JP2005343112A - Epoxy resin molded article by pultrusion molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an epoxy resin molded article by pultrusion molding which has high strength, is lightweight, and does not damage electronic components. <P>SOLUTION: The epoxy resin molded article by pultrusion molding is provided, which, the one consisting of an epoxy resin composition and a carbon fiber that is a reinforcing fiber, contains 50-80 mass% of the carbon fiber and has an insulation layer provided on its surface, which has higher strength and is lighter compared with heretofore used materials such as aluminum and stainless steel, which does not damage electronic components by the electric running of static electricity, etc., since the surface is provided with the electrical insulation layer, and which is suitable for a member of easily handleable containers, racks and the like. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an epoxy resin pultruded product that is suitable for housing and transporting electronic components and is manufactured by a pultrusion molding method reinforced with carbon fibers.

  Containers, racks, etc. for storing and transporting electronic components must be strong enough to withstand the weight of electronic components and have basic performance such as excellent dust resistance. Until now, members formed of stainless steel, aluminum or the like have been used.

  However, in recent years, as the mass production of electronic components has progressed, the size of containers has also increased, and problems have arisen with the materials used so far. For example, when stainless steel is used, the weight increases due to the increase in size, making it difficult to carry and move, and the workability has deteriorated. In addition, when aluminum is used, the weight is light and workability is good even with an increase in size, but there are cases where it cannot withstand the weight of electronic components and cannot be stably housed due to its strength. there were.

  Under such circumstances, a material that is strong and can be reduced in weight has been studied, and the present inventor is lightweight and can stably store electronic components without reducing workability. Focusing on fiber reinforced plastic (FRP) whose strength is increased by fibers as a material having the strength that can be made, it has been studied to replace it.

Since fiber reinforced plastic is excellent in strength and heat resistance, and a molded product by pultrusion has good productivity and moldability (see, for example, Patent Document 1), it is practical when a container is enlarged. Carbon fiber is considered to be particularly suitable when it is excellent in weight and light weight is taken into consideration.
Japanese Patent Laid-Open No. 5-117212

  Such a pultruded product has reached the stage of practical use sufficiently because it is excellent in strength and light, but because it uses carbon fiber to increase the strength, when trying to accommodate electronic parts, An electronic component may come into contact with the surface of the container or the like, energize it and damage an expensive electronic component, making it unusable.

  Therefore, an object of the present invention is to provide a pultruded product that is strong, lightweight, and does not damage electronic components in order to eliminate such problems.

  As a result of diligent research to solve the above problems, the present inventor has provided an electric insulating layer on the surface without deteriorating static electricity due to the conductivity of the pultruded product using carbon fiber and reducing the weight. The present invention has been completed by finding a pultruded product that can prevent energization due to the occurrence of sparks and the like.

  That is, the epoxy resin pultruded product of the present invention is a pultruded product manufactured by impregnating an epoxy resin composition with carbon fiber, and contains 50 to 80% by mass of carbon fiber, and is insulated from the surface of the molded product. It is characterized by having a layer.

  According to the epoxy resin pultruded product of the present invention, it is a container, rack, etc. used for storage and transportation of electronic components, and has strength compared to those made of materials such as aluminum and stainless steel used so far. It has a property of being high and lightweight, and further, an electric insulating layer is provided on the surface thereof, so that an electronic component is not damaged by energization such as static electricity, and a container that is easy to handle, A rack or the like can be provided.

  Hereinafter, the present invention will be described in detail.

  The epoxy resin composition used in the present invention can contain an epoxy resin and a curing agent as essential components, and other components can be added as appropriate.

  The epoxy resin, which is an essential component, should be widely used without being limited by the molecular structure, molecular weight, etc., as long as it has two or more epoxy groups in one molecule and can be used for pultrusion molding. Can do. Among these, an epoxy resin containing no halogen atom is preferable from the viewpoint of environmental conservation.

