TWI685531B - Acrylic thermal conductive composition and thermal conductive sheet - Google Patents

Abstract

The present invention provides an acrylic thermally conductive composition and a thermally conductive sheet that can form a sheet that can achieve low outgassing and excellent flexibility. The acrylic thermal conductive composition contains: monofunctional (meth)acrylate, polyfunctional (meth)acrylate, photopolymerization initiator, thermally conductive particles, plasticizer and thiol compound, the plasticizer is selected by itself At least one of diacid ester, pimelic acid ester, supinate ester, azelaic acid ester and sebacic acid ester. In addition, the thiol compound is a multifunctional thiol. The thermally conductive sheet has a thermally conductive resin layer (11) formed by photohardening an acrylic thermally conductive composition.

Description

Acrylic thermal conductive composition and thermal conductive sheet

The present invention relates to an acrylic heat conductive composition and a heat conductive sheet that can be used for heat dissipation measures for electronic parts and the like.

In recent years, with the improvement of the performance of electronic equipment, heat dissipation measures for electronic parts and the like have been required. In addition, precision devices such as hard disk devices and laser devices also require measures for heat dissipation and measures for air release from components.

For example, in order to increase the amount of memory, the hard disk device must increase the density of the scanning head, and in order to increase the access speed, a motor must be used to rotate the recording medium at high speed. Therefore, it is necessary to efficiently dissipate the heat generated by the motor, and it is necessary to avoid the attachment of outgassing to the scanning head and the like.

Regarding the thermally conductive sheet, from the viewpoint of heat resistance, flexibility, etc., polysiloxane resins are mostly used. However, polysiloxane resins generate a large amount of low-molecular siloxane gas, which may cause contact obstacles.

Therefore, a non-polysiloxane-based acrylic thermal conductive sheet has been developed (for example, refer to Patent Document 1). However, previous acrylic thermal conductive sheets have concerns about the release of multiple outgassings other than siloxane gas. In addition, the previous acrylic thermal conductive sheet impairs flexibility and is difficult To obtain excellent adhesion to the heating element or heat sink.

[Patent Document 1] Japanese Patent Application Publication No. 2007-123624

The present invention was made in view of the foregoing circumstances, and its first object is to provide an acrylic heat conductive composition and a heat conductive sheet that can achieve low outgassing. In addition, the second object of the present invention is to provide an acrylic heat conductive composition capable of forming a sheet having excellent flexibility and a heat conductive sheet.

After intensive studies, the inventors found that low outgassing can be achieved by using specific dicarboxylic acid esters as plasticizers. In addition, after intensive studies, the inventors found that excellent flexibility can be obtained by using a specific dicarboxylic acid ester as a plasticizer and using a thiol compound.

That is, the acrylic thermal conductive composition of the first invention is characterized by containing a monofunctional (meth)acrylate, a multifunctional (meth)acrylate, a photopolymerization initiator, thermally conductive particles, a plasticizer, and sulfur For the alcohol compound, the plasticizer is at least one selected from the group consisting of adipic acid ester, pimelic acid ester, supranate acid ester, azelaic acid ester and sebacic acid ester.

Furthermore, the acrylic thermal conductive composition of the second invention is characterized by containing a monofunctional (meth)acrylate, a polyfunctional (meth)acrylate, a photopolymerization initiator, thermally conductive particles, a plasticizer, and sulfur For the alcohol compound, the plasticizer is at least one selected from the group consisting of adipic acid ester, pimelic acid ester, supranate ester, azelaic acid ester, and sebacic acid ester, and the thiol compound is a multifunctional thiol.

In addition, the thermally conductive sheet of the first invention is characterized by having a thermally conductive resin layer obtained by photohardening an acrylic thermally conductive composition. The acrylic thermally conductive composition contains a monofunctional (meth)acrylate and a multifunctional (meth) ) Acrylic ester, photopolymerization initiator, thermally conductive particles, plasticizer, and thiol compound, the plasticizer is selected from adipic acid ester, pimelic acid ester, suprameric acid ester, azelaic acid ester, sebacic acid At least one of the acid esters.

In addition, the thermally conductive sheet of the second invention is characterized by having a thermally conductive resin layer obtained by photohardening an acrylic thermally conductive composition. The acrylic thermally conductive composition contains a monofunctional (meth)acrylate and a polyfunctional (meth) ) Acrylic ester, photopolymerization initiator, thermally conductive particles, plasticizer, and thiol compound, the plasticizer is selected from adipic acid ester, pimelic acid ester, suprameric acid ester, azelaic acid ester, sebacic acid At least one of the acid esters, and the thiol compound is a polyfunctional thiol.

According to the first invention, the plasticizer is at least one selected from the group consisting of adipic acid esters, pimelic acid esters, suppositoric acid esters, azelaic acid esters, and sebacic acid esters. Therefore, the generation of outgassing can be suppressed. Furthermore, according to the second invention, the thiol compound is a multifunctional thiol, and therefore excellent flexibility can be obtained.

11‧‧‧ Thermal conductive resin layer

12‧‧‧Support resin layer

13‧‧‧ peeling film

1 is a cross-sectional view showing an example of a thermally conductive sheet according to an embodiment of the present invention.

Hereinafter, the embodiments of the present invention will be described in detail in the following order while referring to the drawings.

1. Acrylic thermal conductive composition

2. Thermal conductive sheet

3. Examples

<1. Acrylic thermal conductive composition>

The acrylic thermal conductive composition shown as one embodiment of the present invention contains: (A) monofunctional (meth)acrylate, (B) multifunctional (meth)acrylate, (C) photopolymerization initiator, ( D) Thermally conductive particles, (E) plasticizer, and (F) thiol compound, (E) plasticizer is selected from adipic acid ester, pimelic acid ester, supranate ester, azelaic acid ester, sebacic acid At least one of the acid esters. In addition, in the present specification, the term "(meth)acrylate" means including acrylate and methacrylate.

[(A) Monofunctional (meth)acrylate]

The monofunctional (meth)acrylate is not particularly limited, and from the viewpoint of low outgassing, alkyl (meth)acrylate having a linear or branched alkyl group is preferably used. Examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, (meth) Group) n-butyl acrylate, second butyl (meth) acrylate, third butyl (meth) acrylate, isobutyl (meth) acrylate, n-pentyl (meth) acrylate, (meth) acrylic acid Isoamyl ester, n-hexyl (meth)acrylate, cyclohexyl acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, (meth)acrylic acid 2 -Ethylhexyl ester, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-dodecyl (meth)acrylate Alkyl esters, isomyristyl (meth)acrylate, n-tridecyl (meth)acrylate, n-tetradecyl (meth)acrylate, n-stearyl (meth)acrylate, (A Group) isostearyl acrylate, n-lauryl (meth) acrylate, etc., one or two of these can be used on. Among these, from the viewpoint of imparting flexibility, alkyl (meth)acrylate having a linear or branched alkyl group having 8 to 18 carbon atoms is preferably used, and (meth)acrylic acid can be preferably used 2-ethylhexyl ester, n-dodecyl (meth)acrylate, isostearyl (meth)acrylate.

[(B) Multifunctional (meth)acrylate]

Examples of multifunctional (meth)acrylates include 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and neopentyl glycol di(meth)acrylate. Meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene diacrylate Alcohol di(meth)acrylate, propylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate and other bifunctional (meth)acrylate; trimethylol Propane tri (meth) acrylate, neopentaerythritol tri (meth) acrylate, tri (acryloxyethyl) isocyanurate, di-trimethylolpropane tetra (meth) acrylate Esters, neopentaerythritol tetra (meth) acrylate, di-pentaerythritol monohydroxy penta (meth) acrylate, di-pentaerythritol hexa (meth) acrylate, etc. with more than 3 functions (meth) Acrylic esters can use one or more of these. Among these, from the viewpoint of imparting flexibility, at least one of polyethylene glycol di(meth)acrylate or polypropylene glycol di(meth)acrylate is preferably used.

Moreover, it is preferable to use a heterogeneous polymerizable monomer having two or more different polymerizable functional groups in the same molecule as the multifunctional (meth)acrylate. Examples of radical polymerizable groups include (meth)acryloyl groups, vinyl groups, allyl groups, styryl groups, acrylate groups, and methacrylate groups. Examples of cationic polymerizable groups include ethylene groups. Ether group, epoxy group, oxetanyl group, epoxypropyl group, etc. Among these heterogeneous polymerizable monomers, it is preferable to use a monomer having a (meth)acryloyl group and a vinyl ether group in the same molecule from the viewpoint of curability.

As a monomer having (meth)acryloyl and vinyl ether groups in the same molecule, for example Examples include: 2-(2-vinyloxyethoxy)ethyl (meth)acrylate, 2-vinyloxyethyl (meth)acrylate, 3-vinyloxyethyl (meth)acrylate, (Meth)acrylic acid 2-vinyloxypropyl ester, (meth)acrylic acid 1-methyl-2-vinyloxyethyl ester, (meth)acrylic acid 4-vinyloxybutyl ester, (meth)acrylic acid 6 -Vinyloxyhexyl, 4-vinyloxycyclohexyl (meth)acrylate, 4-vinyloxymethylcyclohexylmethyl (meth)acrylate, 2-(2-vinyloxy) (meth)acrylate Isopropyloxy)propyl ester, 2-(2-(2-vinyloxyethoxy)ethoxy}ethyl (meth)acrylate, etc., one or more of these can be used. Among these, from the viewpoint of low outgassing, 2-(2-vinyloxyethoxy)ethyl (meth)acrylate is preferably used.

In addition, the content of the polyfunctional (meth)acrylate in the acrylic heat conductive composition is 1 mass with respect to 100 mass parts of the monofunctional (meth)acrylate from the viewpoint of flexibility or low outgassing. It is more than 50 parts by mass, preferably 3 parts by mass or more and 15 parts by mass or less.

[(C) Photopolymerization initiator]

Examples of the photopolymerization initiator include: benzophenone series, benzoin series, benzoin alkyl ether series, benzophenone dimethylketal series, α-hydroxyketone series, and oxyacetyl group. For the phosphine series, one or more of these can be used. Among these, from the viewpoint of achieving smooth photohardening, it is preferable to use at least one of a acetylphosphine oxide system or an α-hydroxyketone system.

As the phosphine oxide-based photopolymerization initiator, 2,4,6-trimethylbenzyl diphenyl phosphine oxide, bis(2,4,6-trimethyl benzoyl phenyl) -Phenylphosphine oxide, bis(2,6-dimethoxybenzyl)-2,4,4-trimethyl-pentylphosphine oxide, etc.

Examples of the α-hydroxyketone-based photopolymerization initiator include oligo[2-hydroxy-2-methyl-1-{4-(1-methylvinyl)phenyl}]acetone and 1-hydroxy- Cyclohexyl-phenyl- Ketone, 2-hydroxy-2-methyl-1-phenyl-propane-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1 -Propane-1-one, 2-hydroxy-1-4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl-2-methyl-propane-1-one Wait.

