JPH06143308A - Manufacture of resin plate - Google Patents

Abstract

(57) [Summary] [Problem] To provide a copolymer molded plate of a maleimide compound, which can be easily peeled from a mold without using a release agent and has excellent surface smoothness and other surface characteristics. [Structure] A resin prepared by polymerizing a monomer mixture containing a maleimide compound in a mold to form a resin plate, using a glass plate having a functional film of an inorganic compound on the surface as a resin plate forming mold. Method of manufacturing a plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a resin plate from a monomer mixture containing a maleimide compound, and more specifically, a functional film made of an inorganic compound is surface-treated as a resin plate molding mold. The present invention relates to a method for producing a resin plate having excellent surface smoothness and various surface characteristics by using the glass plate of 1.

[0002]

2. Description of the Related Art When a maleimide monomer is polymerized alone, a polymer having high heat resistance can be obtained. By utilizing this characteristic, it is possible to obtain a polymer which can be copolymerized with other vinyl monomers to improve the heat resistance of the vinyl polymer, and which can also be used for optical applications.

Molding of a resin plate, for example, casting in which a polymerization-reactive monomer is injected into a cell made of two glass plates and a flexible gasket, polymerized and cured, and the cell is disassembled to take out the plate. The method is well known,
Acrylic plates and polydiethylene glycol bisallyl carbonate plates with good appearance quality have already been industrially produced (for example, JP-A-62-264914). At the time of this production, soda lime glass formed by the float method is used, but since there is no adhesion between the glass and the resin plate, the plate can be easily taken out after the completion of the polymerization.

[0004]

However, when a vinyl monomer is mixed with, for example, styrene, methylmethacrylate, etc. and a maleimide monomer, a resin plate having good heat resistance, particularly a transparent resin plate, is obtained when soda lime glass is used. When used for molding, it adheres strongly to the glass surface, and good appearance characteristics cannot be obtained. This tendency increases as the added amount of the maleimide compound increases.

As a means for solving this problem, it is possible to add a release agent internally or coat it on the glass surface, but a layer rich in release agent can be formed on the surface, and printing, coating, adhesion However, some problems will occur in the subsequent process.

Therefore, an object of the present invention is to provide a maleimide compound copolymer molded plate which can be easily peeled from a mold without using a release agent and which is excellent in surface smoothness and other surface characteristics. It is about the manufacturing method for doing.

The present invention relates to a molding die for molding by a casting method in which a maleimide type monomer alone or a mixture with another vinyl monomer is injected into a die and polymerized.

[0008]

According to the present invention, when a monomer mixture containing a maleimide compound is polymerized in a mold to mold a resin plate, a functional film made of an inorganic compound is used as a resin plate molding mold. Provided is a method for producing a resin plate, which comprises molding using a glass plate having a resin on its surface.

As the functional film of an inorganic compound, for example,
An oxide thin film such as TiO ₂ or Al ₂ O ₃ , an antireflection thin film such as MgF or CaF, and a conductive thin film such as tin oxide or tin oxide-antimony oxide (ITO) are used. It is not limited to the example of.

[0010]

In the present invention, the glass plate is used as the mold for molding the above-mentioned monomer mixture because the glass plate, especially the glass plate by the float method is a relatively inexpensive material having the best smoothness. However, when a maleimide monomer-containing mixture is charged in a glass plate as a mold and molded by polymerization, as already pointed out, the resin-molded plate firmly adheres to the glass plate and its peeling becomes difficult. Not only that, there is a drawback that a resin molded plate having an excellent surface smoothness cannot be obtained.

In order to solve this problem, the present invention is characterized in that an inorganic functional film is formed in advance on the glass plate prior to the polymerization and molding of the monomer mixture. This inorganic functional film prevents the resin to be polymerized from adhering to the glass plate and acts to promote the separation between the resin plate and the glass plate, and since this functional film is an inorganic material, Unlike the conventional release agents, it does not impede printing, coating, adhesion, etc. applied to the molding plate afterwards.

Thus, according to the present invention, there are advantages that the surface smoothness of the maleimide resin plate can be improved and the surface characteristics can be improved, and the workability in the manufacturing process can be improved. Further, since the inorganic functional film formed on the glass plate may be a very thin film as described later, there is an advantage that the operation is simple and the cost is relatively low.

[0013]

Preferred Embodiment of the Invention

(Monomer Mixture) The maleimide monomer used in the present invention is known per se, and any known one can be used. This monomer may be a monofunctional one or a difunctional or higher polyfunctional one, but a monofunctional one is preferable in terms of optical properties, and a polyfunctional one in terms of heat resistance. Is advantageous.

