JP4099034B2 - Thermosetting molding material for press-fitting molded products and molded products - Google Patents

Description

【００４１】
これら実施例、比較例より、ショアーＤ硬度が９０以下の場合に圧入性に問題ない成形品が得られることが判る。また、薄い隙間への充填は成形材料の針入度が３０以下の場合には充填不良が生じることが判る。
圧入性に優れた成形品を得るには、ショアーＤ硬度は９０以下とする必要があり、薄い隙間への充填性がありかつ良好なハンドリング性を得るためには成形材料の針入度は３０〜１５０である必要がある。
【００４２】
【発明の効果】
本発明の成形材料は、薄い隙間にＢＭＣを用いて射出成形された成形物は、寸法精度が高く柔軟であることから、金属等からなる隙間に圧入可能であり、射出成形時に金属などの部品をインサート成形すれば、同部品を容易に圧入、固定することができる。
【００４３】
【図面の簡単な説明】
【図１】本発明の熱硬化性成形材料を使用した金属内包成形品の金属隙間への圧入嵌合を説明する図。
【図２】本発明の熱硬化性成形材料を使用した金属内包射出成形の概念を説明する図。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thermosetting molding material comprising an unsaturated polyester resin that forms a thermosetting molded article excellent in press-fitting properties. More specifically, the thermosetting molding material of the present invention can be thermoset by an injection molding method, and the thermoset injection molded product containing a metal piece or the like is placed in a gap of a predetermined dimension such as a metal. When inserting and fixing, the thermosetting injection-molded cured product has sufficient flexibility to enable press-fitting. Furthermore, a very thin protective layer of, for example, 30 to 100 μm is provided to avoid contact between the fixed concave wall surface and the metal piece or the like even in a portion that does not require press fit when enclosing the metal piece or the like. . Thus, the metal piece or the like contained in the thermosetting injection molded product can be press-fitted and fixed without the metal piece directly contacting the wall surface of the gap having a predetermined size.
More specifically, for example, a metal piece having a width of 40.0 mm, a height of 5.0 mm, and a depth of 45.0 mm is placed in a square hole made of a metal having an opening width of 50.0 mm, a height of 5.2 mm, and a depth of 50.0 mm. When the metal piece is intended to be fixed without being brought into contact with the wall of the square hole, the metal piece is heated in a mold cavity having a width of 50.5 mm, a thickness of 5.2 mm, and a depth of 50.0 mm. By accurately fixing in advance with a positioning jig, etc., and thermosetting molding material is injection-molded around it, a molded product with the same shape as the mold cavity containing the metal piece is obtained. It is fixed by press-fitting into a square hole (see FIGS. 1 and 2).
[0002]
[Prior art]
Bulk molding material using unsaturated polyester resin called BMC (Bulk Molding Compound) as thermosetting resin has excellent performance such as insulation, heat resistance and dimensional accuracy, handling and injection molding. It is widely used as a molding material with excellent productivity due to its properties. For example, electrical equipment parts and automobile headlamp reflectors are applications that take advantage of these characteristics, and are widely used regardless of domestic or overseas.
[0003]
However, since these BMCs for general use are required to be hard, the cured molded product lacks flexibility, and it is difficult to fit and fix it in a predetermined gap. When trying to fit forcefully, the BMC molded product is scraped off by metal, so that it becomes difficult to fix by a reaction force of press-fitting.
Therefore, the conventional BMC cannot be used as a molded product for such press fitting.
[0004]
[Problems to be solved by the invention]
Under such circumstances, the present invention provides a thermosetting molding material capable of injection molding using an unsaturated polyester resin, and particularly a molding material excellent in fitting and fixing by press-fitting and a cured molding product thereof. It is intended to do.
[0005]
[Means for Solving the Problems]
As a result of intensive studies on the press-fit property of molded products required for the same application and workability as a molding material, the present inventors have obtained the following knowledge.
(1) As a result of examining the hardness of the resin and the amount of inorganic filler and examining cured products of various hardnesses, it is possible to obtain molded products with excellent press-fitting properties by reducing the Shore D hardness to 90 or less. It is.
(2) To make the Shore D hardness 90 or less, it is necessary to blend a soft thermosetting resin having a double bond concentration of 2.0 mmol / g or less and a glass transition temperature of 70 ° C. or less. It is necessary to blend the resin at least 50 wt% of the total thermosetting resin on the basis of the solid content.
