KR20060105626A - Sheet for thermocompression bonding - Google Patents

Abstract

The present invention is to provide a thermocompression sheet excellent in peeling durability even when used for thermocompression bonding of an anisotropic conductive adhesive containing a radical polymerization curable resin.

(a) organopolysiloxanes containing alkenyl groups,

(b) thermally conductive fillers,

(c) organohydrogenpolysiloxane containing Si—H groups,

(d) platinum group metal catalysts, and

(e) antioxidants

And a sheet for thermocompression bonding having a layer containing the cured product of the composition containing, and

(A) organopolysiloxane,

(B) thermally conductive fillers, and

(C) curing agent

It is formed in the base material layer containing the hardened | cured material of the composition containing and one side or both sides of this layer,

(Iii) an alkenyl group-containing organopolysiloxane,

(Ii) Si-H group-containing organohydrogenpolysiloxanes,

(Iii) a platinum group metal catalyst, and

(Iii) antioxidants

It has a mold release layer containing the hardened | cured material of the composition containing these.

Thermocompression Sheet, Organopolysiloxane, Organohydrogenpolysiloxane, Platinum Group Metal Catalyst

Description

Thermocompression Sheet {Sheet for Thermocompression Bonding}

[Patent Document 1] Japanese Patent No. 3041213

[Patent Document 2] Japanese Unexamined Patent Publication No. 2001-18330

[Patent Document 3] Japanese Patent Application Laid-Open No. 7-214728

[Patent Document 4] Japanese Patent Application Laid-Open No. 7-11010

[Patent Document 5] Japanese Patent Application Laid-Open No. 2004-273669

The present invention is a material obtained by uniformly dispersing conductive particles in an anisotropic conductive adhesive (i.e., an adhesive having high insulating properties) using an electrode connected to a flat display panel or the like and an electrode connected to a flat display panel or the like in the production of a laminate or a flexible printed circuit board. The present invention relates to a sheet for thermocompression bonding, which is used for electrical and mechanical connection through electrical connection between electrodes of an electronic component, insulation between adjacent electrodes, and fixing purposes).

In recent years, as a display of a personal computer, a video camera, a digital camera, a navigation system, a portable TV, a thin TV, a mobile phone, and the like, flat display panels such as liquid crystal panels and plasma display panels are increasing. The electrode connected to this flat display panel and the lead electrode of the flexible printed circuit board on which the drive LSI is mounted are thermally crimped through an anisotropic conductive adhesive, and electrically and mechanically connected.

In this case, a sheet for thermocompression bonding is used for the purpose of sandwiching between the pressing tool and the flexible printed circuit board, transferring heat from the pressing tool to the anisotropic conductive adhesive, and applying uniform pressure. This thermocompression bonding sheet requires peelability to an anisotropic conductive adhesive so that it can be used repeatedly. Therefore, in some cases, a fluororesin film such as polytetrafluoroethylene (PTFE) is used, but in order to apply the pressure more uniformly, it is common to use a silicone rubber sheet having low elasticity and flexibility and good thermal conductivity. It is.

However, compared with the fluororesin film, the silicone rubber sheet tends to cause the components contained in the anisotropic conductive adhesive to migrate into the sheet and deteriorate. As a result, peeling with the anisotropic conductive adhesive became more and more difficult while repeating the thermocompression bonding by pressurization, peeling became difficult while finally bonding, and it broke, and there existed a problem in durability as a sheet for thermocompression bonding.

With respect to such a problem, a method of preparing a silicone rubber sheet and a fluororesin film (1), and using these two sheets in a superimposed manner, (2) a method of laminating and compounding (patent documents 1 to 3) and the like It is proposed.

By the way, since the method of (1) requires two types of sheets, there exists a problem that manufacturing cost (raw material cost and the cost of the manufacturing apparatus which supplies two types of sheets) becomes remarkably expensive. Moreover, in the method of (2), since the sheet | seat obtained is what silicone rubber adhere | attached with the heat resistant resin film, there exists a problem that flexibility is lower than rubber | gum single body. Therefore, when using the method of (2), it is hard to apply uniform pressure at the time of pressurization, and it is necessary to enlarge a pressing force. However, there existed a problem that the strength of a to-be-adhered body had a limit and it could not receive a pressure more than a certain level, and that a heat resistant resin film was expensive and manufacturing cost became high. Moreover, although the sheet for thermocompression bonding containing the silicone rubber which mix | blended carbon black and cerium oxide was proposed (patent document 4), durability was not fully satisfied.

Accordingly, as an improvement of these points, a thermocompression-bonding sheet in which a thin release layer having a composition different from that of the sheet is laminated on the surface in contact with the anisotropic conductive adhesive on the silicone rubber sheet and improving the peelability with the adhesive is proposed. (Patent Document 5). By the way, in this sheet, when it applies to the anisotropic conductive adhesive containing resin of the kind hardened | cured by radical polymerization (henceforth "radical polymerization hardening type resin"), the component of the said adhesive will transfer to the said release layer, and The release durability of was not obtained.

Therefore, an object of the present invention is to provide a thermocompression bonding sheet having excellent peeling durability even when used for thermocompression bonding of an anisotropic conductive adhesive containing a radical polymerization curable resin.

