JPH0967775A - Thermosetting resin composite material sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermosetting resin composite material sheet excellent in perspective property at high temperature. SOLUTION: This thermosetting resin composite material sheet is obtained by impregnating a flame retardant thermosetting acrylic ester resin composition into an inorganic bose material and curing the composition. In the sheet, a refractive index G at 20 deg.C of an inorganic fiber and refractive index R at 20 deg.C of the flame-retardant thermosetting acrylic ester resin composition after curing have a relationship of the following formula. G+0.015<=R<=G+0.040.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting resin composite material sheet, and more particularly to a thermosetting resin composite material sheet used as a material for a welding curtain in a welding or fusing work site.

[0002]

2. Description of the Related Art Conventionally, a plasticized vinyl chloride resin sheet has been widely used as a material for a welding curtain. However, even if the thermoplastic resin sheet such as the plasticized vinyl chloride resin sheet is flame-retardant, it is basically a flammable material, and when used in a welding curtain, it does not burn. In addition, there is a drawback that sparks such as sparks and spatters generated during welding or fusing work penetrate and holes are easily opened.

As a welding curtain material for removing the drawbacks of the thermoplastic resin sheet such as the plasticized vinyl chloride resin sheet, the present inventors have previously disclosed JP-A-5-12.
A welding curtain material disclosed in Japanese Patent No. 3869, which comprises a fiber-reinforced resin sheet obtained by impregnating a woven fabric or a nonwoven fabric made of an inorganic fiber having a light-transmitting property with a flame-retardant thermosetting resin composition and curing the same. The relationship between the refractive index A after curing of the flame-retardant thermosetting resin composition and the refractive index B of the above-mentioned inorganic fibers is expressed by the following formula B + 0.015 ≧ A ≧ B-0.
005 ... (1) is satisfied, and the parallel light transmittance of the fiber-reinforced resin sheet is 8 of the total light transmittance.
We have developed a welding curtain material that is 0% or more.

The welding curtain material disclosed in the above-mentioned Japanese Patent Laid-Open No. 5-123869 is not only transparent and capable of seeing through the inside from the outside, but also flame-retardant, such as welding, welding and fusing. Even if a spark such as a spark or spatter generated during the work hits the through hole, it was difficult to open the hole, which greatly contributed to the prevention of disasters and fires, but it also devitrified at high temperatures. Even if the phenomenon of devitrification at high temperature was used by knowing it, it could be used as a significant welding curtain material.
There has been a new demand for the development of a welding curtain material that allows the interior to be seen from the outside in a high-temperature environment near 100 ° C. or higher.

The inventors of the present invention have described the above-mentioned Japanese Patent Laid-Open No. 12386/1993.
The phenomenon of devitrification of the welding curtain material disclosed in Japanese Laid-Open Publication No. 9 was studied at high temperature, and there was a change in the refractive index of the material due to temperature change, and the refraction between the thermosetting resin composition cured product and the fiber-reinforced glass We have found that this occurs because of the different rate-temperature dependence. That is, at a high temperature exceeding 100 ° C., the change in the refractive index of the polymer substance such as the cured product of the thermosetting resin composition is considerably larger than the change in the refractive index of the inorganic substance such as fiber-reinforced glass. Therefore, it has been found that the difference in the refractive index between the two materials increases as the temperature rises, and finally the devitrification of the welding curtain material at high temperature is reached.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above facts, and an object thereof is to provide a thermosetting resin composite material sheet excellent in transparency at high temperature. To provide.

