JP3550848B2 - BMC material and molding method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is a BMC (Bulk Molding Compound) material relates to BMC molding method using the same, and BMC material and molding method for molding a product with a stripe-like pattern in Japanese.
[0002]
[Prior art]
As a molding method of a synthetic resin molded article having a pattern, the following method is known.
(1) A colored ink is printed on the surface of a material, and then charged into a mold for compression molding (Japanese Patent Application Laid-Open No. Sho 60-94319).
(2) A method in which a string-shaped molding compound is overlapped with a sheet molding compound having a different color from that of the string-shaped molding compound, and is heated and pressed (JP-B-58-38300).
(3) A method in which two types of BMCs having different color tones are arranged in a mold, heated and pressurized and mixed simultaneously with casting to form a cloud-like pattern (Japanese Patent Application Laid-Open No. Hei 7-241862).
[0003]
[Problems to be solved by the invention]
In the methods (1) and (2) , the pattern is too clear and only a molded article with an artificial feeling can be obtained.
[0004]
In the method of the above (3) , the pattern boundary is blurred, a natural pattern-like molded body is obtained, but what kind of pattern is formed is not known until the mold is opened. In addition, there is a problem that a molded article having a pattern having excellent design cannot be molded at a high yield.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to provide a BMC material and a molding method capable of molding a molded product having a streak pattern having excellent design properties at a high yield.
[0006]
[Means for Solving the Problems]
The BMC material of the present invention is a BMC material obtained by forming a rod-shaped body of a BMC composition, increasing the viscosity, aligning a plurality of the rods, and twisting the rods together. A coloring agent is attached between the BMC materials, and the colored portion spirals around the outer periphery of the BMC material.
Further, the BMC forming method of the present invention is characterized in that the BMC material is press-formed.
[0007]
In the BMC material, the colored portion is spirally wrapped around the outer periphery of the BMC material by twisting. Therefore, when the BMC material is arranged so as to lie between the molds and press-formed so as to be crushed, a molded body in which a streak pattern derived from a spiral colored portion extends in a substantially parallel direction is obtained.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Explain with the BMC material and molding method of the present invention.
[0009]
But it is not limited especially, but as the BMC formulation according to the present invention can be used in the following formulation.
Unsaturated polyester resin 50 to 100 parts by weight Styrene monomer 0 to 30 parts by weight Low shrinkage agent 0 to 30 parts by weight Polymerization inhibitor 0 to 0.5 part by weight Curing agent 0.5 to 2.0 parts by weight Filler 100 to 400 Parts by weight Internal release agent 2 to 5 parts by weight Thickener 0.5 to 2 parts by weight Glass fiber (preferably about 1.5 to 6 mm in length) 0 to 50 parts by weight
As the low-shrinkage agent, polystyrene, cross-linked polystyrene, polyvinyl acetate, polymethyl methacrylate, a copolymer thereof, a mixture thereof, or the like can be used.
[0011]
As the polymerization inhibitor, mono-t-butylhydroquinone and the like can be used.
[0012]
As the curing agent, an organic peroxide such as t-butyl peroxy-2-ethylhexanate, t-butyl perbenzoate, or the like can be used.
[0013]
As the filler, aluminum hydroxide, glass powder, or the like can be used.
[0014]
As the internal release agent, zinc stearate or the like is preferable, and as the thickener, magnesium oxide or the like is preferable.
[0015]
This blending is an example, and acrylic BMC or the like can also be used .
[0016]
In order to increase the viscosity of the extruded material 10 and the drawn-out body 13 described later, heating may be performed at 30 to 50 ° C. for about 24 to 120 hours in a normal case .
[0017]
Further, when the press forming described later, rather is preferably to charge the torsion combined body 14 to 70% eg 80-90% of the mold 6, the temperature of the flop-less molding 110 to 150 ° C., time 3 The pressure is preferably about ²⁰ to 100 kg / cm ^{2 for} about 30 min.
[0018]
When the surface of the mold surface is rough, the surface pattern of the obtained product becomes blurred, and when the surface of the mold surface is smooth, the surface pattern of the obtained product becomes clear.
