JPH08151557A - Light-shading adhesive sheet or tape - Google Patents

Abstract

PURPOSE: To provide a light-shading adhesive sheet or tape overcoming the defects such as uneven coloring, pinholes or film deformation. CONSTITUTION: This light-shading sheet or tape comprises a dyed film and a light-shading adhesive sheet or tape which is made of the same dyed film coated with a transparent adhesive layer on one surface where the dyed film is prepared by dyeing a two-layer film consisting of polyethylene terephthalate film containing a white inorganic compound and a number of fine pores and another polyethylene terephthalate film not containing the white inorganic compound with a disperse dye, and the light in the wavelength region of 300-580nm is substantially screened. The adhesive layer is formed on the white inorganic compound-containing side in the two-layered film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-shielding pressure-sensitive adhesive sheet or tape used as a light-sensitive masking material for light-shielding a light-sensitive material in the printing field such as photolithography.

[0002]

2. Description of the Related Art Generally, a light-shielding pressure-sensitive adhesive sheet or tape comprises a dyeing film and a transparent pressure-sensitive adhesive layer formed on one side of the film, and the dyeing film material is transparent and strong. A polyethylene terephthalate (hereinafter abbreviated as PET) film is preferably used.

The production of a colored PET film is carried out by a masterbatch film-forming coloring method, a coating coloring method, a dyeing coloring method and the like.

The masterbatch film-forming coloring method is a method for forming a colored film by forming a resin blend in which dyes, pigments, colorants and the like are kneaded, and for example, a PET resin contains a specific polystyrene and a specific inert inorganic material. There is known a method of forming a compound containing a compound in a predetermined amount on a white PET film (see Japanese Patent Publication No. 54-29550). The colored PET film produced by this method is white or black, and the colored films having other color tones are not produced because they are not profitable due to low demand.

The coating coloring method is a method of obtaining a colored film by coating a resin composition containing a dye, a pigment, a coloring agent and the like on the film. In this method, coloring is performed by gravure coating, roll coating, screen printing, or the like. The dyeing and coloring method is a method of dyeing a transparent film with a dye to obtain a colored film.

[0006]

However, each of the above methods has the following problems. In the masterbatch film forming method, 1) the transparency is reduced due to the use of pigments, and 2) the cost of the colored film produced in small quantities becomes high.
3) It is difficult to match colors between manufacturing lots, and 4) it is difficult to change colors because the machine is dirty.

In the coating coloring method, 1) pinholes and streaks are partially generated due to dust, foreign matters, foaming, etc. 2) film thickness difference, gravure, uneven coloring due to screen printing, pinholes, etc. are partially present. 3) that the coating film tends to curl, 4) the total thickness of the film becomes thick, and 5) the surface of the coating film tends to be damaged.

In the dyeing and coloring method, 1) the pressurizing high temperature dyeing process causes the film to be soaked at a high temperature so that the film is easily deformed 2)
Pressurized high temperature dyeing is economically inferior in terms of equipment and energy,
3) Solvent dyeing has a drawback that it has many problems in terms of film deformation due to solvent, safety aspects, working environment, and the like.

The light-shielding pressure-sensitive adhesive sheet or tape using the colored PET film obtained by the above-mentioned prior art is colored P
Due to the above problems of the ET film, coloring unevenness,
It has problems such as pinholes and film deformation.

An object of the present invention is to provide a light-shielding pressure-sensitive adhesive sheet or tape that overcomes the above-mentioned difficulties.

[0011]

The present invention has been devised to achieve the above object, and a light-shielding pressure-sensitive adhesive sheet or tape comprising a dyed film and a transparent pressure-sensitive adhesive layer formed on one surface of the film. In, the dyed film is
A two-layer film comprising a polyethylene terephthalate film containing a white inorganic compound and having innumerable fine pores and a polyethylene terephthalate film not containing a white inorganic compound is dyed with a disperse dye,
A light-shielding pressure-sensitive adhesive sheet, which is a film that substantially blocks light rays in the light wavelength region of 300 to 580 nm, wherein the pressure-sensitive adhesive layer is provided on the white inorganic compound-free film side of the two-layer film. Or it is a tape.