The present invention firstly,

(a) organopolysiloxane having two or more alkenyl groups bonded to a silicon atom: 100 parts by mass,

(b) thermally conductive filler: 20 to 2,000 parts by mass,

(c) organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms: per hydrogen of alkenyl groups bonded to the silicon atoms in the component (a), the hydrogen atoms bonded to the silicon atoms in the component (c) from 0.3 to 50 Molar volume,

(d) platinum group metal catalysts: an effective amount, and

(e) Antioxidant: 0.001-30 mass parts

It provides a sheet for thermocompression bonding (hereinafter referred to as "sheet for thermocompression bonding") having a layer containing a cured product of a composition containing a.

In addition, the present invention, second,

(A) organopolysiloxane: 100 parts by mass,

(B) thermally conductive filler: 20 to 2,000 parts by mass, and

(C) curing agent: effective amount

It is formed in the base material layer containing the hardened | cured material of the composition containing this, and one side or both sides of this layer,

(Iii) organopolysiloxane having two or more alkenyl groups bonded to a silicon atom: 100 parts by mass,

(Ii) organohydrogenpolysiloxanes having two or more hydrogen atoms bonded to silicon atoms: 0.3 to 50 hydrogen atoms bonded to the silicon atoms in the component (ii) per one mole of alkenyl group bonded to the silicon atom in the component (iii) Molar volume,

(Iii) a platinum group metal catalyst: an effective amount, and

(Iii) Antioxidant: 0.001-30 mass parts

It provides the sheet for thermocompression bonding which has a mold release layer containing the hardened | cured material of the composition containing (henceforth "sheet for thermocompression bonding").

Best Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Hereinafter, the thermocompression seat of this invention is demonstrated in detail.

<Sheet A for Thermal Compression>

The thermocompression bonding sheet A of the present invention is a thermocompression bonding sheet having a layer containing a cured product of the composition containing the following components (a) to (e). The detail of each component is as follows.

About composition

(A) organopolysiloxanes having two or more alkenyl groups bonded to silicon atoms

The organopolysiloxane which has the alkenyl group of (a) component has two or more, preferably three or more alkenyl groups in 1 molecule.

The organopolysiloxane having an alkenyl group of component (a) is, for example, an average composition formula:

R ¹ _a SiO _{(4-a) / 2} (1)

(Wherein a is a number from 1.95 to 2.05 and R ¹ is independently an unsubstituted or substituted monovalent hydrocarbon group.)

Is displayed. The average degree of polymerization of the organopolysiloxane of the component (a) is usually 200 to 100,000, preferably 1,000 to 50,000, and more preferably 3,000 to 20,000. If the average degree of polymerization is less than 200, the strength of the cured product may be lowered and the cured product may be weakened. If the average degree of polymerization is more than 100,000, the moldability of the composition may deteriorate, and a sheet of desired precision may not be obtained. In addition, 0.001 to 5 mol%, preferably 0.001 to 1 mol% of R ¹ is an alkenyl group.

Among the monovalent hydrocarbon groups represented by R ¹ in the above average composition formula (1), examples of groups other than alkenyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl Alkyl groups such as groups, pentyl groups, neopentyl groups, hexyl groups, heptyl groups, octyl groups, nonyl groups, decyl groups and dodecyl groups; Cycloalkyl groups such as cyclopentyl group, cyclohexyl group and cycloheptyl group; Aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group and biphenylyl group; Aralkyl groups such as benzyl, phenylethyl, phenylpropyl and methylbenzyl; And some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms such as fluorine, chlorine and bromine, cyano groups, for example, chloromethyl group, 2-bromoethyl group, 3-chloro Propyl group, 3,3,3-trifluoropropyl group, chlorophenyl group, fluorophenyl group, cyanoethyl group, 3,3,4,4,5,5,6,6,6-nonnafluorohexyl group The carbon atom number is 1-12, especially 1-10, Especially 1-6 are mentioned. Among these, an unsubstituted or substituted alkyl group having 1 to 3 carbon atoms such as methyl group, ethyl group, propyl group, chloromethyl group, 2-bromoethyl group, 3,3,3-trifluoropropyl group, etc .; And phenyl groups are preferred. In R <^1> , especially, it is preferable that a methyl group is 50 mol% or more, especially 80 mol% or more.

Among the monovalent hydrocarbon groups represented by R ¹ , as the alkenyl group, the number of carbon atoms such as vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group, hexenyl group, cyclohexenyl group is usually 2 to 3, for example. The thing of about 8 is mentioned, Among these, lower alkenyl groups, such as a vinyl group and an allyl group, are preferable, and a vinyl group is especially preferable.

In addition, the organopolysiloxane of the component (a) is usually sealed at the molecular chain terminal with a triorganosilyl group or a hydroxyl group. Examples of the triorganosilyl group include trimethylsilyl group, dimethylvinylsilyl group, trivinylsilyl group and the like.

In addition, (a) component may be used individually by 1 type or in combination of 2 or more types.

(B) thermally conductive fillers

The thermally conductive filler of (b) component is added in order to make the thermal conductivity of the sheet | seat for thermocompression bonding favorable. Specific examples thereof include metal oxides such as alumina, silica, and zinc oxide; Metal nitrides such as aluminum nitride, boron nitride, and silicon nitride; Metal carbides such as silicon carbide; Metal powders such as aluminum powder and silver powder; Diamond powder; Carbon black, such as carbon graphite, acetylene black, and furnace black, etc. are mentioned.

