JP3318038B2 - Plastic plate manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention provides a method for easily producing a patterned plastic plate comprising an opaque plastic part and a transparent plastic part by a photopolymerization method as compared with the conventional method. Aim.

[0002]

2. Description of the Related Art Heretofore, a plastic patterned plate comprising a transparent portion and an opaque portion has been generally used in which an opaque resin is bonded to a transparent resin plate. JP-A-64-40946 describes a method for producing a patterned plastic plate from a composition comprising at least two types of photopolymerizable monomers or oligomers by using a special photopolymerization method.

[0003]

However, the method of laminating the transparent resin and the opaque resin has the disadvantages that the production process is complicated and waste material is generated.
The method described in Japanese Patent No. 4-40946 comprises a step of primary curing a mixture of an oligomer or a monomer using a special first light source, and a step of secondary curing using a second light source. It is necessary to use different light sources, and there is a difficulty in light source procurement.

[0004]

Means for Solving the Problems Accordingly, the inventors of the present invention have proposed 2
In order to develop a method for making a patterned plastic plate in an easier manner without using any kind of light source, a resin composition comprising the polymer (A) and the monomer (B) is homogeneous. It has been found that there is a temperature region where a transparent phase is formed and a temperature region where a phase is separated and an opaque phase is formed.By employing this phase transition phenomenon and photopolymerization, a patterned plastic plate without the above-mentioned difficulties can be obtained. Was found to be possible.

The gist of the present invention is to provide a resin composition comprising a polymer (A), a photopolymerizable monomer (B) and a photopolymerization initiator and having a transparent-opaque phase transition temperature. With a patterned mask applied to the plate-shaped imprint ,
A part of the plate-shaped imprint is polymerized by irradiation , and then, light is irradiated in a state where the mask is removed, and a method of manufacturing a plastic plate to polymerize an unpolymerized portion of the plate-shaped imprint , Plate-shaped imprint
Part of polymerization and one of unpolymerized polymerization
Perform the process at or above the phase transition temperature of the
And a monomer (B) photopolymerizable with the polymer (A)
And a photopolymerization initiator, and a transparent-opaque phase transition temperature
Phase transition temperature of a part of the plate-shaped shaped product of the resin composition
Temperature above and the other parts below the phase transition temperature
This is a method for producing a plastic plate , which is characterized by spray polymerization .

Accordingly, the present invention uses a single light source and
In one step, a plastic having a transparent-opaque pattern can be produced. Further, since the one-phase transparent phase and the opaque state of the two-phase separation can be reversibly changed by causing a temperature change of the resin composition, the temperature of each part of the resin composition before curing is reduced. controlled, if desired the resin composition in a transparent state or photopolymerized by applying a mask having a pattern with an opaque state, further in a state in which the phases change of the resin composition, photopolymerizing with the exception of the mask Plastic plate having the following pattern. As another method, the plate-shaped resin composition is partially heated to a temperature lower than the phase transition temperature to form an opaque portion, and the other portion is heated to a temperature higher than the phase transition temperature to form a transparent portion. By performing photopolymerization in a state where a pattern is formed in the plate, a patterned plastic plate intended for the present invention can be obtained.

The polymer (A) used in carrying out the present invention includes, for example, acrylic polymers such as polymethyl methacrylate, polystyrene and its derivatives, and polyhalogenated olefins such as polyvinylidene fluoride. However, the present invention is not limited to these. Naturally, a homopolymer or a copolymer can be used, and one or a combination of two or more can be used. These polymers (A) should be selected so that the purpose of use, particularly the phase transition phenomenon of the resin composition combined with the monomer, can be efficiently utilized.

The photopolymerizable monomer (B) used in carrying out the present invention is, for example, an acrylic monomer such as methyl methacrylate, styrene and its derivatives, or an acryloyl group or a methacryloyl group in the molecule. A monomer having at least one kind of vinyl group, allyl group, or two or more groups can be used. These monomers should be selected so as to sufficiently achieve the object of the present invention in combination with the polymer (A).

The photopolymerization initiator (C) used in the present invention may be a commonly used one, such as benzophenone, Michler's ketone, 2-chlorothioxanthone, benzoin ethyl ether, diethoxyacetophenone, benzyldimethyl ketal, Hydroxy-2-methylpropiophenone, 1-hydroxycyclohexylphenyl ketone and the like can be mentioned.

As a light source used for photopolymerization, an ordinary light source can be used. For example, an ultrahigh-pressure mercury lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a chemical lamp, or a light obtained by converting light from these light sources into parallel light through a collimating lens.