(3) The volume content of the total of inorganic fillers in the form of fibers such as glass fibers and aluminum hydroxide and calcium carbonate particles added to improve dimensional accuracy and strength exceeds 50 vol% of the entire molding material. And Shore D hardness becomes 90 or more, and press fit property is impaired.
(4) When the hardness of the molding material is less than 30, the fluidity is insufficient to fill a gap of 100 μm or less.
(5) When the hardness of the molding material exceeds 150 in terms of penetration, handling and injection molding machines are poor in measurement and not suitable for mass production.
(6) Therefore, the hardness of the molding material needs to be 30 or more and 150 or less in terms of penetration (JIS K 2235).
(7) In addition to chemical thickening by conventional alkaline earth metal oxides and hydroxides, physical thickening by thermoplastic resin particles can be used alone or in combination with chemical thickening. The material which shows the penetration of ▼ can be made.
[0006]
Based on these findings, the inventors have invented a molding material that has sufficient flexibility to allow the cured molding material to be press-fitted and the molding material before injection-curing molding is excellent in handling and mass productivity.
[0007]
That is, the present invention
1) An unsaturated polyester resin was used as the thermosetting resin. Can be thermoset by injection molding A thermosetting molding material comprising 50 wt% or more of the total thermosetting resin based on solid content, an unsaturated polyester resin having a double bond concentration of 2.0 mmol / g or less and a glass transition temperature of 70 ° C. or less. Yes The volume content of the total amount of fibrous and particulate inorganic filler is 50 vol% or less of the entire molding material, and the penetration of the molding material (JIS K 2235) is 30 to 150 (3 to 15 mm), For press-fitting molded products characterized by being able to form thermoset fitting molded products having excellent press-fit properties with a Shore D (ASTM D676-55T) hardness of 90 or less For injection molding Thermosetting molding material.
2) A thermosetting molding material capable of thermosetting molding by an injection molding method using an unsaturated polyester resin as a thermosetting resin at a molding temperature of 100 to 200 ° C. and a molding cycle of 5 minutes or less, 50% by weight or more of the total thermosetting resin based on solid content is an unsaturated polyester resin having a double bond concentration of 2.0 mmol / g or less and a glass transition temperature of 70 ° C. or less. The volume content of the total material is 50 vol% or less of the entire molding material, and the penetration of the molding material (JIS K 2235) is 30 to 150 (3 to 15 mm), For press-fitting molded products characterized by being able to form thermoset fitting molded products having excellent press-fit properties with a Shore D (ASTM D676-55T) hardness of 90 or less For injection molding Thermosetting molding material.
3 1) For press-fitting molded products according to 1) or 2) above, wherein thermoplastic resin particles are added as a physical thickener. For injection molding Thermosetting resin molding material,
4 1) to above 3 ) A press-fitting molded product formed by molding the thermosetting molding material according to any one of
It becomes more.
[0008]
In addition, said solid content reference | standard shows only the solid content which does not contain the vinyl monomer in unsaturated polyester resin.
The glass transition temperature was determined from the temperature at which the loss tangent of the dynamic viscoelasticity measurement was maximum.
Since the molding material of the present invention is excellent in mass production and fluidity in injection molding, the molding material can sufficiently flow into a gap of 100 microns or less, and includes a metal piece that requires press-fitting. It is effective as a molding material for molding products.
[0009]
For example, the upper and lower surfaces of metal pieces having flat surfaces are disposed, and the thermosetting molding material of the present invention is injection-molded in a mold cavity heated to 100 to 200 ° C. A heat-cured resin layer having a predetermined thickness can be formed on the peripheral surface and the lower surface. At that time, since the thermosetting molding material of the present invention has good flowability at the time of molding, a very thin resin film of 30 to 100 microns is also formed on the upper surface other than the peripheral surface and the lower surface molded with the thermoset resin. Can be formed. This thin resin film functions as a protective film for the molded metal piece (see FIGS. 1 and 2).
[0010]
The unsaturated polyester used in the present invention is synthesized by condensation of an α, β-olefinic unsaturated dicarboxylic acid and a divalent glycol. In addition to these two components, a saturated dicarboxylic acid, an aromatic dicarboxylic acid, dicyclopentadiene that reacts with a dicarboxylic acid, or the like can be used in combination for the synthesis of the polyester.
