JP2011230050A - Screen for resin material-grinding machine, and method for grinding resin material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screen which is useful for efficiently grinding a resin material which still keeps its state soft even if it is cooled.SOLUTION: The screen 1 is installed outside a rotary blade 22 which a resin material-grinding machine 20 has. In addition, the screen has a cylindrical body part 1a and a plurality of aperture parts 1b which pass through the body part 1a from its internal face F1 to its external face F2. The aperture parts 1b have taper parts 1c which become gradually larger in aperture size from the internal face F1 of the body part 1a toward its external face F2.

Description

  The present invention relates to a screen installed on the outside of a rotary wing provided in a resin material pulverizer and a resin material pulverization method.

  In a manufacturing process of an electronic component device such as a semiconductor or an optical semiconductor package, a sealing material or a molding material is used. These materials occupy 70 to 97% by mass of an epoxy resin excellent in electrical characteristics, heat resistance, mass productivity and the like, additives such as a curing agent, a catalyst, a release agent, a flame retardant, and a colorant. It is composed of a filler. In response to the recent trend toward higher performance and smaller and thinner electronic and electrical equipment, smaller and thinner packages and surface mounting methods have become the mainstream, and improvements in reflow crack resistance of packages have been required. It was. Therefore, in order to improve the adhesion between the lead frame and the chip, reduce moisture absorption, and increase the strength, the epoxy resin has been reduced in molecular weight and the filler has been increased (Patent Document 1).

  The sealing epoxy resin molding material and the optical semiconductor package molding material are manufactured through the following steps. First, after mixing a predetermined amount of each component, the mixture is kneaded to obtain a kneaded product. The melted kneaded product is rolled into a sheet and cooled and solidified to obtain a cooled product. After this cooled product is pulverized using a pulverizer such as a power mill, for example, a cylindrical tablet is produced by compression molding.

JP 2005-97350 A

  By the way, due to the low molecular weight of the epoxy resin described above, the cooled product obtained by cooling and solidifying may maintain a soft state. A soft resin material has a problem that it is difficult to perform an appropriate pulverization process with a conventional pulverizer. In particular, when a pulverizer equipped with a rotating blade and a screen provided on the outside thereof for uniformizing the particle size of the pulverized material is used, the resin material adheres to the screen and the powder is discharged from the pulverizer. It becomes difficult to be done. When such a situation arises, it is necessary to clean the screen, and this work deteriorates the productivity of the resin material.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a screen useful for efficiently crushing a resin material that remains soft even when cooled. Moreover, this invention provides the method of grind | pulverizing a resin material using the grinder provided with this screen.

  The screen according to the present invention is installed on the outer side of a rotary wing provided in a resin material crusher, and includes a cylindrical main body and a plurality of openings penetrating from the inner surface to the outer surface of the main body. The opening portion has a tapered portion whose opening size increases from the inner surface to the outer surface of the main body portion.

  The screen of the present invention has a tapered portion. By providing the taper portion, the edge portion of the opening portion has an acute angle of more than 90 °. According to the screen of the present invention, compared with the conventional screen (see FIGS. 9 and 10) in which the angle of this portion is 90 °, the material adheres to the screen or aggregates even when the material is soft. Can be suppressed. Even if the size of the material that has collided with the inner surface of the screen is larger than the opening size, the material is crushed or cut by the tapered portion and easily passes through the opening. Thereby, it becomes difficult to produce the obstruction | occlusion of an opening part. In the conventional screen 8 shown in FIGS. 9 and 10, the opening 8b provided in the main body 8a is constant, and the angle of the edge portion 8c is 90 °.

  The opening may have a circular cross-sectional shape perpendicular to the direction from the inner surface to the outer surface of the main body, or may be a slit shape. When the opening is provided in a slit shape, the angle formed by the axial direction of the main body and the longitudinal direction of the slit-shaped opening can be any angle from 0 to 90 °. The slit-shaped opening is advantageous in that the cleaning operation is easy even when the material adheres to the screen and the time required for maintenance can be shortened.

  The resin material pulverization method according to the present invention includes a step of supplying a resin material to a resin pulverizer including a rotary blade and the screen installed outside the rotary blade, and a resin in a taper portion of the rotary blade and the screen. And crushing the material. Since this pulverization method uses the resin pulverizer equipped with the screen according to the present invention, the resin material is pulverized not only by the rotating blades but also by the tapered portion when it collides with the screen.

  According to the present invention, it is possible to efficiently pulverize a resin material that remains soft even when cooled.

It is a schematic cross section which shows an example of the resin grinder provided with the screen which concerns on this invention. 1 is a perspective view showing a first embodiment of a screen according to the present invention. It is sectional drawing which shows the opening part which the screen shown in FIG. 2 has. (A) is a figure which shows a mode that the resin material which collided with the screen based on this invention is grind | pulverized by a taper part, (b) is a figure which shows a mode that the resin material which collided with the conventional screen adheres to a screen. is there. It is a perspective view which shows 2nd embodiment of the screen which concerns on this invention. FIG. 6 is a cross-sectional view of the opening of the screen shown in FIG. 5, (a) is a view showing a cross section perpendicular to the axial direction of the screen, and (b) is a view showing a cross section parallel to the axial direction of the screen. It is a perspective view which shows 3rd embodiment of the screen which concerns on this invention. It is a perspective view which shows 4th embodiment of the screen which concerns on this invention. It is a perspective view which shows the conventional screen. It is a perspective view which shows the opening part which the screen shown in FIG. 9 has.

  A preferred embodiment of the present invention will be described with reference to the drawings.

