JP2003105111A - Manufacturing method of unsaturated polyester resin- molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an SMC-molded product having high strength as well as the inexpensive SMC-molded product by including a patterning material only on the surface layer. SOLUTION: In a method for manufacturing an unsaturated polyester resin- molded product molded by laminating plural sheet molding compounds in which an unsaturated polyester resin composition containing an unsaturated polyester resin, a polymerizable monomer, a low shrink material, a curing agent and a thickener is impregnated into a fiber base material, the method for manufacturing the unsaturated polyester resin-molded product is made to contain a pattern material of the sheet molding compound only corresponding to the surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melting chamber equipment such as a ladle tank, a washing pan, and a panel wall of a lahar room, a panel assembly type water storage tank, and a septic tank by molding using a sheet molding compound (hereinafter referred to as SMC). , A method for producing an unsaturated polyester resin molded product such as a kitchen countertop.

[0002]

2. Description of the Related Art SMC is an unsaturated polyester prepared by diluting a vinyl monomer with additives such as a low-shrinking agent, a curing agent, a polymerization inhibitor, a filler, a thickening agent, a template, and coloring. It is a molding material in which glass fiber is impregnated in a paste mixed with a chemical agent and the like to form a sheet, both sides of which are covered with a carrier film and aged to be semi-solidified. SMC is placed in a mold and pressure-heated to be manufactured as an SMC molded product such as a tank, a panel assembly type water storage tank, a septic tank, and a kitchen countertop.

The SM heat-molded as described above
C molded products are excellent in durability, water resistance, mechanical strength, gloss of the surface of the molded products, and have a large degree of freedom in shape, and are excellent in design. }, Panel assembly type water storage tank, septic tank, etc. Among these, the method of press-molding the counter top of the kitchen under pressure is BMC (Bu
lk Molding Compound). Compared to SMC after molding, this BMC is used for kitchen countertops, etc. where human hands can touch it, because the fibers are not exposed at the edges, but it is necessary to increase the pressure because it is a lump as a material. However, the SMC material has been reviewed due to the improvement of the mold as a countermeasure against the edge.
In the case of this SMC, a plurality of SMCs were laminated in a thick molded product such as a kitchen countertop.
Each of the plurality of SMCs is manufactured by containing and crushing a pattern material. The respective SMCs were laminated and processed as a molded product.

[0004]

The specification of the kitchen countertop is that the desired pattern appears only on the surface layer, and the pattern material itself is expensive. Therefore, if a plurality of layers are laminated and molded, it becomes an expensive product. In addition, the strength of the molded product may be reduced by including the pattern material in the portion other than the surface layer.

The present invention has been made in view of the above problems, and an object thereof is to provide an SMC molded article having high strength, and at the same time, an inexpensive SM by containing a pattern material only in the surface layer.
The purpose is to provide a C molded product.

[0006]

The present invention relates to the following. (1) A plurality of sheet molding compounds obtained by impregnating a fiber base material with an unsaturated polyester resin composition containing an unsaturated polyester resin, a polymerizable monomer, a low shrinkage material, a curing agent and a thickener are laminated. A method for producing an unsaturated polyester resin molded article by molding, wherein the pattern material is contained only in the sheet molding compound corresponding to the surface. (2) The method for producing an unsaturated polyester resin molded article according to item (1), wherein the pattern material is a pulverized product of an unsaturated polyester resin or an inorganic material. (3) The unsaturated polyester according to item (1) or (2), wherein the content of the patterning material in the sheet molding compound corresponding to the surface is 10 to 40% of the whole unsaturated polyester resin composition used. Manufacturing method of resin molded product.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION When an unsaturated polyester resin molded product is manufactured by molding a sheet molding compound, generally, several sheet molding compounds are laminated and arranged in a mold, and molding is performed. In the present invention, only the surface side of the molded product, that is, the product surface, is used as the remaining sheet molding compound for laminating the above-mentioned sheet molding compound, except that the pattern material is removed from the above composition.