In order to photopolymerize the composition of the polymer (A) and the monomer (B) using these light sources, the polymerization is carried out in order to avoid contact with oxygen which inhibits the polymerization of these compositions. It is preferable to use a method in which the surface of the excipient of the coalesced composition is placed under a nitrogen atmosphere, or a photopolymerization is performed by covering the surface of the excipient of the polymer composition with a polyester film, and the polymer composition is cured. . The phase transition temperature of the polymer composition can be adjusted by changing the composition of the polymer solution composed of the polymer (A) and the photopolymerizable monomer (B) used in the present invention. . The lower the compatibility between the polymer (A) and the polymer of the monomer (B) used in the present invention, the better the compatibility of the resin composition used as the raw material, even if the compatibility is good. Of the polymer (A) in the resin composition
By increasing the content of the resin composition and increasing the viscosity of the resin composition, phase separation hardly occurs, and the transparency of the resin composition after curing can be improved.

According to the patterned plastic plate of the present invention, a desired patterned plate can be freely formed by a simple manufacturing method and by freely changing the shape of the photomask.
It can be usefully used as a window glass, a signboard, and the like.

Hereinafter, the present invention will be described in more detail with reference to examples.

[0014]

Example 1 A resin composition comprising 70 parts by weight of polystyrene (polymerization degree: 1600 to 1800), 30 parts by weight of methyl methacrylate, and 0.5 part by weight of 1-hydroxycyclohexyl phenyl ketone was covered with a polyester film, and a plate having a thickness of 500 μm was prepared. It was shaped into a shape. This polymer solution was transparent at 25 ° C. in a one-phase compatible state. A photomask as shown in FIG. 1 was applied to the surface of the plate-like shaped object, and ultraviolet light (irradiation intensity: 400 mW / cm ² ) from a metal halide lamp was irradiated from the upper surface for 5 minutes. The resulting resin composition became a transparent cured portion. Next, the photomask was removed, the resin composition was cooled to 10 ° C., and the uncured portion was turned into a two-phase opaque portion, and irradiated with ultraviolet light for 5 minutes in the same manner as described above. The resulting plastic plate was obtained.

[0015]

Example 2 Only the central portion of the resin composition formed into a plate having a thickness of 500 μm used in Example 1 was cooled to 10 ° C. or less to make it opaque, and the other portions were kept at 25 ° C. When the transparent portion was irradiated with ultraviolet light (irradiation intensity: 400 mW / cm ² ) from a metal halide lamp for 5 minutes, the cooling portion at the center became white, and the other portions became transparent and hardened. A pattern plate having an opaque pattern was obtained.

[0016]

Example 3 Polymethyl methacrylate (Acrypet
VH; manufactured by Mitsubishi Rayon Co., Ltd.) 40 parts by weight, methyl methacrylate 10 parts by weight, t-butyl methacrylate 50 parts by weight, 1-
A resin composition consisting of 0.5 parts by weight of hydroxycyclohexyl phenyl ketone is covered with a polyester film and has a thickness of
It was shaped into a 500 μm plate. The central portion of the plate-shaped resin composition was circularly maintained at 25 ° C. to form an opaque portion in a two-phase-separated state, and the other portion was maintained at 70 ° C. to form a transparent portion. Strength 400mW / cm ² )
Was irradiated for 5 minutes, the center became a circular transparent part, and the other parts were hardened to white to obtain a plate-like body having a transparent-opaque pattern.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a photomask used in carrying out the present invention.

[Explanation of symbols]

 1 ...... Transparent part 2 ...... Light opaque part

────────────────────────────────────────────────── (5) References JP-A-64-40903 (JP, A) JP-A-64-40946 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02B 5/00 G02B 5/02

Claims (2)

(57) [Claims] 1. A plate-shaped imprint of a resin composition comprising a polymer (A), a photopolymerizable monomer (B) and a photopolymerization initiator and having a transparent-opaque phase transition temperature. in engaged condition where masked, polymerizing a portion of the plate-like shaping product by light irradiation, and then irradiated with light in a state excluding the mask manufacturing method of the plastic plate polymerizing the unpolymerized portions of the plate-like shaping product
The polymerization of a part of the plate-shaped excipient and the polymerization of an unpolymerized product
One of the polymerization is carried out above the phase transition temperature of the resin composition, the other
Plasticizer, which is performed at a temperature lower than the phase transition temperature .
Manufacturing method of plate . 2. A monomer capable of photopolymerization with the polymer (A)
(B) and a photopolymerization initiator, a transparent-opaque phase
Inversion of a part of the plate-shaped molded product of the resin composition having a transition temperature
Temperature above the transition temperature and the other parts below the phase transition temperature.
Plastic plate characterized by being irradiated with light and polymerized
Recipe.