<Resin crusher>
A resin material crusher 20 shown in FIG. 1 includes an apparatus main body 21 having a material inlet 21a and an outlet 21b, a rotary blade 22 for crushing resin, a shaft 23 on which a plurality of rotary blades are fixed, A motor 25 for rotating the shaft 23 and a cylindrical screen 1 provided so as to surround the outer side of the rotary blade 22 are provided. The lower end of the screen 1 is closed with a bottom plate 26. As shown in FIG. 1, the material from the inlet 21 a is pulverized mainly by the rotary blades 22 to reduce the particle size, passes through the screen 1, and is discharged from the outlet 21 b. Specific examples of the resin material grinder 20 include a power mill (Dalton Co., Ltd., trade name: P-5).

  The configuration of the screen 1 according to the first embodiment will be described with reference to FIGS. The screen 1 includes a cylindrical main body 1a and a plurality of openings 1b penetrating from the inner surface F1 to the outer surface F2 of the main body 1a. The opening 1b has a tapered portion 1c whose opening size increases from the inner surface F1 to the outer surface F2 of the main body 1a. The arrangement of the openings 1b is not particularly limited, but a large number of openings 1b can be provided in a close-packed arrangement. In addition, as a material of the screen 1, a metal, a metal alloy, a ceramic material, etc. are mentioned.

  Since the screen 1 is provided with the tapered portion 1c, the edge portion of the opening 1b has an acute angle of more than 90 ° on the inner surface F1 side. According to the screen 1, even if the material is soft, it is possible to suppress the material from adhering to and aggregating on the screen 1. That is, when the material M crushed by the rotary blades 22 collides with the inner surface F1 of the screen 1, it is further crushed or cut at the taper portion 1c, so that it is difficult to adhere to the part. Even if the size of the material M colliding with the inner surface F1 of the screen 1 is larger than the opening size of the opening 1b, the material M is crushed by the tapered portion 1c and easily passes through the opening 1b. Thereby, obstruction | occlusion of the opening part 1b becomes difficult to produce (refer Fig.4 (a)). On the other hand, in the conventional screen in which the inner diameter of the opening is constant and the angle of the edge portion is 90 °, the material easily adheres to the edge portion (see FIG. 4B). In FIG. 4, an arrow F indicates the direction in which the material flows.

  The opening 1b of the screen 1 has a circular cross-sectional shape perpendicular to the direction from the inner surface F1 to the outer surface F2 of the main body 1a. The inner diameter of the opening 1b on the inner surface F1 side may be appropriately set according to the characteristics of the material, but is preferably 10 to 1 mm and more preferably 5 to 3 mm.

  Note that the shape of the opening is not limited to a circle as long as the tapered portion is provided so that the edge of the opening has an acute angle on the inner surface F1 side. The angle of the taper portion (angle α) is preferably 80 to 10 °, and more preferably 60 to 30 °, from the viewpoint of sufficiently and stably achieving the effects of the present invention. The shape of the opening may be oval or rectangular, and may be slit as described below. The slit-shaped opening is advantageous in that the cleaning operation is easy even when the material adheres to the screen and the time required for maintenance can be shortened. When the opening has a slit shape, the opening width on the inner surface F1 side may be appropriately set according to the characteristics of the material, but it is more preferably 10 to 1 mm and 5 to 3 mm.

  The configuration of the screen 2 according to the second embodiment will be described with reference to FIGS. The screen 2 includes a cylindrical main body 2a and a plurality of slit-shaped openings 2b penetrating from the inner surface F1 to the outer surface F2 of the main body 2a. The opening 2b has a tapered portion 2c whose opening size increases from the inner surface F1 to the outer surface F2 of the main body 2a (see FIG. 6A). In the screen 2, the axial direction A of the main body 2a and the longitudinal direction B of the slit-shaped opening 2b coincide.

  The configuration of the screen 3 according to the third embodiment will be described with reference to FIG. The screen 3 includes a cylindrical main body 3a and a plurality of slit-shaped openings 3b penetrating from the inner surface F1 to the outer surface F2 of the main body 3a. The opening 3b has a tapered portion 3c whose opening size increases from the inner surface F1 to the outer surface F2 of the main body 3a. In the screen 3, the opening 3b is provided so that the axial direction A of the main body 3a and the longitudinal direction B of the slit-like opening 3b form an angle β. The angle β can be greater than 0 ° and 90 ° or less, and is preferably 80 to 10 °, and preferably 60 to 30 ° from the viewpoint of suppressing the resin adhesion to the screen 3 at a higher level. It is more preferable.

  The configuration of the screen 4 according to the fourth embodiment will be described with reference to FIG. The screen 4 includes a cylindrical main body 4a and a plurality of slit-shaped openings 4b penetrating from the inner surface F1 to the outer surface F2 of the main body 4a. The opening 4b has a tapered portion 4c whose opening size increases from the inner surface F1 to the outer surface F2 of the main body 4a. In the screen 4, a plurality of openings 4b are arranged in the circumferential direction of the main body 4a, and a set of the plurality of openings 4b in the circumferential direction is further arranged in the axial direction of the main body 4a. Is provided.

<Method of grinding resin material>
A method for pulverizing the resin material using the resin material pulverizer 20 will be described. The method for pulverizing a resin material according to the present embodiment includes a step of supplying the resin material to the resin material pulverizer 20 and a step of pulverizing the resin material at the rotary blade 22 and the taper portion 1c of the screen 1. Since this pulverization method uses the resin material pulverizer 20 provided with the screen 1, the resin material is pulverized not only by the rotary blades 22 but also by the tapered portion 1 c when it collides with the screen 1. The resin material crusher 20 may be equipped with a screen 2, 3 or 4 instead of the screen 1.

  The screens 1 to 4 are particularly useful for efficiently pulverizing a resin material that remains soft even when cooled. The resin material that maintains a soft state even when cooled refers to a material having a Shore A hardness of 10 to 100 at a temperature of 0 to 30 ° C. In the present embodiment, the materials to be crushed are an epoxy resin composition for sealing and a molding material composition for optical semiconductor packages. The components contained in these materials will be described.