[0011]
Examples of the α, β-olefin unsaturated carboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, and anhydrides of these dicarboxylic acids. Examples of dicarboxylic acids used in combination with these α, β-olefin dicarboxylic acids include, for example, adipic acid, sebacic acid, succinic acid, gluconic acid, phthalic anhydride, o-phthalic acid, isophthalic acid, terephthalic acid, tetrahydro Examples include phthalic acid and tetrachlorophthalic acid.
[0012]
Examples of the divalent glycol include alkanediol, oxaalkanediol, and diol obtained by adding alkylene oxide such as ethylene oxide and propylene oxide to bisphenol A. In addition, monool or trivalent triol may be used.
[0013]
Examples of alkanediols include, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, Examples include 1,6-hexanediol and cyclohexanediol.
[0014]
Examples of the oxaalkanediol include dioxyethylene glycol and triethylene glycol. Examples of the monovalent or trivalent alcohol used in combination with these glycols include octyl alcohol, oleyl alcohol, and trimethylolpropane. The synthesis of unsaturated polyester is generally carried out under heating, and the reaction proceeds while removing by-product water.
[0015]
In general, unsaturated polyester should have a low cross-linking density depending on the raw material used, and a raw material having a long-chain molecular structure such as adipic acid, sebacic acid, or glycol, such as diethylene glycol or propylene glycol, should be used. Thus, a soft resin having a low glass transition temperature can be obtained. On the other hand, a resin having a high glass transition temperature can be obtained by increasing the crosslink density and using a raw material having a rigid structure such as hydrogenated bisphenol A as the raw material used.
[0016]
A soft thermosetting resin having a double bond concentration of 2.0 mmol / g or less, preferably 0.2 mmol / g or more and 1.0 mmol / g or less and a glass transition temperature of 70 ° C. or less is based on solid content. It is necessary to contain 50 wt% or more of the total thermosetting resin, and more preferably 80 to 100 wt%. If the content of the resin is less than 50 wt%, the thermosetting molding material cured product becomes too hard to obtain press fit, and the glass transition temperature of the unsaturated polyester resin used in combination at 50 to 80 wt% is too high. If it is very high, the thermosetting molding material cured product may be too hard to obtain press fit.
The heat-cured press-fitting molded product of the present invention has a Shore D (ASTM D676-55T) hardness of 90 or less, preferably 40-90. Moreover, the thermosetting molding material before the curing has a penetration (JIS K2235) of 30 to 150 (3 to 15 mm), preferably 50 to 120.
[0017]
The vinyl monomer used in the present invention is a monovinyl monomer conventionally used as a diluent or crosslinking agent for unsaturated polyester, for example, an aromatic monovinyl monomer such as styrene, p-chlorostyrene, vinyltoluene and the like. And acrylic monovinyl monomers such as acrylic acid, acrylic acid methyl ester, methacrylic acid, methacrylic acid methyl ester, and acrylonitrile, with styrene being particularly preferred. This vinyl monomer is usually blended into unsaturated polyester and thermoplastic resin as a diluent for unsaturated polyester and thermoplastic resin.
[0018]
The thermosetting molding material of the present invention contains particulate and fibrous inorganic fillers other than the above, a low shrinkage agent, a curing agent, a curing regulator, a pigment, an internal release agent, and a thickener as necessary. can do.
Examples of the particulate inorganic filler include calcium carbonate and aluminum hydroxide. Examples of the fibrous inorganic filler include glass fibers having an aspect ratio of 10 or more, vinylon fibers, carbon fibers, and aramid fibers. Particularly, chopped glass fibers having a fiber length of 50 μm to 25 mm are preferable, and the fiber length is about 1 to 3 mm. The thing is more preferable from the point of the moldability and the reinforcing effect of the present invention.