  Examples of this epoxy resin include epoxy resins having bisphenol type, novolak type and biphenyl type aromatic groups, epoxy resins in which polycarboxylic acids are glycidyl etherified, and alicyclic epoxy resins in which epoxy groups are condensed to cyclohexane derivatives. Among them, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin are particularly preferable. Moreover, these epoxy resins can be used individually or in mixture of 2 or more types.

  Examples of the bisphenol A type epoxy resin include Epicoat 828 (manufactured by Yuka Shell Epoxy), Araldite AER260 (manufactured by Ciba Geigy), and examples of the bisphenol F type epoxy resin include Epicoat 807 (manufactured by Yuka Shell).

  A trifunctional or higher functional epoxy resin may have a particularly poor viscosity stability of a resin composition containing a curing agent, which may make it difficult to implement the present invention.

  The viscosity of an epoxy resin composition should just be a viscosity suitable for pultrusion molding, and it is preferable that it is the range of 0.3-0.5 Pa.s at 25 degreeC. Viscosity can be adjusted by adding a small amount of a reactive diluent such as phenyl glycidyl ether or butanediol diglycidyl ether (DY-026 manufactured by Ciba Geigy) as appropriate to an epoxy resin having as low a viscosity as possible. Technology can be used.

  In addition, examples of the curing agent to be included in the epoxy resin composition include acid anhydrides and bases. However, the curing agent used at this time is a long pot life during the curing reaction of the resin composition. It is calculated | required that it is excellent in a moldability, and it is preferable that it is an acid anhydride. Furthermore, the resin composition satisfies the characteristics such as a small shrinkage ratio at the time of curing, high dimensional accuracy, high heat resistance, a cured product having excellent mechanical and electrical properties, and low irritation. It is also required.

  Examples of the acid anhydride used as the curing agent include alicyclic acid anhydrides, chain aliphatic acid anhydrides, aromatic acid anhydrides, and the like. For example, phthalic anhydride, maleic anhydride, hexahydrophthalic anhydride Examples include acid, pyromellitic acid anhydride, trimellitic acid anhydride, trimellitic acid glycol, methyl nadic acid anhydride, dodecyl succinic acid anhydride, and the like. Among these, an alicyclic acid anhydride is preferable because of its easy handling.

  Furthermore, if necessary, a curing accelerator may be mixed in the epoxy resin composition. Examples of the curing accelerator include amines such as benzyldimethylamine, triethylamine, dimethylaminomethylphenol, trisdimethylaminomethylphenol, and the like. Examples include imidazoles such as 2-ethyl-4-methylimidazole and 1-benzyl-2-methylimidazole, and these may be used alone or in admixture of two or more.

  This epoxy resin composition is blended with inorganic fillers such as aluminum hydroxide, gypsum and talc, flame retardants, UV degradation inhibitors, pigments, low shrinkage agents, etc., as long as they do not impair the properties of pultruded products. can do.

  The carbon fiber used in the present invention has an effect of increasing the strength of a cured product, particularly tensile strength, flexibility, impact resistance strength, etc., and can be used in the form of roving, mat, cloth, etc. Roving is preferable from the viewpoint of ease of molding and cost.

  Moreover, as this carbon fiber, what converged 6000-48000 carbon fiber filaments with a diameter of 5-15 micrometers can be used, for example, and 24,000-48000 carbon fiber filaments with a diameter of 6.7-7.0 micrometers converged. It is preferable that

  This carbon fiber contains 50-80 mass% of a pultruded product, and it is preferable that it is 60-75 mass%. If it is less than 50% by mass, the strength becomes insufficient, and if it exceeds 80% by mass, the content of the epoxy resin decreases, and furthermore, the pulling resistance increases, so that molding becomes difficult.

  The insulating layer used in the present invention prevents the current from flowing from the conductive carbon fiber to the electronic component by preventing the carbon fiber contained in the pultruded product from coming into contact with the electronic component.

  The insulating layer can be formed from a known insulating material, and is preferably formed from a polymer material such as a natural polymer material, a synthetic polymer material, or a polymer material containing an inorganic insulating material. In addition, as the polymer material, either a thermoplastic resin or a thermosetting resin can be used.