First, the dyeing film which is the main component of the light-shielding pressure-sensitive adhesive sheet or tape according to the present invention will be described.

The PET resin as a raw material for the film is mainly composed of a repeating structure of ethylene terephthalate units and has a melting point of 260 ° C. or higher.
The intrinsic viscosity is usually 0.55 to 0.70 as measured by the solvent tetrachloroethane-phenol system.

PET containing no white inorganic compound
The film is formed by forming the PET resin into the PET resin without adding a white inorganic compound or a pore assistant.

The dyed PET film of the present invention is usually
Method of forming a white inorganic compound, a PET resin composition containing a vacancy aid added as necessary and a PET resin containing no white inorganic compound, and dyeing the obtained film with a disperse dye Manufactured by.

The white inorganic compound is inert to the PET resin, and examples thereof include compounds containing elements such as titanium, calcium, silicon and barium. Representative examples of white inorganic compounds include titanium dioxide, silicon dioxide, calcium carbonate, barium sulfate, magnesium oxide, aluminum oxide, calcium sulfate and the like. The content of white inorganic compound is PET
The amount is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 8 parts by weight, based on 100 parts by weight of the resin. The average particle size of the white inorganic compound is preferably 0.1 to 20 μm, more preferably 0.1 to 10 μm.

The PET film containing a white inorganic compound is
It has innumerable fine holes. Examples of the pore assisting agent for forming a myriad of fine pores in the PET film include polystyrene and the like. By using the pore assistant together, a film having innumerable fine pores of preferably 0.1 to several 10 μm, more preferably 0.2 to 2 μm can be obtained.

The PET resin composition also contains other polymers,
An antistatic agent, a lubricant, an antifogging agent, a dye, a pigment and the like may be contained.

In the present invention, a PET resin composition comprising the above components and PE containing neither a white inorganic compound nor a vacancy aid.
The T resin is formed into a laminated two-layer non-stretched film by the T-die method or the inflation method co-extrusion which is usually used for producing a PET film.

Subsequently, the two-layer unstretched film is uniaxially or biaxially stretched. The stretching temperature is set according to the secondary transition temperature of PET. The draw ratio is preferably 2
-6 times, more preferably 3-5 times.

As the stretched PET film, 400 to 7
Those having a spectral light transmittance of 1 to 50% in the 00 nm light wavelength region are preferable.

In the two-layer film of the present invention, the ratio of the thickness of the layer containing the white inorganic compound to the thickness of the layer not containing the white inorganic compound is preferably 1: 1 to 10: 1. Examples of such a two-layer film include a film “Crisper” (thickness 25 μm, G1211) manufactured by Toyobo Co., Ltd.

In the present invention, the above two-layer film is dyed,
A dyed film is obtained.

The dye for forming the dyed film is a disperse dye. There are various dyes such as direct dyes, acid dyes, basic dyes, vat dyes, disperse dyes, PE.
Disperse dyes are suitable for dyeing T films.

Particularly preferred disperse dyes are Samaron Golden Yellow HGL and Samaron Orange HB manufactured by Hoechst.
R, BASF Celliton Fast Yellow 4RL, Cellito
n Orange R, Palanil Brown 3REL, palanil Red FRL
, ICI Dispersol Red DB, Bayer R
Examples include esolin Orange 3GL, Foron Red SE-B manufactured by Sand Co., and the like.

In pressure hot dyeing, the temperature is 120 to 130 ° C.
Because of its high degree, a dye that can withstand high temperatures is selected from azo, anthraquinone, diphenylamine, and other disperse dyes. Since the temperature in normal pressure dyeing is 100 ° C. or lower, dyes that cannot be used in pressurized high temperature dyeing can be used, and the range of use of disperse dyes is greatly expanded. The disperse dye may be used alone or in combination of two or more.

