JPH05176855A - Thermoplastic resin bath tub and method of making it - Google Patents

Abstract

PURPOSE:To enable application as bath tub with a circulation boiler by combining a thermoplastic surface material and a reinforced thermoplastic sheet blended with a fiber as backup material to obtain resistance to boiling comparable to the bath tub made of thermosetting resin in the past. CONSTITUTION:Surface material A on the side of water bathing is made of a thermoplastic resin with the heat deformation temperature exceeding at least 100 deg.C under a load of 18.6kg/cm<2> and as a backup material B, a fiber reinforced thermoplastic resin is employed. Both materials are laminated integrally to make a bath tub C. The resin as the surface material A, a resin with excellent heat resistance such as polyacetal or polybutyleneterephthalate which provides a resistance to boiling comparable to ordinary bath tubs made of a thermosetting resin in the past is employed and the mounting of a circulation boiler is possible. Then, the resin usable as the backup material B is a medium or long fiber such as glass fiber at a rate of 10-50wt.% per 100wt.% of the thermoplastic resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin bathtub used in a composite room unit of a condominium or a hotel, a bathtub unit in a detached house, and a method for producing the same. More specifically, it is made of a fiber-reinforced thermoplastic resin. The present invention relates to a bathtub and its manufacturing method.

[0002]

2. Description of the Related Art In recent years, composite room units and bath units made of synthetic resin have been widely used as described above. Generally, unsaturated polyester resin is mixed with glass fiber as a material thereof. So-called fiber reinforced thermosetting resin (FRP) is used. These units include hand laid-up products, cast products such as artificial marble, and press-molded products by SMC. In this FRP unit, generally, a circulating hook can be attached.

On the other hand, fiber reinforced thermoplastic resin (FRTP)
Although there is also a unit based on the above, generally, there is known a unit in which FRP or a wooden mold is used as a backup material in a polypropylene injection molded product or an acrylic sheet vacuum molded product. However, due to problems with the material, it is necessary to avoid the danger of emptying or boiling, and the hot water supply type is the main type.

[0004]

The former FRP unit has some major features, but it may be pointed out. That is, in the case of hand lay-up molding, a molded product having a depth such as a large bathtub with a wash basin or a shower room can be formed with an inexpensive resin mold, but the productivity is poor and the product is limited to a small amount. Will end up. In addition, in the case of cast products using male and female molds, high-quality type with transparency using artificial marble etc.
Although high-strength and high-grade molded products can be obtained by RTM molding (resin transfer molding), they also have poor productivity. Further, in the case of press molding using SMC or BMC, the productivity is significantly improved, but on the other hand,
Large-scale press and pressure resistant mold are required, resulting in large capital investment.
In addition, this method is not suitable for various patterns and colors.

In particular, in the FRP type, there is almost no possibility of recycling, and at present, the main disposal method is landfill disposal. In addition, it is difficult to make the volume of the molded product compact at the time of its disposal, which is a serious problem in terms of the disposal method.

In the latter FRTP unit,
The surface material on the water bath side is mainly polypropylene (PP) or acrylic (PMMA) sheet. When the heat distortion temperature is 18.6 kg / cm ² load, PP is 57 to 63 ° C.,
PMMA has a boiling resistance of 68 to 99 ° C., which is 100 ° C. or less, and is inferior in boiling resistance, so that it is difficult to use PMMA in a bath equipped with a circulation pot.

In many cases, FRP material is used as a backup. In this case, the backup material is FR.
Since it is P, the productivity is low and the recycling is difficult, and further, the adhesiveness at the interface between the two is poor, and if the bonding method is not suitable, there is a problem that problems such as blistering of the resin occur. ..

[0008]

The present invention has been achieved as a result of intensive research to solve the above-mentioned problems of the prior art. The first invention is the water bath side. The surface material is a thermoplastic resin having a heat deformation temperature of at least 100 ° C. or more under a load of 18.6 kg / cm ² , and a fiber-reinforced thermoplastic resin is used as a backup material to be laminated and integrated. It depends on.

In a second aspect of the invention, the thermoplastic resin sheet and the fiber reinforced thermoplastic resin sheet are heated and softened and then vacuum or pressure molded to form a surface material and a backup material, respectively, and then both of them. A method of manufacturing a thermoplastic resin bath, characterized in that they are laminated and integrated, and in some cases, in the molding of the backup material, the mold is 5 mm or more and 30 m or more.
Level up below m and the density of backup material is 1.
It is intended to provide a method for producing a bath which is foam-molded so as to be 2 or less.

In the present invention, a thermoplastic resin sheet is used as the surface material of the bathtub, and on the other hand, a thermoplastic resin sheet reinforced by blending fibers is used as the backup material to integrate these. 1 is a cross-sectional view of the molded bath C, which is a molded product entirely molded of a thermoplastic resin. In the figure, A is a surface material on the water bath side, and B is a backup material. Note that the backup material B of FIG. 2 is an example in which many gas bubbles are entrained in the resin.