(Epoxy resin composition for sealing)
As an epoxy resin, the epoxy resin generally used with the epoxy resin molding material for sealing is mentioned. For example, phenol novolac type epoxy resin, orthocresol novolak type epoxy resin, phenol resin including epoxy resin having triphenylmethane skeleton, phenols such as cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F and / or α -Epoxy novolak resin obtained by condensation or cocondensation of naphthols such as naphthol, β-naphthol, dihydroxynaphthane and the like and compounds having an aldehyde group such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, salicylaldehyde in the presence of an acidic catalyst. Novolac epoxy resin, bisphenol A, bisphenol F, bisphenol S, diglycidyl ether such as alkyl-substituted or unsubstituted bisphenol Reaction of polyamines such as ethers, stilbene type epoxy resins, hydroquinone type epoxy resins, polybasic acids such as phthalic acid and dimer acid and epichlorohydrin, polyamines such as diaminodiphenylmethane, isocyanuric acid and epichlorohydrin Glycidylamine type epoxy resin, dicyclopentadiene and phenol co-condensation resin epoxidized product, biphenyl type epoxy resin, epoxy resin having naphthalene ring, naphthol / aralkyl resin epoxidized product, trimethylolpropane type epoxy resin, Examples thereof include terpene-modified epoxy resins, linear aliphatic epoxy resins obtained by oxidizing olefinic bonds with peracids such as peracetic acid, aliphatic epoxy resins, and sulfur atom-containing epoxy resins. These may be used alone or in combination of two or more.

  Moreover, as a hardening | curing agent of the said epoxy resin, the hardening | curing agent generally used with the epoxy resin molding material for sealing is mentioned. For example, phenols such as phenol, cresol, reilsin, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, these phenols and / or naphthols such as α-naphthol, β-naphthol, dihydroxynaphthalene and formaldehyde, Novolak type phenolic resin obtained by condensation or cocondensation with a compound having an aldehyde group such as benzaldehyde and salicylaldehyde in the presence of an acidic catalyst, various polyhydric phenol compounds such as tris (hydroxyphenyl) methane and dihydroxybiphenyl, A phenolic resin having a novolak structure containing a biphenyl derivative and / or a naphthalene derivative, a phenol aralkyl resin such as a phenol compound represented by the following general formula (I), naphtho Cyclopentadiene type phenols such as cyclopentadiene type phenol novolac resins and naphthol novolak resins synthesized by copolymerization from aralkyl type phenol resins such as aralkyl resins and biphenyl aralkyl resins, phenols and / or naphthols and cyclopentadiene. Examples thereof include resins, terpene-modified phenol resins, acid anhydrides such as maleic anhydride, phthalic anhydride, and pyromellitic anhydride, and aromatic amines such as metaphenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone.

（式（Ｉ）中、Ｒは炭素数１〜４のアルキル基、ｎは０以上の整数を示す。）

(In formula (I), R represents an alkyl group having 1 to 4 carbon atoms, and n represents an integer of 0 or more.)

  In addition, these hardening | curing agents can be used individually or in combination of 2 or more types. The blending amount of the curing agent with respect to the epoxy resin is preferably set such that the ratio of the number of epoxy groups in the epoxy resin / the hydroxyl group in the curing agent is in the range of 0.7 to 1.3.

  The filler is not particularly limited, but is preferably an inorganic filler, such as fused silica powder, crystalline silica powder, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, aluminum nitride, boron nitride, beryllia, zirconia, etc. One or more kinds of powders, beads obtained by spheroidizing these, single crystal fibers such as potassium titanate, silicon carbide, silicon nitride, and alumina, glass fibers, and the like can be blended and used. Furthermore, examples of the inorganic filler having a flame retardant effect include aluminum hydroxide, magnesium hydroxide, zinc borate and the like, and these can be used alone or in combination. In addition, it is preferable that the compounding quantity of an inorganic filler is 70 to 97 weight% of the whole molding material from the point of hygroscopicity and the reduction of a linear expansion coefficient, More preferably, it is 80 to 95 weight%.

  Epoxy resin molding materials include 2-methylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecyl as necessary. Imidazole compounds such as imidazole, triethylamine, benzyldimethylamine, α-methylbenzyldimethylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo (5,5) 4,0) tertiary amine compounds such as undecene-7, organometallic compounds such as zirconium tetramethoxide, zirconium tetrapropoxide, tetrakis (acetylacetonato) zirconium, tri (acetylacetonato) aluminum and tri E cycloalkenyl phosphine, trimethylphosphine, triethylphosphine, it can be used tributylphosphine, tri (p- methylphenyl) phosphine, a curing accelerator such as an organic phosphine compound such as tri (nonylphenyl) phosphine.

  Epoxy resin molding materials include brominated bisphenol A type epoxy resin, brominated phenol novolak type epoxy resin, brominated epoxy resin, brominated polycarbonate resin, brominated polystyrene resin, brominated polyphenylene oxide resin, tetra Flame retardants such as bromobisphenol A and decabromodiphenyl ether can be used. Also, metal oxides such as magnesium oxide and calcium oxide, metal hydroxides such as aluminum hydroxide and magnesium hydroxide, and composite metal hydroxides that are composites of two or more metal oxides / hydroxides, Metal compounds such as zinc borate and zinc molybdate, nitrogen-containing compounds and phosphorus-containing compounds can also be used as flame retardants.

  In addition, epoxy resin molding materials include various silane compounds such as epoxy silane, amino silane, mercapto silane, alkyl silane, ureido silane, vinyl silane, titanium, etc., as necessary, in order to increase the adhesion between the resin component and the filler. Coupling agents such as aluminum compounds, aluminum chelates, and aluminum / zirconium compounds can be used.