  Examples of the polymer material include epoxy resins, unsaturated polyester resins, urethane resins, phenol resins, melamine resins, urea resins, allyl resins, silicone resins, polyimide resins, acrylic resins, and the like. It is preferably an unsaturated polyester resin, urethane resin, or acrylic resin.

  The polymer material used at this time can form an insulating layer by application to the surface of an epoxy resin pultruded molded product, and is liquid at room temperature. A resin capable of forming a layer is preferable. For example, examples of the epoxy resin include a room temperature drying type solvent type epoxy resin, a heat drying type epoxy liquid resin, and the like, which can be appropriately selected depending on the workability.

  The thickness of the insulating layer may be in the range of 0.001 to 0.01 mm, and if it is less than 0.001 mm, sufficient insulation cannot be obtained, and if it exceeds 0.01 mm, the insulating layer is thickened. Only the cost becomes high.

  In addition, this insulating layer may be formed so as to cover the entire epoxy resin pultruded product, or may be formed only on a part of the surface, but at least on the contact surface of the electronic component. is required. In view of cost, it is preferable to form an insulating layer only on the contact surface of the electronic component.

  Next, the manufacturing method of the epoxy resin pultruded molded product of the present invention will be described.

  In the present invention, a conventionally known pultrusion molding method using an epoxy resin, for example, pultrusion molding, is performed in parallel with the pultrusion molding or heat-cured after the pultrusion molding to obtain a pultrusion molded product, and the obtained pultrusion molding is further performed. An epoxy resin pultruded product can be formed by applying an electrically insulating resin to the surface of the product to form an insulating film.

  FIG. 1 is a side sectional view of a pultrusion molding apparatus 1 showing an example of a pultrusion molding method. A carbon fiber roving 2 is continuously passed through an impregnation tank 3 containing a mixture of an epoxy resin and a curing agent. The carbon fiber to which is attached is passed through the heating mold 4 and a preforming is performed in which the carbon fiber is cured to the extent that it has shape retaining property immediately after leaving the mold. Thereafter, the preformed resin is immediately passed through the post-curing device 5 to be finally cured, and the molded product 7 having a constant cross section can be continuously molded while being pulled by the pulling machine 6.

  The molded article 7 continuously drawn and molded is cut to an appropriate length by a cutting device 8 perpendicular to the axial direction, and a thermosetting resin serving as an insulating layer is applied to the surface of the cut molded article and cured. Thus, a pultruded product finally used can be obtained.

  The cross-sectional shape of the cut surface of the pultruded product obtained at this time may be any shape, for example, a circle, a triangle, a square, a U shape, a shape obtained by deforming the U shape as shown in FIG. This can be made into an arbitrary shape, and is determined by appropriately selecting the shape of the mold of the heating mold 4.

  This pultruded product can be made into a container, a rack, or the like by, for example, arranging a plurality of them in parallel and connecting / fixing one end or both ends thereof to a support to form an electronic component housing portion. . When an electronic component is accommodated, an insulating layer made of an electrically insulating resin is formed at the contact portion between the pultruded product and the electronic component, so that the electronic component is not affected by the carbon fiber of the pultruded product. There is no worry about damage.

  The step of forming the insulating layer of the pultruded product may be performed either after preforming or after curing. For example, the insulating layer is insulated after preforming using a thermosetting resin. When the layer is formed, the pultruded product and the insulating layer can be simultaneously cured and formed during post-curing.

  Moreover, formation of this insulating layer can be achieved by coating the surface of the resin that has been preformed or post-cured by using a coating method such as brush, roller, spray, or roll. This insulating layer may be formed so as to cover the entire epoxy resin pultruded product, or may be formed only on a part of the surface, but it must be formed at least on the contact surface of the electronic component. It is.

  EXAMPLES Next, although an Example demonstrates this invention, this invention is not limited to these Examples.