[0019]
The blending amount of the particulate and fibrous inorganic filler greatly affects the handling of the molding material of the present invention, the moldability and the hardness of the cured product, and the volume content of the total amount of the inorganic filler is 0 to 0 of the entire molding material. 50 vol% is preferable, and 20 to 40 vol% is more preferable. When the total amount of the inorganic filler exceeds 50 vol%, the hardness of the cured product becomes too hard to obtain press fit. When the total amount of the inorganic filler is as small as 20 vol% or less, although it is possible to obtain a molding material exhibiting the desired handling and moldability by adjusting the thickening of other organic components, the adjustment tends to be strict. Adjustment of the molding material is easier when 20 vol% or more is blended.
[0020]
As a low shrinkage agent, a vinyl polymer, a rubber polymer comprising a polymer block comprising a vinyl aromatic compound in saturated polyester, styrene, etc. and a polymer block comprising a conjugated diene compound such as butadiene, isoprene, etc. , Polystyrene, partially cross-linked polystyrene, acrylic polymer, polyethylene, and the like.
[0021]
In the present invention, the low shrinkage agent is added in order to obtain the original low shrinkage effect, but vinyl acetate is a relatively soft low shrinkage agent in view of the press fit of the cured product. Polymers, saturated polyesters, rubber-based polymers, and the like are preferable, and vinyl acetate polymers and saturated polyesters that are excellent in compatibility with unsaturated polyester resins are more preferable. The addition amount of the low shrinkage agent is preferably 0 to 50 parts by weight in 100 parts by weight of the mixture of unsaturated polyester, vinyl monomer and thermoplastic resin.
[0022]
Curing agents include t-butyl peroxybenzoate, peroxyesters represented by t-butyl peroctoate, and 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane. Peroxyketals, peroxycarbonates typified by t-butylperoxyisopropyl carbonate, etc., and at least one kind is used with respect to 100 parts by weight of a mixture of unsaturated polyester, vinyl monomer and thermoplastic resin. 0.5 to 5 parts by weight, preferably 1 to 3 parts by weight is used.
[0023]
Examples of the curing regulator include parabenzoquinone and t-butylcatechol. Examples of the pigment include carbon black, titanium oxide, petiole, and phthalocyanine blue. The internal mold release agent can be used depending on the mold release property and the molding temperature, and examples thereof include zinc stearate, calcium stearate, and stearic acid.
[0024]
As the thickener, general chemical thickeners and physical thickeners can be used alone or in combination. Examples of the chemical thickener include oxides or hydroxides such as magnesium and calcium. The chemical thickening method of the unsaturated polyester needs to be controlled by the chemical properties such as the acid value of the unsaturated polyester and the water and chemical thickener addition amount in the system.
[0025]
As the physical thickener, for example, a resin powder containing at least 50 wt% of at least one monomer unit selected from the acrylic acid esters, methacrylic acid esters, and aromatic vinyl compounds described in WO96 / 00753. A thickening agent as an active ingredient can be mentioned, and any thickening agent having a physical thickening effect by the same mechanism can be used. The physical thickener is preferably added in an amount of 0 to 50 parts by weight in 100 parts by weight of a mixture of unsaturated polyester, vinyl monomer and thermoplastic resin containing the physical thickener. More preferably, parts by weight are added.
[0026]
In the physical thickening method, the speed of thickening and final thickening are controlled by the solubility parameters of other molding material components and physical thickeners and the amount of physical thickener added, but the effect of moisture is small. As a result, there are fewer uncertainties during the production of the molding material, and when the control of the hardness (penetration) of the molding material is strict as in the present invention, the physical thickener and the chemical thickener It can be said that combined use or single use is an effective means.
Using such various compounding agents, a molding material can be obtained by a conventional means and apparatus. Moreover, the molding material of this invention can manufacture a molding by heat-hardening (pressure 5-12 Mpa, temperature 100-200 degreeC) in a metal mold | die by compression and injection molding. In view of the molding cycle and insert molding of metal pieces, injection molding is most preferred.
[0027]
【Example】
Hereinafter, the present invention will be described more specifically with reference to specific examples.
[Synthesis example]
The synthesis example of the unsaturated polyester resin used for the Example below is shown.
[0028]
(1) Synthesis of unsaturated polyester resin A
An unsaturated polyester was prepared by reacting 2910 g of diethylene glycol, 422 g of maleic anhydride, 1050 g of adipic acid, 1083 g of orthophthalic acid, and 1215 g of isophthalic acid at a reaction temperature of 200 ° C. to an acid value of 15 by a conventional method. Unsaturated polyester resin A was obtained by mixing 67 parts by weight of styrene.
