JPH0679836A - Laminated sheet-like molding material and preparation of molded item using it - Google Patents

Abstract

PURPOSE:To provide a required surface quality even when a recycled powder of a waste product or a used waste product is reused by forming a layer contg. no recycled powder on one or both sides of a layer wherein a recycled powder prepd. by grinding a molded item of a fiber-reinforced plastic is incorporated as a filler. CONSTITUTION:In a method for preparation of an SMC and a molded item of the SMC wherein a waste of a fiber-reinforced plastic molded item is ground and the ground product is added to a sheet-like molding material (SMC) to reuse it, the ground sheet-like molding material (SMC) is thickened in an aging room based on the ordinary method and a molded item is obtd. by performing compression molding under specified temp. and pressure. In this case, when the SMC molding material is fed between molds 18 and 19, the compression molding is performed in such a way that a layer of a compd. incorporated with no recycled powder is formed on the side 21 corresponding to the side where importance is attached to the appearance of the molded item. It is obtd. thereby an SMC molded item having a required surface quality on the side being visually observed by the people.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an SMC and a SMC for reusing a waste material of a fiber reinforced plastic (hereinafter referred to as FRP) molded product after crushing it and adding it to a sheet-shaped molding material (hereinafter referred to as SMC). The present invention relates to a method for producing an SMC molded product by using.

[0002]

2. Description of the Related Art A conventional laminated SMC molding material is prepared by charging one unsaturated polyester resin compound into two tanks 3 and 4 as shown in FIG. In order to strengthen the resin mixture by casting the resin blends 1 and 2 on the carrier films 9 and 10 delivered from the rolls 7 and 8 by controlling the discharge amount with the doctor blades 5 and 6, glass fiber, etc. The roving 13 of the chopped strand 1 with a cutter 14 is usually about 1 inch long.
It was cut into 5 pieces, sprayed on the resin compound coating layer 12 on one side, then laminated on the other coating layer 11, pressure-bonded by a pressure roller 16 and wound by a winding roller 17 to manufacture. Then, as shown in FIG. 2, a desired amount of the SMC 20 is measured from the roll 17, and the compression molding die 18,
SMC 20 shown in FIG. 3, which is composed of a plurality of layers such as an outer layer 21 and an inner layer 22, is inserted between 19 and the molds 18 and 19 are closed to compress and harden the SMC 20 at a predetermined temperature, pressure and time. The molded product 23 was obtained.

The 36th F hosted by the Reinforced Plastics Association, held at the Science and Technology Center of Osaka City, October 29-31, 1991
The FRP, which is said to be difficult to recycle, is described in pages 185 to 188 (hereinafter referred to as Reference 1) of the abstract summary of the RP general lecture.
The molded article is described as being technically or economically recyclable. SMC as a representative of FRP molded products
By crushing and finely pulverizing the waste of the molded product to replace a part of the filler in the SMC composition, adding about 10% of the total weight to make it SMC, and further compression molding, Manufactures and uses automobile parts, housing equipment and other parts.

[0004]

Although the method disclosed in Document 1 makes it possible to recycle an FRP molded product,
When about 10% by weight or more of regenerated pulverized powder (hereinafter referred to as regenerated powder) is added to a new compound, the physical properties of SMC molded products are lower than those of non-added products, and the surface smoothness of molded products is lost. In addition, there is a problem that undesired coloring occurs. INDUSTRIAL APPLICABILITY The present invention provides a laminated SMC molding material capable of imparting a desired surface quality even if a waste product from the FRP molding process or a recycled powder of a used waste product from a general user and a molded product using the same are manufactured. The purpose is to provide the law.

[0005]

The present invention provides a laminated SMC molding material in which a layer containing no recycled powder is disposed on one or both sides of a layer containing recycled powder obtained by crushing an FRP molded product as a filler. Of the SMC molding material, a layer containing no recycled powder is placed on the side where the appearance of the molded product is emphasized and supplied into the molding die,
The present invention relates to a method for producing a molded product for compression molding.

