JP2000326352A - Manufacture of decorated molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a decorated molded product having a transparency, a depth and a beautiful appearance wherein mixing of a resin component of one molding material and a resin component of the other molding material and exudation are prevented from occurring, a boundary between a decorated face and the other part is distinct, it is free from surface defects such as generation of a pinhole, surface blushing or the like, and various designs represented by a grain tone can be demonstrated. SOLUTION: In the decorated molded product 30, a glass mat 30b is placed between BMC 30a containing a decoreating patterning agent and SMC 30c not having a decorating pattern agent, it is clamped in a mold 10 comprising a stationary mold 11 and a movable mold 12, and thermally cured. In this case, deairing is executed by suction so that a pressure of an inside of the mold 10 becomes <=160 mmHg under the absolute pressure until the movable mold 12 comes in contact with the BMC 30a in clamping, and on and after the deairation by suction so that 310-560 mmHg absolute pressure is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a decorative molded product which can express various designs represented by a stone-grained tone, and has a clear and deep feeling and a beautiful appearance.

[0002]

2. Description of the Related Art A fiber-reinforced unsaturated polyester resin molding material containing a decorative pattern agent (stone-patterned SMC) and a fiber-reinforced unsaturated polyester resin molding material containing no decorative pattern agent (ordinary SMC) ), A sheet-shaped separating material (glass mat) is sandwiched, and this is clamped in a mold composed of a fixed mold and a movable mold. The production method is known (for example, see JP-A-63-4915).

[0003] Thus, the stone-patterned SMC and the ordinary S
When a decorative molded product is manufactured by sandwiching a glass mat between the MC and the MC, a decorative molded product having a decorative surface with a stone pattern can be obtained, and the resin component of one SMC and the other SM
There is an advantage that mixing and bleeding with the resin component of C is prevented, and a decorative molded product in which the boundary between the decorative surface and another portion is clear can be obtained.

[0004]

However, in the above-mentioned conventional method of manufacturing a decorative molded product, the decorative molding obtained due to air remaining between each SMC molding material and the glass mat. Pinholes may occur on the surface of the product.

In order to prevent the above-mentioned pinhole from being generated, the inventor strongly suctions and degassed the inside of the mold at the time of mold clamping, thereby removing the residual air causing the pinhole. Although an attempt was made to remove them, when using a fiber-reinforced unsaturated polyester resin molding material containing a decorative patterning agent as described above (stone-patterned SMC), the occurrence of pinholes can be prevented, It turned out that there is a problem that the surface of the obtained decorative molded article is whitened and the appearance is significantly deteriorated.

[0006]

In order to solve the above-mentioned problems, as a result of further investigation, it was found that pinholes were generated and the surface was whitened by suctioning and degassing the inside of the mold under specific conditions during mold clamping. Can be prevented.

That is, the present invention provides a sheet-like separator between a fiber-reinforced unsaturated polyester resin molding material containing a decorative pattern agent and a fiber-reinforced unsaturated polyester resin molding material not containing a decorative pattern agent. In the method of manufacturing a decorative molded product in which the mold is clamped and heat-cured in a mold composed of a fixed mold and a movable mold, the movable mold comes into contact with the one molding material during mold clamping. 160m inside mold with absolute pressure
The suction and deaeration is performed so as to be not more than mHg, and thereafter, the suction and deaeration is performed so that the absolute pressure is 310 to 560 mmHg.

[0008] In the present invention, as a fiber-reinforced unsaturated polyester resin molding material containing no decorative pattern agent, a known ordinary SMC or BMC containing a decorative pattern agent is used.
MC and BMC are preferably used. In particular, it is preferable to use SMC from the viewpoint of moldability, and the thickness of these SMCs is generally 1 to 10 mm, particularly 1 to 5 mm.
mm is preferred.

As the fiber-reinforced unsaturated polyester resin molding material containing a decorative patterning agent, the above-mentioned ordinary SM is used.
SMC or BMC in which a decorative pattern agent is added to C or BMC is preferably used. In particular, BM containing a decorative patterning agent
C is good because the size of the flaky material used is not limited as compared with SMC, and relatively short glass fibers are used as compared with SMC, and the glass fibers are sufficiently opened. It is most suitable to use BMC containing a decorative patterning agent because it provides a high degree of transparency and a sense of depth.