The sheet molding compound (SMC) according to the present invention comprises an unsaturated polyester resin composition containing an unsaturated polyester resin, a polymerizable monomer, a low-shrinking agent, a curing agent and a thickening agent as a fiber reinforcing material. The fiber-reinforced molding material is impregnated and is formed into a sheet. In the present invention, as the unsaturated polyester resin composition, a material further containing a pattern material is used.

The unsaturated polyester resin in the present invention is obtained by reacting a polybasic acid component containing α, β-unsaturated polybasic acid or its anhydride as an essential component with a polyhydric alcohol. In the present invention, as the α, β-unsaturated polybasic acid or its anhydride, which is a raw material for synthesizing the unsaturated polyester resin, for example, α, β monounsaturated dibasic acid or its anhydride, for example, maleic acid, Examples thereof include fumaric acid, itaconic acid, citraconic acid, maleic anhydride, and their anhydrides. You may use 2 or more types together. As the polybasic acid component, in order to adjust the concentration of unsaturated groups, and to impart properties such as susceptibility and heat resistance, in addition to α, β-unsaturated polybasic acid or its anhydride, Iiwa It is preferable to use a polybasic acid or its anhydride together. At this time, α, β-
The unsaturated polybasic acid or its anhydride is preferably 40 mol% or more of the polybasic acid component. α, β-
When the unsaturated polybasic acid or its anhydride is less than 40 mol%, the strength of the obtained molded article tends to gradually decrease. From this, it is more preferable that the α, β monounsaturated polybasic acid or its anhydride is 45 to 80 mol%.
It is particularly preferably from 0 to 70 mol%.

Examples of the saturated polybasic acid or its anhydride to be used in combination include fuculic acid, fucric anhydride, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, tetrahydrophthalic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, Hexahydrophthalic acid, hexahydrophthalic anhydride, glutaric acid, adipic acid, sebacic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, dimer ←
Examples thereof include acids, succinic acid, azelaic acid, and rosin-maleic acid adducts. These may be used in combination of two or more.

As the polyhydric alcohol which is another synthetic raw material of the unsaturated polyester resin, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanedio} l, 1,
6-hexanediol, neopentyl glycol, 1,
Examples thereof include dihydric alcohols such as 4-cyclohexanediol and hydrogenated pispheno} l A, trihydric alcohols such as glycerin and trimethylo} lpropane, and tetrahydric alcohols such as pentaerythritol. These may be used in combination of two or more.

The polybasic acid component and the polyhydric alcohol are preferably used in an equivalent ratio of 1 to 1.3 when the polybasic acid component is 1.
It is more preferable to use in the range of 1.05. When the amount of polyvalent alcohol is small, the molecular weight of the unsaturated polyester resin obtained tends to be small, and when it is large, the acid value is small and the progress of thickening by the thickener tends to be slow.

The unsaturated polyester resin can be produced by a conventionally known method. For example,
A polybasic acid component and a polyhydric alcohol component are subjected to a condensation reaction,
The process proceeds while removing the condensation water generated when both components react with each other. Removal of the condensed water to the outside of the system is preferably carried out by natural distillation or reduced pressure distillation by passing an inert gas. A solvent such as toluene or xylene can be added to the system as an azeotropic component in order to promote the distillation of condensed water. The progress of the reaction can be generally known by measuring the amount of distillate produced by the reaction, quantifying the terminal functional group, measuring the viscosity of the reaction system, and the like. The reaction temperature is preferably 150 ° C. or higher, and it is preferable to carry out the reaction while aerating an inert gas such as nitrogen or carbon dioxide in order to prevent side reactions due to oxidation. , Glass, stainless steel, etc. are selected, stirring device is selected, stirring device, fractionating device for preventing distillation of alcohol component due to azeotropic distillation of water and alcohol component, heating device for raising temperature of reaction system It is preferable to use a reaction device equipped with a temperature control device for this heating device, a device for blowing in an inert gas such as nitrogen, and the like.