  Furthermore, various additives, such as a mold release agent, a coloring agent, a silicone type stress relaxation agent, or an ion trap agent, can be used for an epoxy resin molding material as needed. Examples of mold release agents include carnauba wax, montanic acid, stearic acid, higher fatty acids, higher fatty acid metal salts, ester waxes such as montanic acid esters, and oxidized or non-oxidized polyolefin waxes such as polyethylene and polyethylene oxide. Can be mentioned.

  Examples of inorganic fine particles include silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, aluminum nitride, boric acid nitride, beryllia, zirconia, etc., which have high purity, are thermally and chemically stable. Therefore, it is preferable to use silica.

(Mold material composition for optical semiconductor package)
The mold material composition for optical semiconductor packages is a thermosetting resin composition containing (A) an epoxy resin and (B) a curing agent.
It is.

<(A) Epoxy resin>
(A) As an epoxy resin, what is generally used with the epoxy resin molding material for electronic component sealing can be used. Examples of epoxy resins include epoxidized phenol and aldehyde novolak resins such as phenol novolac type epoxy resin and orthocresol novolak type epoxy resin, diglycidyl such as bisphenol A, bisphenol F, bisphenol S and alkyl-substituted bisphenol. Glycidylamine type epoxy resin obtained by reaction of polyamine such as ether, diaminodiphenylmethane and isocyanuric acid with epichlorohydrin, linear aliphatic epoxy resin obtained by oxidizing olefin bond with peracid such as peracetic acid, and alicyclic An epoxy resin is mentioned. These can be used alone or in combination of two or more.

  Among these, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, diglycidyl isocyanurate, triglycidyl isocyanurate, and 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid or A dicarboxylic acid diglycidyl ester derived from 1,4-cyclohexanedicarboxylic acid is preferable because of relatively little coloring. For the same reason, diglycidyl esters of dicarboxylic acids such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, methyltetrahydrophthalic acid, nadic acid and methylnadic acid are also suitable. Examples thereof include glycidyl esters such as nuclear hydrogenated trimellitic acid and nuclear hydrogenated pyromellitic acid having an alicyclic structure in which an aromatic ring is hydrogenated. Polyorganosiloxane having an epoxy group produced by heating and hydrolyzing and condensing a silane compound in the presence of an organic solvent, an organic base and water is also included. Further, as the component (A), an epoxy resin represented by the following formula (7), which is a copolymer of a glycidyl (meth) acrylate monomer and a polymerizable monomer, can also be used.

In Formula (7), R ¹ represents a glycidyl group, R ² represents a hydrogen atom or a methyl group, R ³ represents a hydrogen atom or a saturated or unsaturated monovalent hydrocarbon group having 1 to 6 carbon atoms. , R ⁴ represents a monovalent saturated hydrocarbon group. a and b represent a positive integer.

  In order to suppress coloration of the cured product, the epoxy resin is a cycloaliphatic selected from cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, norbornene, dicyclopentadiene, adamantane, hydrogenated naphthalene, and hydrogenated biphenyl. An alicyclic epoxy resin having an aliphatic hydrocarbon group derived by removing a hydrogen atom from a hydrocarbon is also preferred. The cycloaliphatic hydrocarbon may be substituted with a halogen atom or a linear or branched hydrocarbon group.

  From the viewpoint of suppressing resin contamination, 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol can be used as an epoxy resin, A product name “EHPE3150” manufactured by Daicel Chemical Industries, Ltd. is available as a commercial product.

<(B) Curing agent>
As a hardening | curing agent, what contains the polyhydric carboxylic acid condensate which condensed the carboxyl group-containing compound between molecules is preferable. (B) Since the hardening | curing agent contains such a polyhydric carboxylic acid condensate, the tolerance with respect to the alkaline degreasing liquid of the hardened | cured material formed from the thermosetting resin composition improves.

(Polyvalent carboxylic acid condensate)

  The polyvalent carboxylic acid condensate preferably contains a component represented by the following general formula (1) as a main component.

In Formula (1), R _x represents a divalent organic group, and is preferably a divalent saturated hydrocarbon group having a saturated hydrocarbon ring. When R _x is a saturated hydrocarbon group having a saturated hydrocarbon ring, the polyvalent carboxylic acid condensate can form a transparent cured product of an epoxy resin. A plurality of R _x in the same molecule may be the same or different. The saturated hydrocarbon ring of R _x may be substituted with a halogen atom or a linear or branched hydrocarbon group. The hydrocarbon group that substitutes the saturated hydrocarbon ring is preferably a saturated hydrocarbon group. The saturated hydrocarbon ring may be a single ring or a condensed ring, a polycyclo ring, a spiro ring or a ring assembly composed of two or more rings. R _x preferably has 3 to 15 carbon atoms. N represents an integer of 0 or more, preferably 0 to 200, and more preferably 0 to 100.

R _x is a group derived by removing a carboxyl group from a polyvalent carboxylic acid as a monomer used to obtain the polymer of formula (1). The polyvalent carboxylic acid as a monomer preferably has a boiling point higher than the reaction temperature of polycondensation.

More specifically, R _x is a hydrogen atom from a cyclic aliphatic hydrocarbon selected from cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, norbornene, dicyclopentadiene, adamantane, hydrogenated naphthalene and hydrogenated biphenyl. It is preferably a divalent group derived by removing. When R _x is these groups, the effect of obtaining a cured product that is transparent and less colored by heat is more remarkably exhibited. These cyclic saturated hydrocarbons may be substituted with a halogen atom or a linear or branched hydrocarbon group (preferably a saturated hydrocarbon group).