[0019]
Next, a description will be given BMC material and molding method according to an embodiment of the present invention with reference to the first to fifth FIG.
[0020]
First, molding the extrudate 10 of the rod-shaped using an extruder 9 as in the first view. After the extruded material 10 is appropriately cut into lengths, the extrudate 10 is thickened to form a rod.
[0021]
A plurality of the rods 11 are aligned in parallel, and then a colorant is supplied between the rods 11 as shown in FIG. 2 (a). As a result, as shown in FIG. 2 (b), a drawn-up body 13 in which the colorant 12 extends in a streak shape between the rod-shaped bodies 11 is formed. In order to perform this coloring, it is preferable to pour the pigment dispersion liquid or the liquid toner onto the aligning body 13.
[0022]
The color between the rods 11 may be the same, or the colors may be different from each other.
[0023]
Thicken the pull aligning member 13 and then combined torsion as Figure 3. In the twisted body 14 (BMC material), a colored portion derived from the colorant 12 spirally wraps around the outer periphery of the twisted body 14. This material is stored in an air-tight bag such as vinyl, taken out of the bag at the time of molding, and provided for molding.
[0024]
As shown in FIG. 4 , the twisted body 14 is placed in the mold 6 and pressed. Thus, the molded body 15 having a stripe-like pattern from the colorant 12 as in the fifth view is molded. When the rod-shaped body 11 is stretched when the twisted body 14 is formed, the pattern of the twisted body 14 is slightly blurred, and the pattern of the press-formed body 15 is also rich in natural feeling .
[0025]
【Example】
(Example 1)
A BMC formulation of the following formulation was prepared.
Unsaturated polyester resin (bis-based) 85 parts by weight Low shrinkage agent (polystyrene) 15 parts by weight Polymerization inhibitor (mono-t-butylhydroquinone) 0.2 parts by weight Curing agent (organic peroxide) 1.0 part by weight Material (aluminum hydroxide, average 50 μm) 150 parts by weight Internal release agent (zinc stearate) 5 parts by weight Thickener (magnesium oxide) 1 part by weight glass fiber (1.5 mm glass chop) 5 parts by weight
Immediately after the preparation, the preparation had fluidity (1000 to 2000 ps) enough to hang under its own weight .
[0027]
This mixture was extruded into a round bar having a diameter of 20 mm to obtain an extrudate 10. This extruded material was cut into a length of 300 mm, and was thickened under conditions of 40 ° C. × 2 days to obtain a rod-shaped body 11. The four rods 11 are aligned as shown in FIG. 2 (a) , and then 10 g of a coloring agent consisting of 100 parts by weight of a white toner, 100 parts by weight of aluminum hydroxide, and 1 part by weight of a curing agent are poured into the aligned body 13. In this way, a drawn body 13 shown in FIG. 2 (b) was manufactured. BMC material 14 (diameter 70 mm, length 150 mm) consisting of the twisted body shown in FIG. 3 was manufactured by twisting the aligned bodies 13. This BMC material 14 was press-molded under the conditions of 50 kgf / cm ² , 140 ° C., and 10 minutes to produce a plate-shaped molded body 15 of 200 × 200 × 10 mm. The pattern of the molded body 15 was a fine streak pattern with a rich natural feeling.
[0028]
【The invention's effect】
As described above, according to the BMC material and the molding method of the present invention, a product having a predetermined streak pattern can be molded. This pattern is rich in blurred natural feeling, and the quality of the product is very high.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an extrusion method when manufacturing a BMC material of the present invention.
FIGS. 2A and 2B are a perspective view and a cross-sectional view illustrating a pull-out body.
FIG. 3 is a perspective view of a twisted body.
FIG. 4 is a sectional view showing a press molding method.
FIG. 5 is a perspective view showing a molded body 15;
[Explanation of symbols]
6 Mold 11 Bar-shaped body 12 Colorant 13 Aligned body 14 Twisted body (BMC material)
15 molded body

Claims (2)

A BMC material obtained by forming the rod-shaped body of the BMC, thickening, and aligning a plurality of the rod-shaped bodies, and then twisting the rod-shaped bodies together,
A BMC material in which a coloring agent is attached between the aligned rods, and a colored portion spirals around the outer periphery of the BMC material. A BMC forming method, comprising press-forming the BMC material according to claim 1 .

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