The double bond concentration of unsaturated polyester resin A was calculated to be 0.7 mmol / g, and the glass transition temperature by dynamic viscoelasticity was 48 ° C.
[0029]
(2) Synthesis of unsaturated polyester resin B
First, 5010 g of propylene glycol and 6250 g of isophthalic acid were subjected to a primary reaction at a reaction temperature of 200 ° C. to an acid value of 15 by a conventional method. Then, 2320 g of propylene glycol and 5530 g of maleic anhydride were added, and secondary reaction was carried out to a acid value of 20 at a reaction temperature of 200 ° C. The unsaturated polyester was adjusted by reacting, and 67 parts by weight of styrene was mixed with 100 parts by weight of the ester to obtain an unsaturated polyester resin B.
The double bond concentration of unsaturated polyester resin B was calculated to be 3.4 mmol / g, and the glass transition temperature by dynamic viscoelasticity was 160 ° C.
[0030]
Example 1
As shown in Table 1, with respect to 60 parts by weight of unsaturated polyester A, 40 parts by weight of polyvinyl acetate resin (Polymer 9966 manufactured by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxy 2-ethyl hexanoate (Perbutyl manufactured by NOF Corporation) O) 1 part by weight, 0.02 part by weight of parabenzoquinone, 3 parts by weight of zinc stearate, 0.50 part by weight of magnesium oxide were dispersed and stirred, and then the resin liquid was put into a general-purpose planetary mixer. After 100 parts by weight of aluminum oxide particles (Nippon Light Metal Co., Ltd. fine-grain aluminum hydroxide B-103) were added and uniformly dispersed by kneading for 5 minutes, chopped glass fiber (RES015-BM47 manufactured by Nippon Sheet Glass Co., Ltd.) 30 weights After adding 5 parts and kneading for 5 minutes, A molding material was obtained after aging for 24 hours.
The finished molding material has good handling, and when it is injection-molded in a 60-second cycle using an injection molding machine and a mold whose temperature is adjusted to 140 ° C., it can be filled into gaps of 30 μm and 100 μm, and the obtained molding The press-fit property of the product was good.
[0031]
Example 2
As shown in Table 1, with respect to 40 parts by weight of unsaturated polyester resin A, 20 parts by weight of unsaturated polyester resin B, 40 parts by weight of polyvinyl acetate resin (polymer 9966 made by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxide 2 -Ethyl hexanoate (Nippon Yushi Co., Ltd. Perbutyl O) 1 part by weight, parabenzoquinone 0.02 part by weight, zinc stearate 3 parts by weight, magnesium oxide 0.50 part by weight was dispersed and stirred, and then a general-purpose planetary mixer was used. After adding the resin solution, 100 parts by weight of aluminum hydroxide particles (Nippon Light Metal Co., Ltd. fine-grained aluminum hydroxide B-103) was added to the mixer and uniformly dispersed by kneading for 5 minutes, and then chopped glass fiber ( Nippon Plate Glass Co., Ltd. RES015-BM47) 30 parts by weight After you and kneaded for 5 minutes to obtain a molding material through the aging of the kneaded mixture 40 ° C. × 24 hours.
The finished molding material has good handling, and when it is injection-molded in a 60-second cycle using an injection molding machine and a mold whose temperature is adjusted to 140 ° C., it can be filled into gaps of 30 μm and 100 μm, and the obtained molding The press-fit property of the product was good.
[0032]
Example 3
As shown in Table 1, with respect to 60 parts by weight of unsaturated polyester resin A, 40 parts by weight of polyvinyl acetate resin (Polymer 9966 manufactured by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxy 2-ethyl hexanoate (manufactured by NOF Corporation) 1 part by weight of perbutyl O), 0.02 part by weight of parabenzoquinone, 3 parts by weight of zinc stearate, 0.50 part by weight of magnesium oxide were dispersed and stirred, and then the resin liquid was put into a general-purpose planetary mixer. After adding 50 parts by weight of aluminum hydroxide particles (Nihon Light Metal Co., Ltd. fine-grained aluminum hydroxide B-103), the mixture was uniformly dispersed by kneading for 5 minutes, and then chopped glass fiber (RES015-BM47 manufactured by Nippon Sheet Glass Co., Ltd.). After adding 30 parts by weight and kneading for 5 minutes, To obtain a molding material through the aging 0 ° C. × 24 hours.
