JP2837129B2 - Forming method of polyvinyl chloride plate or polycarbonate plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for heat-forming a polyvinyl chloride (PVC) plate or a polycarbonate plate.

[0002]

2. Description of the Related Art A thermoplastic plastic plate according to the present invention comprises:
For example, it is for producing a relatively small decorative panel used for home electric appliances, industrial machinery and the like. Conventionally,
Such a molding method of a plastic plate is roughly classified into molding methods as shown in FIGS.

The molding method shown in FIG. 6 is a method in which a plastic plate 32 at normal temperature is sandwiched between a heated upper die 30 and a lower die 31 of a molding machine to form a desired shape. On the other hand, the molding method of FIG. 7 is a method in which a plastic plate 33 heated and softened in advance is sandwiched between an unheated upper mold 34 and a lower mold 34 and cooled to mold into a desired predetermined shape.

[0004]

However, in the above-mentioned conventional molding method, the finished product is liable to be distorted or twisted. For example, if a plastic plate 32 or 33 molded into a bowl shape is placed face down on a flat object, the peripheral portion 36 is partially lifted and rattled, and has no value as a product. As described above, the conventional molding method has a large variation in the quality of the product and the yield is poor. Further, the conventional molding method requires a molding machine and other large-sized equipment, and thus has a disadvantage that the product cost is increased accordingly.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and the resulting product has little distortion and twist, is stable in quality, has a good yield, and can be manufactured at low cost. It is an object of the present invention to provide a method for forming a plate.

[0006]

SUMMARY OF THE INVENTION The polyvinyl chloride of the present invention
Molding process of the plate, after placing the thermoplastic polyvinyl chloride plate type material formed in a shape of interest, 70 ° C. to 80 ° C.
The polyvinyl chloride plate is heated and softened at a temperature of 30 minutes to 40 minutes , and the softened polyvinyl chloride plate is formed by its own weight along the shape of the mold. In addition, the polycarbonate of the present invention
Molding process of site plate is, after placing the thermoplastic polycarbonate plate type material formed in a shape of interest, 120 ° C.
Polycarbonate at a temperature of ~ 160 ° C for 50 ~ 60 minutes
The softened polycarbonate plate is heated and softened, and the softened polycarbonate plate is formed by its own weight along the shape of the mold.

[0007] A polyvinyl chloride plate or po
The polycarbonate plate cannot maintain its original shape due to its own weight, and deforms along the profile. After being completely deformed along the shape, when it is returned to room temperature,
A vinyl chloride plate or a polycarbonate plate is formed into a shape of a mold.

[0008]

[0009]

[0010]

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a process chart showing a molding method according to the first embodiment of the present invention. In FIG. 1 (A), reference numeral 1 denotes a molding die, on which an aluminum corrugated plate 3 is welded on an aluminum substrate 2.
Aluminum is used because of its good thermal conductivity. However, copper, iron, or other materials may be used as long as they can withstand the heating temperature.

Reference numeral 4 denotes a plastic plate for molding.
It is made of VC, polycarbonate, polyester, nylon, acrylic, or the like, but is not limited to such a plastic as long as it is a thermoplastic resin. Characters and patterns are printed on the surface of the plastic plate 4, and depending on the object, a protective film (not shown) is further provided on the front and back surfaces.
Is attached.

The plastic plate 4 is placed on the mold 1 as shown in FIG. 1B and heated. The heating temperature and heating time are
Determined according to the plastic plate 4. For example, in the case of PVC, it is heated at a temperature of 70 ° C to 80 ° C for 30 to 40 minutes, and in the case of polycarbonate at 120 ° C to 160 ° C,
Heat for 50-60 minutes. In addition, the heating temperature and time are adjusted in consideration of the thickness and size of the plastic plate.

As described above, when the plastic plate 4 is heated at the determined temperature and time, the plastic plate 4 reaches the softening point and bends along the corrugated plate 3 by its own weight as shown in FIG. 1C. . After the plastic plate 4 is completely bent, it is carried out of the heater, left in the air and cooled to complete the molding.

FIG. 2 shows a second embodiment of the present invention, which is a modification of the first embodiment. The second embodiment shows a case where the plastic plate 4 is formed in a curved shape. The mold 5 of this embodiment has a curved plate 7 mounted on an aluminum substrate 6. The curved plate 7 has two rectangular cutouts 8 in the longitudinal direction, and a backing plate 9 is attached from the back surface, and the surfaces of the central portion 10 and both side portions 11 in the longitudinal direction project from the surface of the backing plate 9. With such a configuration, even if the ink printed by forming a gap between the back surface of the plastic plate 4 and the surface of the backing plate 9 is softened by heat during molding, it adheres to the curved plate 7 and printing is performed. I keep it clean.

In addition, locking plates 12 are attached to both ends of the molding 5 in the longitudinal direction, and both ends of the plastic plate 4 are locked to the locking plates 12 and heated. The heating temperature and time
It is determined according to the plastic plate 4 in the same manner as in the first embodiment.

