JPH06190842A - Sheet manufacturing method - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to form a sheet from a highly viscous syrup into a plate-like object of any width without using a sealing material, and to easily and economically produce a sheet. Provide a way you can. [Structure] In the method for producing a sheet in which a syrup containing a polymer is supplied and shaped into a plate with a roll, a high-viscosity syrup containing a polymer is supplied in a rod shape, and is forcibly rolled with a roll, By forming the
It is characterized in that the width is controlled by the flow rate to form a plate shape.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a sheet,
Particularly, it relates to a method for producing a sheet in which a polymer syrup containing methyl methacrylate as a main component is shaped into a plate.

[0002]

2. Description of the Related Art As a method for shaping a polymer into a plate,
A relatively low-viscosity syrup containing a polymer is enclosed in a space formed by a rotating belt arranged so as to face up and down and a sealing material sandwiched between the belts on both sides of the rotating belt, and shaped. The method of doing so is disclosed in Japanese Examined Patent Publication Nos. 46-41602, 47-34815 and 52-30985.

[0003]

However, in such a method, since the polymerization rate of the low-viscosity syrup is low, the polymerization time is long, the polymerization apparatus becomes large, and the sealing material is indispensable for setting the width. There was a problem. On the other hand, a method in which a syrup containing a polymer is extruded from a die and shaped into a plate is also disclosed in JP-A-4-146903. This method is advantageous in that it forms a high-viscosity syrup, but since a die is used, the die replacement work and the cleaning work when the colored plates are sold out are complicated and take a long time. Further, there is a drawback that the polymerization proceeds until the polymerization reaction product is pushed out from the die, and the flow path inside the die is blocked.

In order to solve the problems of these conventional methods, the inventor of the present invention can form a highly viscous syrup into a plate-like object of any width without using a sealing material. As a result of studies for providing a method capable of economically producing a sheet, the present invention has been completed.

[0005]

According to the present invention, in order to solve the above-mentioned problems, a syrup containing a polymer is supplied, and a polymer is contained in a process for producing a sheet which is shaped into a plate by a roll. A sheet manufacturing method characterized in that a high-viscosity syrup is supplied in a rod shape, forcibly rolled by rolls, spread in the width direction by forming a bank, the width is controlled by the flow rate, and shaped into a plate shape. Will be provided.

That is, according to the method of the present invention, a highly viscous syrup (500 to 50000 poise) containing a polymer is fed in a rod shape by a pipe without using a die and is forcibly rolled by a roll to form a bank. By forming it, it is widened in the width direction, the width is controlled by the flow rate, and shaped into a plate. The syrup used in the method of the present invention contains, as a monomer, methyl methacrylate alone or a monomer mixture containing methyl methacrylate as a main component, and a polymer of the monomer as a polymer. In the case of the monomer mixture, methyl methacrylate is preferably 80% by weight or more. Examples of the monomer used together with methyl methacrylate include ethyl methacrylate, propyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, methacrylic acid esters such as benzyl methacrylate, methyl acrylate, and acrylic acid. Examples thereof include acrylic acid esters such as ethyl acidate, butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate and benzyl acrylate, styrene, α-methylstyrene and the like.

As the polymerization initiator of the above-mentioned monomer, a radical polymerization aid such as di-isopropyl peroxydicarbonate, tert-butyl neodecanoate, tert-
Butyl peroxypivalate, lauroyl peroxide, benzoyl peroxide, tert-butyl peroxyisopropyl carbonate, tert-butyl peroxybenzoate, dicumyl peroxide, organic peroxides such as di-tert-butyl peroxide, 2, 2-azobis (2,4-dimethylvaleronitrile), 2,2-azobisisobutyronitrile, 1,1-azobis (1-cyclohexanecarbonitrile), 2,2-azobis (2,2
4,4-trimethylpentane) and other azo compounds.

In addition, if necessary, a molecular weight modifier may be used. Specifically, a primary, secondary or tertiary mercaptan having an alkyl group or a substituted alkyl group, for example, n-butyl mercaptan, iso-butyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, sec- Butyl mercaptan, sec−
Examples include dodecyl mercaptan and tert-butyl mercaptan.

Further, various additives such as an oxidation stabilizer, a plasticizer, a dye, a pigment and a release agent may be added as required. The amount of the polymerization initiator used is appropriately determined depending on the polymerization temperature and the intended polymer conversion rate, but is usually 0.01 to 2% by weight with respect to the monomer mixture. Supplied from a pipe syrup in which a polymerization initiator and the like are inversion mixed, is forcibly rolled by a roll, spreads in the width direction by forming a bank, and is shaped into a plate, the viscosity of the syrup supplied is , Depending on the degree of polymerization, at least 500 pois
It is preferably e. From the viewpoint of productivity, the polymer content of the syrup to be supplied is usually preferably 40% by weight or more.

Preferred embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, two endless belts 3 and 3'arranged vertically are driven by the main drums 4, 5, 4 ', and 5'to be tensioned and run at the same speed. Roller group 6 paired up and down,
The 6'supports the endless belt running horizontally and regulates the thickness of the polymerized compound. The syrup is sent by the metering pump 1 and is fed to the belt by the feed pipe 2. The syrup completes the heat polymerization with the hot water sprays 7 and 7'as the belt runs, and the plate-shaped product 8 is taken out.

In the present invention, the syrup containing a polymer having a high viscosity of 500 to 50,000 poise is effectively used for plate-shaped shaping, and a syrup containing a polymerization initiator and necessary additives is mixed with a feed pipe. It is supplied to the endless belt 3'from No. 2 and transferred. Here, when the belt and the syrup are in contact with each other, it is preferable that the supply shape of the syrup is a cylindrical shape in order to prevent the entrapment of air bubbles.

