JPS61281101A - Method for cast polymerization - Google Patents

Abstract

PURPOSE:To obtain a polymer of high purity without contamination of impurities, by applying an adhesive to the peripheral part of a pair of molds or applying a double-sided adhesive thereto, integrating the molds with a film and injecting a monomer or oligomer in the cavity thereof. CONSTITUTION:Cast polymerization is carried out using a pair of molds. In the process, an adhesive is applied to the respective peripheral parts thereof with preferably a roll coater, or a double-sided adhesive, e.g. double-sided adhesive tape such as adhesive transfer tape, is applied to thereto. The above- mentioned molds are then integrated with a film and a monomer of oligomer is injected into the cavity formed by the molds and the film to carry out polymerization. USE:Plastic lenses of high quality can be efficiently produced at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for casting polymerization of plastic lenses and the like. In more detail, it relates to a technology for producing highly pure plastic lenses without contaminants from Monomaya oligomers.

[Conventional technology]

Cast polymerization using conventional films is well known. For example, U.S. Patent No. 3,211,811, Japanese Patent Publication No. 3
9-29199 describes the use of adhesive tape to form a cavity between molds.

Also, JP-A-56-135029, JP-A-56-1
35030, JP-A-56-13503'1, etc. also describe casting polymerization using an adhesive tape.

However, this conventional technique has the disadvantage that the adhesive of the adhesive tape dissolves into the monomer or oligomer, making it impossible to obtain a cast product of high purity. In addition, the composition in the pressure-sensitive adhesive of the adhesive tape inhibits the polymerization and curing reaction of the adhesive tape, resulting in the drawback that curing does not proceed or the curing time becomes extremely long. Improvements to these drawbacks have been strongly desired by the industry.

(Problems to be Solved by the Invention) The present invention improves the above-mentioned drawbacks of the prior art, and maintains adhesives and pressure-sensitive adhesives substantially non-contact with polymerized monomers and oligomers, thereby ensuring good adhesion during polymerization and curing. Excellent and heat resistant,
To provide a technology that has excellent oxygen barrier properties, prevents the adhesive from dissolving into monomers, provides high quality lens products, and enables efficient manufacturing.

[Means for solving problems]

In order to achieve the above object, the present invention has the following configuration.

(1) When performing cast polymerization using a pair of molds, first apply adhesive to the periphery of each of the pair of molds, or paste double-sided adhesive, and then A cast polymerization method characterized by integrating a pair of molds with a film, and then injecting and polymerizing a seven-piece mold or an oligomer into a cavity formed by a pair of molds and a film. It is necessary to apply adhesive to the periphery of each mold or apply double-sided adhesive. This is to attach the film in the next step.

Next, the pair of molds are wrapped in film and integrated. This is to create a molding space (cavity) and perform polymerization within this cavity. The mold is usually glass or plastic,
Use metal. In addition, a film made of polyethylene terephthalate, polypropylene, or the like is used. During polymerization, even if the polymerization and shrinkage of the oligomers occurs, the film only wrinkles following the polymerization, so no voids or distortions occur, and the product can be polymerized stably. The thickness of the film may be of any value, but is preferably about 30 to 100 microns. Further, these base films may be subjected to corona discharge treatment, plasma treatment, etc.

Next, the monomer is placed in the cavity obtained as described above.
Or inject oligomer and polymerize. At this time, if the injection port is opened with a slight slit without wrapping the entire film, the monomer or oligomer can be efficiently injected from the injection port using high pressure. As another method, the films may be rolled to such an extent that they overlap, and then the overlapped portion is opened and the nanatsuma or oligomer is injected through this gap. Alternatively, a hole may be made in the tape for air handling, and a needle for injecting the monomer or oligomer may be inserted through the tape.

This injection port is then sealed with adhesive tape and subjected to polymerization. Polymerization may also be carried out by heating.