[0010] Decorating pattern agents include colored mica (white mica and black-and-white mica), colored aluminum flakes, colored polyethylene films, vinyl chloride films, polycarbonate films, polyester films, and other colored plastic film fragments. And an average size of 0.1 to 4.0 mm, preferably an average size of 0.1 to 4.0 mm
A 2.5 mm colored flaky material is preferably used. And it is preferable to contain in the range of 0.5 to 20 weight%. By adding such a decorative pattern agent, it is possible to express various designs represented by a stone-grained tone, and to obtain a decorative molded article having a clear or deep feeling and a beautiful appearance.

It is preferable to use a mixture of different sizes of such decorative pattern materials, rather than using only those having the same size, because a decorative molded article having a good design can be obtained. . In addition, as a natural stone tone, a marble tone or a granite tone is generally considered, and there are various types of stone tone such as whitish, blackish, and reddish. It is preferable to use two or more colors of decorative pattern materials in order to realize the stone texture of the present invention.

Further, the sheet-like separating material is for preventing the resin component of one molding material and the resin component of the other SMC from being mixed or exuding. A cloth, a nonwoven fabric, a glass mat, or the like is used, and a glass mat is particularly preferably used. The glass mat may be slightly impregnated with a thermosetting resin such as an unsaturated polyester resin.

In the present invention, a mold such as a matched die, which is composed of a fixed mold and a movable mold preheated to a predetermined temperature and is configured to be capable of sucking and deaerating the inside of the mold, is used. Then, for example, a fiber-reinforced unsaturated polyester resin molding material containing the decorative pattern agent, which is room temperature or preheated, is placed on a fixed mold and heated, and a sheet-like separator is placed thereon, Further, a fiber-reinforced unsaturated polyester resin molding material containing no decorative patterning agent is placed thereon, and the movable mold is moved down to clamp the mold at a desired speed and pressure.

Each molding material is cut into an appropriate size, and a plurality of such materials are stacked in a required amount and placed at a predetermined position. The sheet-like separating material is also cut into an appropriate size and placed at a predetermined position. In this case, the fiber-reinforced unsaturated polyester resin molding material containing the decorative pattern agent is for forming the decorative surface of the molded product, and may be placed so as to cover the entire surface, It may be placed so as to cover only necessary parts.

The mold is generally heated by an electric heating system or a steam system, and is generally clamped by a hydraulic press. The mold temperature is generally 120-160 ° C, and the mold clamping pressure is generally 20-1.
It is performed at 50 kg / cm ² . The mold closing speed is generally 0.
It is about 3 to 30 mm / sec. The mold closing speed is
It may be performed at a constant speed from the beginning to the end, or may be performed while reducing the speed in several steps. After completion of the mold clamping, the pressure is generally maintained for about 1 to 20 minutes.

In the present invention, however, the movable mold descends until the movable mold comes into contact with one molding material (for example, a fiber-reinforced unsaturated polyester resin molding material containing no decorative patterning agent). 160mmH at absolute pressure inside the mold
g or less, and thereafter it is necessary to perform suction and deaeration so that the absolute pressure becomes 310 to 560 mmHg. The absolute pressure is a pressure indication based on vacuum, and is obtained by adding the atmospheric pressure to the gauge pressure (pressure indication based on the atmospheric pressure as zero reference).

As described above, if the inside of the mold is strongly suctioned and degassed at an absolute pressure of 160 mmHg or less until the movable mold comes into contact with one molding material, air remaining between each molding material and the glass mat can be satisfactorily removed. It has been found that pinholes are less likely to be formed on the surface of the decorative molded article obtained by the removal. After that, it was found that by appropriately suctioning and degassing so that the absolute pressure becomes 310 to 560 mmHg, whitening of the surface of the obtained decorative molded product can be prevented.

After the movable mold comes into contact, the absolute pressure is 560 mm
If the suction and degassing are weaker than Hg, pinholes will be generated even if the suction and degassing are strong at 160 mmHg or less before the movable mold comes into contact. Conversely, if the absolute pressure is suctioned and deaerated more than 310 mmHg after the movable mold comes into contact, the surface of the obtained decorative molded product becomes white.