In particular, R _x is preferably a group derived by removing a carboxyl group from 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid or derivatives thereof. That is, R _x is preferably a divalent group represented by the following general formula (10). In formula (10), m represents an integer of 0 to 4. R _z represents a halogen atom or a linear or branched hydrocarbon group having 1 to 4 carbon atoms. When m is 2 to 4, a plurality of R _z may be the same or different, and may be connected to each other to form a ring.

  The weight average molecular weight Mw of the polyvalent carboxylic acid condensate is preferably 200 to 20000, and more preferably 300 to 10,000. When the weight average molecular weight Mw is less than 200, the viscosity becomes too low and when used as a curing agent for a thermosetting resin composition, it tends to be difficult to suppress the occurrence of resin stains during transfer molding, more than 20000 If it is large, the compatibility with the epoxy resin or the like tends to decrease, and the fluidity during transfer molding of the thermosetting resin composition tends to decrease.

The weight average molecular weight Mw is obtained by measuring under the following conditions using a standard polystyrene calibration curve by gel permeation chromatography (GPC).
(GPC conditions)
Pump: L-6200 type (manufactured by Hitachi, Ltd., trade name)
Column: TSKgel-G5000HXL and TSKgel-G2000HXL (trade name, manufactured by Tosoh Corporation)
Detector: L-3300RI type (manufactured by Hitachi, Ltd., trade name)
Eluent: Tetrahydrofuran Measurement temperature: 30 ° C
Flow rate: 1.0 mL / min

  The viscosity of the polyvalent carboxylic acid condensate measured by an ICI cone plate viscometer is preferably 10 to 30000 mPa · s at 150 ° C., more preferably 10 to 10000 mPa · s. When the viscosity of the polyvalent carboxylic acid condensate is less than 10 mPa · s, for example, an epoxy resin composition containing the polyvalent carboxylic acid condensate tends to be less effective in suppressing the occurrence of resin stains during transfer molding. If it exceeds s, the fluidity of the thermosetting resin composition tends to decrease in the mold during transfer molding. The viscosity of the polyvalent carboxylic acid condensate can be measured, for example, by Research Equipment (London) LTD. It can be measured using a manufactured ICI cone plate viscometer.

  The softening point of the polyvalent carboxylic acid condensate is preferably 20 to 200 ° C. Thereby, when disperse | distributing an inorganic filler in a resin composition containing a polyhydric carboxylic acid condensate using a 2 roll mill etc., favorable dispersibility and workability | operativity are obtained. The excellent dispersibility of the inorganic filler is particularly important in a thermosetting resin composition for transfer molding.

  Moreover, from the viewpoint of kneadability when producing a thermosetting resin composition using a roll mill, the polycarboxylic acid polycondensation polymer preferably has a softening point of 30 to 100 ° C, preferably 30 to 80 ° C. It is more preferable. When the softening point is less than 20 ° C., the handling property, kneading property and dispersibility are lowered during the production of the thermosetting resin composition, and it is difficult to effectively suppress the occurrence of resin stains during transfer molding. When the softening point exceeds 200 ° C., the curing agent may remain undissolved in the resin composition when heated to 100 to 200 ° C. by transfer molding, and it tends to be difficult to obtain a uniform molded body.

  The softening point of the polyvalent carboxylic acid condensation polymer can be set to a desired range by selecting the structure of the main chain and adjusting the weight average molecular weight. Generally, when a long-chain divalent carboxylic acid is used as a monomer, the softening point can be lowered, and when a highly polar structure is introduced, the softening point can be raised. In general, the softening point can be lowered by increasing the weight average molecular weight.

  In the polyvalent carboxylic acid condensate, the ICI cone plate viscosity, weight average molecular weight and softening point of the product can be adjusted according to the purpose by the charged composition ratio of the polyvalent carboxylic acid and the monocarboxylic acid before the condensation reaction. As the ratio of polyvalent carboxylic acid increases, the ICI cone plate viscosity, weight average molecular weight, and softening point tend to increase. However, depending on the conditions of the condensation reaction, the above-mentioned tendency is not necessarily exhibited, and it is necessary to take into account the reaction temperature, the degree of pressure reduction, and the reaction time, which are the conditions for the dehydration condensation reaction.

  The polyvalent carboxylic acid condensate is, for example, a carboxyl group that each has in the reaction solution containing the polyvalent carboxylic acid represented by the following general formula (5) and the monocarboxylic acid represented by the following general formula (6). Can be obtained by a method comprising a step of dehydrating condensation between molecules.

Wherein (5), _{R x} has the same meaning as _{R x} in formula (1). In formula (6), R _y represents a monovalent hydrocarbon group which may be substituted with an acid anhydride group or a carboxylic ester group.

  The dehydrating condensation reaction liquid is, for example, a polyhydric carboxylic acid and a monocarboxylic acid, and a dehydrating agent selected from acetic anhydride or propionic anhydride, acetyl chloride, an aliphatic acid chloride, and an organic base (such as trimethylamine) that dissolve them. Containing. For example, after the reaction solution is refluxed in a nitrogen atmosphere for 5 to 60 minutes, the temperature of the reaction solution is increased to 180 ° C., and polycondensation is performed by distilling off the generated acetic acid and water in an open system under a nitrogen stream. To advance. When generation of volatile components is no longer observed, polycondensation proceeds in a molten state at a temperature of 180 ° C. for 3 hours, more preferably for 8 hours while reducing the pressure in the reaction vessel. The produced polyvalent carboxylic acid condensate may be purified by recrystallization or reprecipitation using an aprotic solvent such as acetic anhydride.

  The polycarboxylic acid condensate obtained by such a method is a condensate of two molecules of monocarboxylic acid of formula (6), a condensate of polycarboxylic acid of formula (5) and monocarboxylic acid of formula (6), Unreacted products of polyvalent carboxylic acid and monocarboxylic acid, and by-products such as acid anhydrides formed by condensation reaction of a reaction reagent such as acetic anhydride and propionic anhydride with polyvalent carboxylic acid or monocarboxylic acid May contain objects. These by-products may be removed by purification, or may be used as a curing agent in a mixture.