The content of the photopolymerization initiator in the acrylic thermal conductive composition is 0.05 parts by mass or more and 5.0 parts by mass relative to 100 parts by mass of the monofunctional (meth)acrylate from the viewpoint of obtaining appropriate hardening physical properties. It is preferably 0.1 part by mass or more and 3.0 parts by mass or less.

[(D) Thermally conductive particles]

Examples of the thermally conductive particles include metal hydroxides such as aluminum hydroxide and magnesium hydroxide; metals such as aluminum, copper, and silver; metal oxides such as aluminum oxide and magnesium oxide; aluminum nitride, boron nitride, and silicon nitride Nitrogen compounds; carbon nanotubes, etc., one or more of these can be used. Among these, in terms of achieving good flame retardancy and insulation, it is preferable to use one or more kinds selected from aluminum hydroxide, aluminum oxide, aluminum nitride, and magnesium oxide.

In addition, in order to strengthen the interface with the resin or improve the dispersibility of the resin, a silane coupling agent, a titanate coupling agent, stearic acid, or the like may be used as the thermally conductive particles.

Further, the average particle diameter of the thermally conductive particles is preferably 0.5 μm or more and 100 μm or less, and particularly in terms of dispersibility and thermal conductivity, it is preferable to use small-diameter fillers having an average particle size of 3 μm or more and 20 μm or less. , And large-diameter fillers with an average particle size of 25 μm or more and 100 μm or less.

The content of the thermally conductive particles in the acrylic thermal conductive composition is 100 parts by mass or more and 2000 parts by mass or less, preferably 300 parts by mass or more and 1000 parts by mass or less with respect to 100 parts by mass of the monofunctional (meth)acrylate. . If the content of the thermally conductive particles is too small, it becomes difficult to sufficiently improve the thermal conductivity of the thermally conductive sheet, and if the content of the thermally conductive particles is too large, there is thermal conductivity The tendency of the softness of the sheet to decrease. In addition, when two types of thermally conductive fillers having different average particle diameters are used, the blending of the small-diameter filler and the large-diameter filler is preferably set to 15:85 to 90:10.

[(E) Plasticizer]

The plasticizer is selected from at least one of adipic acid ester, pimelic acid ester, supinate acid ester, azelaic acid ester and sebacic acid ester. Such dicarboxylic acid esters can be selected from adipic acid (HOOC-(CH ₂ ) ₄ -COOH), pimelic acid (HOOC-(CH ₂ ) ₅ -COOH) and suppository acid (HOOC- (CH ₂ ) ₆ -COOH), azelaic acid (HOOC-(CH ₂ ) ₇ -COOH), sebacic acid (HOOC-(CH ₂ ) ₈ -COOH) dicarboxylic acid and alcohol are obtained by esterification .

As the alcohol, either linear or branched may be used for esterification. Examples of linear alcohols include butanol, hexanol, octanol, and decanol. In addition, examples of branched alcohols include isobutanol, isoheptanol, 2-ethylhexanol, isooctyl alcohol, 3,5,5-trimethylhexanol, isononanol, and isodecyl alcohol. , Isoundecyl alcohol, isododecyl alcohol, isotridecyl alcohol, etc.

Among these, from the viewpoint of imparting flexibility, it is preferable to use one selected from the group consisting of adipic acid, pimelic acid, suppositoric acid, azelaic acid, and sebacic acid, and is selected from isodecyl alcohol and iso eleven A dicarboxylic acid ester obtained by esterifying one of alcohol, isododecyl alcohol, and isotridecanol.

Furthermore, among these dicarboxylic acid esters, one selected from adipic acid, pimelic acid, supramonic acid, azelaic acid, sebacic acid and isodecyl alcohol is preferably used from the viewpoint of low outgassing At least one of diisodecyl adipate, diisodecyl pimelate, diisodecyl pivalate, diisodecyl azelate, and diisodecyl sebacate is selected from the esterification.

The content of the plasticizer in the acrylic heat conductive composition is 30 parts by mass or more and 250 parts by mass or less, preferably 50 parts by mass or more and 150 parts by mass relative to 100 parts by mass of the monofunctional (meth)acrylate. the following. If the content of plasticizer is too small, the thermal conductive sheet will be damaged The flexibility becomes difficult to achieve low outgassing. If the content of the plasticizer is too much, the strength of the thermally conductive sheet may become insufficient.

[(F) Thiol compound]

、雙(2-甲基巰基甲基)硫化物、6-二丁基胺基-1,3,5-三

-2,4-二硫醇等2官能硫醇化合物；1,3,5-三(3-巰基丁氧基乙基)-1,3,5-三

-2,4,6(1H,3H,5H)-三酮、2-甲基-2-((3-巰基-1-側氧基丙基)-甲基)丙烷-1,3-二基雙(3-巰基丙酸酯)、三羥甲基丙烷三巰基丙酸酯、三羥甲基丙烷三硫甘醇、2,4,6-三巰基-對稱三

等3官能硫醇化合物；新戊四醇四(3-巰基丁酸酯)、新戊四醇四巰基乙酸酯、二新戊四醇四巰基乙酸酯、新戊四醇四巰基丙酸酯等4官能硫醇化合物；二新戊四醇五巰基乙酸酯等5官能硫醇化合物；二新戊四醇六巰基乙酸酯等6官能硫醇化合物等，可使用該等中之1種或2種以上。該等中，就賦予柔軟性之觀點而言，較佳使用2官能以上之多官能硫醇，更佳使用3官能硫醇或4官能硫醇中之至少任一種。 The thiol compound functions as a cross-linking agent, and imparts flexibility to the heat-conductive sheet. Examples of the thiol compound include monofunctional sulfur such as 1-pentanethiol, 1-hexylmercaptan, 1-heptanethiol, 1-octanethiol, 1-decanethiol, and 1-dodecanethiol. Alcohol compounds; 1,4-bis(3-mercaptobutaneoxy)butane, methanedithiol, methanedithiol, ethanedithiol, propanedithiol), 1,6-hexanedisulfide Alcohol, cyclohexane dithiol, 2,2-dimethylpropane-1,3-dithiol, 3,4-dimethoxybutane-1,2-dithiol, 2,3-dimercapto -1-propanol, 1,2-dimercapto-propyl methyl ether, 8-octanediol, butanediol dimercaptoacetate, ethylene glycol dimercaptoacetate, dipropylene glycol bis(2-mercapto Acetate), dipropylene glycol bis(3-mercaptoacetate), bis(mercaptomethyl)cyclohexane, 2-dicyclohexylamino-4,6-dimercapto-symmetric three

, Bis(2-methylmercaptomethyl) sulfide, 6-dibutylamino-1,3,5-tris

-2,4-dithiol and other bifunctional thiol compounds; 1,3,5-tris(3-mercaptobutoxyethyl)-1,3,5-tris

-2,4,6(1H,3H,5H)-trione, 2-methyl-2-((3-mercapto-1-oxopropyl)-methyl)propane-1,3-diyl Bis(3-mercaptopropionate), trimethylolpropane trimercaptopropionate, trimethylolpropane trithioglycol, 2,4,6-trimercapto-symmetric three

3 functional thiol compounds; neopentaerythritol tetra(3-mercaptobutyrate), neopentaerythritol tetramercaptoacetate, dipentaerythritol tetramercaptoacetate, neopentaerythritol tetramercaptopropionic acid 4-functional thiol compounds such as esters; 5-functional thiol compounds such as dipentaerythritol pentathioglycolate; 6-functional thiol compounds such as dipentaerythritol hexamercaptoacetate, etc. 1 of these can be used Species or more than two species. Among these, from the viewpoint of imparting flexibility, it is preferable to use a polyfunctional thiol having two or more functions, and it is more preferable to use at least any one of a trifunctional thiol or a tetrafunctional thiol.

The content of the thiol compound in the acrylic heat conductive composition is 0.1 parts by mass or more and 10.0 parts by mass or less relative to 100 parts by mass of the monofunctional (meth)acrylate from the viewpoint of imparting appropriate flexibility. It is preferably 2 parts by mass or more and 8 parts by mass or less.

[Other ingredients]

In addition, the acrylic thermal conductive composition may be blended with antioxidants, thermal degradation agents, flame retardants, colorants, etc. as other components.

Examples of the antioxidants include primary antioxidants that capture free radicals generated during thermal degradation, and secondary antioxidants that decompose peroxides generated during thermal degradation. These can be used alone or in combination 2 More than one species.

The primary antioxidant is used to trap peroxide radicals to prevent oxidative deterioration of the resin. A previously known primary antioxidant can be used, and a phenolic antioxidant can be preferably used. Examples of phenolic antioxidants include hexamethylenebis[(3,5-di-third-butyl-4-hydroxyphenyl)propionate amide], 4,4′-thiobis(6- Tert-butyl-m-cresol), 2,2'-methylenebis(4-methyl-6-third-butylphenol), 2,2'-methylenebis(4-ethyl-6 -Tert-butylphenol), bis[3,3-bis(4-hydroxy-3-tert-butylphenyl)butyric acid]diol ester, 2,2'-ethylenebis(4,6-di -Third butylphenol), 2,2'-ethylenebis (4-second butyl-6-third butylphenol), 1,1,3-tris (2-methyl-4-hydroxyl -5-tert-butylphenyl)butane, bis(2-tert-butyl-4-methyl-6-(2-hydroxy-3-tert-butyl-5-methylbenzyl)phenyl ] Terephthalate, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,3,5 -Tris[(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxyethyl]isocyanurate, tetra[methylene-3-(3,5-di-section Tributyl-4-hydroxyphenyl) propionate] methane, 2-tert-butyl-4-methyl-6-(2-propenyloxy-3-tert-butyl-5-methylbenzyl Group) phenol, 3,9-bis(1,1-dimethyl-2- {(3-Thirdbutyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, triethyl Diol bis[(3-third butyl-4-hydroxy-5-methylphenyl) propionate], n-octadecyl-3-(4'-hydroxy-3', 5'-di- Third butylphenyl) butane and so on. Among these, it is preferable to use n-octadecyl-3-(4'-hydroxy-3',5'-di-tert-butylphenyl)butane.

The content of the primary antioxidant in the acrylic thermal conductive composition is 0.5 with respect to 100 parts by mass of the monofunctional (meth)acrylate in terms of achieving the proper addition effect of the primary antioxidant and not inhibiting hardening. It is not less than 4.0 parts by mass and preferably not more than 4.0 parts by mass.