The manufacturing method as the second invention is various in concrete terms. First, as the first method, the surface material sheet is used.
There is a method in which the sheet is draw-formed by vacuum forming, pressure forming or transfer press forming, while the backup fiber reinforced sheet is similarly drawn and integrally formed with the surface material.

As another example, the surface material is drawn as described above, then the peripheral portion is trimmed, and this is inserted into a die for press molding. Further, a thermoplastic resin sheet (stampable sheet) reinforced by blending fibers, which is previously melted in a mold with a heater such as far infrared rays.
There is a method of charging the surface material with the surface material in the mold. Of course, press-molding only the backup material,
This may be integrated with the surface material by post-processing.

Next, as a third manufacturing method, a gap of 5 to 30 mm is provided in the male and female in-mold cavities when the backup material is molded. This method can be applied to the method described in the preceding paragraph, and the fiber-reinforced thermoplastic resin sheet
Although it depends on the amount of gas, a large amount of gas bubbles can be wound into the resin to form a bulky product, which provides a bathtub with excellent heat insulation and heat retention.

In such a production, a wooden mold may be used, or the product can be molded at a low pressure and has excellent productivity. At the time of disposal, the volume of the molded product is reduced to a very compact volume and the product is discarded. Or it can be recycled.

[0015]

According to the present invention, the entire matrix of the bathtub is made of a thermoplastic resin, and the surface material and the backup material are both made of a thermoplastic resin, and the backup material is made of glass fiber. Is used, so-called FRTP is used.

Various resins are conceivable as the thermoplastic resin material, and heat resistance, moldability, cost, appearance and the like are comprehensively judged before use. First, the resin as the surface material is an olefin such as polypropylene (PP) or polystyrene (P).
S), acrylonitrile butadiene styrene (AB
S), acrylonitrile-styrene (AS), polymethylmethacrylate (PMMA), acrylonitrile-ethylene-propylene-styrene (AES), polyacetate (POM) with excellent heat resistance, polybutylene terephthalate ( PBT), polyethylene terephthalate (PET), polycarbonate (PC), polyamide (PA), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), amorphous polyolefin (APO) (trade name APEL (Mitsui Sekiyu) (Chemical industry) etc.) and alloys or modified products thereof can be used. Especially when using the latter resin, which has excellent heat resistance of (ASTM-D-648) 100 ° C or more when the heat distortion temperature is a load of 18.6 kg / cm ² , install a circulation pot. Will also be possible.

Next, as the backup material, medium fibers (3 to 30 mm) or long fibers (30 mm or more) such as glass fibers are used in an amount of 10 to 5 with respect to 100% by weight of the thermoplastic resin.
A thermoplastic resin sheet (stampable sheet) containing 0% by weight, preferably 20 to 40% by weight, can be used.

In the present invention, a PP resin is preferably used, but of course the above-mentioned PS, ABS and modified PP are used.
O and the like can be used, and so-called engineering plastics such as PET, PBT, and PC can also be used, and the backup material has heat resistance.

The manufacturing method is mainly press molding, but in the case of blending medium fibers, deep drawing by vacuum forming or pressure forming is also possible. In addition, a gap is provided in the cavity,
Even when air bubbles are entrained and the molding is performed highly, it is preferable to mix and strengthen the medium fibers.

[0020]

【Example】

(Manufacturing Method 1) First, the present invention will be described with reference to an example of manufacturing a bathtub by a high pressure molding method. The outline of the manufacturing method is as shown in FIG. In the first step, a vacuum molded product A of amorphous polyolefin (APEL Mitsui Petrochemical Industry) sheet was prepared as the surface material of the bath. This preformed sheet A was inserted into a male mold 1 equipped with a hydraulic press, and the mold temperature was set to about 100 ° C. A stampable sheet in which long fibers are mixed as a backup material B (X sheet: PP resin (manufactured by Idemitsu Petrochemical))
Is heated in the far-infrared heater-3 in the second step, then put into the press, that is, on the sheet A, and quickly held by the female die 2 in the third step in the surface pressure of about 200 kg / cm ² . I squeezed. After cooling and solidifying for about 3 minutes, the molded product C was taken out.
When a PP-based stampable sheet is used as the backup material, an olefin-based material such as PP is a preferable combination because of its good adhesiveness as the surface material.