In the present invention, adhesives include urea resin, vinyl acetate resin, melamine resin, phenol resin, natural or synthetic rubber type, silicone type, urethane type, vinyl type,
Any material may be used, such as resorcinol, furfural, petroleum resin, polystyrene, acrylic resin, polymethacrylic resin, celluloid, polycarbonate, epoxy, and α-cyanoacrylate. In the case of a solvent-based solvent, any known solvent may be used. A hot melt type can also be used.

In the case of double-sided adhesive, any of the adhesives mentioned above may be used. Preferably pressure-sensitive adhesive (double-sided adhesive tape)
I'll go. A more preferred method uses an adhesive transfer tape as the double-sided adhesive tape.

An example of this adhesive transfer tape is Tape N, 920 manufactured by Sumitomo 3M.

In the above, preferable adhesives or double-sided adhesives include (1) natural rubber or synthetic rubber; (2) terpene resin as a tackifying resin (so-called tackifier) or aliphatic petroleum synthesized from 05 fraction of petroleum. The adhesive is made of resin or one or more compounds selected from the group consisting of alicyclic petroleum resins synthesized from the C9 fraction of petroleum. This is because this combination has excellent adhesive strength and causes less contamination even if it comes into contact with polymerized monomers and oligomers to some extent.

Here, the terpene resin refers to a homopolymer or copolymer such as α-pinene or β-pinene. Aliphatic petroleum resins synthesized from the C5 fraction of petroleum are copolymerized with a component generally called the C5 fraction, whose main components are isoprene, 1,3-pentadiene, etc. obtained by thermal decomposition of petroleum naphtha. It is a resin that can be used.

What is alicyclic petroleum resin synthesized from the C9 fraction of petroleum?
It is a resin obtained by hydrogenating a resin obtained by polymerizing the residual sludge extracted from BTX from the C6 slough obtained by thermal decomposition of petroleum naphtha.

The natural rubber or synthetic rubber may be of any kind, but particularly preferably a rubber-like elastic body containing polyisoprene or styrene-butadiene rubber as a main component.

The sheet serving as the base material of the double-sided adhesive may be appropriately selected from paper, cloth, and film, but from the viewpoint of chemical resistance, strength, cost, etc., biaxially oriented stretched polypropylene film,
Alternatively, a polyethylene terephthalate film is preferred, and the thickness of this film may be of any value, but is preferably about 30 to 100 μm. These base films may also be subjected to corona discharge treatment, plasma treatment, or primer treatment to improve their adhesion to the adhesive.

In addition, softeners, cross-linking agents, inorganic fillers, anti-aging agents, etc. are appropriately added to the adhesive to the extent that they do not elute into the lens rim and cause turbidity or inhibit polymerization and curing reactions. You can let it happen.

For example, when a film is used as the base material, a method for producing a pressure-sensitive adhesive sheet constituting a double-sided adhesive is to dissolve natural rubber or synthetic rubber and a tackifier in an organic solvent to create a pressure-sensitive adhesive solution. It can be obtained by coating a film and then drying it.

In the present invention, when applying an adhesive or applying a double-sided adhesive, it is preferable to perform the process while holding a pair of molds in their respective holders. This is to prevent dirt and the like from entering.The holder may be of any type, but it is preferable that it has a suction mechanism that uses reduced pressure.When using the holder,
Before or after applying the adhesive or pasting the double-sided adhesive, put a spacer between a pair of molds to keep the cavity space constant in advance, memorize this distance on a gauge, etc., then take out the spacer, After that, it is preferable to return the space in the cavity to a point where the spacer is completely located, and then wind the film.

The adhesive may be applied by any means, but
For efficiency, it is preferable to use a roll coater.

The plastic lens that can be produced by the cast polymerization method of the present invention contains a liquid curable compound containing a benzene ring, a naphthalene ring, a carbonyl ring, a
bond, ester bond, urethane bond, halogen element to 1
One species or those having two or more species are preferably used.