-10-磷雜菲-10-氧化物、2,2'-亞甲基雙(4-甲基-6-第三丁基苯基)-2-乙基己基亞磷酸酯、4-[3- [(2,4,8,10-四-第三丁基二苯并[d,f][1,3,2]二

磷環庚烷)-6-基氧基]丙基]-2-甲基-6-第三丁基苯酚等。其中，可較佳地列舉：4-[3-[(2,4,8,10-四-第三丁基二苯并[d,f][1,3,2]二

磷環庚烷(dioxaphosphepine))-6-基氧基]丙基]-2-甲基-6-第三丁基苯酚。 The secondary antioxidant is used to decompose hydroxide radicals to prevent the oxidative deterioration of the resin. A previously known secondary antioxidant can be used, and a phosphorus antioxidant can be preferably used. Examples of phosphorus-based antioxidants include trinonylphenyl phosphite, tris(2,4-di-tert-butylphenyl) phosphite, and tris[2-tert-butyl-4-phosphite (3-tert-butyl-4-hydroxy-5-methylphenylthio)-5-methylphenyl] ester, tridecyl phosphite, octyl diphenyl phosphite, diphosphite ( Decyl) monophenyl ester, di(tridecyl) neopentyl tetraphosphite diphosphite, distearyl neopentyl tetraphosphite diphosphite, di(nonylphenyl) neopentyl tetraphosphite diphosphite Ester, bis(2,4-di-tert-butylphenyl) neopentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl) neopentaerythritol Diphosphite, bis(2,4,6-tri-tert-butylphenyl) neopentaerythritol diphosphite, tetra(tridecyl)isopropylidenebiphenol diphosphite, tetra (Tridecyl)-4,4'-n-butylene bis(2-third butyl-5-methylphenol) diphosphite, hexa(tridecyl)-1,1,3-tri (2-methyl-4-hydroxy-5-tert-butylphenyl) butane triphosphite, tetra(2,4-di-tert-butylphenyl) biphenylene diphosphite, 9 ,10-dihydro-9-

-10-phosphaphenanthrene-10-oxide, 2,2'-methylenebis(4-methyl-6-third butylphenyl)-2-ethylhexylphosphite, 4-[3 -[(2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]di

Phosphocycloheptane)-6-yloxy]propyl]-2-methyl-6-tert-butylphenol and the like. Among them, preferably listed are: 4-[3-[(2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]di

Dioxaphosphepine-6-yloxy]propyl]-2-methyl-6-tert-butylphenol.

Regarding the content of the secondary antioxidant in the acrylic heat conductive composition, from the viewpoint of achieving an appropriate addition effect of the secondary antioxidant and preventing the hardening from being suppressed, with respect to 100 parts by mass of the monofunctional (meth)acrylate, It is 0.5 mass parts or more and 8.0 mass parts or less, Preferably it is 0.8 mass parts or more and 4.0 mass parts or less.

In addition, regarding the blending amount of the secondary antioxidant with respect to 100 parts by mass of the primary antioxidant, from the viewpoint of achieving an appropriate addition effect of the secondary antioxidant without producing hardening inhibition, it is preferably 50 to 270 parts by mass, It is more preferably 80 to 130 parts by mass.

The heat-resistant deterioration agent captures polymer radicals generated by the action of heat and oxygen, and maintains a stable free radical compound to prevent thermal deterioration of the acrylic thermally conductive composition caused by heat and oxygen. Examples of the thermal degradation resistance agent include 1,1-bis(2-hydroxy-3,5-di-third-pentylphenyl)methane acrylate monoester.

Regarding the content of the heat-resistant deterioration agent in the acrylic thermal conductive composition, from the viewpoint of achieving an appropriate addition effect of the heat-resistant deterioration agent and preventing the hardening from being suppressed, with respect to 100 parts by mass of the monofunctional (meth)acrylate, It is 0.1 mass part or more and 4.0 mass parts or less, Preferably it is 0.2 mass part or more and 3.0 mass parts or less.

In addition, regarding the blending amount of the thermal degradation agent with respect to 100 parts by mass of the primary antioxidant, from the viewpoint of achieving an appropriate addition effect of the anti-degradation agent without suppressing curing, it is preferably 10 parts by mass or more and 130 parts by mass. Less than 20 parts, more preferably 20 parts by mass or more and 100 parts by mass under.

The acrylic thermally conductive composition composed of the above-mentioned composition can be suppressed by containing at least one selected from adipic acid ester, pimelic acid ester, thromellitic acid ester, azelaic acid ester and sebacic acid ester as a plasticizer. The release of gas. In addition, the acrylic heat-conducting composition can impart excellent flexibility to the sheet by containing the above-mentioned plasticizer and containing a multifunctional thiol as a thiol compound.

<2. Thermal conductive sheet>

Next, a thermal conductive sheet using the acrylic thermal conductive composition will be described. The thermally conductive sheet shown as one embodiment of the present invention has a thermally conductive resin layer obtained by photohardening an acrylic thermally conductive composition. The acrylic thermally conductive composition contains: (A) a monofunctional (meth)acrylate, (B ) Multifunctional (meth)acrylate, (C) photopolymerization initiator, (D) thermally conductive particles, (E) plasticizer and (F) thiol compound, (E) plasticizer is selected from the two At least one of an acid ester, pimelic acid ester, suppositor acid ester, azelaic acid ester, and sebacic acid ester.

1 is a cross-sectional view showing an example of a thermally conductive sheet according to an embodiment of the present invention. The thermally conductive sheet includes a thermally conductive resin layer 11 obtained by photocuring the acrylic thermally conductive composition, and a supporting resin layer 12 that supports the thermally conductive resin layer 11. In addition, a peeling film 13 peeled off during use is attached to the surface of the thermally conductive resin layer 11.

The thermally conductive resin layer 11 is obtained by photocuring the acrylic thermal conductive composition described above. The thermal conductivity of the thermally conductive resin layer 11 is preferably 1.0 W/m. K above. In addition, the compression ratio of the thermally conductive resin layer 11 at a load of 1 kgf/cm ² is preferably 10% or more. The higher the compression rate, the easier it is to compress the thermally conductive resin layer, and the flexibility is excellent, and excellent adhesion to the heat generating body or the heat radiating body can be obtained.

Examples of the support resin layer 12 include polyethylene acetal resin, polyethylene butyral resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, and polyamine Thermoplastic resins such as polyester resin and polyvinyl alcohol resin. Among these, those obtained by adding a styrene-isoprene block copolymer to polyethylene acetal resin or polyethylene butyral resin can be preferably used. In addition, the support resin layer 12 may be colored black, white, or the like with a colorant.

As the release film 13, for example, PET (Polyethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methylpentene- 1. Poly-4-methylpentene-1), PTFE (Polytetrafluoroethylene, polytetrafluoroethylene), etc.

The thermally conductive sheet can be manufactured as follows, for example. First, a styrene-ethylene isoprene block copolymer is added to the polyethylene acetal resin to prepare a support resin composition, and the support resin composition is applied to a PET film using a bar coater to form a support resin layer 12 . Then, the acrylic heat conductive composition is coated on the support resin layer 12, and under specific conditions, ultraviolet rays are irradiated from both sides of the acrylic heat conductive composition surface and the support resin layer to form the heat conductive resin layer 11 on the support resin layer 12 . Thereby, a thermally conductive sheet composed of the supporting resin layer 12 and the thermally conductive resin layer 11 can be manufactured.

As described above, it contains at least one kind selected from adipic acid ester, pimelic acid ester, caprylic acid ester, azelaic acid ester and sebacic acid ester as a plasticizer of the thermally conductive resin layer 11 and contains a multifunctional thiol As a thiol compound, excellent flexibility can be obtained. Furthermore, the amount of outgassed when stored and heated at 150°C for 15 minutes can be 200 ppm or less. In addition, the thermally conductive sheet reduces outgassing without compromising thermal conductivity and flexibility, so it can be preferably used in precision devices such as hard disk devices and laser devices.

【Example】

<3. Example>

Hereinafter, embodiments of the present invention will be described. In this embodiment, a thermally conductive sheet having a layer composed of an acrylic thermally conductive composition is produced. Then, for each thermal conductive sheet, the thermal conductivity measurement, the compression ratio measurement, and the outgassing amount measurement are performed. Furthermore, the invention is not limited to these embodiments.

The production of the thermally conductive sheet, the measurement of the thermal conductivity, the measurement of the compression rate, and the measurement of the amount of outgas are performed in the following manner.

[Production of Thermal Conductivity Sheet]

Polyvinyl acetal resin (S-LEC BX-1, Sekisui Chemical Co., Ltd.) and styrene-isoprene block copolymer (HYBRAR 5125, Kuraray Co., Ltd.) were mixed in a ratio of 8:2 A support resin composition is obtained. Using a bar coater, the support resin composition was applied to the PET film to form a support resin layer with a thickness of 0.5 mm.

The acrylic heat conductive composition is coated on the support resin layer, and ultraviolet rays are simultaneously irradiated from both sides of the acrylic heat conductive composition surface and the support resin layer at an irradiation intensity of 1 mW/cm ² for 5 minutes to form a heat conductive resin on the support resin layer Layer to produce a thermally conductive sheet composed of a supporting resin layer with a thickness of 0.005 mm and a thermally conductive resin layer with a thickness of 1.0 mm.

[Measurement of thermal conductivity]

Using a bar coater, apply the acrylic thermally conductive composition to the PET film. Simultaneously irradiate the ultraviolet rays for 10 minutes from both sides of the acrylic thermally conductive composition surface and the supporting resin layer with an irradiation intensity of 1 mW/cm ² . A thermally conductive resin layer with a thickness of 1.0 mm is formed on the resin layer. The thermal conductivity in the thickness direction of the thermally conductive resin layer was measured using a thermal conductivity measuring device according to ASTM D5470 with a load of 1 kgf/cm ² .

[Measurement of compression ratio]

Using a bar coater, apply the acrylic thermally conductive composition to the PET film. Simultaneously irradiate the ultraviolet rays for 10 minutes from both sides of the acrylic thermally conductive composition surface and the supporting resin layer with an irradiation intensity of 1 mW/cm ² . A thermally conductive resin layer with a thickness of 1.0 mm is formed on the resin layer. The compressibility of the thermally conductive resin layer is calculated by measuring the initial thickness and the thickness when a load of 1 kgf/cm ² is applied.

[Determination of outgassing amount]

The outgassing amount was measured using the thermally conductive sheet produced in the above manner. The amount of outgassing of the thermally conductive sheet is measured by the purge & capture method. The thermally conductive sheet was sealed in an ampoule, heated with a purge & capture device at 150°C for 15 minutes to take out gas, and then introduced into a GC/MS device, and the amount of gas generated was calculated in tetradecane conversion.

[1. About plasticizer]

Diisodecyl sebacate (DIDS) and diisodecyl adipate (DIDA) were used as plasticizers to check the amount of outgassing.