[0007]

The present invention relates to a thermosetting resin composite material sheet obtained by impregnating and curing an inorganic fiber base material with a flame-retardant thermosetting acrylic acid ester resin composition, which comprises the above-mentioned inorganic fibers. A thermosetting resin composite material sheet, characterized in that the refractive index G at 20 ° C. and the refractive index R at 20 ° C. of the flame-retardant thermosetting acrylic ester resin composition after curing have the following relationship: It is a summary. G + 0.015 ≦ R ≦ G + 0.040

The flame-retardant thermosetting acrylic acid ester resin composition is not particularly limited as long as it is a flame-retardant thermosetting acrylic acid ester resin composition, and examples thereof include aryl halides. Of acrylic acid ester derivative as a main component, containing a liquid cross-linking agent capable of dissolving the acrylic acid ester derivative and a phosphorus-containing monomer, and further containing a softening agent, a plasticizer, an ultraviolet absorber, an antistatic agent, a defoaming agent, if necessary. Examples of the composition include agents, internal mold release agents, wetting agents, coloring agents, and other flame retardants. The halogen element content of the flame-retardant thermosetting acrylic ester resin composition is about 15 to 50% by weight, and the phosphorus element content is about 1 to 10% by weight. Flame retardancy can be imparted without impairing the transparency of the cured product of the flammable thermosetting acrylic ester resin composition.

The above aryl halide acrylate derivative contains at least one of chlorine, bromine, and iodine.
Acrylic ester derivatives of aryl halides preferably contained in an amount of 20 to 50% by weight, for example, tetrabromobisphenol A-diacrylate, tetrabromobisphenol A-ethylene oxide adduct dimethacrylate, tribromophenyl acrylate, tribromophenyl. Methacrylate, trichlorophenyl methacrylate and their macromers are mentioned. These monomers and macromers may contain glycidyl ether in the molecule.

Examples of the liquid crosslinking agent include tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl acrylate, 2-hydroxyethyl acrylate and methoxy. Triethylene glycol (di) acrylate, isobornyl acrylate, dimethylaminoethyl acrylate, neopentyl glycol diacrylate,
Examples thereof include acrylic acid ester monomers containing 1 to 3 terminal vinyl groups such as pentaerythritol tri (meth) acrylate. The blending amount of the liquid cross-linking agent is preferably 20 to 80% by weight in the flame-retardant thermosetting acrylic ester resin composition.

Examples of the above-mentioned phosphorus-containing monomer include acrylic acid ester or ether such as mono (2-acryloyloxyethyl) acid phosphate, diphenyl-2- (meth) acryloyloxyethyl phosphate, and bis2-chloroethyl-vinyl phosphate. Examples thereof include acid ester derivatives. The blending amount of the above-mentioned phosphorus-containing monomer is preferably 10 to 40% by weight in the above flame-retardant thermosetting acrylic ester resin composition. If the blending amount is less than 10% by weight, sufficient flame retardancy cannot be obtained,
If it exceeds 40% by weight, the refractive index of the obtained flame-retardant thermosetting acrylic acid ester resin composition cured product becomes too large, and it becomes difficult to obtain transparency at high temperature.

The above-mentioned softening agent imparts flexibility to the thermosetting resin composite material sheet to be obtained, and when the thermosetting resin composite material sheet is used as a welding curtain, it has a good response to refraction at the time of opening and closing and the like. And to prevent alteration that impairs transparency, for example,
Polyfunctional oligomers such as urethane acrylate, epoxy acrylate, polyester acrylate, etc. may be mentioned. Further, the plasticizer is a compounding agent that exhibits the same action as the softening agent, but, for example, trisdichloropropylphosphate, trismonochloropropylphosphate,
Phosphate ester flame-retardant plasticizers such as trischloroethyl phosphate, trisbromophenyl phosphate, and triphenyl phosphate are preferably used.

The above-mentioned inorganic fiber base material is not particularly limited in its material and form as long as each inorganic fiber element can transmit visible light. For example, glass fiber is plain woven, twilled, or other various types. Woven fabrics, knits of various structures, sheet-like materials in which glass fibers are aligned in one direction, sheet-like materials in which glass fibers are randomly arranged and the intersections of glass fibers are bonded with a binder, glass fiber chopped strand mat And the like. As the above-mentioned inorganic fibers, in addition to glass fibers, transparent ceramic fibers having heat resistance that does not melt at a high temperature of about 1000 ° C. and having transparency, for example, manufactured from a ceramic material such as alumina can be used.