The number average molecular weight of the unsaturated polyester is 25.
It is preferably from 00 to 4500. Molecular weight is 250
When it is lower than 0, the viscosity does not increase even if an appropriate amount of the thickener is added, and when it is made into a resin composition, it is soft and the workability is deteriorated. When the molecular weight is larger than 4,500, the viscosity is high and the glass fiber becomes poor in embrittlement and the surface gloss is lowered when molded.

As the polymerizable monomer used in the present invention, for example, styrene derivatives such as styrene, chlorostyrene, divinylbenzene, evening sialyptyl styrene and styrene bromide, methyl methacrylate, ethyl methacrylate, acryl. Methacrylic acid or acrylic acid alkyl ester such as ethyl acrylate and butyl acrylate, methacrylic acid or acrylic acid hydroxyalkyl ester such as β-hydroxyethyl methacrylate and β-hydroxyethyl acrylate, diallyl phthalate, acrylamide, phenylmaleimide And so on. It is also possible to use a polyfunctional methacrylic acid or acrylic acid ester such as ethylene glycol dimethacrylate, neopentyl glycol dimethacrylate or trimethylethyltrimethacrylate.

An unsaturated polyester resin composition is prepared by blending an unsaturated polyester resin and a polymerizable monomer, and optionally adding a polymerization inhibitor and the like. The mixing ratio of the unsaturated polyester resin and the polymerizable monomer at this time is 25 to 80 parts by mass of the unsaturated polyester resin and 75 to 100 parts by mass of the polymerizable monomer, when the total amount of the two is 100 parts by mass. It is preferably 20 parts by mass. When the amount is less than 25 parts by mass, the viscosity of the unsaturated polyester resin composition is too low to be easily applied in a sheet form, and it is difficult to uniformly mix it with other components due to sedimentation and the like. Even when the material is molded, the curing shrinkage rate is large and the molded product may be cracked or cracked. 80 unsaturated polyester resin
If the amount is more than parts by mass, the viscosity may be too high and it may be difficult to apply or mix with other components. From this, it is more preferable that the unsaturated polyester resin is 40 to 65 parts by mass and the polymerizable monomer is 60 to 35 parts by mass. Examples of the polymerization inhibitor include P-penzoquinone, naphthoquinone, toluquinone, hydroquinone, mono-t-putylhydroquinone, diptylhydroxytoluene and the like. The polymerization inhibitor is preferably used in an amount of 0.5% by weight or less based on the total amount of the unsaturated polyester resin and the polymerizable monomer. When the curing agent is blended, it is preferably contained in an amount of 0.05% by weight or more for storage stability.

As the low-shrinkage agent used in the present invention, thermoplastic resins such as polymethylmethacrylate, polystyrene, polycaprolactone, polyvinyl acetate, polyethylene and butadiene rubber are used. The amount used is determined in consideration of the shrinkage rate, surface smoothness, and surface gloss of the molded product, and is not particularly limited. The low-shrinking agent is preferably used in the range of 20 to 50% by weight based on the total amount of the unsaturated polyester resin and the polymerizable monomer.

As the curing agent used in the present invention, ketone peroxides, peroxydicarbonates, hydroperoxides, disilver oxides,
Peroxyketals, dialkylpara ← oxides,
Examples include peroxyesters and alkyl bar esters. The amount of the curing agent affects not only the molding cycle but also the storability of the material, color unevenness, and the like, and thus is determined depending on each. From the standpoint of the storability of the material and the molding cycle, it is preferably 0.5 to 5% by weight, more preferably 1 to 3% by weight, based on the total amount of the unsaturated polyester resin and the polymerizable monomer.