<Example 1>

As shown in Table 1, 100 parts by mass of ISTA as a monofunctional acrylate, 100.00 parts by mass of DIDA as an adipate, 9.87 parts by mass of polypropylene glycol diacrylate, 4.21 parts by mass of polyfunctional thiol, and an antioxidant 2.11 Parts by mass, secondary antioxidant 2.11 parts by mass, acetylphosphine oxide photoinitiator 0.07 parts by mass, α-hydroxyketone photoinitiator 0.15 parts by mass, aluminum hydroxide with an average particle size (D50) of 60 to 80 μm 642.11 parts by mass and 642.11 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 1, the thermal conductivity of the thermally conductive resin layer of Example 1 is 1.72 W/m. K, the compression ratio is 11.30%. In addition, the thermal conduction sheet is measured using a purge & capture device, The results are: 1.95 μg/g of ketone and alcohol-based gas such as acetone and isopropanol; 0.689 μg/g of aromatic-based gas such as toluene, ethylbenzene, and xylene; 4.738 μg of gas from decomposition products of photoinitiator /g; gas with carbon number 18 alcohol 23.1 μg/g; gas with ISTA 13.3 μg/g; and other gases 47.4 μg/g, and the total outgassing amount is 90.4 μg/g.

<Example 2>

As shown in Table 1, 100 parts by mass of ISTA as monofunctional acrylate, 123.53 parts by mass of DIDS as sebacate, 12.59 parts by mass of polypropylene glycol diacrylate, 4.55 parts by mass of polyfunctional thiol, and 2.38 parts of antioxidant Mass parts, secondary antioxidant 2.37 parts by mass, acetylphosphine oxide photoinitiator 0.09 parts by mass, α-hydroxyketone photoinitiator 0.17 parts by mass, aluminum hydroxide with an average particle size (D50) of 60 to 80 μm 717.65 parts by mass and 717.65 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 1, the thermal conductivity of the thermally conductive resin layer of Example 2 is 1.65W/m. K, the compression rate is 10.50%. In addition, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol and alcohol-based gases were generated 2.427 μg/g; aromatic gases such as toluene, ethylbenzene and xylene were 2.921 μg/g; photoinitiator decomposition gas 6.367μg/g; carbon number 18 alcohol gas 20.7μg/g; ISTA gas 10.9μg/g; and other gas 54.4μg/g, and the total outgassing amount is 97.7μg/g.

<Example 3>

As shown in Table 1, 100 parts by mass of ISTA as a monofunctional acrylate, 65.13 parts by mass of DIDA as an adipate, 7.02 parts by mass of polypropylene glycol diacrylate, 3.55 parts by mass of polyfunctional thiol, and an antioxidant 1.76 Parts by mass, secondary antioxidants 1.73 parts by mass, oxyacetyl Phosphine-based photoinitiator 0.06 parts by mass, α-hydroxyketone-based photoinitiator 0.12 parts by mass, aluminum hydroxide 581.40 parts by mass with an average particle diameter (D50) of 60 to 80 μm, and hydrogen with an average particle size (D50) of 7.4 μm 581.40 parts by mass of alumina was added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 1, the thermal conductivity of the thermally conductive resin layer of Example 3 is 1.77 W/m. K, the compression rate is 14.48%. In addition, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol, alcohol-based gases were generated 3.151 μg/g; toluene, ethylbenzene, xylene and other aromatic gases 2.534 μg/g; photoinitiator decomposition gas 7.658 μg/g; carbon number 18 alcohol gas 31.8 μg/g; ISTA gas 13.4 μg/g; and other gases 41.2 μg/g, and the total outgassing is 99.8μg/g.

<Example 4>

As shown in Table 1, 100 parts by mass of ISTA as monofunctional acrylate, 123.46 parts by mass of DIDS as sebacate, 10.98 parts by mass of polypropylene glycol diacrylate, 4.37 parts by mass of polyfunctional mercaptan, and 2.37 parts of antioxidant Parts by mass, secondary antioxidant 2.34 parts by mass, acetylphosphine oxide photoinitiator 0.08 parts by mass, α-hydroxyketone photoinitiator 0.16 parts by mass, aluminum hydroxide with an average particle size (D50) of 60 to 80 μm 716.61 parts by mass and 716.61 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 1, the thermal conductivity of the thermally conductive resin layer of Example 4 is 1.65W/m. K, the compression rate is 27.07%. In addition, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol and alcohol-based gases were generated 1.972 μg/g; aromatic gases such as toluene, ethylbenzene and xylene were 2.519 μg/g; gas of photoinitiator decomposition product 8.097 μg/g; The gas with an alcohol of carbon number 18.1 μg/g; the gas of ISTA 11.4 μg/g; and other gases 52.9 μg/g, and the total outgassing amount is 95.0 μg/g.

<Example 5>

As shown in Table 1, 100 parts by mass of ISTA as monofunctional acrylate, 63.32 parts by mass of DIDS as sebacate, 37.02 parts by mass of DIDA as adipate, 9.84 parts by mass of polypropylene glycol diacrylate, 4.19 parts by mass of polyfunctional thiol, 2.10 parts by mass of antioxidant, 2.12 parts by mass of secondary antioxidant, 0.07 parts by mass of oxyphosphine oxide photoinitiator, 0.15 parts by mass of α-hydroxyketone photoinitiator, average particle size 641.98 parts by mass of aluminum hydroxide with a diameter (D50) of 60 to 80 μm and 641.98 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 1, the thermal conductivity of the thermally conductive resin layer of Example 5 is 1.67 W/m. K, the compression rate is 17.66%. In addition, the thermal conductive sheet was measured by a purge & capture device, and the result was that ketones such as acetone and isopropanol and alcohol-based gases were generated at 3.509 μg/g; and aromatic gases such as toluene, ethylbenzene and xylene were at 3.597 μg/g; photoinitiator decomposition gas 6.855μg/g; carbon number 18 alcohol gas 22.2μg/g; ISTA gas 29.3μg/g; and other gases 31.9μg/g, and the total outgassing amount is 97.4 μg/g.

<Example 6>

As shown in Table 1, 100 parts by mass of ISTA as monofunctional acrylate, 63.22 parts by mass of DIDS as sebacate, 36.88 parts by mass of DIDA as adipate, 9.83 parts by mass of polypropylene glycol diacrylate, 4.10 parts by mass of polyfunctional thiol, 2.11 parts by mass of antioxidant, 2.23 parts by mass of secondary antioxidant, 0.08 parts by mass of oxyphosphine oxide photoinitiator, α-hydroxyl Add 0.15 parts by mass of ketone-based photoinitiator, 642.11 parts by mass of aluminum hydroxide with an average particle size (D50) of 60 to 80 μm and 642.11 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm, add to the mixer and mix, Acrylic thermal conductive composition was obtained. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 1, the thermal conductivity of the thermally conductive resin layer of Example 6 is 1.80W/m. K, the compression ratio is 18.98%. In addition, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol and alcohol-based gases were generated 3.106 μg/g; toluene, ethylbenzene, xylene and other aromatic gases 3.320 μg/g; gas of decomposition product of photoinitiator 7.148μg/g; gas of alcohol with carbon number 18 22.4μg/g; gas of ISTA 10.9μg/g; and other gas 34.2μg/g, and the total outgassing amount is 81.0μg/g.

ISTA: isostearyl acrylate

DIDS: diisodecyl sebacate

DIDA: diisodecyl adipate

Polypropylene glycol diacrylate: M-270, East Asia Synthetic Co., Ltd.

Multifunctional thiol: Neopentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT PE1, Showa Denko (share))

Antioxidant: 3-(3,5-di-tert-butyl-4-hydroxyphenyl) stearyl propionate (AO- 50, Edico (shares))

Secondary antioxidant: 1,1-bis(2-hydroxy-3,5-di-third-pentylphenyl) methane acrylate monoester (Sumilizer GP, Sumitomo Chemical Co., Ltd.)

Acetylphosphine oxide photoinitiator: bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (Irgacure 819, BASF Japan (stock))

Alpha-hydroxyketone photoinitiator: oligo[2-hydroxy-2-methyl-1-{4-(1-methylvinyl)phenyl)acetone (esacure one, Lamberti (share))

By using diisodecyl sebacate (DIDS) and diisodecyl adipate (DIDA) as plasticizers as shown in Examples 1 to 6, 1.0 W/m can be achieved. Thermal conductivity above K, compression rate above 10% and air release below 100ppm. Therefore, it can be seen that excellent flexibility can be obtained by using at least one selected from adipic acid ester, pimelic acid ester, suppository acid ester, azelaic acid ester, and sebacic acid ester as a plasticizer, and a low Release gas.

Then, lauryl acrylate (LA) was used as the monofunctional acrylate, and diisodecyl sebacate (DIDS) was used as the plasticizer to check the amount of outgassing.

<Example 7>

As shown in Table 2, 100 parts by mass of LA as a monofunctional acrylate, 214.0 parts by mass of DIDS as a sebacate ester, 18.0 parts by mass of polypropylene glycol diacrylate, 6.0 parts by mass of polyfunctional thiol, and an antioxidant 2.0 Mass parts, 2.0 parts by mass of secondary antioxidants, 1.0 parts by mass of oxyphosphine oxide photoinitiators, 2.0 parts by mass of α-hydroxyketone photoinitiators, aluminum hydroxide with an average particle diameter (D50) of 60 to 80 μm 935.0 parts by mass, 469.0 parts by mass of aluminum hydroxide surface-treated with a titanate coupling agent and an average particle size (D50) of 7.4 μm, and 468.0 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm were added to the agitator and Kneading was performed to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 2, the thermal conductivity of the thermally conductive resin layer of Example 7 is 1.80W/m. K, the compression ratio is 14.60%. In addition, the thermal conductive sheet was measured by a purge & capture device, and the results were: 1.95 μg/g of ketones such as acetone, isopropanol, and alcohol-based gas; and 0.689 aromatic gases such as toluene, ethylbenzene, and xylene. μg/g; photoinitiator decomposition product gas 4.738μg/g; dodecanol gas 30.9μg/g; and LA gas 4.1μg/g, and the total outgassing amount is 68.2μg/g.

<Example 8>

As shown in Table 2, 100 parts by mass of LA as monofunctional acrylate, 47.0 parts by mass of DIDS as sebacate, 4.0 parts by mass of polypropylene glycol diacrylate, 2.0 parts by mass of polyfunctional thiol, and 0.8 parts of antioxidant Mass parts, 0.8 parts by mass of secondary antioxidants, 0.3 parts by mass of oxyphosphine oxide photoinitiators, 0.7 parts by mass of α-hydroxyketone photoinitiators, aluminum hydroxide with an average particle diameter (D50) of 60 to 80 μm 414.3 parts by mass, 205.7 parts by mass of aluminum hydroxide surface-treated with a titanate coupling agent and an average particle size (D50) of 7.4 μm, and 205.9 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm were added to the mixer and Kneading was performed to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 2, the thermal conductivity of the thermally conductive resin layer of Example 8 is 1.77 W/m. K, the compression rate is 11.23%. In addition, the thermal conductive sheet was measured by a purge & capture device, and the result was that ketones such as acetone and isopropanol and alcohol-based gases were generated 6.296 g/g; aromatic gases such as toluene, ethylbenzene and xylene were 3.720 μg/g; photoinitiator decomposition gas 22.661 μg/g; dodecanol gas 67.7 μg/g; and LA gas 13.4 μg/g, and the total outgassing amount is 113.8 μg/g.