Further, as an example of the above-mentioned inorganic fiber base material, there is a glass cloth having a diameter of 3 to 15 μm and a woven structure of 21 to 80 × 21 to 80 plain weaves per plain weave. The lower limit numerical value of the diameter of the glass fiber and the number of glass fibers of the woven structure is mainly set from the mechanical strength of the inorganic fiber substrate or the mechanical strength of the thermosetting resin composite sheet obtained. , The upper limit value is set mainly from the appearance performance of the thermosetting resin composite material sheet obtained.

The method for producing the thermosetting resin composite material sheet of the present invention is not particularly limited.
The above flame-retardant thermosetting acrylic acid ester resin composition is impregnated and coated on the above-mentioned inorganic fiber base material, both surfaces thereof are coated with a polyethylene terephthalate resin film to form a laminate, and then the above-mentioned laminate is sandwiched by a pressing roll. Using a smoothing device such as, to shape into a sheet, degas the gas adhering to the inorganic fiber substrate, and then irradiate with ultraviolet rays to the flame-retardant thermosetting acrylic At the same time when the acid ester resin composition is cured, it is integrated with the inorganic fiber base material to form a thermosetting resin composite material sheet.

As in the above-mentioned method for producing a thermosetting resin composite material sheet, the curing of the flame-retardant thermosetting acrylic ester resin composition by irradiation of ultraviolet rays is extremely quick in the curing reaction and is relatively simple. It is economical because it can be produced using equipment, and also in terms of quality, curing of the flame-retardant thermosetting acrylic ester resin composition from the glass fiber surface constituting the inorganic fiber substrate to which ultraviolet rays reach Since it starts, the glass fiber and the flame-retardant thermosetting acrylic acid ester resin composition are homogeneously and firmly adhered to each other at the interface, and the discontinuity of both layers at the interface such as peeling of both layers and craze. Can be minimized.

Since the thermosetting resin composite material sheet of the present invention is constructed as described above, the refractive index G of the above inorganic fiber at 20 ° C. and the flame retardant thermosetting acrylic ester resin composition after curing. Refractive index R of the object at 20 ° C is G +
0.015 ≦ R ≦ G + 0.040 is satisfied, and the temperature dependence of the refractive index of the flame-retardant thermosetting acrylic acid ester resin composition after curing is the same as that of the inorganic fiber. Although it is much larger than the temperature dependency, the transparency of the flame-retardant thermosetting acrylate resin composition after curing approaches that of the inorganic fiber in a high temperature environment near 100 ° C. Shows that you can see through from the outside.

[0018]

EXAMPLES The present invention will be described in more detail below with reference to examples.

(Raw materials) 1. Acrylic ester derivatives of aryl halides:
Brominated bisphenol A diacrylate 2. Liquid cross-linking agent: Equivalent mixture of benzyl methacrylate and 3-methoxybutyl acrylate. Flame-retardant plasticizer: tris (dichloropropyl) phosphate 4. 4. Phosphorus-containing monomer: diphenyl-2-methacryloyloxyethyl phosphate 5. Softener: Urethane acrylate 6. Polymerization initiator: Phenyl 2-hydroxy-2-propyl ketone 7. Inorganic fiber base material-1: Refractive index 1.55 at 20 ° C
6 glass fibers (diameter 10 μm), number of implants 50 ×
50, plain woven glass cloth having a thickness of 0.1 mm 8. Inorganic fiber base material-2: refractive index 1.54 at 20 ° C.
1 glass fiber (diameter 10 μm), number of shots 50 ×
50, plain woven glass cloth having a thickness of 0.1 mm 9. Inorganic fiber base material-3: Refractive index 1.52 at 20 ° C
3 glass fibers (diameter 10 μm), number of implants 50 ×
50, plain woven glass cloth with a thickness of 0.1 mm