(Operation) As described above, the reason why the generation of pinholes and the whitening of the surface can be prevented by suctioning and degassing the inside of the mold under specific conditions at the time of mold clamping is presumed as follows. You. That is, the generation of pinholes is caused by residual air, and the stronger the suction and deaeration, the more residual air is removed and the number of pinholes is reduced. On the other hand, surface whitening is caused by the fact that gelling starts before the molding material in contact with the fixed mold closes the mold due to heat, resulting in the formation of microscopic white lumps. The harder the surface in contact with air (oxygen), the longer the hardening of the surface and the less visible surface whitening. Therefore, when the mold is suctioned and degassed under the specific conditions as described above at the time of mold clamping,
Both actions combine to provide good control of both pinholes and surface whitening.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples and comparative examples of the present invention are shown below. (Example 1) <Preparation of BMC containing decorative pattern agent> An unsaturated polyester resin obtained by dissolving a hydrogenated bisphenol-based unsaturated polyester having a number average molecular weight of 2,600 in a styrene monomer (styrene monomer concentration: 40% by weight) ) 80 parts by weight, 20 parts by weight of a resin for preventing shrinkage in which polystyrene having a number average molecular weight of 120,000 is dissolved in a styrene monomer (styrene monomer concentration: 50% by weight), 1 part by weight of a curing catalyst (t-butyl peroxybenzoate), 220 parts by weight of an inorganic filler (aluminum hydroxide having an average particle diameter of 12 μm), 2 parts by weight of a chemical thickener (magnesium oxide), 5 parts by weight of zinc stearate, glass fiber for reinforcement (average cut length of 6 mm)
Long glass fiber chop) 12 parts by weight and white pigment 0.
5 parts by weight were blended.

Further, 17 parts by weight of a decorative pattern material (each having a thickness of 12
μm of a colored polyester film), and the resulting mixture was mixed in a conventional BMC manufacturing apparatus (kneader), aged at 40 ° C. for 2 days, and mixed with a decorative patterning agent containing B.
MC was prepared. This is 5m thick by cold pressing
m.

Decorating pattern material (20 parts by weight) Black: size (average) 0.2 mm (6 parts by weight), size (average) 1.5 mm (6 parts by weight) Brown: size (average) 0 0.2 mm (2 parts by weight) White: Size (average) 0.5 mm (3 parts by weight)

<Preparation of SMC not containing decorative pattern material>
80 parts by weight of an unsaturated polyester resin (styrene monomer concentration 40% by weight) in which an isophthalic unsaturated polyester having a number average molecular weight of 2,500 is dissolved in a styrene monomer, and polystyrene having a number average molecular weight of 120,000 are dissolved in a styrene monomer. 20 parts by weight of a resin for preventing shrinkage (styrene monomer concentration of 50% by weight), 1 part by weight of a curing catalyst (t-butyl peroxybenzoate), 140 parts by weight of an inorganic filler (calcium carbonate having an average particle diameter of 12 μm),
1 part by weight of a chemical thickener (magnesium oxide), 5 parts by weight of zinc stearate and 0.5 part by weight of a white pigment are blended,
A paste of the resin composition was prepared.

Using a conventional SMC manufacturing apparatus, a paste of the resin composition is applied to one surface of one carrier film (polyethylene film), and a paste of the resin composition is applied to one surface of the other carrier film. ,
The coated surfaces of both carrier films are sandwiched via a glass fiber chop layer (fiber length 1 inch), and the glass fiber chop layer is impregnated with both pastes, and this is aged at 40 ° C. for 2 days. Thicken 2mm thick
No SMC containing the decorative pattern material was produced. The glass fiber chop layer was adjusted to 24% by weight of the whole.

<Manufacture of decorative molded article>
BMC that has 1170mm length x 870mm width
Each one was prepared. In addition, the decorative pattern material
The SMC that does not have it is cut into 1100 mm length × 740 mm width.
Three cut pieces were prepared. In addition, 1170mm in length
Glass chopped strander cut to 870mm in width
(450 g / m ^Two) Was prepared.

As shown in FIG. 1 (A), it is composed of a convex fixed mold 11 and a concave movable mold 12, and the inside of the mold can be suctioned and deaerated by a suction pump 20 through a pipe 21. Mold for Matched Toilet Bread (Matched Die)
10, the fixed mold 11 is 145 ° C., and the movable mold 12 is 12
Heat to 5 ° C., place one BMC (charge rate 100%) 30a containing the decorative pattern material on the fixed mold 11, and place one glass chopped strand mat 30b thereon ( (A charge rate of 95%), and three SMCs (charge rate of 80%) 30c that do not contain the decorative pattern material are placed thereon, and the movable mold 12 is placed at 1.0 mm / sec. And the mold was clamped. 65 kg
After holding the pressure for 10 minutes at a pressure of / cm ^2, the mold 10 was opened and the mold was released, and a decorative molded product (toilet pan) 30 having a length of 1170 mm, a width of 870 mm and a depth of 25 mm was manufactured. By repeating this, a total of 10 decorative molded products (toilet pans) were manufactured.