LA: Lauryl acrylate

DIDS: diisodecyl sebacate

Polypropylene glycol diacrylate (M-270, East Asia Synthetic Co., Ltd.)

Multifunctional thiol: Neopentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT PE1, Showa Denko (share))

Antioxidant: 3-(3,5-tris-tert-butyl-4-hydroxyphenyl) stearyl propionate (AO-50, Aidike (share))

Secondary antioxidant: 1,1-bis(2-hydroxy-3,5-di-third-pentylphenyl) methane acrylate monoester (Sumilizer GP, Sumitomo Chemical Co., Ltd.)

Acetylphosphine oxide photoinitiator: bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (Irgacure 819, BASF Japan (share))

Alpha-hydroxyketone photoinitiator: oligomeric [2-hydroxy-2-methyl-1-{4-(1-methylvinyl)phenyl}acetone (esacure one, Lamberti (share))

That is, in the case of using lauryl acrylate (LA) as a monofunctional (meth)acrylate instead of isostearyl acrylate (ISTA) as in Examples 7 and 8, a low outgassing amount can also be achieved.

Subsequently, lauryl acrylate (LA) was used as the monofunctional acrylate, and acetylated monoglyceride, polyetherester-based resin, and polycarbodiimide were used as plasticizers for inspection.

<Comparative Example 1>

As shown in Table 3, 100 parts by mass of LA as a monofunctional acrylate, 100.0 parts by mass of acetylated monoglyceride as a plasticizer, 9.7 parts by mass of polypropylene glycol diacrylate, and 4.1 parts by mass of polyfunctional thiol , 2.1 parts by mass of antioxidants, 2.1 parts by mass of secondary antioxidants, 0.1 parts by mass of oxyphosphine oxide photoinitiator, 0.2 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 60~80μm 640.1 parts by mass of aluminum hydroxide and 640.1 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 3, the thermally conductive sheet of Comparative Example 1 cannot be made into sheets, and the thermal conductivity and compression rate cannot be measured. Furthermore, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol and alcohol-based gases were generated 6.928g/g; aromatic gases such as toluene, ethylbenzene and xylene were 3.612 μg/g; photoinitiator decomposition gas 1.484 μg/g; dodecanol gas 26.8 μg/g; dibutylhydroxytoluene (BHT) gas 1.4 μg/g; LA gas 146.6 μg/g; And other gases 395.2μg/g, and the total outgassing amount is 582.0μg/g.

<Comparative Example 2>

As shown in Table 3, 100 parts by mass of LA as a monofunctional acrylate, 72.2 parts by mass of polyether ester as a plasticizer, 5.0 parts by mass of polycarbodiimide, and 11.2 parts by mass of polypropylene glycol diacrylate , 5.6 parts by mass of polyfunctional mercaptan, 1.9 parts by mass of antioxidant, 1.9 parts by mass of secondary antioxidant, 0.1 parts by mass of oxyphosphine oxide photoinitiator, 0.1 parts by mass of α-hydroxyketone photoinitiator, average 585.5 parts by mass of aluminum hydroxide with a particle size (D50) of 60 to 80 μm and 585.5 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm were added to the mixer and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 3, the thermal conductivity of the thermally conductive resin layer of Comparative Example 2 is 2.05W/m. K, the compression rate is 20.24%. In addition, the thermal conductive sheet was measured by a purge & capture device, and the result was that ketones such as acetone and isopropanol and alcohol-based gases generated 1.251 g/g; aromatic gases such as toluene, ethylbenzene, and xylene 1.193 μg/g; photoinitiator decomposition gas 8.647 μg/g; dodecanol gas 31.5 μg/g; dibutylhydroxytoluene (BHT) gas 2.2 μg/g; LA gas 118.8 μg/g; And other gases 97.7μg/g, and the total outgassing amount is 261.4μg/g.

LA: Lauryl acrylate

Acetylated monoglyceride (RIKEMAL PL-012, Riken Vitamin (share))

Polyetherester resin (W262, Di Aisheng (share))

Polycarbodiimide (Elastostab H01, Elastogran (share))

Polypropylene glycol di(meth)acrylate (M-270, East Asia Synthetic Co., Ltd.)

Multifunctional thiol: Neopentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT PE1, Showa Denko (share))

Antioxidant: 3-(3,5-di-tert-butyl-4-hydroxyphenyl) stearyl propionate (AO- 50, Edico (shares))

Secondary antioxidant: 1,1-bis(2-hydroxy-3,5-di-third-pentylphenyl) methane acrylate monoester (Sumilizer GP, Sumitomo Chemical Co., Ltd.)

Acetylphosphine oxide photoinitiator: bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (Irgacure 819, BASF Japan (stock))

Alpha-hydroxyketone photoinitiator: oligomeric [2-hydroxy-2-methyl-1-{4-(1-methylvinyl)phenyl}acetone (esacure one, Lamberti (share))

In Comparative Examples 1 and 2, acetylated monoglyceride, polyetherester-based resin, and polycarbodiimide were used as plasticizers, so the outgassing amount was 200 ppm or more.

[2. About monofunctional (meth)acrylate and polyfunctional (meth)acrylate]

Use lauryl acrylate (LA), isostearyl acrylate (ISTA) as monofunctional acrylate, use diisodecyl sebacate (DIDS), diisodecyl adipate (DIDA) as plasticizer, use 2-(2-vinyloxyethoxy) ethyl acrylate (VEEA) and polypropylene glycol diacrylate were used as polyfunctional (meth) acrylates to check the amount of outgassing.

<Example 9>

As shown in Table 4, 100 parts by mass of LA as a monofunctional acrylate, 77.2 parts by mass of DIDS as a sebacate ester, 5.81 parts by mass of a heterogeneous polymerizable monomer, 5.59 parts by mass of a polyfunctional thiol, and an antioxidant of 1.88 Mass parts, 1.81 parts by mass of secondary antioxidants, 0.06 parts by mass of oxyphosphine oxide photoinitiators, 0.15 parts by mass of α-hydroxyketone photoinitiators, aluminum hydroxide with an average particle size (D50) of 60 to 80 μm 587.0 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm 587.0 parts by mass was added to a stirrer and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 9 is 1.943 W/m. K, the compression rate is 12.68%. Furthermore, the thermal conductive sheet was measured with a purge & capture device, and the results were: ketones such as acetone and isopropanol, alcohol-based gases 3.182 g/g; aromatic gases such as toluene, ethylbenzene, and xylene 1.014 μg/g; photoinitiator decomposition gas 6.752μg/g; dodecanol and other gas 30.9μg/g; dibutylhydroxytoluene (BHT) gas 0.6μg/g; LA gas 13.4μg/g ; And other gases 39.5μg/g, and the total outgassing amount is 95.3μg/g.

<Example 10>

As shown in Table 4, 100 parts by mass of ISTA as a monofunctional acrylate, 75.4 parts by mass of DIDS as a sebacate ester, 6.83 parts by mass of a heterogeneous polymerizable monomer, 5.76 parts by mass of a polyfunctional thiol, and an antioxidant of 1.92 Parts by mass, secondary antioxidant 1.92 parts by mass, acetylphosphine oxide photoinitiator 0.06 parts by mass, α-hydroxyketone photoinitiator 0.17 parts by mass, aluminum hydroxide with an average particle size (D50) of 60 to 80 μm 586.5 parts by mass of aluminum hydroxide and 586.5 parts by mass of aluminum hydroxide having an average particle diameter (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 10 is 1.796W/m. K, the compression rate is 27.09%. In addition, the thermal conductive sheet was measured with a purge & capture device, and the results were: ketones such as acetone and isopropanol, alcohol-based gases 7.158g/g; toluene, ethylbenzene, xylene, and other aromatic-based gases 2.561 μg/g; gas of decomposition product of photoinitiator 4.441μg/g; gas of dibutylhydroxytoluene (BHT) 0.5μg/g; and other gas 51.6μg/g, and total outgassing amount is 66.3μg/g.

<Example 11>

As shown in Table 4, 100 parts by mass of ISTA as a monofunctional acrylate is used as sebac 77.2 parts by mass of ester of DIDS, 11.35 parts by mass of polypropylene glycol diacrylate, 5.52 parts by mass of polyfunctional thiol, 1.92 parts by mass of antioxidant, 1.91 parts by mass of secondary antioxidant, 0.03 parts by mass of oxyphosphine oxide photoinitiator Parts, 0.07 parts by mass of α-hydroxyketone photoinitiator, 586.5 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 60 to 80 μm, and 586.5 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm Stirrer and knead to obtain acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 11 is 1.740W/m. K, compression rate is 23.76%. Furthermore, the thermal conductive sheet was measured by a purge & capture device, and the result was that ketones such as acetone and isopropanol, alcohol-based gases were generated 4.006g/g; toluene, ethylbenzene, xylene and other aromatic-based gases 4.522 μg/g; photoinitiator decomposition product gas 2.210 μg/g; dibutylhydroxytoluene (BHT) gas 2.1 μg/g; and other gases 83.2 μg/g, and the total outgassing amount is 96.0 μg/g.

<Example 12>

As shown in Table 4, 50.5 parts by mass of LA as monofunctional acrylate, 49.5 parts by mass of ISTA, 77.1 parts by mass of DIDS as sebacate, 6.46 parts by mass of heteropolymerizable monomer, and 5.72 parts by mass of polyfunctional thiol Parts, antioxidant 1.93 parts by mass, secondary antioxidant 1.93 parts by mass, acetylphosphine oxide photoinitiator 0.06 parts by mass, α-hydroxyketone photoinitiator 0.16 parts by mass, average particle size (D50) 60~ 587.8 parts by mass of aluminum hydroxide at 80 μm and 587.8 parts by mass of aluminum hydroxide at an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 12 is 1.943 W/m. K, the compression rate is 15.53%. In addition, the thermal conduction sheet is measured using a purge & capture device, The results are: acetone, isopropanol and other ketones, alcohol-based gas 8.479g/g; toluene, ethylbenzene, xylene and other aromatic-based gas 2.274μg/g; photoinitiator decomposition product gas 3.625μg /g; gas such as dodecanol 13.9μg/g; gas of dibutylhydroxytoluene (BHT) 0.6μg/g; gas of LA 4.0μg/g; and other gases 56.1μg/g, and the total outgassing amount is 88.9μg/g.