The finished molding material has good handling, and when it is injection-molded in a 60-second cycle using an injection molding machine and a mold whose temperature is adjusted to 140 ° C., it can be filled into gaps of 30 μm and 100 μm, and the obtained molding The press-fit property of the product was good.
[0033]
Example 4
As shown in Table 1, with respect to 60 parts by weight of unsaturated polyester resin A, 30 parts by weight of polyvinyl acetate resin (polymer 9966 made by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxy 2-ethyl hexanoate (manufactured by NOF Corporation) 1 part by weight of perbutyl O) 0.02 part by weight of parabenzoquinone, 3 parts by weight of zinc stearate, 0.25 part by weight of magnesium oxide were dispersed and stirred, and a physical thickener (polymethyl methacrylate particles manufactured by Nippon Zeon Co., Ltd.) F320) After adding and dispersing and stirring 10 parts by weight, the resin liquid was put into a general-purpose planetary mixer, and then aluminum hydroxide particles (fine aluminum hydroxide B-103 manufactured by Nippon Light Metal Co., Ltd.) 100 parts by weight. And then uniformly dispersed by kneading for 5 minutes, and then chopped glass fiber Bar (Nippon Sheet Glass Co., Ltd. RES015-BM47) after kneading of the added 5 minutes 30 parts by weight, to obtain a molding material through the aging of the kneaded mixture 40 ° C. × 24 hours.
The finished molding material has good handling, and when it is injection-molded in a 60-second cycle using an injection molding machine and a mold whose temperature is adjusted to 140 ° C., it can be filled into gaps of 30 μm and 100 μm, and the obtained molding The press-fit property of the product was good.
[0034]
Example 5
As shown in Table 1, with respect to 60 parts by weight of unsaturated polyester resin A, 20 parts by weight of polyvinyl acetate resin (polymer 9966 made by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxy 2-ethyl hexanoate (manufactured by NOF Corporation) 1 part by weight of perbutyl O) 0.02 part by weight of parabenzoquinone and 3 parts by weight of zinc stearate are dispersed and stirred, and further 20 parts by weight of a physical thickener (polymethyl methacrylate particles F320 manufactured by ZEON CORPORATION) are added and dispersed. After stirring, the resin solution is put into a general-purpose planetary mixer, and then 100 parts by weight of aluminum hydroxide particles (fine aluminum hydroxide B-103 manufactured by Nippon Light Metal Co., Ltd.) are added to the mixer, followed by kneading for 5 minutes. After uniform dispersion, chopped glass fiber (RES manufactured by Nippon Sheet Glass Co., Ltd.) 015-BM47) After adding 30 parts by weight and kneading for 5 minutes, the kneaded product was aged at 40 ° C. for 24 hours to obtain a molding material.
The finished molding material has good handling, and when it is injection-molded in a 60-second cycle using an injection molding machine and a mold whose temperature is adjusted to 140 ° C., it can be filled into gaps of 30 μm and 100 μm, and the obtained molding The press-fit property of the product was good.
[0035]
Comparative Example 1
As shown in Table 1, with respect to 60 parts by weight of unsaturated polyester resin B, 40 parts by weight of polyvinyl acetate resin (Polymer 9966 manufactured by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxy 2-ethyl hexanoate (manufactured by NOF Corporation) 1 part by weight of perbutyl O), 0.02 part by weight of parabenzoquinone, 3 parts by weight of zinc stearate, 0.50 part by weight of magnesium oxide were dispersed and stirred, and then the resin liquid was put into a general-purpose planetary mixer. After adding 100 parts by weight of aluminum hydroxide particles (Nippon Light Metal Co., Ltd., fine-grain aluminum hydroxide B-103) and uniformly dispersing by kneading for 5 minutes, chopped glass fiber (RES015-BM47 manufactured by Nippon Sheet Glass Co., Ltd.) After adding 30 parts by weight and kneading for 5 minutes, the kneaded product To obtain a molding material through the aging 40 ° C. × 24 hours.