As the thickener, magnesium oxide, magnesium hydroxide, potassium oxide, potassium hydroxide or the like is used, but magnesium oxide is generally used. The amount of the thickener is determined according to the workability of the molding material, but is preferably 0.5 to 5% by weight, and more preferably the total amount of the unsaturated polyester resin and the polymerizable monomer. It is 0.7 to 2% by weight. If the amount of the thickener is too small, the viscosity of the resin composition may not increase. On the other hand, if the amount of the thickener is too large, the viscosity may increase too much to be controlled.

Inorganic fillers, mold release agents, stabilizers, colorants and the like are further added to the above unsaturated polyester resin composition.

Examples of the inorganic filler include silica sand, calcium carbonate, talc, clay, etc. 0 The amount of the inorganic filler is 100 parts by mass of a mixture of an unsaturated polyester resin, a polymerizable monomer and a low-shrinking agent. For 100 to 200
It is preferably part by mass.

As the release agent, zinc stearate, calcium stearate, etc. are used. The amount of the releasing agent is preferably 1 to 10% by weight, and more preferably 2 to 10% by weight based on the total amount of the unsaturated polyester resin and the polymerizable monomer.
It is 4% by weight. If the amount of the release agent is too small, the molded product may stick to the mold if it is less than 1 part by mass, and it may be difficult to remove the molded product, and the molded product may be cracked. Further, if the amount of the release agent is too much, the strength of the molded product tends to be lowered.

The pattern material includes organic substances and inorganic substances. The organic substances include polyester resin and other ABS resins, crushed products of resins such as epoxy, melamine, and phenol, and non-woven fabrics on which pattern materials are dispersed, and the inorganic substances include mica, There are crushed stones such as glass, quartz, and marble. The size of the pattern material is preferably such that 4 mesh passes and 100 mesh does not pass. The amount of the pattern material is preferably 10 to 40% by weight, more preferably 20 to 30% by weight, based on the total amount. If the amount of the patterning material is too small, the desired pattern will not appear, and if it is too large, the strength of the molded product will decrease.

As the fiber reinforcing material, glass fiber, synthetic fiber and natural fiber are used. 0 The content of these glass fiber, synthetic fiber and natural fiber in SMC is preferably 1 to 40% by mass. However, the reinforcing effect is not sufficient, and the strength of the obtained SMC molded crystal is insufficient. Also, if it exceeds 40 mass, the thinness of the unsaturated polyester resin composition will decrease, defects such as fiber grains, blisters, cracks and pinholes will occur in the molded product, impairing the appearance of the product and lowering the strength. The glass fiber, synthetic fiber and natural fiber to be used may be woven cloth, cloth, chopped short fiber, or the like. When the product is manufactured), the resin has a better fluidity than the cloth, and the uniform dispersibility of the fiber and the resin embrittlement are better than the chopped short fiber. The length of glass fiber, synthetic fiber and natural fiber constituting the glass fiber, synthetic fiber and natural fiber base material is 3 to 15
0 mm is suitable. If the fiber length is less than 3 mm, the reinforcing effect is insufficient and the strength of the molded product is insufficient, and if it exceeds 150 mm, the flowability of the resin at the time of molding is poor, the appearance of the molded product is impaired, and the filling property into ribs and bosses is also Bad, use of molded articles,
This is because the shape is limited. Further, the fiber diameter of the glass fiber, the synthetic fiber, and the glass fiber constituting the natural fiber base material, the synthetic fiber, and the natural fiber is preferably 0.01 to 5 mm. This is because when the thickness exceeds 5 mm, the thinness of the resin is poor, the strength of the molded product is insufficient, the appearance is impaired, and the use and shape of the molded product are limited. In particular, inexpensive natural fibers do not have a constant fiber diameter, and the substrate diameter may exceed 5 mm even when twisted under the same conditions. Therefore, by mixing or blending glass fibers and synthetic fibers with a constant fiber diameter, The diameter of the base material, which is the upper limit of the quality control of the base material, is set to 5 mm. As the synthetic fiber, polyester fiber, cellulose fiber, nylon fiber, aramid fiber or the like can be used, but polyester fiber is preferable because it has excellent adhesion to the unsaturated polyester resin.