<Example 13>

As shown in Table 4, 100 parts by mass of ISTA as monofunctional acrylate, 99.9 parts by mass of DIDS as sebacate, 9.95 parts by mass of polypropylene glycol diacrylate, 4.14 parts by mass of polyfunctional thiol, and 2.16 parts of antioxidant Mass parts, secondary antioxidants 2.13 parts by mass, acetylphosphine oxide photoinitiator 0.15 parts by mass, α-hydroxyketone photoinitiator 0.34 parts by mass, aluminum hydroxide with an average particle size (D50) of 60 to 80 μm 640.9 parts by mass and 640.9 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm were added to the stirrer and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 13 is 1.747 W/m. K, compression rate is 23.29%. Furthermore, the thermal conductive sheet was measured with a purge & capture device, and the result was: 14.294 g/g of ketones such as acetone and isopropanol, and alcohol-based gas; 10.750 aromatic-gases such as toluene, ethylbenzene, and xylene. μg/g; dibutylhydroxytoluene (BHT) gas 11.7μg/g; LA gas 3.3μg/g; and other gases 30.1μg/g, and the total outgassing amount is 70.2μg/g.

<Example 14>

As shown in Table 4, 100 parts by mass of ISTA as a monofunctional acrylate, 100.3 parts by mass of DIDS as a sebacate ester, 6.85 parts by mass of a heterogeneous polymerizable monomer, 4.06 parts by mass of a polyfunctional thiol, and an antioxidant 2.10 Parts by mass, secondary antioxidant 2.10 parts by mass, acetylphosphine oxide photoinitiator 0.14 parts by mass, α-hydroxyketone photoinitiator 0.35 parts by mass, average particle size (D50) 641.4 parts by mass of aluminum hydroxide from 60 to 80 μm and 641.4 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm were added to the mixer and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 14 is 1.773 W/m. K, compression rate is 25.33%. Furthermore, the thermal conductive sheet was measured with a purge & capture device, and it was found that ketones such as acetone and isopropanol and alcohol-based gases produced 11.445g/g; toluene, ethylbenzene, xylene and other aromatic gases 6.776 μg/g; Dibutylhydroxytoluene (BHT) gas 12.1μg/g; LA gas 3.5μg/g; and other gases 30.4μg/g, and the total outgassing amount is 64.2μg/g.

<Example 15>

As shown in Table 4, 100 parts by mass of ISTA as monofunctional acrylate, 81.0 parts by mass of DIDA as sebacate, 8.15 parts by mass of polypropylene glycol diacrylate, 3.81 parts by mass of polyfunctional thiol, and 1.90 of antioxidant Mass parts, secondary antioxidant 1.90 parts by mass, acetylphosphine oxide photoinitiator 0.07 parts by mass, α-hydroxyketone photoinitiator 0.13 parts by mass, aluminum hydroxide with an average particle size (D50) of 60 to 80 μm 581.0 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm 581.0 parts by mass was added to a stirrer and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 15 is 1.675 W/m. K, compression rate is 23.38%. In addition, the thermal conductive sheet was measured by a purge & capture device, and the result was that ketones such as acetone and isopropanol and alcohol-based gases 2.827g/g were generated; and aromatic gases such as toluene, ethylbenzene and xylene were 2.936 μg/g; photoinitiator decomposition gas 7.528μg/g; dodecanol and other gas 22.8μg/g; ISTA gas 19.3μg/g; and other gases 32.3μg/g, and the total outgassing amount is 87.7 μg/g.

<Example 16>

As shown in Table 4, 100 parts by mass of ISTA as monofunctional acrylate, 123.5 parts by mass of DIDA as sebacate, 3.35 parts by mass of heteropolymerizable monomer, 5.88 parts by mass of polypropylene glycol diacrylate, and multifunctional 5.65 parts by mass of mercaptan, 2.35 parts by mass of antioxidant, 2.35 parts by mass of secondary antioxidant, 0.08 parts by mass of oxyphosphine oxide photoinitiator, 0.16 parts by mass of α-hydroxyketone photoinitiator, average particle size ( D50) 717.7 parts by mass of aluminum hydroxide from 60 to 80 μm and 717.7 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm are added to the mixer and kneaded to obtain an acrylic heat conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 16 is 1.525W/m. K, the compression ratio is 48.27%. In addition, the thermal conductive sheet was measured with a purge & capture device, and the results were: ketones such as acetone and isopropanol, alcohol-based gases 2.974 g/g; toluene, ethylbenzene, xylene and other aromatic-based gases 1.841 μg/g; gas of decomposition product of photoinitiator 7.275μg/g; gas of dodecanol etc. 16.7μg/g; gas of ISTA 7.1μg/g; and other gases 30.0μg/g, and total outgassing amount is 65.8 μg/g.

<Example 17>

As shown in Table 4, 100 parts by mass of ISTA as monofunctional acrylate, 81.0 parts by mass of DIDA as sebacate, 2.17 parts by mass of heterogeneous polymerizable monomer, 4.10 parts by mass of polypropylene glycol diacrylate, multifunctional Mercaptan 3.87 parts by mass, antioxidant 1.92 parts by mass, secondary antioxidant 1.90 parts by mass, acetylphosphine oxide photoinitiator 0.09 parts by mass, α-hydroxyketone photoinitiator 0.13 parts by mass, average particle size ( D50) 581.0 parts by mass of aluminum hydroxide from 60 to 80 μm and 581.0 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm are added to the agitator and kneaded to obtain an acrylic thermally conductive composition. Then, the thermally conductive sheet is obtained by the method described above.

As shown in Table 4, the thermal conductivity of the thermally conductive resin layer of Example 17 is 1.048W/m. K, the compression rate is 81.27%. Furthermore, the thermal conductive sheet was measured with a purge & capture device, and the result was that ketones such as acetone and isopropanol and alcohol-based gases were generated 4.248 g/g; toluene, ethylbenzene, xylene and other aromatic-based gases 1.790 μg/g; photoinitiator decomposition gas 4.753μg/g; dodecanol and other gas 22.4μg/g; ISTA gas 5.8μg/g; and other gases 37.4μg/g, and the total outgassing amount is 76.4 μg/g.

LA: Lauryl acrylate

ISTA: isostearyl acrylate

DIDS: diisodecyl sebacate

DIDA: diisodecyl adipate

Heterogeneous polymerizable monomer: 2-(2-vinyloxyethoxy) ethyl acrylate (VEEA)

Polypropylene glycol diacrylate: M-270, East Asia Synthetic Co., Ltd.

Multifunctional thiol: Neopentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT PE1, Showa Denko (share))

Antioxidant: 3-(3,5-tris-tert-butyl-4-hydroxyphenyl) stearyl propionate (AO-50, Aidike (share))

Secondary antioxidant: 1,1-bis(2-hydroxy-3,5-di-third-pentylphenyl) methane acrylate monoester (Sumilizer GP, Sumitomo Chemical Co., Ltd.)

Acetylphosphine oxide photoinitiator: bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (Irgacure 819, BASF Japan (stock))

Alpha-hydroxyketone photoinitiator: oligomeric [2-hydroxy-2-methyl-1-{4-(1-methylvinyl)phenyl}acetone (esacure one, Lamberti (share))

From the comparison between Example 9 and Example 10, it can be seen that outgassing can be reduced by using isostearyl acrylate having a carbon number greater than alkyl lauryl acrylate as a monofunctional (meth)acrylate.

Also, for example, according to the comparison between Example 10 and Example 11, it can be seen that the outgas can be reduced by using a monomer having a (meth)acryloyl group and a vinyl ether group in the same molecule as the multifunctional (meth)acrylate .

[3. About the number of thiol compounds and the effect of the added amount]

Then, the functional number and addition amount of the thiol compound were changed to examine the flexibility and outgassing amount based on the compression ratio.

<Example 18>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 73 parts by mass of sebacate (DIDA) as a plasticizer, 7.4 parts by mass of polypropylene glycol diacrylate, and 3.42 parts by mass of 4-functional thiol Parts, 1.9 parts by mass of antioxidant, 1.9 parts by mass of secondary antioxidant, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.43 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 60~ 551 parts by mass of aluminum hydroxide at 80 μm and 551 parts by mass of aluminum hydroxide at an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, by the above method, a thermally conductive sheet is produced.

As shown in Table 5, the thermal conductivity of the thermally conductive resin layer of Example 18 is 2.0W/m. K, the compression ratio is 18.3%. In addition, the thermal conductive sheet was measured by a purge & capture device, and it was found that ketones such as acetone and isopropanol and alcohol-based gases generated 6.768 μg/g; aromatic gases such as toluene, ethylbenzene and xylene 2.358 μg/g; photoinitiator decomposition gas 22.512μg/g; dodecanol gas 77.4μg/g; BHT gas 1.7μg/g; LA gas 11.0μg/g; and other gases 38.5μg/g , And the total outgassing amount is 160.4μg/g.

<Example 19>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 73 parts by mass of sebacate (DIDA) as a plasticizer, 7.4 parts by mass of polypropylene glycol diacrylate, and 3.42 parts by mass of trifunctional thiol Parts, 1.8 parts by mass of antioxidant, 1.9 parts by mass of secondary antioxidant, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.44 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 553 parts by mass of aluminum hydroxide from 60 to 80 μm and 553 parts by mass of aluminum hydroxide with an average particle size (D50) of 7.4 μm are added to the agitator and kneaded to obtain an acrylic thermally conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 5, the thermal conductivity of the thermally conductive resin layer of Example 19 is 2.0W/m. K, the compression rate is 12.7%. In addition, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol and alcohol-based gases were generated 5.91 μg/g; aromatic gases such as toluene, ethylbenzene and xylene were 2.097 μg/g; photoinitiator decomposition gas 19.375μg/g; dodecanol gas 75.5μg/g; BHT gas 1.8μg/g; LA gas 17.9μg/g; and other gas 40.0μg/g , And the total outgassing amount is 162.7μg/g.

<Example 20>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 76 parts by mass of sebacate (DIDA) as a plasticizer, 12.2 parts by mass of polypropylene glycol diacrylate, and 3.8 parts by mass of difunctional thiol Parts, 1.9 parts by mass of antioxidants, 1.9 parts by mass of secondary antioxidants, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.44 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 60~ 577 parts by mass of aluminum hydroxide at 80 μm and 577 parts by mass of aluminum hydroxide at an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 5, the thermal conductivity of the thermally conductive resin layer of Example 20 is 1.8 W/m. K, the compression ratio is 14.2%. In addition, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol and alcohol-based gases were generated at 3.216 μg/g; aromatic gases such as toluene, ethylbenzene and xylene were 3.623 μg/g; photoinitiator decomposition gas 24.969 μg/g; dodecanol gas 62.0 μg/g; BHT gas 2.0 μg/g; LA gas 17.2 μg/g; and Other gas is 40.7 μg/g, and the total outgassing amount is 153.7 μg/g.

