JP2581116B2 - Manufacturing method of resin mold with fine irregularities - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a plastics flat lens, a vinyl record,
The present invention relates to a method for manufacturing a simple resin mold (= stamper) for molding a plastic molded product having fine functional irregularities on the surface of a compact disk, an optical disk, or the like.

[Conventional technology and its problems]

Conventionally, plastic products having fine functional irregularities on a plane are usually machined with desired irregularities on a metal surface,
It is formed by using a metal mold formed by a method such as chemical processing and mounting it in a normal mold. For example,
The compact disk is manufactured by uniformly applying a photoresist to a desired thickness on a smooth glass substrate, baking a desired pattern by a laser beam, developing the developed pattern, and then applying a hard nickel plating to the surface.

However, manufacturing a metal mold having precise irregularities generally requires special equipment, and has problems such as being expensive and having a long number of metal molds yesterday, and a method for manufacturing such a mold more easily. The development of was desired.

[Means for solving the problem]

The present inventor has conducted intensive studies on the solution of this problem, and as a result, has selected a thermosetting resin composition having heat resistance and capable of faithfully tracing fine functional irregularities, The inventors have found a method for solving the weak points of the thermosetting resin composition by combining it with a metal plate, and have completed the present invention.

That is, the present invention provides a product master in which a functional uneven pattern of 0.05 μm to 1 mm is formed on a flat surface having releasability or a flat surface of a removable substance, and has a minimum viscosity of 1.0 × 10 at a temperature of 100 ° C. or less. ^{2 to} 3.0 × 10 ³ centipoise, a non-solvent addition polymerization type thermosetting resin composition with a glass transition temperature of 100 ° C. or more after curing is placed at a thickness of 1.0 mm or less from the top of the unevenness, and the resin flows by heating. Pre-cured until no more, a metal plate having a smooth flat surface was joined to the pre-cured resin surface, and the addition polymerization type thermosetting resin composition was cured and integrated with the metal plate. A method of manufacturing a resin mold having fine irregularities characterized by being removed from a plate and a resin, and in a preferred embodiment, the product master has a position reference mark portion of an irregular pattern, Metal plate is pre-formed to desired shape A resin mold having a thin layer for adhesion of the addition-polymerization-type thermosetting resin composition on the bonding side of the metal plate with the resin surface, and a resin mold having fine irregularities To form a metal layer having a thickness of 40 μm or less on the surface of the substrate by electroless plating.

 Hereinafter, the configuration of the present invention will be described.

First, the resin mold of the present invention usually includes a stamper or the like that is mounted in a mold and used to give a desired surface shape to a resin molded product. A plastic molded product suitably produced by such a method, and therefore, as a resin mold thereof, is usually a flat lens having irregularities of less than 1 mm, especially irregularities of about 100 to 500 μm smaller than 0.5 mm (such as a Fresnel lens), There are compact discs and optical discs having irregularities of about 0.1 μm, such as record boards, and these are exemplified.

In the production of the resin mold in which the metal plate of the present invention is composited, a product master having a surface releasable or removable is used, and this is subjected to dust control, which can be appropriately controlled such as heating and decompression. Set in a mold for the mold, place the solvent-free liquid thermosetting resin composition in this, pre-cure until it does not flow, then process it into a predetermined shape if desired, and form a metal plate with an adhesive layer After bonding and pressing, the resin is cured, and the resin and the metal plate are integrated, the product master is removed, post-cured (completely cured) as necessary, and further subjected to external processing if desired. It is manufactured by this.

Here, the materials used in the method for producing the resin mold of the present invention are as follows.

(A), product master: a target molded product itself having a concave and convex pattern formed on a flat surface, a model or a target molded product manufactured from a release material that can be accurately molded from the target molded product or a material that can be decomposed and removed. Is a mold with a precisely formed surface shape, and as a material, it can withstand a temperature of about 100 ° C., and usually does not contain fillers and the like thermoplastics such as polyolefin, silicone resin, acrylic resin, epoxy resin, etc. It is made of heat, light or room temperature curable resin, metal, glass or the like. For example, in the case of a compact disk or an optical disk, a thin glass layer (usually having a thickness of 0.1 mm) is applied to a smooth glass surface with a predetermined thickness by a method such as a photoresist spin coating method and dried.
(Approximately 1 μm), baked with a laser beam, and developed. In the case of a flat lens, etc.,
The molded product itself or a polished resin or the like is machined into a desired surface pattern, or a metal is mechanically or chemically processed to produce a mold having a desired surface pattern, or the mold release property is improved. An example is a material obtained by transferring a concavo-convex pattern using a resin having the resin.