In the present invention, a laminated SMC is obtained as a molding material mainly by the method as shown in FIG. 1, but different resin compounds are prepared in the tanks 3 and 4 at this time. That is, for example, tank 3 contains a resin mixture of unsaturated polyester (compound a) to which recycled powder is not added, and tank 4 contains resin mixture of unsaturated polyester (blend b) containing a desired amount of recycled powder. And). Here, as the regenerated powder, an FRP molded product (usually an unnecessary waste product) is pulverized, and the molded product is preferably an SMC molded product. The particle size of the regenerated powder is not particularly limited. In addition, the compounds a and b may be exchanged and used in the tanks 3 and 4. Further, it is desirable to use the same type of base resin for the blends a and b, but as the laminated SMC, the layer of the blend a and the layer of the blend b are well fused at the interface at the time of bonding, It is not particularly limited to the same type as long as it is confirmed that the physical properties of the obtained molded product are not significantly affected.

In FIG. 1, the different blends a and b are made up of doctor blades 5 and 6 in consideration of their respective viscosities and coating amounts.
Is adjusted and the desired amount is cast-coated on the carrier films 9 and 10. Then, in the same manner as in the conventional method, a fiber reinforcement such as glass fiber is sprinkled on one of the compound coating layers,
The other compound coating layer is laminated, pressure-bonded by a pressure roll, and wound by a winding roll to obtain a laminated SMC molding material.

The SMC molded product is obtained by subjecting the above SMC molding material to thickening in a aging chamber by a conventional method to improve the handleability at the time of molding, and then compression molding at a predetermined temperature, pressure and time. In the present invention, the mold 1 is obtained in FIG.
When supplying the SMC molding material between 8 and 19, the a of the SMC molding material is provided on the side corresponding to the side (explained as the outside of the molding) where the appearance of the molded product is important.
Allow layers (layers of formulation with no reconstituted powder added) to come. When the hues due to the difference in the composition of the a layer or the b layer cannot be distinguished, either one of the layers is mixed with a small amount of a dye or pigment, or one of the carrier films 9 and 10 is applied with a different color film. For example, the a layer and the b layer can be easily distinguished from each other. In this way, an SMC molded product having a desired surface quality on the human visual side is obtained.

In place of the carrier film roll 8 and the carrier film 10 in FIG. 1, a sheet-shaped molding material in which one layer of the compound containing no recycled powder is previously coated on the carrier film is supplied. By doing so, it is possible to manufacture an SMC sheet having a three-layer structure having a layer containing recycled powder as a core. Further, another set of a resin storage tank and a doctor blade are provided on the upstream side with respect to the moving direction of the carrier film, and the resin compound coating layer 12 is made into a multi-layer, that is, the compound containing no recycled powder is first coated.
An SMC having a three-layered laminated structure is also obtained by sprinkling a fiber reinforcement on it and then applying a composition containing recycled powder to replace both the carrier film roll 8 and the carrier film 10 in FIG. Can be manufactured. A laminated SMC having a laminated structure of three or more layers can be manufactured by laminating by the above two methods.

In the case of a two-layer SMC, the laminated SMC manufactured in this manner has its front and back clarified, and for example, it has been distinctly distinguished by coloring each layer in advance.
The required amount is weighed out and supplied into the mold so that the side not containing regenerated powder is the outside of the molded product, and compression molding is performed. Three layers S
In the case of MC, it is not necessary to make a strict distinction because a composition containing no regenerated powder is placed on both outer sides of the three layers. The SMC molded product manufactured in this manner is a molded product having a high quality outer surface while having an unfavorable layer containing a large amount of recycled powder on the back surface or inside thereof, and is currently produced in large quantities. It has the same surface quality as Class A-SMC.

[0011]

EXAMPLES Next, examples of the present invention will be described. The resin compositions of the layer a and the layer b were prepared with the blending composition (unit is% by weight) shown in Table 1, respectively. The following materials were used for each material. That is, the fiber reinforcement is glass fiber FER0782A manufactured by Fuji Fiber Glass, the unsaturated polyester resin (unsaturated PE resin in the table) is Hitachi Chemical Co., Ltd. Polyset 9120, and is a polymerizable monomer that also serves as a viscosity adjustment. A styrene monomer manufactured by Sumitomo Chemical was used. The composition ratio (% by weight) of auxiliary agents such as a curing agent is 70% of a low-shrinking agent saturated polyester (manufactured by Hitachi Chemical Co., Ltd., Polyset 9201) and a curing agent of t-butylperoxybenzoate (manufactured by NOF Corporation).
Of 10%, zinc stearate (made by NOF CORPORATION) as a releasing agent and 15% of magnesium oxide (made by Kyowa Chemical Industry Co., Ltd.) as a thickening agent. The filler is calcium carbonate (manufactured by Nitto Koka Kogyo Co., Ltd.) and a regenerated powder that replaces part or all of the calcium carbonate. The regenerated powder is an SMC molded product, which is a crushed used product of automobile exterior parts painted in black. An unclassified product having a particle equivalent diameter of 0.1 to 4000 μm was used. The amount of the fiber reinforcing material was set so that the total amount of SMC produced was 25 or 30 wt% when the thicknesses of the a layer and the b layer were 1: 1. The thickener magnesium oxide was mixed with the resin mixture in the step immediately before casting.