The finished molding material has good handling, and when it was injection-molded in a 60-second cycle with an injection molding machine and a mold temperature-controlled at 140 ° C., filling into gaps of 30 μm and 100 μm was possible, When press-fitting, manual press-fitting was impossible, and when trying to press-fit with a hammer, the molded part was damaged and could not be pressed.
[0036]
Comparative Example 2
As shown in Table 1, with respect to 20 parts by weight of unsaturated polyester resin A, 40 parts by weight of unsaturated polyester resin B 40 parts by weight of polyvinyl acetate resin (Polymer 9966 manufactured by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxide 2- Ethyl hexanoate (Nippon Yushi Co., Ltd., Perbutyl O) 1 part by weight, parabenzoquinone 0.02 part by weight, zinc stearate 3 parts by weight, magnesium oxide 0.50 part by weight was dispersed and stirred. After adding the resin liquid, 100 parts by weight of aluminum hydroxide particles (Nippon Light Metal Co., Ltd. fine-grain aluminum hydroxide B-103) was added to the mixer and dispersed uniformly by kneading for 5 minutes, and then chopped glass fiber (Japan Plate glass Co., Ltd. RES015-BM47) Add 30 parts by weight After kneading for 5 minutes to obtain a molding material through the aging of the kneaded mixture 40 ° C. × 24 hours.
The finished molding material has good handling, and when it was injection-molded in a 60-second cycle with an injection molding machine and a mold temperature-controlled at 140 ° C., filling into gaps of 30 μm and 100 μm was possible, When press-fitting, manual press-fitting was impossible, and when trying to press-fit with a hammer, the molded part was damaged and could not be pressed.
[0037]
Comparative Example 3
As shown in Table 1, 40 parts by weight of polyvinyl acetate resin (Polymer 9966 made by Mitsui Takeda Chemical Co., Ltd.), 60 parts by weight of unsaturated polyester resin A, t-Butyl peroxy 2-ethyl hexanoate (Perbutyl, manufactured by NOF Corporation) O) 1 part by weight, 0.02 part by weight of parabenzoquinone, 3 parts by weight of zinc stearate, 0.50 part by weight of magnesium oxide were dispersed and stirred, and then the resin liquid was put into a general-purpose planetary mixer. Aluminum hydroxide particles (Nippon Light Metal Co., Ltd. fine-grain aluminum hydroxide B-103) 300 parts by weight were added and dispersed uniformly by kneading for 5 minutes, and then chopped glass fiber (Nippon Sheet Glass Co., Ltd. RES015-BM47) 30 After adding parts by weight and kneading for 5 minutes, To obtain a molding material through the aging 0 ° C. × 24 hours.
The finished molding material is also easy to handle. When injection molding is performed in a 60-second cycle using an injection molding machine and a mold whose temperature is adjusted to 140 ° C., filling defects in the gaps of 30 μm and 100 μm occur. However, manual press-fitability was impossible, and when press-fitting was attempted with a hammer, the molded part was damaged and could not be press-fitted.
[0038]
Comparative Example 4
As shown in Table 1, with respect to 60 parts by weight of unsaturated polyester A, 40 parts by weight of polyvinyl acetate resin (Polymer 9966 manufactured by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxy 2-ethyl hexanoate (Perbutyl manufactured by NOF Corporation) O) 1 part by weight, 0.02 part by weight of parabenzoquinone, 3 parts by weight of zinc stearate, 2.0 parts by weight of magnesium oxide were dispersed and stirred, and then the resin liquid was put into a general-purpose planetary mixer. Aluminum hydroxide particles (Nippon Light Metal Co., Ltd. fine-grain aluminum hydroxide B-103) 100 parts by weight were added and uniformly dispersed by kneading for 5 minutes, and then chopped glass fiber (Nippon Sheet Glass Co., Ltd. RES015-BM47) 30 After adding parts by weight and kneading for 5 minutes, × obtain a molding material through aging 24 hours.
The finished molding material has good handling, and injection molding was performed in a 60-second cycle using an injection molding machine and a mold temperature-controlled at 140 ° C., which resulted in poor filling in gaps of 30 μm and 100 μm. There was no problem. Although the molding material is sufficient for the purpose of press-fitting only, there is a problem when excellent moldability is required.