(B), metal plate: The thermosetting resin composition for forming the surface layer can transfer a fine uneven pattern faithfully, but lacks dimensional accuracy and strength over long distances, and is used to compensate for this. Things,
Usually, a metal plate having a flat surface with a thickness of 0.1 mm or more is used. Various metals can be used as the metal, but those having good dimensional stability, high strength, and excellent adhesion to the thermosetting resin to be used are preferable, for example, a nickel plate, a steel plate, a stainless steel plate, An aluminum alloy plate or the like is used, and it is particularly preferable to use it after processing into a desired shape.

In addition, it is necessary to precisely transfer fine irregularities and form a thin adhesive layer on the side of the metal plate that adheres to the resin from the surface that better achieves the flatness of the irregularities and the positioning accuracy over long distances. It is a preferred embodiment to form an adhesive composition layer having a stress relaxation property in order to reduce the difference in the coefficient of thermal expansion between the resin for the resin mold and the metal plate.

(C) Solvent-free, unfilled liquid addition-polymerizable thermosetting resin composition: 1.0 × 10 ^{2 to} 3.0 × 10 ³ centipoise, preferably 5.0 × 10 ^{2 to} 1.5 × 10 ³ centipoise at a temperature of 100 ° C. or less. And a glass transition temperature after curing of 100 ° C. or higher, preferably 120 ° C., and a solvent-free, filler-free addition-polymerizable curable resin composition. Specifically, cyanai resins (Japanese Patent Publication Nos. 41-1928, 45-11712, 44-2222, DE-1,190,1
84, UPS-4,578,439, etc.), cyanate-epoxy resin (JP-B-46-11112, etc.), cyanate-ester-maleimide resin, cyanate-ester-maleimide-epoxy resin (JP-B-54-30440, JP-B-52-31279, USP-4,110,364
Etc.) cyanate ester resins; bisphenol F type epoxy resin, bisphenol A type epoxy resin, alicyclic epoxy resin, novolak type epoxy resin, epoxy resin derived from xylylenediamine, epoxy resin derived from diaminodiphenylmethane , Polyfunctional epoxy resins using other polyfunctional epoxy compounds; modified maleimide resins containing polyfunctional maleimide compounds and epoxy compounds and isocyanate compounds as main components; isocyanate compounds and epoxy compounds as main components Isocyanate-oxazolidone resin (JP-A-55-7541)
No. 8, etc.), and modified 1,2-polybutadiene resin, diallyl phthalate resin, silicone resin and the like are exemplified. In particular, a cyanate ester-based resin is exemplified.

Further, since it is necessary that the resin has no solvent and low viscosity, a curable monomer or a prepolymer may be blended with these resins, and further a curing catalyst may be blended for use.

Examples of the curable monomer include polyfunctional (meth) acrylates such as polyfunctional (meth) acrylate, alkyl (meth) acrylate, triacryloxy isocyanurate, triacryloxy cyanurate, and ethoxy (meth) acrylate; diallyl Examples include polyfunctional allyl compounds such as phthalate, divinylbenzene, and trialkenyl isocyanurate; dicyclopentadiene, cyclopentadiene and prepolymers thereof; aromatic vinyl compounds such as styrene and vinyltoluene; and monofunctional epoxy compounds. .

Examples of the catalyst include those known for each resin and resin composition, and include organic peroxides, azo compounds, imidazole and adducts of carboxylic acids or carboxylic anhydrides, tertiary amines, phenols, and the like. Various compounds such as an organic acid metal salt, an adduct of an organic acid metal salt and phenol or bisphenol, an inorganic metal salt, a metal chelate compound, an organic tin compound, and an acid anhydride are exemplified. Particularly, a preferred cyanate ester-based composition of the present invention. In the case of a product, an organic oxide, an organic metal salt, a metal chelate compound, an organic tin compound and the like are preferable.

Using the above (a), (b) and (c) as main elements, the resin mold (stamper) of the present invention is manufactured. This manufacturing example will be described with reference to an example of a method of producing a stamper for compact disk injection molding. (1), a set of casting models: a note with dust management capable of controlling heating, decompression, etc. A model in which a photoresist pattern is formed horizontally on a smooth glass plate is set in a mold for a mold.