The feature of the second embodiment is that the plastic plate 4 is fixed before heating, so that more accurate molding can be performed. FIG. 3 is a perspective view showing one step of the molding method according to the third embodiment of the present invention. This third
In the embodiment, a three-dimensional curved surface (the outer peripheral edge of the plastic plate 4 is bent in a certain manner to form a three-dimensional shape)
A method of forming a two-dimensional curved surface (the plastic plate 4 is bent in either the longitudinal direction or the width direction) as in the first and second embodiments. Are different.

The jig used in the third embodiment comprises a mold 13 and a holding plate 14. The molding 13 is
On an aluminum substrate 15, a projection 16 corresponding to a shape to be molded of a product is attached. If the plastic plate 4 has a hole 17, a projection 18 is provided on the projection 16.

The holding plate 14 is made of an aluminum plate and has a hollow 19 for holding the outer periphery of the plastic plate 4. The shape of the holding plate 14 changes according to the desired shape of the plastic plate 4.

Next, the molding procedure will be described with reference to FIG.
FIG. 4A shows a state before the plastic plate 4 is sandwiched between the mold 13 and the pressing plate 14. And FIG.
As shown in (B), the plastic plate 4 is sandwiched between the mold 13 and the holding plate 14 and fixed by the clip 20. Although the clip 20 is simple and convenient to pinch, the present invention is not limited to such a clip 20 as a tool for pinching, and any means capable of pinching may be used.

In the case of heating as shown in FIG. 4 (C), a large number of the set plastic plates 4 are placed on a carriage 22 having a plurality of shelves 21 as shown in FIG. Process all at once.

The heating temperature is set to P, as in the first embodiment.
In the case of VC, it is heated between 70 ° C to 80 ° C for 30 to 40 minutes, and in the case of polycarbonate, it is 120 ° C to 160 ° C.
And heat for 50-60 minutes.

When heated at a predetermined temperature for a predetermined time, the outer peripheral edge of the plastic plate 4 is
Can be bent dimensionally. However, the method according to the third embodiment can be bent two-dimensionally or partially besides three-dimensionally by changing the shape 13 and the holding plate 14.

After a predetermined time has passed and the plastic plate 4 has been completely bent, the plastic plate 4 is taken out from the heater 22 and cooled, the clip 20 is removed, and the mold 13 and the holding member 13 are pressed as shown in FIG. The molding is completed when the plate 14 is removed.

According to this molding method, uniform molding with almost no deformation or distortion can be achieved by a simple method. In particular, the plastic plate 4 after the heat molding does not cause springback, and a substantially complete product can be manufactured. Moreover,
Since a mold member and a holding plate can be manufactured at low cost, the manufacturing cost is reduced as compared with a conventional method using a mold.

[0026]

According to the present invention, the above structure
With a relatively simple method, it is possible to form a uniform plastic plate with almost no deformation or distortion, and the quality is stable, the yield is improved, and the production can be performed at low cost.

[Brief description of the drawings]

FIG. 1 is a process chart of a first embodiment of a molding method according to the present invention.

FIG. 2 is a process chart of a second embodiment of the molding method of the present invention.

FIG. 3 is a perspective view of one step of a third embodiment of the molding method of the present invention.

FIG. 4 is a process chart of a third embodiment of the molding method of the present invention.

FIG. 5 is a schematic view of a heating step of the molding method of the present invention.

FIG. 6 is a schematic view of a conventional molding method.

FIG. 7 is a schematic view of a conventional molding method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold material 4 Plastic plate 5 Mold material 12 Locking plate 13 Mold material 14 Holding plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B29C 51/02-51/24 B29C 51/30-51/42 B29K 27:06 B29K 69:00

Claims (5)

(57) [Claims] 1. After placing a thermoplastic polyvinyl chloride plate on a mold formed in a desired shape, the mold is heated to 70 ° C. to 80 ° C.
And heating the polyvinyl chloride plates 30 to 40 minutes at a temperature to soften, polyvinyl chloride, which comprises molding along a shape of the mold member by its own weight and softened polyvinyl chloride plate
Plate forming method. 2. After a thermoplastic polycarbonate plate is placed on a mold formed in a desired shape, the temperature is set to 120 ° C. to 16 ° C.
At 0 ℃ temperature, port, characterized in that softened by heating the polycarbonate plate 50 to 60 minutes, it is molded along a shape of the mold member by its own weight the softened polycarbonate plate
A method of forming a carbonate plate . 3. A two-dimensional curved surface is formed on a locking portion provided on a mold member.
3. The polyvinyl chloride plate according to claim 1, wherein after the peripheral portion of the bent plate is locked, the plate is heated and softened.
Alternatively, a method for forming a polycarbonate plate . 4. The shape material has a hollow, and a backing plate is provided on the back surface.
Attached to the back of a plate bent into a two-dimensional curved surface
4. A gap between the plate and the surface of the plate.
Forming the described polyvinyl chloride plate or polycarbonate plate
Method. 5. A method of pressing a plate with a pressing plate for pressing an outer peripheral portion thereof , heating and softening the plate, and forcibly shaping the plate into a three-dimensional curved surface according to the shape of the mold material by the pressing plate. 3. Polyvinyl chloride according to claim 1 or 2,
Forming method of plate or polycarbonate plate .