  In addition, (B) hardening | curing agent may further contain the acid anhydride formed by polycyclic carboxylic acid ring-closing condensation in a molecule | numerator. In this case, the equivalent ratio of (A) the epoxy group contained in the epoxy resin and the acid anhydride group in the (B) curing agent capable of reacting with the epoxy group is 1: 0.3 to 1: 1.2. It is preferable that Thereby, the resin stain | pollution | contamination at the time of shaping | molding of a thermosetting resin composition can be reduced further.

  In the thermosetting resin composition, as the (B) curing agent, a curing agent generally used in an epoxy resin molding material for electronic component sealing can be used in combination with the polyvalent carboxylic acid condensate. Such a curing agent is not particularly limited as long as it reacts with the epoxy resin, but is preferably colorless or light yellow. Examples of such a curing agent include an acid anhydride curing agent, an isocyanuric acid derivative curing agent, and a phenol curing agent. Examples of the acid anhydride curing agent include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl nadic anhydride, nadic anhydride, glutaric anhydride. Examples include acid, dimethyl glutaric anhydride, diethyl glutaric anhydride, succinic anhydride, methyl hexahydrophthalic anhydride, and methyl tetrahydrophthalic anhydride. Isocyanuric acid derivatives include 1,3,5-tris (1-carboxymethyl) isocyanurate, 1,3,5-tris (2-carboxyethyl) isocyanurate, 1,3,5-tris (3-carboxypropyl) ) Isocyanurate, 1,3-bis (2-carboxyethyl) isocyanurate. Among these curing agents, phthalic anhydride, trimellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, glutaric anhydride, dimethylglutaric anhydride, anhydrous It is preferable to use diethyl glutaric acid or 1,3,5-tris (3-carboxypropyl) isocyanurate. Moreover, the said hardening | curing agent may be used individually by 1 type or in combination of 2 or more types. When these curing agents that can be used in combination are included, the viscosity of the (B) curing agent as a whole can be adjusted by changing the blending ratio with the polyvalent carboxylic acid condensate, which is preferable.

  From the viewpoint of further improving the alkali resistance of the cured product formed from the thermosetting resin composition, (B) the curing agent is tetrahydrophthalic anhydride which is a compound represented by the following formula (2) or the following formula ( It may further contain trimellitic anhydride which is a compound represented by 3).

  The above-described curing agent that can be used in combination preferably has a molecular weight of 100 to 400. In addition, an anhydride obtained by hydrogenating all unsaturated bonds of an aromatic ring is preferable to an acid anhydride having an aromatic ring such as trimellitic anhydride or pyromellitic anhydride. As the acid anhydride curing agent, an acid anhydride generally used as a raw material for the polyimide resin may be used.

  The viscosity of the curing agent measured by an ICI cone plate viscometer is preferably 1.0 to 1000 mPa · s at 150 ° C., and more preferably 10 to 200 mPa. When the viscosity of the curing agent is within the specific range, good moldability can be obtained, for example, the occurrence of burrs is suppressed when the thermosetting resin composition containing the curing agent is used for transfer molding. The viscosity of the curing agent is, for example, that of Research Equipment (London) LTD. It can be measured using a manufactured ICI cone plate viscometer. As a method of adjusting the viscosity of the curing agent, a method of adjusting the viscosity of the polyvalent carboxylic acid condensate itself by controlling the average molecular weight of the polyvalent carboxylic acid condensate, or a combination with the polyvalent carboxylic acid condensate can be used. The method of adjusting the compounding ratio with another hardening | curing agent is mentioned.

  The (B) curing agent is at least one selected from the group consisting of the compound represented by the general formula (1), the compound represented by the above formula (2), and the compound represented by the above formula (3). It may be an acid anhydride. (B) When the curing agent contains at least one of the compounds represented by the above (1) to (3), the thermosetting resin composition is sufficiently excellent in moldability and excellent in alkali resistance, A cured product with sufficiently reduced elution of the resin component can be formed.

  In the thermosetting resin composition, the blending amount of the (B) curing agent is preferably 10 to 150 parts by mass with respect to 100 parts by mass of the (A) epoxy resin, from the viewpoint of suppressing resin stains. More preferably, it is 50-120 mass parts.

  Further, (B) the curing agent has an active group (an acid anhydride group or a hydroxyl group) in (B) the curing agent capable of reacting with the epoxy group with respect to 1 equivalent of the epoxy group in (A) the epoxy resin. It is preferable to mix | blend so that it may become 0.5-0.9 equivalent, and it is more preferable that it will be 0.7-0.8 equivalent. If the said active group is less than 0.5 equivalent, while the cure rate of a thermosetting resin composition will become slow, the glass transition temperature of the hardened | cured material obtained will become low, and there exists a tendency for sufficient elasticity modulus to become difficult to be obtained. On the other hand, when the active group exceeds 0.9 equivalent, the strength after curing tends to decrease.

<(C) Curing accelerator>
(C) A curing accelerator can be blended in the thermosetting resin composition as required. (C) As a hardening accelerator, if it has a catalyst function which accelerates | stimulates hardening reaction between (A) and (B) component, it can use without being specifically limited. Examples of the curing accelerator include amine compounds, imidazole compounds, organic phosphorus compounds, alkali metal compounds, alkaline earth metal compounds, and quaternary ammonium salts. Among these curing accelerators, it is preferable to use an amine compound, an imidazole compound, or an organic phosphorus compound. Examples of the amine compound include 1,8-diaza-bicyclo (5,4,0) undecene-7, triethylenediamine, and tri-2,4,6-dimethylaminomethylphenol. Examples of the imidazole compound include 2-ethyl-4-methylimidazole. Furthermore, examples of the organic phosphorus compound include triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetra-n-butylphosphonium-o, o-diethylphosphorodithioate, tetra-n-butylphosphonium-tetrafluoroborate, tetra -N-butylphosphonium-tetraphenylborate. These curing accelerators may be used alone or in combination of two or more.