<Comparative Example 3>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 73 parts by mass of sebacate (DIDA) as a plasticizer, 7.5 parts by mass of polypropylene glycol diacrylate, and 1.8 parts by mass of antioxidant, 1.8 parts by mass of secondary antioxidant, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.41 parts by mass of α-hydroxyketone photoinitiator, and 543 parts by mass of aluminum hydroxide with an average particle size (D50) of 60 to 80 μm And 543 parts by mass of aluminum hydroxide having an average particle diameter (D50) of 7.4 μm was added to the stirrer and kneaded to obtain an acrylic heat-conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 5, the thermal conductivity of the thermally conductive resin layer of Comparative Example 3 is 1.6 W/m. K, the compression rate is 1.6%. In addition, the thermal conductive sheet was measured with a purge & capture device. As a result, ketones such as acetone and isopropanol and alcohol-based gases were generated 5.995 μg/g; aromatic gases such as toluene, ethylbenzene and xylene were 2.362 μg/g; photoinitiator decomposition gas 10.425μg/g; dodecanol gas 87.1μg/g; BHT gas 1.4μg/g; LA gas 10.7μg/g; and other gas 42.9μg/g And the total outgassing amount is 161.0 μg/g.

<Comparative Example 4>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 72 parts by mass of sebacate (DIDA) as a plasticizer, 7.4 parts by mass of polypropylene glycol diacrylate, and 3.45 parts by mass of difunctional thiol Parts, 1.8 parts by mass of antioxidants, 1.8 parts by mass of secondary antioxidants, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.43 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 60~ 551 parts by mass of aluminum hydroxide at 80 μm and 551 parts by mass of aluminum hydroxide at an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 5, the thermally conductive resin of Comparative Example 4 could not be sliced. The thermal conductivity resin was measured with a purge & capture device. The results were: acetone, isopropanol and other ketones, alcohol-based gas 8.383 μg/g; toluene, ethylbenzene, xylene and other aromatic-based gas 0.819 μg/g; photoinitiator decomposition gas 5.029 μg/g; dodecanol gas 7.3 μg/g; BHT gas 0.6 μg/g; LA gas 2.4 μg/g; and other gases 4.1 μg/g And the total outgassing amount is 28.9μg/g.

<Comparative Example 5>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 73 parts by mass of sebacate (DIDA) as a plasticizer, 7.6 parts by mass of polypropylene glycol diacrylate, and 3.40 parts by mass of a monofunctional thiol Parts, 1.8 parts by mass of antioxidant, 1.8 parts by mass of secondary antioxidant, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.42 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 60~ 553 parts by mass of aluminum hydroxide at 80 μm and 553 parts by mass of aluminum hydroxide at an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 5, the thermally conductive resin of Comparative Example 5 could not be sliced. The thermal conductivity resin was measured by a purge & capture device, and the results were: ketones such as acetone and isopropanol, alcohol-based gases 5.510 μg/g; toluene, ethylbenzene, xylene and other aromatic-based gases 0.718 μg/g; photoinitiator decomposition gas 3.737 μg/g; dodecanol gas 13.8 μg/g; BHT gas 1.2 μg/g; LA gas 4.6 μg/g; and other gases 10.7 μg/g , And the total outgassing amount is 40.4μg/g.

<Comparative Example 6>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 73 parts by mass of sebacate (DIDA) as a plasticizer, 7.6 parts by mass of polypropylene glycol diacrylate, and 1.85 parts by mass of 4-functional thiol Parts, 1.9 parts by mass of antioxidants, 1.8 parts by mass of secondary antioxidants, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.44 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 60~ 553 parts by mass of aluminum hydroxide at 80 μm and 553 parts by mass of aluminum hydroxide at an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 5, the thermal conductivity of the thermally conductive resin layer of Comparative Example 6 is 2.0W/m. K, the compression ratio is 4.19%. In addition, the thermal conductive sheet was measured with a purge & capture device, and the result was that ketones such as acetone and isopropanol, alcohol-based gases were generated 0.636 μg/g; toluene, ethylbenzene, xylene and other aromatic-based gases 0.504 μg/g; photoinitiator decomposition gas 21.157μg/g; dodecanol gas 90.8μg/g; BHT gas 1.1μg/g; LA gas 12.5μg/g; and other gas 44.4μg/g And the total outgassing amount is 171.1 μg/g.

<Comparative Example 7>

As shown in Table 5, 100 parts by mass of LA as a monofunctional acrylate, 75 parts by mass of sebacate (DIDA) as a plasticizer, 7.5 parts by mass of polypropylene glycol diacrylate, and 5.06 parts by mass of 4-functional thiol Parts, 1.8 parts by mass of antioxidants, 1.8 parts by mass of secondary antioxidants, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.43 parts by mass of α-hydroxyketone photoinitiator, average particle size (D50) 60~ 552 parts by mass of aluminum hydroxide at 80 μm and 552 parts by mass of aluminum hydroxide at an average particle size (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 5, the thermally conductive resin of Comparative Example 7 could not be sliced. For this guide The thermal resin was measured by a purge & capture device. The results were: acetone, isopropanol and other ketones, alcohol-based gas 2.358μg/g; toluene, ethylbenzene, xylene and other aromatic-based gas 0.527μg/ g; gas of photoinitiator decomposition product 11.377 μg/g; gas of dodecanol 12.4 μg/g; gas of BHT 0.8 μg/g; gas of LA 4.6 μg/g; and other gases 8.2 μg/g, and The total outgassing amount is 40.2 μg/g.

LA: Lauryl acrylate

DIDS: diisodecyl sebacate

Polypropylene glycol diacrylate: M-270, East Asia Synthetic Co., Ltd.

4-functional thiol: neopentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT PE1, Showa Denko (share))

-2,4,6(1H,3H,5H)-三酮(Karenz MT NR1，昭和電工(股)) 3-functional thiol: 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-tris

-2,4,6(1H,3H,5H)-trione (Karenz MT NR1, Showa Denko (share))

2-functional thiol: 1,4-bis(3-mercaptobutyryloxy)butane (Karenz MT BD1, Showa Denko (share))

1-functional thiol: (Karenz MT EHMP, Showa Denko (share))

Antioxidant: 3-(3,5-di-tert-butyl-4-hydroxyphenyl) stearyl propionate (AO-50, Aidike (share))

Secondary antioxidant: 1,1-bis(2-hydroxy-3,5-di-third-pentylphenyl) methane acrylate monoester (Sumilizer GP, Sumitomo Chemical Co., Ltd.)

Acetylphosphine oxide photoinitiator: bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (Irgacure 819, BASF Japan (stock))

Alpha-hydroxyketone photoinitiator: oligomeric [2-hydroxy-2-methyl-1-{4-(1-methylvinyl)phenyl}acetone (esacure one, Lamberti (share))

In the case where no thiol compound was added as in Comparative Example 3, a thermally conductive sheet with low compression rate and flexibility could not be obtained. In addition, in the case where the amount of polypropylene glycol diacrylate added was almost the same as in Examples 18 and 19 as in Comparative Example 4, the tableting was impossible. The reason is believed to be that the unfunctionalized bifunctional thiol remains. In addition, as in Comparative Example 5, a monofunctional thiol is added In case of situation, it cannot be sliced. The reason is believed to be that the monofunctional thiol remains without being cross-linked. In addition, when the addition amount of the thiol compound is too small as in Comparative Example 6, a low compression rate and flexibility cannot be obtained. In addition, in the case where the amount of the thiol compound added is too large as in Comparative Example 7, the tablet cannot be formed. The reason is believed to be that the uncrosslinked thiol compound remains.

On the other hand, when a polyfunctional thiol is added as a thiol compound as in Examples 18 to 20, a compression ratio of 10% or more can be obtained and excellent flexibility can be obtained. In addition, when the amount of polypropylene glycol diacrylate added is greater than that in Examples 18 and 19 as in Example 20, even if it is a bifunctional thiol, excellent flexibility can be obtained.

[4. About the influence of monofunctional acrylate and polyfunctional (meth)acrylate]

Then, the monofunctional acrylate and the multifunctional (meth)acrylate were changed, and the flexibility and the amount of outgas based on the compression ratio were examined.

<Example 21>

As shown in Table 6, 100 parts by mass of ISTA as a monofunctional acrylate, 73.8 parts by mass of DIDS as a plasticizer, and 7.4 parts by mass of polypropylene glycol diacrylate as a multifunctional (meth)acrylate, multifunctional 3.5 parts by mass of mercaptan, 1.8 parts by mass of antioxidant, 2.0 parts by mass of secondary antioxidant, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.43 parts by mass of α-hydroxyketone photoinitiator, average particle size ( D50) 543 parts by mass of aluminum hydroxide from 60 to 80 μm and 543 parts by mass of aluminum hydroxide with an average particle diameter (D50) of 7.4 μm are added to the agitator and kneaded to obtain an acrylic thermally conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 6, the thermal conductivity of the thermally conductive resin layer of Example 21 is 1.659W/m. K, the compression ratio is 33.89%. In addition, the thermal conduction sheet was measured by a purge & capture device, and the result was that the total outgassing amount was 113.7 μg/g.

<Example 22>

As shown in Table 6, 100 parts by mass of LA as a monofunctional acrylate, 72.5 parts by mass of DIDS as a plasticizer, and 4.6 parts by mass of polyethylene glycol diacrylate as a multifunctional (meth)acrylate, 3.7 parts by mass of polyfunctional thiol, 1.8 parts by mass of antioxidant, 1.8 parts by mass of secondary antioxidant, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.40 parts by mass of α-hydroxyketone photoinitiator, average particle size 550 parts by mass of aluminum hydroxide having a diameter (D50) of 60 to 80 μm and 550 parts by mass of aluminum hydroxide having an average particle size of (D50) 7.4 μm were added to the agitator and kneaded to obtain an acrylic thermal conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 6, the thermal conductivity of the thermally conductive resin layer of Example 22 is 2.019W/m. K, the compression rate is 10.44%. In addition, the thermal conductive sheet was measured by a purge & capture device, and the result was that the total outgassing amount was 162.7 μg/g.

<Comparative Example 8>

As shown in Table 6, 100 parts by mass of LA as a monofunctional acrylate, 70.8 parts by mass of DIDS as a plasticizer, and 7.5 parts by mass of polyethylene glycol diacrylate as a multifunctional (meth)acrylate, 3.4 parts by mass of polyfunctional thiol, 1.8 parts by mass of antioxidant, 1.8 parts by mass of secondary antioxidant, 0.2 parts by mass of oxyphosphine oxide photoinitiator, 0.40 parts by mass of α-hydroxyketone photoinitiator, average particle size 539 parts by mass of aluminum hydroxide having a diameter (D50) of 60 to 80 μm and 539 parts by mass of aluminum hydroxide having an average particle diameter of (D50) of 7.4 μm were added to the agitator and kneaded to obtain an acrylic heat conductive composition. Then, a thermally conductive sheet is produced by the method described above.

As shown in Table 6, the thermal conductivity of the thermally conductive resin layer of Comparative Example 8 is 1.662W/m. K, the compression rate is 4.87%. In addition, the thermal conduction sheet was measured with a purge & capture device, and the result was that the total outgassing amount was 145.1 μg/g.

LA: Lauryl acrylate

ISTA: isostearyl acrylate

DIDS: diisodecyl sebacate

Polypropylene glycol diacrylate: M-270, East Asia Synthetic Co., Ltd.