It is particularly effective for plastic lenses having nuclear halogen-substituted aromatic rings. Such plastic lenses can be manufactured by using one or more types of vinyl monomers having the above-mentioned functional groups.

Examples of vinyl monomers having the above functional groups include styrene, styrene substituted with a nuclear halogen, phenyl (meth)acrylate, phenyl (meth)acrylate substituted with a nuclear halogen, benzyl (meth)acrylate, and benzyl (meth)acrylate substituted with a nuclear halogen. 1-, vinylnaphthalene, naphthyl (meth)acrylate, Te1-(di)(meth)acrylate of bromogosphenol A derivative, divinylbenzene, diethylene glycol bisallyl carbonate, tetrabromobisphenol A Methyl methacrylate, (di)ethylene glycol di(meth)acrylate-1~, tetrabromobisphenol A Reaction product of M conductor monohydroxy acrylate and polyfunctional isocyanate such as xylylene diisocyanate 1~, hexamethylene diisocyanate, nuclear halogen These include reaction products of substituted phenol derivative monohydroxyacrylate-1 to polyfunctional isocyanate, reaction products of monohydroxyacrylate of nuclear halogen-substituted biphenyl derivative and polyfunctional isocyanate, and mixtures thereof.

〔Example〕

EXAMPLES In order to roughly and specifically explain the present invention, examples will be shown below. Of course, the present invention is not limited to these examples.

Example 1 100 parts by weight of natural rubber,
Terpene resin (made by Souryo Yushi, product name “YS Resin”)
PX #1000) 80 parts by weight, 30 parts by weight of aliphatic petroleum resin made from C5 fraction (manufactured by Nippon Zeon, trade name "Finton" 8170), and 840 parts by weight of toluene, approximately 25μ Double-sided adhesive tape coated with a thickness of about 5 mm was pasted on the outer periphery of a pair of molds (one piece having a thickness of about 5 mm).Then, each of the pair of molds was held in a vacuum suction type holder. , First, insert a spacer to adjust the cavity distance to 10mm, then remove the spacer, adjust it to 1Qmm again, and in this state make the cavity width 4.
A biaxially oriented polyethylene terephthalate film having a thickness of 38 μm and a thickness of 38 μm was wound around the tube.

The film that jumped out of the mold was cut and removed.

Into the mold thus assembled were 50 parts by weight of 2゜2'-bis(4-methacryloxyethoxy-3゜5-dibromophenyl)propane, 50 parts by weight of styrene, and 0.1 type of diisopropyl peroxydicarbonate. A liquid curable compound consisting of a set part is injected and heated from 40°C to 110°C.
The temperature was gradually raised over 30 hours until the polymerization reaction was completed. After slowly cooling to room temperature, it was taken out from the polymerization tank and the adhesive tape was removed. The area in close contact with the adhesive tape was sticky, but this was resolved by immersing it in toluene at 40°C for 5 minutes. In addition, mold release was easily performed using the heat shock method.

The obtained lens was colorless and transparent, with no clouding due to the elution of the adhesive, and no chipping due to leakage of the liquid curable compound. In addition, the lens was optically good with no distortion.

On the other hand, when similar cast polymerization molding was performed using adhesive tape coated with a commercially available rubber adhesive, the lens became cloudy due to the elution of the adhesive and the lens was deformed due to misalignment of the mold, resulting in unsatisfactory results. I couldn't get the lens.

Example 2 Synthetic natural rubber (manufactured by Kuraray Co., Ltd., trade name “IR-10”)
100 parts by weight terpene resin (
Soryo Yushi product name “YS Resin” Px #1000)
60 parts by weight Terpene resin (Souryo Yushi product name: "YS Resin"Px#700)
An adhesive composition consisting of 760 parts by weight of cyclohexane was applied to the periphery of a pair of glass molds using a roll coater, and then a polyethylene terephthalate film was wrapped around the molds in the same manner as in Example 1. A mold for cast polymerization was assembled.