A laminated SMC having a two-layer structure is manufactured by the manufacturing method shown in FIG.
Cut 60 g (area size of about 350 x 350 mm) and fill a compression molding die that can form a SMC flat plate of 360 mm length x 360 mm width x 2.0 mm thickness, pressure 10MP
Compression molding was performed under the conditions of a, mold temperature of 150 ° C., and heating / pressing time of 100 seconds. The surface quality of this plate was evaluated and the results are shown in Table 1. In the table, the surface smoothness index is based on the Ashland method of the United States, and the lower the value, the better. The degree of coloration is evaluated by visual observation, A is a natural color and is good, B is cloudy, and C mark indicates that coloring is remarkable. The comprehensive evaluation is the surface quality that is the total of the surface smoothness index and the degree of coloration. O indicates that the surface quality is good, Δ indicates that it is slightly defective, and X indicates that it is defective.

In Table 1, Comparative Examples 1 to 3 are only resin blends containing recycled powder, and Comparative Example 1 is b _{1 of} Example _1.
Layer, Comparative Example 2 is the b ₂ layer of Example 2, Comparative Example 3 is Example 3
It has the same composition as the b ₃ layer. Comparative Example 4 is a resin composition containing no recycled powder, and
It has the same formulation composition as _one layer. From Table 1, a of Comparative Example 1
The b ₁ layer, which is not hidden by the layer, has a surface smoothness index of 150 and is markedly colored by visual evaluation, and is a normal class A SMC (index of 100 or less for practical use as exterior parts for automobile exterior parts, housing equipment and electrical products). However, the surface smoothness index of 80 is the same as in Comparative Example 4 in which only the a layer is formed, and the a layer as the SMC which has been widely and conventionally used in Example 1 is laminated on the surface. The visual evaluation is also good. The surfaces of Comparative Examples 2 and 3 are unsatisfactory, but the surface quality of Examples 2 and 3 is good with the same results as Example 1.

[0014]

[Table 1]

[0015]

EFFECTS OF THE INVENTION According to the present invention, the waste products from the FRP molding process, from general users, without deteriorating the surface quality such as surface smoothness of SMC molded products and deteriorating the physical properties of the molded products. It becomes possible to use recycled powder such as used waste products.

[Brief description of drawings]

FIG. 1 is a conceptual diagram illustrating a method for manufacturing an SMC.

FIG. 2 is a conceptual diagram illustrating a compression molding method for an SMC molded product.

FIG. 3 is a conceptual diagram of a cross section of an SMC molded product.

[Explanation of symbols]

1, 2 ... Unsaturated polyester resin blend, 3, 4 ... Tank, 5, 6 ... Doctor blade, 7, 8 ... Carrier film roll, 9, 10 ... Carrier film, 11, 12
... Resin compound coating layer, 13 ... Roving, 14 ... Cutter, 15 ... Chopped strand, 16 ... Crimping roll,
17 ... Winding roll, 18, 19 ... Compression mold, 20
... SMC, 21 ... Outer layer, 22 ... Inner layer, 23 ... SMC molded product

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B32B 27/12 7258-4F // B29K 105: 08 B29L 9:00 4F

Claims (4)

[Claims] 1. A laminated sheet-shaped molding material in which a layer containing no regenerated powder is arranged on one side or both sides of a layer containing regenerated powder obtained by crushing a fiber-reinforced plastic molded product as a filler. 2. The laminated sheet-shaped molding material according to claim 1, wherein the regenerated powder is obtained by crushing a molded product of the sheet-shaped molding material. 3. The laminated sheet-shaped molding material according to claim 1, wherein a layer containing no regenerated powder is arranged on the side where the appearance of the molded product is considered important, and is supplied into a molding die for compression molding. And the method of manufacturing molded articles. 4. A molded product manufactured by the manufacturing method according to claim 3.