  The blending amount of the (C) curing accelerator is preferably 0.01 to 8 parts by mass and more preferably 0.1 to 3 parts by mass with respect to 100 parts by mass of the (A) epoxy resin. . If the content of the curing accelerator is less than 0.01 parts by mass, a sufficient curing acceleration effect may not be obtained, and if it exceeds 8 parts by mass, discoloration may be seen in the resulting molded article.

<(D) White pigment>
When used as a white molding resin that can be used in an optical semiconductor device or the like, it is preferable that the thermosetting resin composition further contains (D) a white pigment. (D) As a white pigment, a well-known thing can be used and it does not specifically limit. Examples of the white pigment include alumina, magnesium oxide, antimony oxide, titanium oxide, zirconium oxide, and inorganic hollow particles. These can be used alone or in combination of two or more. Examples of the inorganic hollow particles include sodium silicate glass, aluminum silicate glass, borosilicate soda glass, and shirasu (white sand). The white pigment preferably has a center particle size of 0.1 to 50 μm. If the center particle size is less than 0.1 μm, the particles tend to aggregate and the dispersibility tends to decrease, and if it exceeds 50 μm, it is difficult to sufficiently obtain the reflection characteristics of the cured product made of the thermosetting resin composition. .

  (D) Although the compounding quantity of a white pigment is not specifically limited, It is preferable that it is 10-85 volume% with respect to the whole thermosetting resin composition, and it is more preferable that it is 20-75 volume%. If the blending amount is less than 10% by volume, the light-reflecting properties of the cured thermosetting resin composition tend not to be sufficiently obtained. There is a tendency to decrease.

  Moreover, when a thermosetting resin composition contains the inorganic filler mentioned later with (D) white pigment, the total compounding quantity of (D) white pigment and an inorganic filler is with respect to the whole thermosetting resin composition. And the moldability of a thermosetting resin composition can be further improved as it is 10 to 85 volume%.

<Other ingredients>
(Inorganic filler)
The thermosetting resin composition preferably contains an inorganic filler in order to adjust moldability. In addition, you may use the thing similar to the said white pigment as an inorganic filler. Examples of inorganic fillers include silica, antimony oxide, titanium oxide, aluminum hydroxide, magnesium hydroxide, barium sulfate, magnesium carbonate, barium carbonate, alumina, mica, beryllia, barium titanate, potassium titanate, strontium titanate, Examples include calcium titanate, aluminum carbonate, aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay such as calcined clay, talc, aluminum borate, aluminum borate, and silicon carbide. From the viewpoint of thermal conductivity, light reflection characteristics, moldability and flame retardancy, the inorganic filler is selected from the group consisting of silica, alumina, magnesium oxide, antimony oxide, titanium oxide, zirconium oxide, aluminum hydroxide, and magnesium hydroxide. A mixture of two or more selected is preferable. The average particle diameter of the inorganic filler is preferably 1 to 100 μm, more preferably 1 to 40 μm, from the viewpoint of improving packing properties with the white pigment. It is preferable that the compounding quantity of the inorganic filler in a thermosetting resin composition is 1-1000 mass parts with respect to 100 mass parts of total amounts of (A) component and (B) component, and 1-800 mass parts. It is more preferable that

(Coupling agent)
In the thermosetting resin composition, the viewpoint of improving the adhesiveness between the components (A) to (C), which are thermosetting resin components, and (D) the white pigment and the inorganic filler added as necessary. It is preferable to add a coupling agent. Although it does not specifically limit as a coupling agent, For example, a silane coupling agent and a titanate coupling agent are mentioned. Examples of the silane coupling agent generally include epoxy silane, amino silane, cationic silane, vinyl silane, acryl silane, mercapto silane, and composites thereof, and can be used in any amount. In addition, it is preferable that the compounding quantity of a coupling agent is 5 mass% or less with respect to the whole thermosetting resin composition.

  Moreover, you may add additives, such as antioxidant, a mold release agent, and an ion trapping agent, to a tree thermosetting fat composition as needed.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not limited to a following example.

<Preparation of polyvalent carboxylic acid condensate>
The synthesis of Synthesis Examples A1 and A2 was carried out by refluxing the following monomer for repeating unit and monomer for both ends in acetic anhydride for 5 to 60 minutes under a nitrogen atmosphere, and then increasing the temperature to 180 ° C. Acetic acid and water produced by the reaction in an open system were distilled off under an air stream. When no volatile components were observed, the reaction vessel was decompressed and melt condensed at a temperature of 180 ° C. for 1 to 15 hours to obtain a polyvalent carboxylic acid condensate.

(Synthesis Example A1)
Repeating unit: hydrogenated terephthalic acid (manufactured by Tokyo Chemical Industry Co., Ltd.); 125 g
Both ends: 1,2-trimellitic anhydride (manufactured by Mitsubishi Gas Chemical Company); 126 g.
(Synthesis Example A2)
Repeating unit: hydrogenated terephthalic acid (manufactured by Tokyo Chemical Industry Co., Ltd.); 125 g
Both ends: Hydrogenated-1,2-trimellitic anhydride (manufactured by Mitsubishi Gas Chemical Company); 126 g.