A liquid curable compound consisting of 100 parts by weight of diethylene glycol bisallyl carbonate and 3 parts by weight of isopropylpaoxycarbonate was injected into the mold.
The temperature was gradually raised from .degree. C. to 90.degree. C. over 20 hours to complete polymerization. Release from the mold was easy as in Example 1, and the resulting lens had a colorless and transparent appearance with no chips or turbidity.
There was no optical distortion.

Example 3 A double-sided adhesive tape was obtained by applying the following composition to a thickness of 40 μm on a polyester film having a width of 5 mm and a thickness of 50 μm.

Aliphatic petroleum resin synthesized from natural rubber 100 heavy Osuma fraction (manufactured by Mitsui Petrochemical Co., Ltd., product name "Hiretsu IT T-100")
Aliphatic petroleum resin synthesized from 80 parts by weight C5 fraction (manufactured by Nippon Zeon Co., Ltd., product name "Fin 1-N" B)
-170) 30 parts by weight
Wrap the double-sided adhesive tape of Silun 840 840 double-sided mold mouth around the side surface of the mold in the same manner as in Example 1, wrap the polyethylene terephthalate 1 to film over it in the same manner as in Example 1, and mold the plastic lens. Assemble the mold for it.

In this mold, hexamethylene diisocyanate,
7 parts by weight, 2-(4-acryloxyethoxy-3,5-
dibromophenyl)-2-(4-hydroxyethoxy-
3,5-dibromophenyl)propane 63 parts by weight, divinylbenpine 30 parts by weight, dibutyltin dilaurate 0.
01 parts by weight, tert-butyl peroxide O
Inject 81 parts by weight of a liquid curable compound and heat at 60°C.
The temperature was gradually raised from 120'C to 120'C over 30 hours to complete the polymerization reaction.

The double-sided adhesive Cheap had very good heat resistance and did not melt or deform even at 120°C.

The adhesive tape was removed and the stickiness was removed by washing with 1 to 1 to 1 luene.

The obtained lens was colorless, transparent, and beautiful, with no chipping due to leakage of the liquid curable compound, and no turbidity due to the release of the adhesive. In addition, a good lens without optical distortion was obtained.

(Effects of the Invention) The method for manufacturing plastic lenses using the adhesive tape of the present invention has the following superior features compared to conventional methods.

(1) Since there is substantially no adhesive on the walls constituting the cavity, there is no elution of the adhesive into the lens component, and a pure polymerized amount of the component can be obtained. Furthermore, since the tape base material has excellent heat resistance, a wide variety of plastic lenses can be molded under various polymerization conditions.

(2) It is cheaper than gaskets, leading to lower lens manufacturing costs.

(3) By wrapping the adhesive or double-sided adhesive around the mold using a specific holder, the mold assembly operation becomes simple, time is shortened, and efficient manufacturing becomes possible.

(4) Since the film can withstand high temperatures and is capable of high-temperature polymerization, the polymerization temperature range can be widened and stabilized, making it easier to obtain high-quality lenses and shortening molding time.

(5) It is possible to eliminate the influence of oxygen in the polymerization range, making it easier to obtain colorless lenses.

Claims (5)

[Claims] (1) When performing cast polymerization using a pair of molds,
First, adhesive is applied to the periphery of each of the pair of molds, or double-sided adhesive is pasted, and then the pair of molds are integrated with a film, and then inside the cavity formed by the pair of molds and the film. A cast polymerization method characterized by polymerizing by injecting a monomer or oligomer into. (2) In the method described in claim (1),
A cast polymerization method characterized in that when applying an adhesive or pasting a double-sided adhesive, the process is carried out with a pair of molds held in respective holders. (3) In the method described in claim (1),
A cast polymerization method characterized in that adhesive is applied using a roll coater. (4) In the method described in claim (1),
A cast polymerization method characterized in that the double-sided adhesive is double-sided adhesive tape. (5) In the method described in claim (4),
A cast polymerization method characterized in that the double-sided adhesive tape is an adhesive transfer tape.