JPH04353407A - Mold for plastics - Google Patents

Abstract

PURPOSE:To obtain a thin film which has excellent uniformity, wettability, adhesion strength, mold release property, durability, nonadhesiveness on plastics, productivity, etc. CONSTITUTION:A mold for forming plastics is provided, wherein a mold-release thin film containing fluorine, which has, as principal component, a mixture of monomers, oligomers and polymer compounds having radical polymerization fluorine compounds and (meta)acryloyl groups, as end groups, and which is formed by radiation polymerization, is formed over the surface of a cavity of the mold.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic mold used for molding polymeric materials for electrical/electronic parts, optical parts, etc.

0002

BACKGROUND OF THE INVENTION In recent years, plastic molding technology has made remarkable progress in reducing weight, increasing precision, and improving productivity, and there is particularly great demand for plastic molding technology in the field of optoelectronics.

[0003] As one of these efforts, the development of mold release agents during molding processing is progressing. Methods for using the mold release agent include adding it internally into the polymer material to be molded, or coating the stamper or mold body with the mold release agent. As a mold release agent, silicone oil, mineral oil, derivatives such as paraffin wax fatty acid ester, glycol
talc, mica, etc. are used. In addition, in recent years, mixtures of perfluoroalkyl group-containing phosphoric esters or their salts and silicone oil (Japanese Patent Publication No. 53-232
70, Special Publication No. 53-23271), Special Publication No. 57-4
8035, etc., a mixture of a perfluoroalkyl group-containing polyether compound and a silicone oil (Japanese Patent Publication No. 59-3
No. 2513), silicone oil type (JP-A No. 63
-153510, JP-A No. 62-59672, JP-A No. 62-59672), fluorine compounds (JP-A No. 61-Sho.
No. 35910, JP-A-62-21512, JP-A-62
-25914, JP-A-1-157808, JP-A-6
3-104804, JP 1-291908, JP 2-125708, JP 2-141210)
has become the mainstream. Furthermore, the above mold release agent is mixed with other polymeric substances, diluted with a solvent system, and formed on the mold surface by dipping, airless spraying, electrostatic spraying, aerosol spraying, etc. Alternatively, a method has been proposed in which a coating is formed on the mold surface by a dry method such as a sputtering method (Japanese Patent Application Laid-Open No. 166914/1999).

0004

[Problems to be Solved by the Invention] However, conventional plastic molds have the following problems. (1) The adhesion of the mold release agent to the mold body is poor, and although the mold release effect is initially effective, it gradually decreases, so it must be applied each time after several times.

(2) When coating a mold body with a mold release agent, cissing, sagging, etc. are likely to occur. However, in the future, optoelectronics and the like will require complex shapes and highly precise molding. In addition, regarding the optical properties and precision molding of plastic lenses, optical memory substrates, etc., we also consider adhesion to molds, repeatability of mold release, durability against molding temperatures, properties of molded polymer materials (optical properties), etc. etc.), etc., there is currently no sufficient release coating agent available.

The present invention has been made in view of the above circumstances, and consists mainly of a mixture of a radically polymerizable fluorine-based compound and a monomer, oligomer, or polymer compound having a terminal (meth)acroyl group, and By providing a fluorine-containing mold release thin film formed by radiation polymerization on the mold cavity surface, coating surface uniformity, wettability, adhesion, mold releasability, durability, and non-sticking property with synthetic resins are achieved. It is an object of the present invention to provide a plastic mold that has excellent productivity and can avoid adverse effects on molded products due to transfer.

[0007]

[Means for Solving the Problems] The present invention provides a radically polymerizable fluorine-based compound and a terminal group (
Plastic molding, characterized in that the main component is a mixture of monomers, oligomers and polymer compounds having meta)acroyl groups, and is provided with a fluorine-containing mold release thin film formed by radiation polymerization. It is a type.

In the present invention, the radically polymerizable fluorine compounds include the following [Chemical formula 1], [Chemical formula 2], [Chemical formula 3],
[Chem. 4], [C. 5], [C. 6], [C. 7], [C. 8],
Examples include [Chemical Formula 9] and [Chemical Formula 10].

[0009]

[Chemical formula 1]

0010

[Case 2]

[0011]

[Chemical formula 3]

0012

[C4]

[0013]

[C5]

[0014]

[C6]

[0015]

[C7]

[0016]

[Chemical formula 8]

[0017]

[Chemical formula 9]

[0018]

[Chemical formula 10]

The above-mentioned radically polymerizable fluorine-based compound is produced using a known synthesis method using a macromonomer, that is, an oligomer having a polymerizable functional group at one end of the molecular chain, as at least one raw material component. Examples include macromonomers. The alkyl group of the fluoroalkyl group is 4
-20 is preferable, and the following [chemical formula 11] is mentioned, for example.