These thermally conductive fillers, except for carbon black, have an average particle diameter of 0.1 to 100 µm, preferably 0.3 to 50 µm, and more preferably 0.5 to 30 µm. In addition, the average particle diameter when the thermally conductive filler is carbon black is preferably 10 m 2 / g or more, more preferably 30 m 2 / g or more, and still more preferably 50 m 2 / g or more, with a BET specific surface area.

The compounding quantity of (b) component needs to be 20-2,000 mass parts with respect to 100 mass parts of said (a) component in the composition obtained, Preferably it is 30-1,500 mass parts, More preferably, it is 50-1,000 mass parts. . When the compounding amount is less than 20 parts by mass, the sheet for thermocompression bonding is not to have a desired thermal conductivity, and heat applied to the anisotropic conductive adhesive is insufficient, and when the amount exceeds 2,000 parts by mass, the sheet is weak. Hardness becomes too high, and uniform crimping becomes difficult.

In addition, (b) component may be used individually by 1 type or in combination of 2 or more types.

(C) organohydrogenpolysiloxanes having two or more hydrogen atoms bonded to silicon atoms

The organohydrogenpolysiloxane of component (c) has a hydrogen atom (that is, a Si—H group) bonded to a silicon atom in a molecule. 2 or more, preferably 3 or more of these Si-H groups exist in 1 molecule, and the position in the molecule | numerator of the said Si-H group may be either the molecular chain terminal, the molecular chain non-terminal, or both. do. The organohydrogenpolysiloxane may be linear or cyclic, and in any case, the organohydrogenpolysiloxane may contain a branched structure in its molecule.

In addition, (c) component may be used individually by 1 type or in combination of 2 or more types.

As a specific example of (c) component, the following average structural formulas (2)-(4):

R ² -Si (R ² ) _2- [OSi (R ² ) ₂ ] _b- [OSi (R ² ) (H)] _c -OSi (R ² ) ₂ -R ² (2)

H-Si (R ² ) _2- [OSi (R ² ) ₂ ] _b- [OSi (R ² ) (H)] _d -OSi (R ² ) ₂ -R ² (3)

H-Si (R ² ) _2- [OSi (R ² ) ₂ ] _b- [OSi (R ² ) (H)] _e -OSi (R ² ) ₂ -H (4)

(Wherein R ² is independently an unsubstituted or substituted monovalent hydrocarbon group having preferably 1 to 12 carbon atoms other than an alkenyl group, b, e are independently an integer of 0 or more, and c is an integer of 2 or more) And d is an integer of 1 or more), and an organohydrogenpolysiloxane is mentioned.

In the general formulas (2) to (4), the unsubstituted or substituted monovalent hydrocarbon group other than the alkenyl group represented by R ² has more preferably 1 to 10 carbon atoms, still more preferably 1 to 6 carbon atoms. . The unsubstituted or substituted monovalent hydrocarbon group other than the alkenyl group represented by said R <^2> is specifically the same as what was illustrated and demonstrated as group other than an alkenyl group in the term of the said (a) component, for example.

As for b, c, d, and e, the number in which the viscosity at 25 degrees C of organohydrogenpolysiloxane represented by said General formula (2)-(4) becomes 1,000 mm <2> / s or less, especially 300 mm <2> / s or less is preferable. Do.

The compounding quantity of (c) component needs to be an amount which becomes 0.3-50 mol of Si-H groups in the said (c) component per mol of alkenyl groups couple | bonded with the silicon atom in (a) component, The said Si-H group is preferable. Is 0.5 to 30 mol, more preferably 0.8 to 20 mol, particularly preferably 1 to 5 mol. If the Si-H group is less than the amount of 0.3 mol, the vulcanization reaction may not proceed sufficiently. If the amount of the Si-H group is more than 50 mol, foaming may occur at the time of vulcanization.

(D) platinum group metal catalysts

The platinum group metal catalyst of the component (d) is a component for promoting the addition curing reaction of the alkenyl group bonded to the silicon atom in the component (a) and the Si—H group in the component (c). This platinum group metal catalyst should just be a well-known catalyst used for a hydrosilylation reaction, For example, Platinum group metal bodies, such as platinum (including platinum black), rhodium, palladium; H ₂ PtCl ₄ nH ₂ O, H ₂ PtCl ₆ nH ₂ O, NaHPtCl ₆ nH ₂ O, KHPtCl ₆ nH ₂ O, Na ₂ PtCl ₆ nH ₂ O, K ₂ PtCl ₄ nH ₂ O, Platinum chloride, chloroplatinic acid and chloroplatinic acid salts such as PtCl ₄ nH ₂ O, PtCl ₂ , Na ₂ HPtCl ₄ nH ₂ O (wherein n is an integer of 0 to 6, preferably 0 or 6), Alcohol-modified chloroplatinic acid, a complex of chloroplatinic acid and olefin, platinum group metals such as platinum black and palladium supported on a carrier such as alumina, silica, carbon, rhodium-olefin complex, chlorotris (triphenylphosphine) rhodium (i.e. Wilkinson catalyst), a platinum chloride, a chloroplatinic acid, or a chloroplatinate, and the complex of vinyl group containing siloxane, especially vinyl group containing cyclic siloxane, etc. are mentioned.