Example 1 A base material made of an inorganic fiber capable of transmitting visible light has a refractive index of 1.52 at 20 ° C.
As shown in Table 1, an acrylic acid ester derivative of an aryl halide was added to a plain weave glass cloth (inorganic fiber base material-3) made of glass fiber No. 3 (diameter 10 μm) having a number of 50 × 50 and a thickness of 0.1 mm. Flame-retardant thermosetting acrylic ester consisting of 100 parts by weight, liquid crosslinking agent 30 parts by weight, flame retardant plasticizer 20 parts by weight, phosphorus-containing monomer 20 parts by weight, softener 20 parts by weight and polymerization initiator 1 part by weight. The resin composition is impregnated and cured for 1 hour in a 60 ° C. oven, and then placed on a polyethylene terephthalate film having a thickness of 125 μm, and the inorganic fiber substrate is the flame retardant thermosetting acrylic ester resin composition. The above-mentioned flame-retardant thermosetting acrylic ester resin composition is further applied so as to be buried in the product, and the same polyethylene terephthalate film as the above-mentioned polyethylene terephthalate film A rate film is laminated on the flame-retardant thermosetting acrylic acid ester resin composition-coated surface, sandwiched, and further defoamed using a roller, and then UV rays of 80 W / cm are applied by an UV irradiation device. Thirty
Irradiation for 2 seconds produced a thermosetting resin composite material sheet having a thickness of 0.24 mm and a volume ratio of glass cloth layer: flame-retardant thermosetting acrylic ester resin composition layer = 2: 3.

(Example 2), (Comparative Examples 1 to 4) Using the flame-retardant thermosetting acrylic ester resin composition and inorganic fiber base material shown in Table 1, heat curing was carried out in the same manner as in Example 1. A resinous resin composite sheet was produced.

In order to evaluate the performance of the thermosetting resin composite material sheets obtained in the above Examples and Comparative Examples, the refractive index of the glass fiber used and the cured flame-retardant thermosetting acrylic ester resin composition The refractive index, the temperature of devitrification by heating, the temperature of becoming transparent by heating, and the flame retardant performance were tested by the following methods. The test results are also shown in Table 1.

(Evaluation method) 1. Refractive index of glass fiber: Measured by a solution method according to JIS K0062. The standard solution used in the test and its refractive index (in parentheses) are dimethyl phthalate (1.51
3), 2-propanol (1.376), and butyl acetate (1.392). 2. Refractive Index of Cured Flame-Retardant Thermosetting Acrylic Ester Resin Composition: Measured using an Appe's refractometer.

3. Temperature at which devitrification or transparency is caused by heating: The obtained thermosetting resin composite material sheet is put in a gear oven and the temperature is raised in units of 1 ° C., and 5 cm drawn at a position 15 cm behind the test sample. The devitrification temperature was defined as the temperature at which a character with a size of × 5 cm could not be read through, and the temperature at which the character could be read through through was measured as the clearing temperature.

4. Flame-retardant performance: Difficulty of thermosetting resin composite material sheet obtained by performing Class B test (steel plate thickness 4.4 mm) and Class C test (steel plate thickness 3.2 mm) according to JIS A 1323 The flame performance was evaluated. The evaluation is indicated by ◯ indicating that each of the above test standards was cleared, and x indicating that the standard could not be cleared.

[0026]

[Table 1]

[0027]

The thermosetting resin composite sheet of the present invention is
Since it is configured as described above, it exhibits transparency in a high temperature environment and allows the inside (from inside to outside) to be seen from the outside. In addition, when used for welding curtains, it is difficult to open holes due to burning, sparks such as sparks or spatters generated during welding or fusing work, and mechanical strength and optical properties may be improved even by repeated refraction due to use. We provide a safe and secure welding curtain that does not change easily.

Claims (1)

[Claims] 1. A thermosetting resin composite sheet obtained by impregnating and curing a flame-retardant thermosetting acrylic acid ester resin composition in an inorganic fiber base material, wherein the inorganic fiber has a refractive index G at 20 ° C. and curing. A thermosetting resin composite material sheet, characterized in that the refractive index R at 20 ° C. of the flame-retardant thermosetting acrylic acid ester resin composition described later has the following relationship. G + 0.015 ≦ R ≦ G + 0.040