With the running of the belt, the syrup comes into contact with the main drum 4 and is rolled, and spreads in the width direction while forming the bank 9. The thickness after shaping the syrup is the upper and lower belts 3, 3 '
Since the width is controlled by the syrup supply amount at the intervals of, the width can be easily changed with the syrup supply amount while keeping the thickness constant. Therefore, if necessary, a sealing material intended to prevent the mixing of water and foreign matter between the belts during polymerization can be supplied between the belts 3 and 3 ', and the width can be changed within the range between the sealing materials. Is.

The plate-shaped syrup has belts 3 and 3 '.
It moves while being sandwiched between them, and heat polymerization is completed. In addition,
The size of the bank can be estimated from the relationship among the syrup viscosity, the belt drum diameter, the belt speed, the plate thickness, and the plate width. It is also possible to supply syrup to the peripheral surface or from the upper part of two vertically arranged endless belts. Further, since the syrup has a high viscosity (high polymerization rate), the polymerization time is shortened, so that the belt device can be shortened.

[0014]

The present invention will be described in more detail with reference to the following examples. Example 1 Methyl methacrylate syrup having a viscosity of 5000 poise (polymer content of 40%) was supplied to a lower belt with a width of 30 mm from a pipe having an inner diameter of 30 mm, and was moved at a belt speed of 0.11 m / min, and a belt interval was set to 3 mm. Rolled with an upper belt drum to form a bank, spread the syrup in the width direction, shape it into a plate shape, heat the belt with warm water, and proceed with the polymerization of the syrup sandwiched between the belts, so that the polymer content is 90%. did.

This plate-shaped sheet has a plate thickness of 3 ±
The thickness was 0.1 mm and the thickness was excellent, and the width was 400 mm and the appearance was good. Example 2 Methyl methacrylate syrup having a viscosity of 2400 poise (polymer content of 40%) was supplied to a lower belt with a width of 30 mm from a pipe having an inner diameter of 30 mm, the belt was moved at a belt speed of 0.22 m / min, and a belt interval was set to 3 mm. Rolled on the upper belt drum to form a bank, spread the syrup in the width direction, shape it into a plate shape, heat the belt with warm water, and proceed with the polymerization of the syrup sandwiched between the belts to make the polymer content 90%. . The plate shaped sheet had a plate thickness of 3 ± 0.1 mm and excellent thickness uniformity and a width of 300 mm and had a good appearance.

Further, the flow rate was continuously increased at a constant belt interval and a constant belt speed, and the syrup was similarly polymerized to a polymer content of 90%. This plate-shaped sheet has a plate thickness of 3 ± 0.1 mm and excellent thickness uniformity, and a width of 400
The appearance was good in mm.

[0017]

INDUSTRIAL APPLICABILITY According to the present invention, a sheet having a desired width can be formed from a high-viscosity syrup containing a polymer without using a sealing material, and a sheet can be produced very easily and economically with great advantage. The present invention provides a method capable of producing the same and has an excellent industrial effect.

[Brief description of drawings]

FIG. 1 is a schematic view of an apparatus useful for carrying out the method of the present invention.

[Explanation of symbols]

 1 ... Gear pump 2 ... Feed pipe 3, 3 '... Endless belt 4, 4', 5, 5 ', 6, 6', 10, 11 ... Roll 8 ... Plate product 9 ... Bank 12 ... Heater 13 ... Pump 14 ... Hot water circulation line

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[Procedure amendment]

[Submission date] March 5, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

That is, according to the method of the present invention, a highly viscous syrup (500 to 50000 poise) containing a polymer is fed in a rod shape by a pipe without using a die and is forcibly rolled by a roll to form a bank. By forming it, it is widened in the width direction, the width is controlled by the flow rate, and shaped into a plate. Syrup used in the method of the present invention comprises a monomer mixture composed mainly of methyl methacrylate alone or methyl methacrylate as a monomer, including a polymer of the monomer as the polymer. In the case of the monomer mixture, methyl methacrylate is preferably 80% by weight or more. Examples of the monomer used together with methyl methacrylate include ethyl methacrylate, propyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, methacrylic acid esters such as benzyl methacrylate, methyl acrylate, and acrylic acid. Examples thereof include acrylic acid esters such as ethyl acidate, butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate and benzyl acrylate, styrene, α-methylstyrene and the like.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

Further, various additives such as an oxidation stabilizer, a plasticizer, a dye, a pigment and a release agent may be added as required. The amount of the polymerization initiator used is appropriately determined depending on the polymerization temperature and the intended polymer conversion rate, but is usually 0.01 to 2% by weight with respect to the monomer mixture. The syrup was mixed adding a polymerization initiator and the like supplied from the pipe, and forcibly rolled with rolls, spread in the width direction by forming a bank, in order to shape the plate, the viscosity of the syrup supply is , Depending on the degree of polymerization, at least 500 pois
It is preferably e. From the viewpoint of productivity, the polymer content of the syrup to be supplied is usually preferably 40% by weight or more.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Motohiro Morikawa 20-1 Miyuki-cho, Otake-shi, Hiroshima Mitsubishi Rayon Co., Ltd. Central Research Laboratory (72) Inventor Hirotoshi Mizoda 20-1 Miyuki-cho, Otake-shi, Hiroshima Mitsubishi Rayon Co., Ltd. Central Research Laboratory (72) Inventor Toshihiko Nishida 20-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Central Research Laboratory

Claims (1)

[Claims] 1. A method for producing a sheet in which a syrup containing a polymer is fed and shaped into a plate with a roll, a high-viscosity syrup containing a polymer is fed into a rod and forcedly rolled with a roll. A method for producing a sheet, which comprises forming a bank to expand the sheet in the width direction, controlling the width by a flow rate, and shaping the sheet into a plate shape.