Suitable examples of maleimides include those of the general formula

[Chemical 1] (Wherein R ₁ and R ₂ represent a hydrogen atom, a halogen atom or a methyl group, and R ₃ represents an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group or an aryl group), and a general formula

[0015]

[Chemical 2] (In the formula, R ₁ and R ₂ have the above-mentioned meanings, and R ₄ represents an alkylene group having 2 to 18 carbon atoms, a cycloalkylene group, an arylene group or a combination thereof.)
It is a maleimide compound represented by.

Specific examples include N-methylmaleimide, N
-Ethylmaleimide, N-cyclohexylmaleimide,
N-phenylmaleimide, N-benzylmaleimide,
N, N '-(xylylene) bismaleimide, N, N'-
(Ethylene) bismaleimide, N, N '-(phenylene) bismaleimide, N, N'-(propylidene-p-
Diphenylene) bismaleimide and the like.

In the present invention, as the other monomer used in combination with the maleimide monomer, any α-β ethylenically unsaturated monomer such as styrene,
Aromatic vinyl monomers such as vinyltoluene; methacrylic acid, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, acrylic acid, methyl acrylate, acrylic acid (Meth) acrylic monomers such as ethyl, butyl acrylate, 2-ethylhexyl acrylate, and lauryl acrylate; and monomers having two or more reactive groups in the molecule; for example, divinylbenzene, dimethacrylic acid. Ethylene glycol, 1,3-butylene dimethacrylate glycolate, trimethylolpropane trimethacrylate,
Examples thereof include allyl methacrylate, diallyl phthalate, diethylene glycol bisallyl carbonate and the like. Among these, styrene and (meth) acrylic acid ester are preferable.

The monomer mixture used in the present invention contains 10 to 80 maleimide monomers per monomer mixture.
It is preferable to use it in an amount of 30% by weight, especially 30 to 70% by weight, and even in such a large amount. It is a remarkable feature that it can be easily peeled from the glass plate. When the amount of the maleimide monomer used is lower than the above range, the improvement of heat resistance and optical properties is insufficient, and even when the amount is more than the above range, there is no particular advantage, and it is economically disadvantageous. The mechanical properties of the plate will rather deteriorate.

In order to carry out the polymerization, the maleimide monomer mixture contains radical initiators known per se, for example, azo compounds such as azobisisobutyronitrile, lauryl peroxide, acetyl peroxide and benzoyl peroxide. Oxide, t-butyl peroxypivalate, t-butyl peroxy neodecanoate,
An organic peroxide such as t-butyl peroxyoctoate or diisopropyl peroxydicarbonate is added.
One or two or more of these initiators are blended in a catalytic amount, generally in the range of 0.1 to 2% by weight, based on the monomer mixture.

In the monomer mixture used in the present invention,
It is also possible to mix any known compounding agent, for example, various additives such as a viscosity modifier, a surfactant, a dispersant, a release agent, a colorant and a filler. For example, for applications other than optical applications, for example, talc, silica, calcium silicate, hydrated aluminum, alumina, calcium carbonate, magnesium hydroxide, etc. can be used. These inorganic fillers are used in an amount of 1 per 100 parts by weight of the above-mentioned curable resin component.
It is preferably used in an amount of 00 to 300 parts by weight.

(Mold for Molding Resin Plate) In the present invention, a glass plate having an inorganic functional film formed on its surface is used.
As the glass plate, soda lime glass formed by the float method is advantageously used from the viewpoint of surface smoothness and economy.

As the inorganic functional film, titanium oxide (T
iO ₂ ), alumina (Al ₂ O ₃ ), silicon oxide (Si
O, SiO ₂ ), zirconium oxide (ZrO ₂ ), tin oxide (SnO ₂ ), tin oxide-antimony oxide (ITO)
And oxides such as MgF ₂ and CaF ₂ and nitrides such as aluminum nitride and silicon nitride.

The inorganic functional film can achieve a sufficient function even if it is very thin, and its thickness is generally 500 to 5000.
Angstroms, especially in the range 1000 to 3000 Angstroms are sufficient.

The inorganic functional film can be formed according to a known thin film forming technique such as sputtering, vacuum deposition, CVD (chemical vapor deposition) or the like. For example, in the case of sputtering, a composition having a composition close to the above composition (for example, a sintered body) is used as a target, and sputtering is performed in an inert gas such as argon. Of course, reactive sputtering is also possible.