[0020]

[Chemical formula 11]

Furthermore, regarding the above fluorine-based macromonomer, the above fluoromonomer is radically polymerized in the coexistence of thioglycolic acid to obtain a molecular weight of 1,000 to 10,000.
A one-terminated carboxylic acid prepolymer is obtained, and a fluorine-based macromonomer and a graft polymer having a (meth)acrylic acid ester group are obtained by reaction with glycidyl methacrylate.

In the present invention, the fluorine-containing macromonomer and its derivatives obtained by the macromonomer method are used as the following (meth)acroyl group radiation polymerizable monomers and oligomers.
and had good compatibility with the polymer. Radiation polymerizable (meth)acroyl group monomers, oligomers, and polymers include monofunctional and polyfunctional types, such as those described below. (1) Epoxy acrylate system; for example, the following [Chemical formula 12
].

[0023]

[Chemical 12] (2) Urethane acrylate system; for example, the following [Chemical 13
], [Chemical formula 14].

[0024]

[Chemical formula 13]

[0025]

[Chemical 14] (3) Polyester acrylate; For example, the following [Chemical 1
5].

[0026]

[Chemical formula 15]

(4) Polyether acrylate, (5
) vinyl/acrylate, (6) polyene/thipho
(7) Polybutadiene, etc., and fluorinated epoxy acrylate (Proceeding of Ra
diation Curing ASIA, 1LI,
p69, 1869), monofunctional monomers such as bidroxyethyl acrylate and allyl acrylate, and dipolyfunctional monomers such as neopentyl glycol diacrylate and tetraethylene glycol diacrylate. -, trifunctional monomers of pentaerythritol triacrylate and trimethylolpropane triacrylate, and dipentaerythritol hexaacrylate
Various types of monomers and oligomers can be mentioned, such as a hexafunctional monomer.

In the present invention, methods for forming a fluorine-containing mold release thin film on the surface of a stamper or mold for plastic molding include a spray method, an electrostatic coating method, a deep coating method, a brushing method, and a spinner method. etc. Figure 1
1 shows a schematic diagram of a spin coating machine, and 1 shows a rotating table.
3 is a workpiece adhered to the upper surface of the rotary table 2 with double-sided tape, 4 is a cover, and 5 is a dropping funnel.

The fluorine-containing release thin film is formed into a crosslinking reaction type film by radiation polymerization, such as electron beam polymerization or ultraviolet polymerization (UV method). In addition, when using the ultraviolet polymerization method, it is necessary to use an ultraviolet initiator in the mixture of the radically polymerizable fluorine-based compound and the monomer, oligomer, and polymer compound having a terminal (meth)acroyl group. In addition, in order to further improve leveling performance,
For example, the following additive [Chemical formula 16] may be added.

[0030]

embedded image In place of the above additives, general additives such as a fluorine leveling agent may be added.

[0031]

[Operation] According to the present invention, the uniformity and wettability of the coating surface,
A plastic mold can be obtained that has excellent adhesion, releasability, durability, non-stick properties with synthetic resin, productivity, etc., and can avoid adverse effects on molded products due to transfer.

[0032]

[Examples] Examples of the present invention will be described below along with manufacturing methods. (Example 1)

First, on the Cr-plated Fresnel nesting surface of a Fresnel lens for camera screen molding with a pitch of 0.05 mm, a release coating liquid having the following composition was applied using a spinner method at a rotation speed of 1200 ppm. A film with a thickness of approximately 400 angstroms (40 nm) was formed at a shaking speed, and the film was subjected to a crosslinking reaction by scanning two OAK Seisakusho ultraviolet irradiation lamps (concentrated type 160 W/cm2) at a speed of 30 m/min. . Reaction product of isocyanalic acid derivative and polyisocyanate compound (manufactured by Dainichi Ink Co., Ltd., product name: Unitic 1
8-845M)
...46 parts by weight trimethylolpropane triacrylate
...20 parts by weight Neopentyl glycol diacrylate ...10
Parts by weight Photopolymerization initiator (Ingarcure 651/2
-Chlorthioxanthone/benzoisobutyl ether=
6/3/2)
...6 parts by weight perfluoroalkyl acrylate (Chemical formula 17 below)
...13 parts by weight Phosphoric acid derivative (trade name: Kayama-PM2, manufactured by Nippon Kayaku Co., Ltd.)...4 parts by weight

0
034 Leveling agent (below [Chemical formula 18])

0.5 parts by weight of the above coating composition was mixed with fluorocarbon solvent S.
A mixed solvent of -12/ethyl acetate/IPA (mixing ratio = 4:4:2) was applied with a fixed content of 3% by the spin coating method described above, and a crosslinking reaction was carried out using a high-pressure mercury lamp.