(2) Arrangement of addition-polymerization-type thermosetting resin: The solvent-free and unfilled low-viscosity addition-polymerization-type thermosetting resin composition liquid of the present invention separately prepared for the model is usually heated at a temperature of 100 ° C. or lower. It is applied thinly (1 to 100 μm) below, the inside of the system is depressurized, the surface is made as smooth as possible by appropriate ultrasonic vibration or other methods, and is usually pre-cured by heating at a temperature of 100 ° C. or less.

(3) Preparation of a metal plate.

A metal plate having a high-strength smooth surface with excellent dimensional stability of a desired thickness is cut into a desired shape, and the adhesive is thinned as thinly as possible under a dust-controlled environment (1 to 100 μm).
m) is applied, and the surface is made as smooth as possible by other methods such as ultrasonic vibration under reduced pressure as appropriate.

(4) Bonding and curing of the metal plate: The metal plate prepared in (3) above is horizontally held and aligned on the model resin in the casting mold prepared in (2) above. superposed, and a state where the held so as not to cause positional Families, the inside of the mold for casting the vacuum, heating, and while pressing a metal plate at low pressure (about 1 kg / cm ^2), the resin was gelled And further raise the temperature to cure.

(5) Removal of the composite resin mold, etc .: The model and the integrated resin mold are taken out of the casting, and the excess resin adhering around the resin mold is removed, and then the glass plate is peeled off.

At this time, if the adhesive strength between the resin of the photoresist and the resin for the present resin mold is large, the photoresist is adhered to the obtained composite resin mold side, and this is removed with a resist stripping agent.

As described above, an example of the method for producing the resin mold (stamper) of the present invention has been described, but the method of the present invention is not limited to the above-described method.

〔Example〕

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

Example 1 [Plastic lens] 400 m long with a lens pattern formed on one side made of stainless steel
A metal plate having a width of 400 mm, a width of 1 mm, a thickness of 1 mm, and a height of lens unevenness of 1.0 mm was used as a model.

This model was fixed horizontally in a casting mold with the lens pattern surface facing up, and a 20 mm high frame was made around it.

A 15 mm thick plate made of an aluminum alloy was cut to have the same outer shape as the plastic lens.

On the other hand, 2,2-bis (4-cyanatophenyl) propane was preliminarily reacted at 160 ° C. for 3 hours to obtain a liquid prepolymer, and 90 parts by weight of the prepolymer and a tetrafunctional derivative derived from metaxylenediamine were used. 10 parts by weight of an epoxy resin (trade name: Tetrad, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was mixed to prepare a liquid thermosetting resin composition (hereinafter referred to as resin 1) having a temperature of 75 ° C. and 700 centipoise. .

Similarly, 70 parts by weight of the same liquid prepolymer as above,
Substantially amorphous thermoplastic saturated polyester resin (trade name: Polyester LP-035, Nippon Synthetic Chemical Industry Co., Ltd.)
30 parts by weight) and 0.05 parts by weight of zinc octylate,
An adhesive composition (hereinafter referred to as adhesive 1) was prepared by dissolving and mixing in methyl ethyl ketone.

The resin 1 prepared above was heated to 60 ° C., applied to the model surface in a casting mold maintained at 60 ° C., and the pressure inside the system was reduced to 3 mmHg to completely remove air bubbles. 14 as 75 ° C
After holding for a time, the applied resin was gelled. The thickness of the gelled resin layer was about 0.3 mm from the top of the lens irregularities.

On the gelled resin, the adhesive 1 was applied to one side of the aluminum plate prepared above and dried at 110 ° C. for 10 minutes to obtain a metal plate with an adhesive layer having a thickness of 0.15 mm. After superimposing, pressing at 1 kg / cm ² and heating at 100 ° C. for 24 hours, removing the model (= stainless steel plate), heating at 170 ° C. for 3 hours to completely cure the resin,
A peripheral resin and the like were removed to obtain a resin mold.

The resin mold obtained above was set in a mold to form a mold for injection molding, and using this, the acrylic resin was heated to a resin temperature of 220.
Injection molding was performed at 72 ° C. and an injection pressure of 72 kg / cm ² to obtain a good plastic lens molded product made of an acrylic resin.