The SMC can be manufactured by using an ordinary SMC manufacturing apparatus. The unsaturated polyester resin composition is applied to the carrier films arranged above and below so as to have a uniform thickness, and the fiber reinforcing material of a predetermined size unwound from the unwinding device is arranged above and below. The carrier film is sandwiched between unsaturated polyester resin compositions, then the whole is passed between impregnating rolls, pressure is applied to impregnate the unsaturated polyester resin composition with the fiber reinforcement, and then the rolls are wound. Fold it in a fold. After that, aging or the like is performed if necessary. When a thickener is added, it is preferable to heat it at a temperature of room temperature to 60 ° C. for aging. A polyethylene film, a polypropylene film, or the like can be used as the release film.

The viscosity of SMC after aging is preferably adjusted to be 5 to 150 kPa · S at 40 ° C. If the viscosity is too low, scumming tends to occur on the surface of the molded product, and if the viscosity is too high, the mold shrinking time tends to be long and the molding cycle tends to be long. However, SMC
The optimum viscosity of the compound is determined by the molding. Further, the viscosity of the SMC compound can be adjusted by the amount of the thickener compounded and the aging conditions. The thickness of one SMC is usually 2 to 3 mm, and usually 5 to 6 sheets are stacked.

In manufacturing the unsaturated polyester resin molded article according to the present invention, two kinds of SMCs with and without a pattern material are prepared. And first, SMC with pattern material
Is placed in the mold on the lower surface, a plurality of SMCs without a patterning material are placed in multiple layers according to the thickness of the product, and the upper mold is used for heating and pressing. Molding temperature is 60
˜150 ° C., and molding pressure is preferably 2 to 10 MPa.

When the molding is performed as described above, the mechanical strength of the molded product is increased, and by reducing the amount of expensive pattern material used, an inexpensive molded product can be manufactured.

[0029]

EXAMPLES Example 1 (Preparation of SMC) 80 parts by mass of unsaturated polyester resin (Polyset PS-9415, trade name of Hitachi Chemical Co., Ltd., styrene solution of 40% by mass of unsaturated polyester resin) dissolved in styrene. And polystyrene dissolved in styrene [polystyrene 40% by mass styrene solution, polystyrene used Denka Styrol (trade name of Denki Kagaku Kogyo Co., Ltd.)] 20 parts by mass, t-butyl peroxypenzoate 1 part by mass, polymerization prohibited Valapenzoquinone as an agent, 0.05 part by weight, zinc stearate as a release agent 4 parts by weight,
Further, 0.8 part by mass of magnesium oxide as a thickener was mixed to prepare an unsaturated polyester resin composition A. Furthermore, the unsaturated polyester resin composition A105.
85 parts by mass of a crushed product of a polyester resin as a pattern material (a crushed product of a cured resin of Polyset PS-9415, the size is 30 mesh and 100 mesh is not passed)
Was mixed in an amount of 15 parts by mass to prepare an unsaturated polyester resin composition B. 100 parts by mass of each unsaturated polyester resin composition obtained by blending in this way was impregnated with 20 parts by mass of glass fiber to prepare SMC with a pattern material and SMC in the pattern material.

Manufacture of Molded Product Using the SMC obtained above, a kitchen counter plate was pressure-heated and molded. First, the SMC with the pattern material was placed on the lower surface of the mold, and further three layers of the SMC without the pattern material were arranged on this, and the upper surface of the mold was heated and pressed. Molding condition is 5k per SMC input weight of product 5kg / sheet
g, additional (lower) SMC input weight 3 sheets 15 kg, charge area 1.5 m ² , molding pressure 7.5 MPa, pressure holding time 4
Molded in minutes. Bending strength of the obtained molded product [JIS K
According to 6911, it was measured by a tensile tester manufactured by Orientec Co., Ltd. Hereinafter, the same] was 75 MPa.
The above is OK.