[0035]

[Chemical formula 17]

[0036]

[Chemical formula 18]

The plastic mold obtained as described above has a structure in which a fluorine-containing mold release thin film obtained by applying the above composition is formed on the surface of the mold. Such a mold has the following effects. (1) A uniform film is formed, and the transferability of the prenel lens shape by the acetic acid resin is good. (2) Good adhesion to the mold. (3) Due to the above (1) and (2), the number of shot molding times is very good. (4) Good mold releasability. (Example 2)

First, 200 parts by weight of the following [Chemical formula 19] and 200 parts by weight of benzotrifluoride were charged into a dropping funnel, and 3-mercaptopropionic acid 7 was added to the other funnel.
．． A mixed solution of 1 part by weight, 4 parts by weight of azobisisobutyronitrile, and 100 parts by weight of benzotrifluoride was added. Next, a reaction was carried out at 70°C for about 4 hours in N2 to achieve a polymerization addition rate of fluoroacrylate of about 96%.The reaction solution was then heated to reflux for 2 hours, and then cooled to bring the solution temperature to 90%.
It was kept at ℃. Furthermore, 0.1 parts by weight of hydroquinone monomethyl ether and 13 parts by weight of glycidyl methacrylate were added thereto.
95 parts by weight, tetrabutylammonium bromide 2.
5g was added. Thereafter, the reaction was carried out at 90° C. for 6 hours by switching from N2 gas to air blowing, and the reaction solution was poured into 10 times the amount of methanol or more to precipitate, and a fluorine-based macromonomer was obtained by drying under reduced pressure.

[0039]

[Chemical formula 19] The above fluorine-based macromonomer
...60 parts by weight dipentaerythritol hexaacrylate
...10 parts by weight oligoester acrylate (product name: Aronix-7200
X, manufactured by Toagosei Chemical Industry Co., Ltd.)

...10 parts by weight neopentyl glycol diacrylate
...10 parts by weight Product name: Kayama-PM2 manufactured by Nippon Kagaku Co., Ltd.
... 5 parts by weight photopolymerization initiator (same as Example 1)

... 5 parts by weight

The above coating composition was mixed with ethyl acetate/toluene/IPA (mixing ratio = 6:3:2).
), a release film was formed on the surface of a 1.6 μm pitch, 5-inch optical disk stamper by spin coating at a rotation speed of 1500 rpm. After this, Example 1
Similarly, it was cured using a high-pressure mercury lamp. Further, even when the photopolymerization initiator was omitted and the crosslinking reaction was carried out by the EB curing method, a good film could be obtained.

[0041] When the above stamper was used to mold acrylic resin or polycarbonate resin, Example 1 was obtained.
Similarly, it was excellent in moldability, durability, adhesion, mold releasability, and optical properties.

[0042]

Effects of the Invention As detailed above, according to the present invention, the main component is a mixture of a radically polymerizable fluorine compound and a monomer, oligomer, or polymer compound having a terminal (meth)acrylic group, and By providing a fluorine-containing mold release thin film formed by radiation polymerization on the stamper or mold surface, the coated surface can be improved in uniformity, wettability, adhesion, mold releasability, durability, and non-sticking with synthetic resin. It is possible to provide a plastic mold that has excellent performance, productivity, etc., and can avoid adverse effects on molded products due to transfer.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a spin coating machine used when forming a fluorine-containing mold release thin film on a mold body according to the present invention.

[Explanation of symbols]

1... Rotating shaft, 2... Rotating table, 3... Work, 4... Cover.

Claims (2)

[Claims] Claim 1: The surface of the mold cavity is coated with a radically polymerizable fluorine-based compound and a mixture of monomers, oligomers, and polymer compounds having terminal (meth)acroyl groups as the main components, and is produced by radiation polymerization. A plastic mold comprising a fluorine-containing mold release thin film. 2. The plastic mold according to claim 1, wherein the radically polymerizable fluorine compound is a radically polymerizable fluorine compound obtained by a macromonomer method.