The above-mentioned coated article can obtain the same effect, but since the TiO ₂ coated glass is commercially available as a window glass for construction for heat ray reflection, it is particularly useful because it is easily available.

(Polymerization Molding) According to the present invention, the monomer mixture is poured into a cell made of two glass plates each having a glass surface coated with an inorganic functional film, and the mixture is heated and polymerized and cured. The molded product can be easily taken out by cooling it and driving a wedge between these glass plates, for example.

In the production method of the present invention, between the two glass plates, a string-shaped or frame-shaped molded product of a resin having a cushioning property between the edges is interposed as a spacer, and the monomer composition is contained therein. It is preferable to inject and heat-polymerize.

The polymerization reaction is preferably carried out at a high temperature so that no strain remains in the resin plate formed by the polymerization. Generally, this reaction is 60 to 200 ° C, particularly 130 to 200 ° C.
Is preferably carried out at a temperature of. It is also effective for relaxing strain that the temperature is raised during the polymerization and the final stage polymerization is carried out at a higher temperature.

[0029]

The present invention will be further described in the following examples. Example 1 (Preparation of coating glass) TiO ₂ , Al ₂ O ₃ was added to soda lime glass molded by the float method with a thickness of 8 mm.
Was coated by sputtering to a film thickness of 2000A. (Creation of glass cell) A cell with the coated glass 2 plate made above, the inner surface of which is the coating surface, and a 1.1 mm thick soft PVC square string set around the clearance and clamped to have a clearance of 1.1 mm. It was created.
As a comparison, cells were also prepared at the same time on uncoated glass.

(Preparation of Maleimide Copolymer Plate) Azobisisobutyronitrile 0.3% was added to the mixture having the composition shown in Table 1.
After adding and dissolving wt%, the mixture was poured into the cell prepared above, and the temperature was 70 ° C. for 1 hr, 70 → 150 ° C. for 2 hr, 150 ° C. 2
The monomer in the cell was cured by polymerization for hr. Regarding the adhesion to the mold, a brass wedge was driven into the gap between the two glasses at 80 ° C., and the following three-stage evaluation was performed. ◯: A plate can be molded without any adhesion and with no appearance defect. △: The plate can be taken out, but a white mark that seems to have come off is left on the surface of the plate. X: The adhesion is too strong and the glass or plate is broken.

[0031]

[Table 1]

Example 2 In Example 1 above, M was used as the coating glass.
In the same manner as in Example 1, except that gF23000 angstrom coated with vacuum deposition was used,
A maleimide-based copolymer plate was manufactured. The peeling from the glass plate was good and the surface smoothness was also excellent.

Example 3 In Example 1 above, the coating glass was I
Example 1 except that 1700 angstroms of TO coated with sputtering was used.
A maleimide-based copolymer plate was produced in the same manner as in. The peeling from the glass plate was good and the surface smoothness was also excellent.

[0034]

According to the present invention, when a resin mixture is molded by polymerizing a monomer mixture containing a maleimide compound in a mold, a functional film of an inorganic compound is provided on the surface as a resin plate molding mold. Molding with a glass plate facilitates peeling from the mold without using a release agent, and provides a maleimide compound copolymer molded plate excellent in surface smoothness and other surface characteristics. I was able to.

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[Procedure amendment]

[Submission date] November 11, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

As the inorganic functional film, titanium oxide (T
iO ₂ ), alumina (Al ₂ O ₃ ), silicon oxide (Si
O, SiO ₂ ), zirconium oxide (ZrO ₂ ), tin oxide (SnO ₂ ), tin oxide-antimony oxide (ITO)
And the like, fluorides such as MgF ₂ and CaF ₂ , and nitrides such as aluminum nitride, silicon nitride, and titanium nitride.

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Claims (4)

[Claims] 1. When polymerizing a monomer mixture containing a maleimide compound in a mold to mold a resin plate, a glass plate having a functional film of an inorganic compound on its surface is used as a resin plate molding mold. A method for manufacturing a resin plate, which comprises: 2. The method for producing a resin plate according to claim 1, wherein the functional film of the inorganic compound is a thin film of TiO ₂ or Al ₂ O ₃ . 3. The method for producing a resin plate according to claim 1, wherein the functional film of an inorganic compound is a thin film of MgF or CaF. 4. The method for producing a resin plate according to claim 1, wherein the functional film of the inorganic compound is a thin film of tin oxide or tin oxide-antimony oxide (ITO).