At this time, the inside of the mold 10 was suctioned and degassed at an absolute pressure of 130 mmHg until the movable mold 12 began to descend and came into contact with the SMC 30c containing no decorative pattern material. Thereafter, as shown in FIG. 1 (B), the movable mold 12 is formed at a rate of 1.0 mm / sec while each molding material flows while the movable mold 12 is flowing. After contacting the SMC 30c containing no, the sample was suctioned and degassed so that the absolute pressure was 540 mmHg. In addition, 1
Reference numeral 3 denotes a seal member made of an O-ring. The inside of the mold 10 is sealed by the seal member 13 so that a desired degree of vacuum is maintained.

The obtained 10 decorative molded articles (toilet pans) were stone-like, transparent and deep. Surface defects (pinholes) were examined for the obtained 10 decorative molded products (toilet pans), and the incidence of pinholes (the number of pinholes / 10) is shown in Table 1.
Furthermore, the presence or absence of surface whitening was examined for the obtained 10 decorative molded articles (toilet pan), and the occurrence rate of surface whitening (the number with surface whitening / 10) was shown in Table 1.

(Embodiment 2) After the movable mold 12 comes into contact with the SMC 30c which does not contain the decorative pattern material, the movable mold 12 has an absolute pressure of 380.
Suction and degassing were performed so that the pressure became mmHg. Other than that, it carried out similarly to Example 1. Table 1 shows the results.

(Comparative Example 1) After the movable mold 12 came into contact with the SMC 30c containing no decorative pattern material, the movable mold 12 was subjected to 590 absolute pressure.
Suction and degassing were performed so that the pressure became mmHg. Other than that, it carried out similarly to Example 1. Table 1 shows the results.

(Comparative Example 2) After the movable mold 12 came into contact with the SMC 30c containing no decorative pattern material, the movable mold 12 was subjected to 260 absolute pressure.
Suction and degassing were performed so that the pressure became mmHg. Other than that, it carried out similarly to Example 1. Table 1 shows the results.

(Comparative Example 3) Even after the movable mold 12 came into contact with the SMC 30c containing no decorative pattern material, suction and deaeration were continued so that the absolute pressure was 130 mmHg. Other than that, it carried out similarly to Example 1. Table 1 shows the results.

(Comparative Example 4) No suction degassing was performed. Other than that, it carried out similarly to Example 1. Table 1 shows the results.

[0034]

[Table 1]

[0035]

As described above, according to the method for producing a decorative molded product of the present invention, mixing and exudation of the resin component of one molding material and the resin component of the other molding material are prevented, The boundary between the surface and other parts is clear, and there are no pinholes or surface defects such as surface whitening, so that various designs represented by stone-grain can be expressed, and there is a sense of transparency and depth. A decorative molded article with a beautiful appearance can be obtained.

Therefore, the method for producing a decorative molded product of the present invention can be suitably used for producing FRP molded products such as bathtubs, waterproof pans and other housing equipment and automobile members using SMC and BMC.

[Brief description of the drawings]

FIG. 1 shows an example of a method for producing a decorative molded product of the present invention,
(A) is an explanatory view at the time when the movable mold comes into contact with the molding material at the time of mold clamping, and (B) is an explanatory view at a time thereafter.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 Mold (matched die) 11 Fixed mold 12 Movable mold 13 Sealing material (O-ring) 20 Vacuum pump 21 Piping 30 Decorative molded product 30a Molding material containing decorative pattern material (BMC) 30b Sheet-shaped separator (glass) Mat) 30c Molding material that does not contain decorative pattern material (BMC)

Claims (2)

[Claims] 1. A sheet-like separator is sandwiched between a fiber-reinforced unsaturated polyester resin molding material containing a decorative pattern agent and a fiber-reinforced unsaturated polyester resin molding material not containing a decorative pattern agent. In a method of manufacturing a decorative molded product, in which a mold is clamped and heat-cured in a mold composed of a fixed mold and a movable mold, the mold is closed until the movable mold comes into contact with one of the molding materials during mold clamping. Suction and degas so as to be 160 mmHg or less in absolute pressure, and thereafter, 310 to 560 in absolute pressure
A method for producing a decorative molded product, wherein the decorative molded product is suctioned and degassed to have a pressure of mmHg. 2. A fiber-reinforced unsaturated polyester resin molding material containing a decorating pattern agent, comprising a bulk molding compound (BMC) containing a decorating pattern agent, and a fiber-reinforced unsaturated polyester resin containing no decorating pattern agent. The method for producing a decorative molded product according to claim 1, wherein the saturated polyester resin molding material comprises a sheet molding compound (SMC) containing no decorative patterning agent, and the sheet-like separating material comprises a glass mat.