts), and the mixture was further mixed. A 40% silicone pressure-sensitive adhesive composition solution was prepared. The adhesive adhesive property, adhesive strength and holding power of this silicone adhesive were measured. Table 1 shows the results.

Comparative Example 3
A silicone pressure-sensitive adhesive composition solution was prepared in which the phenolic antioxidant III (0.5 part) was added in place of the hindered amine compound I in Example 4. The adhesive adhesive property, adhesive strength and holding power of this silicone adhesive were measured. Table 1 shows the results.

Example 5
It has a viscosity of 27,000 mPa · s when dissolved in toluene to a concentration of 30%, has 0.15 mol% of methylvinylsiloxane units and 10 mol% of diphenylsiloxane units, and has a molecular chain terminal. Is a vinyl group- and phenyl group-containing polydimethylsiloxane (45 parts) capped with a SiMe ₂ Vi group,
A 60% toluene solution (92 parts) of a polysiloxane composed of _0.5 units of Me ₃ SiO and ₂ units of SiO ₂ ( _0.5 units of Me ₃ SiO / 0.80 units of SiO ₂ = 0.80), and toluene (30 parts) To the solution are added hindered amine compound I (0.2 part), phenolic antioxidant III (0.5 part), a crosslinking agent of the following formula (0.16 part) and ethynylcyclohexanol (0.1 part). Mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  Toluene (50 parts) and platinum catalyst CAT-PL-50T (manufactured by Shin-Etsu Chemical Co., Ltd.) (0.5 parts) were added to the above mixture (siloxane content 60%) (100 parts), and further mixed. About 40% of a silicone adhesive composition solution was prepared. Table 1 shows the results of measuring the adhesive residue, adhesive strength, and holding power of this silicone adhesive.

Claims (6)

(A) containing polydiorganosiloxane 20-80 parts by weight _^(B) R 1 _{3 SiO 0.5} units and SiO ₂ ^units, the molar ratio of _R 1 _{3 SiO 0.5} units / SiO ₂ units 0.6 1.7 polyorganosiloxane (R ¹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms) 80 to 20 parts by weight (C) Hindered amine compound having a structure represented by the following formula (A), (B) ) For a total of 100 parts by weight of 0.01 to 1.0 part by weight

(R is a monovalent hydrocarbon group having 1 to 6 carbon atoms.)
(D) Organic peroxide curing agent A peroxide-curable silicone pressure-sensitive adhesive composition containing 0.1 to 5.0 parts by weight based on 100 parts by weight of the total of (A) and (B). The peroxide-curable silicone pressure-sensitive adhesive composition according to claim 1, wherein the polydiorganosiloxane contains 1 to 35 mol% of diphenylsiloxy units. (A ') in a molecule contain a polydiorganosiloxane 20-80 parts by weight _^(B) R 1 _{3 SiO 0.5} units and SiO ₂ units having two or more alkenyl ^groups, _R 1 _{3 SiO 0.5} units / polyorganosiloxane molar ratio of SiO ₂ units is 0.6 to 1.7 ^{(R 1} is a monovalent hydrocarbon group having 1 to 10 carbon atoms.) 80-20 parts by weight (C) represented by the following formula Amine compound having a structure represented by the formula (A ') and 0.01 to 1.0 parts by weight with respect to 100 parts by weight in total.

(R is a monovalent hydrocarbon group having 1 to 6 carbon atoms.)
(E) SiH group-containing polyorganosiloxane (A ') An amount such that the molar ratio of the SiH group in the component (E) to the alkenyl group in the component (A') is 0.5 to 20. ), 0 to 8.0 parts by weight with respect to 100 parts by weight of the total of (B) (G) Platinum catalyst 1 to 5000 ppm as platinum content with respect to the total of the components (A ') and (B)
An addition reaction type silicone pressure-sensitive adhesive composition comprising: The addition-reaction-type silicone pressure-sensitive adhesive composition according to claim 3, wherein the polydiorganosiloxane contains 1 to 35 mol% of diphenylsiloxy units. 4. The silicone pressure-sensitive adhesive according to claim 3, wherein the phenolic antioxidant is contained as component (H) in an amount of 0.1 to 10 parts by weight based on a total of 100 parts by weight of (A) and (B). Composition. A pressure-sensitive adhesive tape, wherein a cured product layer of the silicone pressure-sensitive adhesive composition according to claim 1 or 3 is laminated on at least one surface of a plastic film.