[0039]
Comparative Example 5
As shown in Table 1, with respect to 60 parts by weight of unsaturated polyester A, 40 parts by weight of polyvinyl acetate resin (Polymer 9966 manufactured by Mitsui Takeda Chemical Co., Ltd.), t-Butyl peroxy 2-ethyl hexanoate (Perbutyl manufactured by NOF Corporation) O) 1 part by weight, 0.02 part by weight of parabenzoquinone, 3 parts by weight of zinc stearate, 0.05 part by weight of magnesium oxide were dispersed and stirred, and then the resin liquid was put into a general-purpose planetary mixer. Aluminum hydroxide particles (Nippon Light Metal Co., Ltd. fine-grain aluminum hydroxide B-103) 100 parts by weight were added and uniformly dispersed by kneading for 5 minutes, and then chopped glass fiber (Nippon Sheet Glass Co., Ltd. RES015-BM47) 30 After adding parts by weight and kneading for 5 minutes, To obtain a molding material through the aging ° C. × 24 hours.
I tried injection molding in a 60-second cycle with an injection molding machine and a mold controlled at 140 ° C, and the molding material had a problem in handling. Even if it was handled with polyethylene gloves, the molding material was not on the surface of the glove. It was in a state of many adhesions, and the injection amount was not sufficient with the same setting as other molding materials, and it seemed that the material leaked from the gap of the molding machine and there was a problem in meterability. The molded product could be filled in gaps of 30 μm and 100 μm, and the press fit of the obtained molded product was good. The molding material was generally poor in workability and could not be used for mass production.
The above results are shown in the table.
[0040]
[Table 1]

[0041]
From these Examples and Comparative Examples, it can be seen that when the Shore D hardness is 90 or less, a molded product having no problem with press fit can be obtained. Further, it can be seen that filling into a thin gap causes a filling failure when the penetration of the molding material is 30 or less.
In order to obtain a molded article excellent in press-fit property, the Shore D hardness needs to be 90 or less, and in order to obtain a good handling property with a filling property in a thin gap, the penetration of the molding material is 30 Must be ~ 150.
[0042]
【The invention's effect】
Since the molding material of the present invention is injection-molded by using BMC in a thin gap and has high dimensional accuracy and is flexible, it can be press-fitted into a gap made of metal or the like. Can be press-fitted and fixed easily.
[0043]
[Brief description of the drawings]
FIG. 1 is a view for explaining press-fitting fitting of a metal-containing molded product using a thermosetting molding material of the present invention into a metal gap.
FIG. 2 is a view for explaining the concept of metal inclusion injection molding using the thermosetting molding material of the present invention.

Claims (4)

A thermosetting molding material using an unsaturated polyester resin as a thermosetting resin, wherein 50 wt% or more of the total thermosetting resin on the basis of solid content is a glass having a double bond concentration of 2.0 mmol / g or less. It is an unsaturated polyester resin having a transition temperature of 70 ° C. or less, the volume content of the total amount of fibrous and particulate inorganic fillers is 50 vol% or less of the entire molding material, and the penetration of the molding material (JIS K 2235) is 30 to 150 (3 to 15 mm), Shore D (ASTM D676-55T) hardness of 90 or less can be formed thermosetting fitting molded article excellent in press fitting characteristics, injection molding for press fitting molded article use thermosetting molding material. Using unsaturated polyester resin as the thermosetting resin, the molding temperature 100 to 200 ° C., a heat-curable molding material capable thermoset molding by the molding cycle 5 minutes following injection molding, the total on a solids basis 50 wt% or more of the thermosetting resin is an unsaturated polyester resin having a double bond concentration of 2.0 mmol / g or less and a glass transition temperature of 70 ° C. or less, and contains a total volume of fibrous and particulate inorganic fillers. The rate is 50 vol% or less of the entire molding material, the penetration of the molding material (JIS K 2235) is 30 to 150 (3 to 15 mm), and the Shore D (ASTM D676-55T) hardness is 90 or less and excellent in press-fitting properties. press-fitting the synthetic form products for injection molding the thermosetting molding material, characterized in that to form a thermoset fitting synthetic molded product was. The thermosetting resin molding material for injection molding for press-fitting fitting products according to claim 1 or 2 , comprising a physical thickener made of thermoplastic resin particles. A press-fit fitting product formed by molding the thermosetting molding material according to any one of claims 1 to 3 .

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