Although the compounding quantity of (d) component is sufficient as an effective amount as a catalyst, in the composition obtained, it is 0.1-1,000 ppm normally in mass conversion of a platinum group metal element with respect to the said (a) component, More preferably, it is 0.5-500 ppm, More Preferably it is 1.0-200 ppm. If the amount is too small, the composition will not be cured sufficiently. If the amount is too high, the platinum group metal catalyst is expensive and therefore uneconomical.

In addition, these (d) components may be used individually by 1 type, or may use 2 or more types together.

(E) antioxidant

When the sheet for thermocompression bonding is thermocompression-bonded to an anisotropically conductive adhesive agent, the oxidation control agent of (e) component has the effect | action which prevents the radical polymerization hardening type resin contained in the said adhesive agent from moving and hardening | curing in the said sheet | seat.

As an example of this antioxidant, Antioxidant added to polymeric resin, such as a hindered phenol and a hindered amine; Tocopherol compounds; Ascorbic acid compounds; Polyphenol compounds; Sulfur compounds; and the like.

Examples of the hindered phenol include butylhydroxytoluene, 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid, and the like.

Examples of the hindered amine include poly [(6-morpholino-s-triazine-2,4-diyl) [2,2,6,6-tetramethyl-4-piperidyl] imino] -hexamethylene [ (2,2,6,6-tetramethyl-4-piperidyl) imino] etc. are mentioned.

As a tocopherol compound, d-tocopherol, (beta) -tocopherol, (gamma) -tocopherol, (delta) -tocopherol, etc. are mentioned.

Ascorbic acid compounds include ascorbic acid, ascorbyl magnesium phosphate, ascorbyl tetrahexyldecanoic acid, ascorbic acid stearate and the like.

As a polyphenol compound, catechin, anthocyanin, flavone, isoflavone, flavan, flavanone, curcumin, etc. are mentioned, Preferably it is catechin.

Examples of the sulfur compound include polysulfidesilane.

The compounding quantity of (e) component needs to be 0.001-30 mass parts with respect to 100 mass parts of said (a) component in the composition obtained, Preferably it is 0.001-10 mass parts, More preferably, 0.01-5 mass parts, More preferably, it is 0.1-2 mass parts. When this compounding quantity is less than 0.001 mass part, the sheet for thermocompression bonding does not have a desired peeling durability, and when it exceeds 30 mass parts, the strength of the said sheet becomes inadequate.

In addition, (e) component may be used individually by 1 type or in combination of 2 or more types.

Other ingredients

You may mix | blend components other than said (a)-(e) component with the said composition in the range which does not impair the characteristic of a thermocompression bonding sheet. Specific examples thereof include improving the functions of the sheet for thermocompression bonding, such as a reaction inhibitor of an addition curing reaction, a reinforcing filler such as aerosol silica, a surface treatment agent of a thermally conductive filler, a pigment / dye for coloring, a flame retardant imparting agent, and an internal additive release agent. Various additives, a solvent, etc. for this are mentioned.

Preparation method

The said composition is prepared by kneading (a)-(e) component and the other component mix | blended according to the case. Although the order of the mixing is not particularly limited, it is preferable to first knead the components (a) and (b) before mixing, and then add and knead the components (c) to (e) and other components to be blended in some cases. Do. In addition, for kneading, a kneader, a pressurized kneader, a Banbury mixer, a biaxial roll, a triaxial roll, and a mixer used for kneading powder and liquid may be used.

About the thermocompression sheet

·shape

The thickness of the layer containing the hardened | cured material of the composition which has the said (a)-(e) component which comprises the sheet | seat for thermocompression bonding is 10-10,000 micrometers normally, Preferably it is 30-1,000 micrometers, More preferably, 50-500 micrometers. When this range is satisfied, the strength of the thermocompression bonding sheet is satisfactory, and there is no fear of breaking, and the curing of the adhesive is satisfactory because the temperature of the heat-compression bonding tool is sufficiently transmitted to the anisotropic conductive adhesive.

Manufacturing method

About the manufacturing method of the sheet | seat A for thermocompression bonding, the case where it becomes only the layer containing the hardened | cured material of the said composition is demonstrated as an example. In this case, the sheet for thermocompression bonding of this invention can be produced by hardening | curing, after shape | molding the said composition to a sheet form as needed. Although the said molding can be performed by press molding, calender molding, extrusion molding, the coating molding which coats the said composition (containing a solvent) to base materials, such as PET film, etc., you may carry out by methods other than these, for example. . In addition, at the time of the said shaping | molding, what is necessary is just to adjust the usage-amount of a composition so that the thickness of the layer containing the hardened | cured material of the said composition may become the said range.

<Heat Press Sheet B>

The sheet B for thermocompression bonding of this invention is a base material layer containing the hardened | cured material of the composition (henceforth "the composition for base material layer formation") containing the following (A)-(C) component, and one of this layer It is a sheet for thermocompression bonding which is formed in the surface or both surfaces, and has a mold release layer containing the hardened | cured material of the composition (henceforth "the composition for mold release layer formation") containing the following (i)-(v) component. Moreover, although the composition for base material layer formation can be made into arbitrary hardening types, for example, addition reaction hardening type, radical reaction hardening type, etc., Preferably it is an addition reaction hardening type.

The detail of each component is as follows.

About the composition for base layer formation

(A) organopolysiloxane

The organopolysiloxane of the component (A) is not particularly limited as long as it can be a base polymer of silicone rubber, but the same as those described and exemplified as the organopolysiloxane of the component (a) of the above-mentioned thermocompression bonding sheet A Is illustrated.