Example 2 For the molding of the surface irregularities at the submicron level, a model was conveniently prepared by the following method, and a resin mold was manufactured and evaluated.

A stamper for a compact disc is stuck on a smooth glass plate, a photoresist solution is applied to it, and it is kept under reduced pressure to completely remove bubbles and the like. Then, a photoresist film having a layer thickness of 0.1 mm was obtained by using a model, and this model was temporarily adhered to a horizontally rotatable table in a casting mold, with the uneven surface facing upward, and fixed.

On the other hand, 2,2-bis (4-cyanatophenyl) propane was preliminarily reacted at 160 ° C. for 3 hours to obtain a liquid prepolymer, and 80 parts by weight of this prepolymer was mixed with a bisphenol A type epoxy resin (trade name: Epicoat 871). And 20 parts by weight of an epoxy equivalent of 390 to 470, a viscosity of 4 to 9 poise (at, 25 ° C.) manufactured by Yuka Shell Epoxy Co., Ltd.
× 10 ³ centipoise thermosetting resin composition of the liquid (hereinafter referred to as Resin 2) was prepared.

Also, after cutting a 10mm thick aluminum alloy plate into a donut plate with the same diameter as the stamper, one side is precision polished,
The resin 2 was applied to the polished surface and heated to prevent the resin from flowing.

Heat the resin 2 prepared above to 60 ° C, drop it on the model surface in the casting mold held at 60 ° C, and rotate the table while depressurizing the system to 3mmHg to completely remove bubbles. After the coating was performed uniformly, the flowability of the applied resin was eliminated by setting the temperature to 75 ° C. The thickness of the resin layer was about 50 μm.

In the same manner as above, the resin 1 was applied on the polished surface of the aluminum alloy plate prepared above, and dried at 110 ° C. for 10 minutes. Metal plates are stacked on top of each other, and the pressure is 1kg / cm
After 24 hours of heating at 100 ° C. and pressed at ^2, after heated for 3 hours at a temperature 170 ° C. to completely cure the resin, to remove excess resin around, then after removal, stripping the photoresist It was removed with an agent to obtain a resin mold (stamper).

When the stamper and the resin mold (stamper) were examined with a scanning electron microscope, it was found that copying of fine irregularities was good.
In addition, the dimensional accuracy of long-distance irregularities was compared with a photoresist model, and the dimensional tolerance could be explained by the difference proportional to the coefficient of thermal expansion of the aluminum alloy plate. Was confirmed.

When a thin metal plate is used, it is necessary to apply the resin layer as thinly and uniformly as possible in order to eliminate the occurrence of distortion.

[Action and Effect of the Invention]

As is clear from the detailed description of the present invention and the examples, the resin mold according to the method of the present invention is a resin mold (stamper) which is extremely simple compared with the conventional method of cutting and polishing metal, and the method of plating metal. Can be manufactured.

Therefore, because the mold (stamper) is expensive,
What was economical only in the case of mass-produced products can be economically manufactured, and this has an extremely large industrial and cultural significance.

Claims (5)

(57) [Claims] 1. A product master having a functional irregularity pattern of 0.05 μm to 1 mm formed on a flat surface having releasability or a flat surface of a removable substance has a minimum viscosity of 1.0 × 10 ^{2 at} a temperature of 100 ° C. or less. ~ 3.0 × 10 ³ centipoise, glass transition temperature after curing 100 ° C. or higher solvent-free addition polymerization type thermosetting resin composition is placed at a thickness of 1.0 mm or less from the top of the unevenness, and the resin flows by heating. Pre-cured until it runs out,
After joining a metal plate having a smooth flat surface to the pre-cured resin surface, curing the addition polymerization type thermosetting resin composition and integrating with the metal plate, the model is removed from the metal plate and the resin. A method for producing a resin mold having fine irregularities, characterized by the following. 2. The product master according to claim 1, wherein said product master has a position reference mark portion of a functional uneven pattern.
The production method described in the section. 3. The method according to claim 2, wherein said metal plate is previously processed into a desired shape. 4. The metal plate according to claim 1, wherein a thin layer for bonding the addition polymerization type thermosetting resin composition is formed on the side of the metal plate joined to the resin surface. Production method as described. 5. The method according to claim 1, wherein a metal layer having a thickness of 40 μm or less is formed on the surface of the resin mold having the fine irregularities by electroless plating.