(Example 1)
100 parts by mass of bisphenol A type epoxy resin (Dainippon Ink Industries, trade name: Epicron 850S), 80 parts by mass of alicyclic acid anhydride (Dainippon Ink Industries, trade name: B-570), Imidazole-based curing accelerator (manufactured by Shikoku Kasei Co., Ltd., trade name: 2E4MZ) Prepare a liquid epoxy resin mixed with 2.5 parts by mass and 2.0 parts by mass of carnauba wax in a container for impregnation, and carbon fiber (Toho Tenax) Made by Co., Ltd., trade name: Besfight HTA-24K) is impregnated in this liquid epoxy resin, and the mold (length: 80 cm) at 170 ° C. is pulled out at a rate of 30 cm / min. A round bar having a diameter of 10 mm was obtained.

  Two-component mixed room temperature drying epoxy resin (trade name: TEB9502 and Kyocera Chemical Co., Ltd., trade name: TEB9503, 1: 1 mixture as an insulating resin for surface treatment on the obtained round bar. ) Was applied and cured with a spray device to form a 0.3 mm insulating layer, and an epoxy resin pultruded product containing 75% by mass of carbon fiber was produced. The properties of this molded product are shown in Table 1.

[Specific gravity]: Using a test piece having a weight of 4 g, the specific gravity was measured in accordance with JIS K 6911.
[Bending strength]: Measured according to JIS K 6911 using a test piece of length 120 × diameter 10 mm.
[Elastic modulus]: Measured according to JIS K 6911.
[Insulation resistance]: Measured according to JIS K 6911.

(Example 2)
The same liquid epoxy resin as in Example 1 was prepared, carbon fiber (manufactured by Toho Tenax Co., Ltd., trade name: Besfight HTA-24K) was impregnated in this liquid epoxy resin, and a 170 ° C. mold (length: 80 cm) The inside was pulled out at a speed of 30 cm / min to obtain a modified pultruded product having the cross-sectional shape shown in FIG.

  A two-component mixed room temperature drying epoxy resin (manufactured by Kyocera Chemical Co., Ltd., trade name: TEB9502 and Kyocera Chemical Co., Ltd., trade name: TEB9503) is used as an insulating resin for surface treatment on the obtained pultruded molded product. 1 mixture) was applied and cured by a spray device to form a 0.3 mm insulating layer, and a deformed epoxy resin pultruded product containing 75% by mass of carbon fiber was produced.

When the insulation resistance of the surface of this pultruded product was measured in the same manner as in Example 1, it showed an electrical insulation of 1 × 10 ¹¹ Ω or more.

  Further, when a 50 kg load was applied to the pultruded product, it was found that the pultruded product was not damaged, deformed, etc., and had sufficient strength for transportation of electronic components.

  On the other hand, a molded product of the same shape was obtained with stainless steel, but when trying to make a product with the same weight as the pultruded molded product produced in Example 2, the plate thickness was too thin, about 0.4 mm, It was confirmed that even if it was difficult to mold properly or could be molded, it could not withstand a load of 50 kg and deformed.

  From the above results, the epoxy resin pultruded product of the present invention is lightweight and has sufficient strength, and does not have an electrical effect on the contents. It is suitable for etc.

It is a sectional side view of the manufacturing apparatus of a pultruded product. It is the figure which showed an example of the cross-sectional shape of a pultruded product.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Pull forming apparatus, 2 ... Carbon fiber roving, 3 ... Impregnation tank, 4 ... Heating die, 5 ... Post-curing apparatus, 6 ... Pulling machine, 7 ... Molded product, 8 ... Cutting apparatus

Claims (4)

In an epoxy resin pultruded molded product composed of an epoxy resin composition and carbon fibers that are reinforcing fibers
An epoxy resin pultruded molded product comprising 50 to 80% by mass of the carbon fiber and having an insulating layer on the molded product surface.   The epoxy resin pultruded product according to claim 1, wherein the insulating layer is formed of at least one insulating resin selected from an epoxy resin, a urethane resin, an unsaturated polyester resin, and an acrylic resin.   The epoxy resin pultruded molded product according to claim 1 or 2, wherein the epoxy resin of the epoxy resin composition is a bisphenol A type epoxy resin.   The epoxy resin pultruded product according to any one of claims 1 to 3, wherein the carbon fiber is contained in an amount of 60 to 75 mass%.

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