In addition, (A) component may be used individually by 1 type or in combination of 2 or more types.

(B) thermally conductive filler

The thermally conductive filler of (B) component has the effect | action which improves the thermal conductivity of the sheet | seat for thermocompression bonding. This thermally conductive filler is as having demonstrated and demonstrated as the thermally conductive filler of (b) component of the above-mentioned thermocompression-bonding sheet A.

The compounding quantity of (B) component needs to be 20-2,000 mass parts with respect to 100 mass parts of said (A) component in the composition obtained, Preferably it is 30-1,500 mass parts, More preferably, it is 50-1,000 mass It is wealth. When the compounding amount is less than 20 parts by mass, the sheet for thermocompression bonding is not to have a desired thermal conductivity, and heat applied to the anisotropic conductive adhesive is insufficient, and when the amount exceeds 2,000 parts by mass, the sheet is weak. Hardness becomes too high, and uniform crimping becomes difficult.

In addition, (B) component may be used individually by 1 type or in combination of 2 or more types.

(C) curing agent

The hardening | curing agent of (C) component is a component which contributes to hardening of the composition for base material layer forming. As (C) component, you may select from an well-known hardening | curing agent normally used for hardening of a silicone rubber composition suitably according to the hardening aspect of a composition, and use an effective amount. In addition, in all the hardening aspects, (C) component may be used individually by 1 type or in combination of 2 or more types.

When the composition for base layer formation is a radical reaction hardening type, an organic peroxide is used. Specific examples thereof include di-t-butyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide, and the like.

In this case, the compounding quantity of (C) component is 0.01-10 mass parts normally with respect to 100 mass parts of said (A) components, Preferably it is 0.05-5 mass parts, More preferably, it is 0.1-3 mass parts.

When the composition for base layer formation is an addition reaction curing type, an organohydrogenpolysiloxane having a hydrogen atom bonded to a silicon atom and a platinum group metal catalyst are used.

As this organohydrogenpolysiloxane, it is as having demonstrated and illustrated as organohydrogenpolysiloxane of (c) component of the above-mentioned thermocompression-bonding sheet A.

In this case, the compounding quantity of the said organohydrogenpolysiloxane is the amount which Si-H group in said organohydrogenpolysiloxane becomes 0.3-50 mol with respect to 1 mol of alkenyl groups couple | bonded with the silicon atom in (A) component, Preferably 0.5-30 mol, More preferably, it is the amount which becomes 0.8-20 mol, Especially preferably, it is 1-5 mol.

In addition, as a platinum group metal catalyst, it is as having demonstrated and demonstrated as platinum group metal catalyst of (d) component of the above-mentioned thermocompression-bonding sheet A.

Although the compounding quantity of the said platinum group metal catalyst is sufficient as an effective amount as a catalyst, in the composition obtained, it is 0.1-1,000 ppm normally in mass conversion of a platinum group metal element with respect to the said (A) component, Preferably it is 0.5-500 ppm, More Preferably it is 1.0-200 ppm. If the amount is too small, the composition cannot be cured sufficiently. If the amount is too high, the platinum group metal catalyst is expensive, and thus it is uneconomical.

Other ingredients

You may mix | blend components other than said (A)-(C) component with the said composition in the range which does not impair the characteristic of the thermocompression bonding sheet. As the specific example, it is as having demonstrated and demonstrated as another component of the sheet | seat A for thermal compression mentioned above. Moreover, you may mix | blend the antioxidant (D).

(D) When antioxidant is crimped | bonded by the anisotropically conductive adhesive agent, the antioxidant has a function which prevents radical polymerization hardening type resin contained in this adhesive agent from moving and hardening | curing in the said sheet | seat. This (D) antioxidant is as having demonstrated and illustrated as antioxidant of (e) component in the above-mentioned thermocompression-bonding sheet A.

The compounding quantity of (D) antioxidant is 0.001-30 mass parts with respect to 100 mass parts of said (A) component in the composition obtained, More preferably, it is 0.001-10 mass parts, Especially preferably, 0.01-5 It is mass parts, More preferably, it is 0.1-2 mass parts. When this compounding quantity exceeds 30 mass parts, the intensity | strength of the said sheet | seat becomes inadequate.

In addition, (D) antioxidant may be used individually by 1 type, or may use 2 or more types together.

Preparation method

The said base material layer forming composition is prepared by kneading (A)-(C) component and the other component mix | blended according to the case. Although the order of the compounding is not particularly limited, it is preferable to first mix the component (A) and the component (B) in advance, and then add and knead the component (C) and other components to be blended in some cases. In addition, for kneading, a kneader, a pressurized kneader, a Banbury mixer, a biaxial roll, a triaxial roll, and a mixer used for kneading powder and liquid may be used.

About the composition for forming a release layer

(I) organopolysiloxanes having two or more alkenyl groups bonded to silicon atoms

The organopolysiloxane which has the alkenyl group of (iii) component is the organopolysiloxane of the same kind as what was demonstrated as organopolysiloxane of (a) component in the above-mentioned thermocompression-bonding sheet A. Therefore, the description here is omitted.

(Ii) organohydrogenpolysiloxanes having two or more hydrogen atoms bonded to silicon atoms

The organohydrogenpolysiloxane of the component (ii) is the same as that described as the organohydrogenpolysiloxane of the component (c) in the above-mentioned thermocompression bonding sheet A. Therefore, the description here is omitted. The compounding quantity with respect to (iii) component of (ii) component is the same as the compounding quantity with respect to (a) component of above-mentioned (c) component.