Polyethylene glycol diacrylate: M-240, East Asia Synthetic Co., Ltd.

Multifunctional thiol: Neopentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT PE1, Showa Denko (share))

Antioxidant: 3-(3,5-di-tert-butyl-4-hydroxyphenyl) stearyl propionate (AO-50, Aidike (share))

Secondary antioxidant: 1,1-bis(2-hydroxy-3,5-di-third-pentylphenyl) methane acrylate monoester (Sumilizer GP, Sumitomo Chemical Co., Ltd.)

Acetylphosphine oxide photoinitiator: bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (Irgacure 819, BASF Japan (share))

Alpha-hydroxyketone photoinitiator: oligomeric [2-hydroxy-2-methyl-1-{4-(1-methylvinyl)phenyl}acetone (esacure one, Lamberti (share))

In the case of using isostearyl acrylate (ISTA) as the monofunctional (meth)acrylate as in Example 21, a compression ratio higher than that of Example 18 using lauryl acrylate (LA) can be obtained, which can be reduced Outgassing.

In the case of using polyethylene glycol diacrylate as the multifunctional (meth)acrylate as in Example 22, the compression ratio is lower than in Example 18 using polypropylene glycol diacrylate. In addition, in the case of adding polyethylene glycol diacrylate in an amount substantially equal to that of Example 18, as in Comparative Example 8, the compression rate further decreases. It can be considered that the reason is that the polyethylene glycol diacrylate has a lower linear carbon number than polypropylene glycol diacrylate.

Claims (23)

An acrylic thermally conductive composition comprising: monofunctional (meth)acrylate, polyfunctional (meth)acrylate, photopolymerization initiator, thermally conductive particles, plasticizer, and thiol compound, the plasticization The agent is at least one selected from the group consisting of diisodecyl adipate, diisodecyl pimelate, diisodecyl supramate, diisodecyl azelate, and diisodecyl sebacate. (Meth) acrylate contains monomers selected from polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, monomers having (meth)acryloyl and vinyl ether groups in one molecule At least one type of compressibility of the thermally conductive resin layer obtained by photocuring the acrylic thermally conductive composition from both sides at the irradiation intensity of 1 mW/cm ² at the same time for 10 minutes at a thickness of 1.0 mm and a load of 1 kgf/cm ² Under conditions, it is more than 10%. The acrylic thermal conductive composition according to item 1 of the patent application scope, wherein the content of the plasticizer is 30 parts by mass or more and 250 parts by mass or less with respect to 100 parts by mass of the monofunctional (meth)acrylate. For example, the acrylic thermal conductive composition of claim 1 or 2, wherein the monofunctional (meth)acrylate is a (meth)acrylic alkyl group having a linear or branched alkyl group having 8 to 22 carbon atoms ester. For example, the acrylic thermal conductive composition according to item 1 or 2 of the patent application, wherein the photopolymerization initiator is at least one of an oxyphosphine oxide photoinitiator or an α-hydroxyketone photoinitiator. For example, the acrylic thermal conductive composition according to item 3 of the patent application, wherein the photopolymerization initiator is at least one of an oxyphosphine oxide photoinitiator or an α-hydroxyketone photoinitiator. A thermally conductive sheet having a thermally conductive resin layer formed by photohardening an acrylic thermally conductive composition. The acrylic thermally conductive composition contains: monofunctional (meth)acrylate, multifunctional (meth)acrylate, thermal conductivity Particles, photopolymerization initiator, plasticizer, and thiol compound, the plasticizer is selected from diisodecyl adipate, diisodecyl pimelate, diisodecyl pivalate, azelaic acid di At least one of isodecyl ester and diisodecyl sebacate. The multifunctional (meth)acrylate contains at least one of polyethylene glycol di(meth)acrylate or polypropylene glycol di(meth)acrylate. One type, the compression ratio of the thermally conductive resin layer is 10% or more under the conditions of a thickness of 1.0 mm and a load of 1 kgf/cm ² . An acrylic thermally conductive composition, comprising: monofunctional (meth)acrylate, polyfunctional (meth)acrylate, photopolymerization initiator, thermally conductive particles, plasticizer and thiol compound, the plasticizer To select at least one of diisodecyl adipate, diisodecyl pimelate, diisodecyl supramate, diisodecyl azelate, and diisodecyl sebacate, the thiol compound It is a multifunctional thiol. The multifunctional (meth)acrylate contains polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, and (meth)acrylonitrile in one molecule. At least one monomer based on a vinyl group and a vinyl ether group, the acrylic thermally conductive composition is irradiated with ultraviolet light at 1 mW/cm ² from both sides and irradiated with ultraviolet light for 10 minutes for photohardening. 1.0mm, under a load of 1kgf / cm ² conditions of 10% or more. The acrylic thermally conductive composition according to item 7 of the patent application scope, wherein the content of the multifunctional (meth)acrylate is 3 parts by mass relative to 100 parts by mass of the monofunctional (meth)acrylate The content of the thiol compound is 3 parts by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the monofunctional (meth)acrylate. The acrylic thermal conductive composition according to item 7 or 8 of the patent application, wherein the thiol compound is at least any one of a 3-functional thiol or a 4-functional thiol. The acrylic thermally conductive composition according to claim 7 or 8, wherein the content of the plasticizer is 30 parts by mass or more and 250 parts by mass or less with respect to 100 parts by mass of the monofunctional (meth)acrylate. The acrylic thermal conductive composition as claimed in item 9 of the patent application, wherein the content of the plasticizer is 30 parts by mass or more and 250 parts by mass or less with respect to 100 parts by mass of the monofunctional (meth)acrylate. For example, the acrylic thermal conductive composition of claim 7 or 8, wherein the monofunctional (meth)acrylate is a (meth)acrylic alkyl group having a linear or branched alkyl group having 8 to 22 carbon atoms ester. For example, the acrylic thermally conductive composition according to item 9 of the patent application, wherein the monofunctional (meth)acrylate is an alkyl (meth)acrylate having a linear or branched alkyl group having 8 to 22 carbon atoms. For example, the acrylic thermal conductive composition of claim 10, wherein the monofunctional (meth)acrylate is a (meth)acrylic acid alkyl ester having a linear or branched alkyl group having 8 to 22 carbon atoms. For example, the acrylic thermal conductive composition according to item 7 or 8 of the patent application, wherein the photopolymerization initiator is at least one of oxyphosphine oxide photoinitiator or α-hydroxyketone photoinitiator. The acrylic thermally conductive composition as claimed in item 9 of the patent scope, in which the photopolymerization starts The agent is at least one of an oxyphosphine oxide photoinitiator or an α-hydroxyketone photoinitiator. For example, the acrylic thermal conductive composition according to item 10 of the patent application range, wherein the photopolymerization initiator is at least one of an oxyphosphine oxide photoinitiator or an α-hydroxyketone photoinitiator. For example, the acrylic thermal conductive composition according to item 12 of the patent application range, wherein the photopolymerization initiator is at least one of an oxyphosphine oxide photoinitiator or an α-hydroxyketone photoinitiator. A thermally conductive sheet having a thermally conductive resin layer made by photohardening an acrylic thermally conductive composition, the acrylic thermally conductive composition containing: monofunctional (meth)acrylate, multifunctional (meth)acrylate, photopolymerization Initiator, thermally conductive particles, plasticizer and thiol compound, the plasticizer is selected from diisodecyl adipate, diisodecyl pimelate, diisodecyl pivalate, and diisoazelaic acid At least one of decyl ester and diisodecyl sebacate, the thiol compound is a multifunctional thiol, and the multifunctional (meth)acrylate contains polyethylene glycol di(meth)acrylate or polypropylene glycol At least one type of di(meth)acrylate, the compression ratio of the thermally conductive resin layer is 10% or more under the conditions of a thickness of 1.0 mm and a load of 1 kgf/cm ² . An acrylic thermally conductive composition comprising: monofunctional (meth)acrylate, polyfunctional (meth)acrylate, photopolymerization initiator, thermally conductive particles, plasticizer, and thiol compound, the plasticization The agent is at least one selected from the group consisting of pimelic acid ester, caprylic acid ester, azelaic acid ester and sebacic acid ester. The polyfunctional (meth) acrylate contains polyethylene glycol di(meth) acrylic acid At least one kind of ester, polypropylene glycol di(meth)acrylate, monomer having a (meth)acryloyl group and vinyl ether group in one molecule, and the acrylic thermal conductive composition is 1 mW/cm ² from both sides The compressibility of the thermally conductive resin layer obtained by simultaneously irradiating ultraviolet rays for 10 minutes and photocuring is 10% or more under the conditions of a thickness of 1.0 mm and a load of 1 kgf/cm ² . A thermally conductive sheet having a thermally conductive resin layer formed by photohardening an acrylic thermally conductive composition. The acrylic thermally conductive composition contains: monofunctional (meth)acrylate, multifunctional (meth)acrylate, thermal conductivity Particles, photopolymerization initiator, plasticizer, and thiol compound, the plasticizer is at least one selected from the group consisting of pimelate, supramate, azelaate, and sebacate. The functional (meth)acrylate contains at least one of polyethylene glycol di(meth)acrylate or polypropylene glycol di(meth)acrylate. The thermal conductivity resin layer has a compression rate of 1.0 mm in thickness and a load of 1 kgf/cm Under the condition of ² , it is more than 10%. An acrylic thermally conductive composition, comprising: monofunctional (meth)acrylate, polyfunctional (meth)acrylate, photopolymerization initiator, thermally conductive particles, plasticizer and thiol compound, the plasticizer It is at least one selected from the group consisting of pimelic acid ester, supinate ester, azelaic acid ester, and sebacic acid ester. The thiol compound is a multifunctional thiol, and the multifunctional (meth)acrylate comprises At least one kind of ethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, monomer having (meth)acryloyl group and vinyl ether group in one molecule, the heat conduction composition of the acrylic system The compressibility of the thermally conductive resin layer obtained by irradiating ultraviolet light at the same time with an irradiation intensity of 1 mW/cm ² from both sides for 10 minutes at a thickness of 1.0 mm and a load of 1 kgf/cm ² is 10% or more. A thermally conductive sheet having a thermally conductive resin layer made by photohardening an acrylic thermally conductive composition, the acrylic thermally conductive composition containing: monofunctional (meth)acrylate, multifunctional (meth)acrylate, photopolymerization An initiator, a thermally conductive particle, a plasticizer, and a thiol compound, the plasticizer is at least one selected from the group consisting of pimelic acid ester, capric acid ester, azelaic acid ester, and sebacic acid ester. The compound is a multifunctional thiol, the multifunctional (meth)acrylate contains at least one of polyethylene glycol di(meth)acrylate or polypropylene glycol di(meth)acrylate, and the compression ratio of the thermally conductive resin layer Under the condition of 1.0mm thickness and 1kgf/cm ² load, it is more than 10%.

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