(Production Method 2) Next, an example of the production method by the low pressure method shown in FIG. 4 will be described. Now, in the first step, amorphous polyolefin (APEL
A vacuum molded product A of Mitsui Petrochemical Co., Ltd. sheet was prepared.
As a backup material B, a stampable sheet (Radlite: PP resin (manufactured by Marubeni Corporation)) containing medium fibers was used, and after heating with far infrared heater-3 in the second step, the entire circumference was heated. Clamp 4 was performed, and low-pressure molding (surface pressure of 30 kg / cm ² or less) was performed using male and female dies 1 and 2 in the third step to obtain a backup material B. After that, as a fourth step, the surface material A and the backup material B are integrated by using an adhesive,
Molded product C was produced.

In the third step, the male and female molds are wooden molds,
Either a resin type or an electroforming type may be used. Further, in the third step, the manufacturing method by pressing is shown, but it goes without saying that deep drawing to some extent (the depth with respect to the shortest diameter of the opening is 0.5 or less) is also possible by vacuum forming or pressure forming.

In the above manufacturing method, the surface material and the backup material are integrated with the same olefin. The selection of such a resin is effective for the adhesiveness of both and recycling. Also, as a surface material, 18.6k
When a so-called engineering plastic sheet having a heat distortion temperature of 100 ° C. or more under a load of g / cm ² is used, it is preferable to use the same sheet as a backup material in terms of adhesion. Dimensional accuracy is also improved.

(Manufacturing Method 3) Next, an example of manufacturing by a method of enclosing gas bubbles in the backup material will be described. The outline of this production method is shown in FIG. Now, in the first step, amorphous polyolefin (APEL
A vacuum molded product A of Mitsui Petrochemical Co., Ltd. sheet was prepared. This preformed sheet A was inserted into a male mold 1 equipped with a hydraulic press, and the mold temperature was set to about 100 ° C.

Next, a stampable seal containing a medium fiber
(Radlite: PP resin (manufactured by Marubeni Corp.)) is heated to 200 to 230 ° C. by far infrared heater-3 which is the second step, and this is put in the press, that is, on the sheet A. After holding the female die 2 in the third step, which is the mold clamping, as the fourth step, the upper die (female die 2) is temporarily raised by about 5 mm, and the thickness of the molded product is about 15 mm.
The position of the female mold 2 was set so that Mold temperature 100
Molded product C was taken out by cooling and solidifying at 3 ° C. for 3 minutes. The density of the obtained molded product C was about 1.0, a large amount of air bubbles were contained in the resin, and a bath having excellent heat insulating properties was obtained.

The means of manufacturing 3 may be arranged such that after the third step in manufacturing method 2, the upper mold is slightly displaced and gas bubbles are entrained in the backup material.

[0027]

As described above, the selection of the materials for the surface material and the backup material is determined by the manufacturing method (production amount) and performance thereof, and the thermoplastic surface material and the fiber-reinforced reinforced thermoplastic sheet are selected. By combining it as a backup material, it has boiling resistance as good as that of a conventional thermosetting resin in a bathtub, and can be sufficiently used as a bathtub attached to a circulating pot.

Also, since high productivity can be ensured by a cheap wooden mold or resin mold and several tens of pieces / day can be produced by one mold, it is not necessary to invest in a high mold or a high pressure press. Moreover, there are no crack defects that occur in FRP products as they are, and they are easy to handle because they have excellent impact resistance and strength. Further, by selecting various surface materials, various appearances can be obtained, which is preferable in terms of design. And above all, at the time of disposal, the volume can be reduced and recycling is possible unlike the conventional thermosetting resin.

[Brief description of drawings]

FIG. 1 is a sectional view of a molded bath C.

FIG. 2 shows a sectional view of a molded bath C.

FIG. 3 is a schematic view of manufacturing a bathtub by a high pressure molding method.

FIG. 4 is a schematic view of manufacturing a bathtub by a low pressure molding method.

FIG. 5 is a schematic view of manufacturing a bathtub by a method of enclosing gas bubbles in a backup material.

[Explanation of symbols]

 A: Surface material on the water bath side, B: Backup material, C: Bathtub, 1 ... Male type, 2 ... Female type, 3 ... Far infrared heater, 4 ... Clamp.

Claims (3)

[Claims] 1. The surface material on the water bath side is 18.6 kg / cm.
A bathtub made of a thermoplastic resin having a heat distortion temperature of at least 100 ° C. or more under a load of ² and using a fiber reinforced thermoplastic resin as a backup material, which are laminated and integrated. 2. A thermoplastic resin sheet and a fiber reinforced thermoplastic resin sheet are heated and softened, and then vacuum or pressure molded to form a surface material and a backup material separately, and then both are laminated and integrated. A method for manufacturing a thermoplastic resin bath, characterized by: 3. In the molding of the backup material, a density is 1.2 or less by forming a gap in the thickness direction of the backup material within a range of about 5 to 30 mm in the mold and entraining gas in the backup material. The thermoplastic resin bath according to claim 2, wherein the thermoplastic resin bath is produced by molding.