Platinum group metal catalyst

The platinum group metal catalyst of the component (iii) is a component for promoting the addition curing reaction of the alkenyl group bonded to the silicon atom in the component (iii) and the Si—H group in the component (ii). This platinum group metal catalyst is the same as that described as the platinum group metal catalyst of (d) component in the above-mentioned thermocompression bonding sheet A, and the compounding quantity is also as having demonstrated about the case of (d) component.

(Ⅳ) antioxidant

The antioxidant of the component (i) has a function of preventing the radical polymerization curable resin contained in the adhesive from migrating into the sheet when the sheet for thermal compression is pressed against the anisotropic conductive adhesive. This antioxidant is as having demonstrated and illustrated as antioxidant of (e) component in the above-mentioned thermocompression-bonding sheet A.

The compounding quantity of (iii) component needs to be 0.001-30 mass parts with respect to 100 mass parts of said (iv) components in the composition obtained, Preferably it is 0.005-20 mass parts, More preferably, 0.01-10 mass parts to be. When this compounding quantity is less than 0.001 mass part, the sheet for thermocompression bonding does not have a desired peeling durability, and when it exceeds 30 mass parts, the strength of the said sheet becomes inadequate.

In addition, a component (i) may be used individually by 1 type, or may use 2 or more types together.

Other ingredients

You may mix | blend components other than said (i)-(i) component with the said composition in the range which does not impair the characteristic of a thermocompression bonding sheet. As the specific example, the thermally conductive filler demonstrated by the above-mentioned thermocompression-bonding sheet A, and other components are mentioned.

When mix | blending a thermally conductive filler, the compounding quantity becomes like this. Preferably it is 20-2,000 mass parts, More preferably, it is 30-1,500 mass parts, More preferably, 50-1,000 with respect to 100 mass parts of said (iv) components. It is a mass part.

Preparation method

The composition for base layer formation is prepared by kneading the components (i) to (iii) and other components blended in some cases. The order of the compounding is not particularly limited. In addition, for kneading, a kneader, a pressurized kneader, a Banbury mixer, a biaxial roll, a triaxial roll, and a mixer used for kneading powder and liquid may be used.

About the thermocompression sheet

·shape

The thickness of the base material layer constituting the sheet B for thermocompression bonding is usually 10 to 10,000 m, preferably 30 to 1,000 m, more preferably 50 to 500 m, and the thickness of the release layer is usually 0.1 to 200 micrometers, Preferably it is 0.5-100 micrometers, More preferably, it is 1-50 micrometers. When this range is satisfied, the strength of the thermocompression bonding sheet becomes satisfactory, and there is no fear of breaking, and the curing of the adhesive becomes satisfactory because the temperature of the heat-compression bonding tool is sufficiently transmitted to the anisotropic conductive adhesive.

Manufacturing method

The manufacturing method of the sheet B for thermocompression bonding is demonstrated as an example including the said base material layer and the said release layer. In this case, the sheet for thermocompression bonding of the present invention is usually produced by forming the release layer on one side or both sides of the base layer.

Specifically, first, the composition for forming the base material layer is molded into a sheet as needed, and then the base material layer is produced by curing. The molding may be carried out by press molding, calender molding, extrusion molding, coating molding in which the composition (including solvent) is coated on a substrate such as a PET film, and the like. You may also At the time of the said shaping | molding, what is necessary is just to adjust the usage-amount of a composition so that the thickness of a base material layer may become the said range.

The release layer may be laminated by applying the composition for forming a release layer directly onto one surface of the substrate layer or applying the composition on a release paper, a release film, or the like once, and then transferring the composition onto the substrate layer, followed by curing the composition. Can be. Moreover, you may laminate by methods other than these. The application may be performed using, for example, a comma coater, knife coater, gravure coater, dip coater, or the like. In the case of the said application | coating, what is necessary is just to adjust the usage-amount of a composition so that the thickness of a mold release layer may become the said range. In addition, when forming a mold release layer on both surfaces of a base material layer, what is necessary is just to repeat application | coating of the composition for mold release layer formation mentioned above.

·Usage

The sheets A and B for thermocompression bonding are, for example, when manufacturing a laminate or a flexible printed circuit board, or when the electrodes connected to a flat display panel or the like and the lead electrodes of the flexible printed circuit board are electrically and mechanically connected through an anisotropic conductive adhesive. Can be used. It is preferable to use it for thermocompression bonding especially when the said adhesive agent is an anisotropically conductive adhesive containing radical polymerization hardening type resin.

<Example>

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, these do not limit this invention at all. In addition, "Me" represents a methyl group.

<Example 1>

It has a BET specific surface area of 65 m 2 / g, containing 99.85 mol% of dimethylsiloxane units and 0.15 mol% of methylvinylsiloxane units, and 100 parts by mass of methylvinylpolysiloxane having an average degree of polymerization of 8,000 in which both ends of the molecular chain are sealed with trimethylsilyl groups. 50 parts by mass of acetylene black (trade name: Denka Black Powder Co., Ltd., Denki Kagaku Kogyo Co., Ltd.) and fumed silica having a BET specific surface area of 120 m 2 / g (trade name: Aerosil R-972, Nippon Aerosil (Manufactured) 5 parts by mass was blended and kneaded until uniform with a biaxial roll to prepare a mixture a.