Example 2 (Preparation of SMC) S containing a pattern material used on the surface of a product
The same MC as in Example 1 was used. 80 parts by mass of unsaturated polyester resin dissolved in styrene (60 parts by mass of styrene, Polyset PS-9117, trade name of Hitachi Chemical Co., Ltd.) and polyethylene dissolved in styrene (40% by mass of polyethylene, 60% by mass of styrene)
20 parts by mass, t-butyl peroxy benzoate 1 part by mass, polymerization inhibitor rose benzoquinone 0.5 parts by mass, mold release agent zinc stearate 1.5 parts by mass, thickener magnesium oxide 1.0. An unsaturated polyester resin composition C was prepared by blending parts by mass. The unsaturated polyester resin composition C was impregnated with a predetermined content of glass fiber to prepare a pattern-free SMC.

(Manufacture of molded product) SMC containing a pattern material is arranged on the lower surface of the mold, and further three layers of SMC using an inexpensive unsaturated polyester resin are arranged thereon, and heating / pressurization is performed by the upper surface of the mold. Molded. The molding conditions are: SMC input weight 5kg on the product side, lower SMC input weight 5kg / sheet x 3 sheets = 1
5kg, charging area 1.5m ² , molding pressure 7.5MP
Molding was carried out at a pressure holding time of 4 minutes. The bending strength of the obtained molded product was 70 MPa.

Comparative Example 1 In Example 1, as the SMC, all SMC containing a pattern material
Was carried out in the same manner as in Example 1 except that The bending strength of the obtained molded product was 60 MPa.

The prices of the SMCs in Examples 1, 2 and Comparative Example 1 are relatively 10 in Example 1.
In the case of 0, for example, 90 of Example 2 and Comparative Example 1
Thing 130.

[0035]

According to the method for producing an unsaturated polyester resin molded article of the present invention, a patterned molded article having excellent mechanical strength can be produced at a lower cost by using SMC.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hidenori Nakano             Hitachi, Shimodate-shi, Ibaraki Prefecture 1250 Shimoeren             Seikou Co., Ltd.Yuki Works (72) Inventor Hiroshi Hasegawa             Hitachi, Shimodate-shi, Ibaraki Prefecture 1250 Shimoeren             Seikou Co., Ltd.Yuki Works F-term (reference) 4F072 AA07 AB09 AD05 AD38 AE01                       AE09 AE12 AE13 AF04 AF24                       AF26 AG03 AG17 AL09                 4J002 AB01Z AC03X BB03X BC03X                       BF02X BG06X BN15Y CC03Y                       CC18Y CD00Y CF00Z CF19X                       CF21W CF21Y CF22W CF25W                       CL00Z CL06Z DE057 DE077                       DJ018 DJ058 DL008 DL009                       EA046 EB126 EB136 EH076                       EH146 EK019 EK039 EK049                       EK059 EK069 EK089 EP016                       EU026 FA04Z FA049 FD01Z                       FD019 FD09Y FD098 FD146                       FD159 FD20X FD337 GC00                       GF00

Claims (3)

[Claims] 1. A plurality of sheet molding compounds in which a fiber base material is impregnated with an unsaturated polyester resin composition containing an unsaturated polyester resin, a polymerizable monomer, a low shrinkage material, a curing agent and a thickener. A method for producing an unsaturated polyester resin molded article by laminating and molding, wherein a pattern material is contained only in a sheet molding compound corresponding to the surface. 2. The method for producing an unsaturated polyester resin molded article according to claim 1, wherein the pattern material is a pulverized product of an unsaturated polyester resin or an inorganic material. 3. In a sheet molding compound corresponding to the surface, the content of the patterning material is 10 to 40% of the whole unsaturated polyester resin composition used.
3. The method for producing an unsaturated polyester resin molded article according to claim 1 or 2.