<Preparation of Material 1>
Material 1 was prepared by mixing the following ingredients.
Triepoxypropyl isocyanurate (epoxy equivalent 100, manufactured by Nissan Chemical Co., Ltd., trade name: TEPIC-S): 20 parts by mass,
Synthesis Example A1: 3.6 parts by mass
Tetrahydrophthalic anhydride (trade name Ricacid TH manufactured by Shin Nippon Rika Co., Ltd.): 8.6 parts by mass,
Hexahydrophthalic anhydride (trade name Ricacid HH, manufactured by Shin Nippon Chemical Co., Ltd.): 8.6 parts by mass,
Tetra-n-butylphosphonium tetraphenylborate (manufactured by Nippon Chemical Industry Co., Ltd., trade name: PX-4PB): 0.7 parts by mass,
Trimethoxyepoxysilane (manufactured by Toray Dow Corning, trade name: S6040): 0.5 part by mass,
Fused silica A (manufactured by Denki Kagaku Kogyo, trade name: FB-950): 75 parts by mass,
Fused silica B (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name: S0-25R): 19 parts by mass,
Hollow particles (manufactured by Sumitomo 3M, trade name: S60-HS): 26 parts by mass,
Titanium oxide (made by Ishihara Sangyo Co., Ltd., trade name: CR63): 89 parts by mass.

<Preparation of Material 2>
Material 2 was prepared by mixing the following ingredients.
Triepoxypropyl isocyanurate (epoxy equivalent 100, manufactured by Nissan Chemical Co., Ltd., trade name: TEPIC-S): 20 parts by mass,
Synthesis Example A2: 3.7 parts by mass Hexahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd., trade name Ricacid HH): 21 parts by mass
Tetra-n-butylphosphonium tetraphenylborate (manufactured by Nippon Chemical Industry Co., Ltd., trade name: PX-4PB): 0.7 parts by mass,
Trimethoxyepoxysilane (manufactured by Toray Dow Corning, trade name: S6040): 0.5 part by mass,
Fused silica A (manufactured by Denki Kagaku Kogyo, trade name: FB-950): 75 parts by mass,
Fused silica B (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name: S0-25R): 19 parts by mass,
Hollow particles (manufactured by Sumitomo 3M, trade name: S60-HS): 26 parts by mass,
89 parts by mass of titanium oxide (made by Ishihara Sangyo Co., Ltd., trade name: CR63).

<Pulverization treatment of resin material>
Example 1
A screen having the configuration shown in FIG. 2 (inner diameter 250 mm, main body thickness 2 mm, opening φ3 mm, hole pitch 4.5 mm, taper angle (angle α) 60 °) was prepared. This screen was attached to a power mill (trade name: P-5, manufactured by Dalton Co., Ltd.), and the materials 1 and 2 were pulverized.

(Example 2)
In place of the screen shown in FIG. 1, the screen shown in FIG. 5 (inner diameter 250 mm, main body thickness 2 mm, opening slit width 3 mm, slit pitch 4.5 mm, taper angle 60 °) is mounted on the power mill. Except for this, the materials 1 and 2 were pulverized in the same manner as in Example 1.

(Example 3)
In place of the screen having the configuration shown in FIG. 1, the screen having the configuration shown in FIG. 7 (inner diameter 250 mm, body portion thickness 2 mm, opening slit width 3 mm, slit pitch 4.5 mm, taper portion angle 60 °, slit inclination angle ( The materials 1 and 2 were pulverized in the same manner as in Example 1 except that the angle β) 30 °) was mounted on the power mill.

Example 4
Instead of the screen having the configuration shown in FIG. 1, the screen having the configuration shown in FIG. 8 (inner diameter 250 mm, body portion thickness 2 mm, opening slit width 3 mm, slit pitch 4.5 mm, taper portion angle 60 °) was mounted on the power mill. Except for this, the materials 1 and 2 were pulverized in the same manner as in Example 1.

(Comparative Example 1)
In place of the screen having the configuration shown in FIG. 1 except that the conventional screen having the configuration shown in FIG. 9 (inner diameter 250 mm, main body thickness 2 mm, opening φ3 mm, hole pitch 4.5 mm) is mounted on the power mill. In the same manner as in Example 1, the materials 1 and 2 were pulverized.

<Evaluation items>
The screens used in Examples 1 to 4 and Comparative Example 1 were evaluated for the following items. Table 1 shows the results.
(1) Ejectability of resin material Evaluation was performed based on the amount of resin material discharged from the power mill.
A: Very good,
B: Good,
C: Bad.
(2) Presence / absence of clogging of screen The screen was taken out from the power mill after the pulverization treatment, and the surface of the screen was visually observed.
A: No adhesion,
B: Slight adhesion
C: Adhering in large quantities.
(3) Screen cleanability Evaluation was performed based on the time required for cleaning the screen taken out of the power mill.
A: No need to clean,
B: Easy cleaning
C: Cleaning is difficult.

1, 2, 3, 4 ... screen, 1a, 2a, 3a, 4a ... main body, 1b, 2b, 3b, 4b ... opening, 1c, 2c, 3c, 4c ... taper, 20 ... resin material crusher, 22: Rotating feathers, F1: Inner surface of the screen, F2: Outer surface of the screen.

Claims (5)

A screen installed on the outer side of the rotary feather of the resin material crusher,
A tubular body,
A plurality of openings penetrating from the inner surface to the outer surface of the main body,
With
The said opening part is a screen which has a taper part which opening size expands toward the outer surface from the inner surface of the said main-body part.   2. The screen according to claim 1, wherein the opening has a circular cross-sectional shape perpendicular to a direction from the inner surface to the outer surface of the main body.   The screen according to claim 1, wherein the opening is provided in a slit shape.   The screen according to claim 3, wherein an angle formed by the axial direction of the main body and the longitudinal direction of the slit-shaped opening is 0 to 90 °. A method for grinding a resin material,
A step of supplying a resin material to a resin pulverizer comprising a rotary blade and the screen according to any one of claims 1 to 4 installed outside the rotary blade;
Crushing the resin material in the rotary blade and the tapered portion of the screen;
A method comprising:

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