0.2 mass part of 2-ethylhexanol solutions (platinum metal amount: 2 mass%) of chloroplatinic acid, 0.2 mass part of ethynylcyclohexanol which are reaction inhibitors, and the following average structural formulas (5) to this mixture a:

Me ₃ Si- (OMe ₂ Si) _18- [O (H) MeSi] ₂₀ -OSiMe ₃ (5)

1.0 parts by mass of methylhydrogenpolysiloxane and 5 parts by mass of butylhydroxytoluene were blended and kneaded until uniform with a biaxial roll to prepare a silicone rubber compound.

The silicone rubber compound is discharged by dividing the silicone rubber compound on a substrate of 100 μm thick PET film so as to have a thickness of 200 μm, left to cure for 5 minutes in an atmosphere of 160 ° C., and then thermally compressed. Was produced.

<Example 2>

A thermocompression-bonding sheet 2 was prepared in the same manner as in Example 1 except that 5 parts by mass of d-δ-tocopherol (trade name: Imix D, manufactured by ESA Co., Ltd.) was used instead of 5 parts by mass of butylhydroxytoluene. Produced.

<Example 3>

In the same manner as in Example 1, except that 5 parts by mass of ascorbic acid stearate ester was used in place of 5 parts by mass of butylhydroxytoluene, a sheet 3 for thermal compression was produced.

<Example 4>

The following structural formula (6) instead of 5 parts by mass of butylhydroxytoluene in Example 1:

[(MeO) ₃ Si- (CH ₂ ) ₃ -S _4- (CH ₂ ) ₂ -O-CH _2- ] ₂ (6)

A thermocompression bonding sheet 4 was produced in the same manner as in Example 1 except that 1 part by mass of polysulfidesilane represented by.

Comparative Example 1

Except not having added 5 parts by mass of butylhydroxytoluene in Example 1, a thermally crimped sheet C1 was produced in the same manner as in Example 1.

Comparative Example 2

A thermocompression-bonding sheet C2 was produced in the same manner as in Example 1 except that instead of 5 parts by mass of butylhydroxytoluene in Example 1, 1 part by mass of cerium oxide was used.

Example 5

It has a BET specific surface area of 65 m 2 / g, containing 99.85 mol% of dimethylsiloxane units and 0.15 mol% of methylvinylsiloxane units, and 100 parts by mass of methylvinylpolysiloxane having an average degree of polymerization of 8,000 in which both ends of the molecular chain are sealed with trimethylsilyl groups. 50 parts by mass of acetylene black (trade name: Denka Black Powder Co., Ltd., Denki Kagaku Kogyo Co., Ltd.) and fumed silica having a BET specific surface area of 120 m 2 / g (trade name: Aerosil R-972, Nippon Aerosil (Manufactured) 5 parts by mass was blended and kneaded until uniform with a biaxial roll, to prepare a mixture A.

0.2 mass part of 2-ethylhexanol solutions (platinum metal amount: 2 mass%) of chloroplatinic acid, 0.2 mass part of ethynyl cyclohexanol which are reaction inhibitors, and methyl represented by the said average structural formula (5) to this mixture A 1.0 mass part of hydrogen polysiloxane was mix | blended, it knead | mixed until it became uniform with a biaxial roll, and the silicone rubber compound used as the base material layer of a composite sheet was prepared.

The base material layer was produced by dividing this silicone rubber compound on the base material of 100-micrometer-thick PET film so that it might become 200 micrometers using a calender molding machine, and leaving it to cure for 5 minutes in 160 degreeC atmosphere. .

Separately, fumed silica having a BET specific surface area of 300 m 2 / g in 100 parts by mass of dimethylpolysiloxane having a viscosity of 30,000 mm 2 / s at 25 ° C. in which both ends of the molecular chain are sealed with a vinyl group (trade name: Aero 5 mass parts of quality 300, Nippon Aerosil Co., Ltd.), 8 mass parts of hexamethyldisilazane, and 2 mass parts of water are mix | blended, and it mixes in kneader for 1 hour at room temperature, and at 160 degreeC for 4 hours. The base compound was prepared by cooling to room temperature.

80 parts by mass of a dimethylpolysiloxane having a viscosity of 600 mm 2 / s at 25 ° C. in which both ends of the molecular chain are blocked with a vinyl group in the base compound (the amount of the dimethylpolysiloxane as the component VII). The sum total of these (iii) components is 100 mass parts), 0.1 mass part of 2-ethylhexanol solutions (platinum metal amount: 2 mass%) of chloroplatinic acid, and 0.1 mass part of ethynyl cyclohexanol which are reaction inhibitors, are mix | blended, , Mix until uniform, then mix 2.5 parts by mass of methylhydrogenpolysiloxane represented by the above average structural formula (5), mix until uniform, and finally mix 5 parts by mass of butylhydroxytoluene, Mix until the mixture B was prepared.

On the base material layer, the mixture B was applied so as to have a thickness of 30 μm using a knife coater, and then left to stand for 5 minutes in an atmosphere at 150 ° C. to cure the mixture B, thereby laminating a release layer to heat the sheet 5. Was produced.

<Example 6>

A thermocompression bonding sheet 6 was prepared in the same manner as in Example 5 except that 5 parts by mass of d-δ-tocopherol (trade name: Imix D, manufactured by ESA Co., Ltd.) was used instead of 5 parts by mass of butylhydroxytoluene in Example 5. Produced.

<Example 7>

In the same manner as in Example 5, except that 5 parts by mass of ascorbic acid stearate ester was used in place of 5 parts by mass of butylhydroxytoluene, a sheet 7 for thermal compression was produced.

<Example 8>

A thermosetting sheet 8 was produced in the same manner as in Example 5 except that in Example 5 1 mass part of polysulfidesilane represented by the following structural formula (6) was used instead of 5 mass parts of butylhydroxytoluene.

Comparative Example 3

Except not having added 5 mass parts of butylhydroxytoluene in Example 5, it carried out similarly to Example 5, and produced the sheet | seat C3 for thermocompression bonding.

<Comparative Example 4>

A thermocompression-bonding sheet C4 was produced in the same manner as in Example 5 except that 1 part by mass of cerium oxide was used instead of 5 parts by mass of butylhydroxytoluene in Example 5.

Peeling durability test

The test which evaluates the peeling durability with respect to the anisotropic conductive adhesive containing radical polymerization hardening type resin of the thermocompression bonding sheet obtained in Examples 1-8 or Comparative Examples 1-4 was done. That is, an anisotropic conductive adhesive (trade name: AC-9051AR-35, manufactured by Hitachi Kasei Kogyo Co., Ltd.) is directly applied to the bottom surface of the thermal compression sheet to form an adhesive layer, and the adhesive layer has a thickness of 100 μm. The polyimide film was arrange | positioned and the laminated body was produced. Next, this laminated body was crimped | bonded by applying the pressure of 4 Mpa for 20 second with the crimping tool heated at 240 degreeC from upper side (sheet side for thermocompression bonding). Thereafter, the pressed laminate was peeled off at the boundary between the sheet for thermal compression and the anisotropic conductive adhesive. The above process was made into one set.

The above steps were repeated in the same manner, except that the exfoliated thermocompression sheet was reused and the anisotropic conductive adhesive and the polyimide film were replaced with new ones. The number of repetitions until the anisotropic conductive adhesive adhered to the sheet for thermocompression bonding at the time of the peeling was measured. The results are shown in Tables 1 and 2 below.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Collection (times) until anisotropic conductive adhesive adheres 35 30 32 24 11 12

Example 5 Example 6 Example 7 Example 8 Comparative Example 3 Comparative Example 4 Collection (times) until anisotropic conductive adhesive adheres 60 51 56 50 24 21

Even if the sheet for thermocompression bonding of the present invention is used for thermocompression bonding of an anisotropic conductive adhesive containing a radical polymerization curable resin, the sheet deteriorates slowly and can be used repeatedly for a longer period of time, that is, excellent in peeling durability. . Especially in embodiment which has the said base material layer and a release layer, the said peeling durability becomes remarkably excellent. Therefore, by using these sheets for thermocompression bonding of the present invention, it contributes to the improvement of the work efficiency and the cost reduction of the thermocompression bonding step.

Claims (8)

(a) organopolysiloxane having two or more alkenyl groups bonded to a silicon atom: 100 parts by mass, (b) thermally conductive filler: 20 to 2,000 parts by mass, (c) organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms: per hydrogen of alkenyl groups bonded to the silicon atoms in the component (a), the hydrogen atoms bonded to the silicon atoms in the component (c) from 0.3 to 50 Molar volume, (d) platinum group metal catalysts: an effective amount, and (e) Antioxidant: 0.001-30 mass parts The sheet for thermocompression bonding which has a layer containing the hardened | cured material of the composition containing them. The sheet according to claim 1, wherein the layer containing the cured product has a thickness of 10 to 10,000 m. (A) organopolysiloxane: 100 parts by mass, (B) thermally conductive filler: 20 to 2,000 parts by mass, and (C) curing agent: effective amount It is formed in the base material layer containing the hardened | cured material of the composition containing this, and one side or both sides of this layer, (Iii) organopolysiloxane having two or more alkenyl groups bonded to a silicon atom: 100 parts by mass, (Ii) organohydrogenpolysiloxanes having two or more hydrogen atoms bonded to silicon atoms: 0.3 to 50 hydrogen atoms bonded to the silicon atoms in the component (ii) per one mole of alkenyl group bonded to the silicon atom in the component (iii) Molar volume, (Iii) a platinum group metal catalyst: an effective amount, and (Iii) Antioxidant: 0.001-30 mass parts The sheet for thermocompression bonding which has a mold release layer containing the hardened | cured material of the composition containing. The sheet | seat of Claim 3 in which the said composition for base material layer formation contains (D) antioxidant further. The sheet according to claim 3 or 4, wherein the base layer has a thickness of 10 to 10,000 µm, and the release layer has a thickness of 0.1 to 200 µm. The said (e) antioxidant, the said (D) antioxidant, and the said (iv) antioxidant are independently a hindered phenol, a hindered amine, a tocopherol compound, The said any one of Claims 1-4. At least one sheet selected from the group consisting of ascorbic acid compounds, polyphenol compounds, and sulfur compounds. The sheet according to claim 6, wherein the polyphenol compound is catechin. The sheet according to any one of claims 1 to 4, which is used for thermocompression bonding of an anisotropic conductive adhesive containing a radical polymerization curable resin.