Water is generally used as the medium of the dyeing bath containing the disperse dye, but solvent dyeing using an organic solvent can also be carried out. The concentration of the dye in the dyebath is preferably 3 to
It is 15 g / liter, more preferably 3 to 10 g / liter. If necessary, a leveling agent, an accelerating dye, an ultraviolet absorber, etc. may be added to the dyeing bath. Examples of the leveling agent include Uniperol W manufactured by BASF and Diaserver DP-P Liquid manufactured by Mitsubishi Kasei. CL-511 made by Nichika Kagaku Co., Leve Girl made by Bayer Co., Ltd.
Examples include PEW. Examples of the ultraviolet absorber include LP-200 manufactured by Nichika Chemical Co., Ltd. and Sumipon UL manufactured by Sumitomo Chemical Co., Ltd.

The temperature of the dyeing bath is preferably 80 to 130.
C., more preferably 95 to 99.degree. Regarding the dyeing operation, the PET film is repeatedly passed through the dyeing bath,
The cumulative time is preferably 10 to 120 minutes, more preferably 10 to 30 minutes. Thus, PE
T film is dyed in high density and light wavelength range 300-5
A dyed PET film is obtained which substantially blocks the light of 80 nm. Light wavelength range of dyed PET film 300-580
The spectral light transmittance in nm is preferably 0.5% or less, more preferably 0.1% or less. The photosensitizing wavelength of the contact film for light room used for photoengraving is usually 3
The thickness is from 00 to 450 nm, and the film obtained in the present invention has sufficient light shielding properties. Although the ortho film for dark room has a photosensitive wavelength of up to 580 nm, the fog phenomenon at the time of printing should be prevented if the spectral light transmittance at 300 to 580 nm is 0.5% or less at the exposure amount of a normal printing operation. You can

Next, the pressure-sensitive adhesive layer, which is another constituent layer of the light-shielding pressure-sensitive adhesive sheet or tape according to the present invention, will be described.

Examples of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer include acrylic pressure-sensitive adhesives, rubber pressure-sensitive adhesives, silicone pressure-sensitive adhesives and the like.

As the acrylic pressure-sensitive adhesive, in particular, a homopolymer or copolymer of a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 18 carbon atoms, or the above-mentioned (meth) acrylic acid alkyl ester and other functional groups. A copolymer with a polymerizable monomer is preferably used.

Examples of the (meth) acrylic acid ester include butyl acrylate, isobutyl acrylate, hexyl acrylate, octyl acrylate, and acrylic acid-2-
Ethylhexyl, isooctyl acrylate, decyl acrylate, isodecyl acrylate, lauryl acrylate,
Stearyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, decyl methacrylate, isodecyl methacrylate, lauryl methacrylate, stearyl methacrylate and the like are exemplified. It

Examples of the functional monomer include a monomer having a hydroxyl group, a monomer having a carboxyl group,
Examples thereof include monomers having an amide group, monomers having an amino group, and monomers having a pyrrolidone ring.
Examples of the monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate and hydroxypropyl (meth).
Examples thereof include hydroxyalkyl (meth) acrylates such as acrylates. Examples of the monomer having a carboxyl group include α, β such as acrylic acid and methacrylic acid.
-Unsaturated carboxylic acid: maleic acid monoalkyl ester such as butyl maleate: maleic acid: fumaric acid: crotonic acid. Maleic anhydride also gives the same (co) polymerization components as maleic acid. Examples of the amide group-containing monomer include acrylamide, dimethyl acrylamide, and diethyl acrylamide (alkyl (meth))
Acrylamide, N-butoxymethyl acrylamide,
Examples include N-alkoxymethyl (meth) acrylamides such as N-ethoxymethylacrylamide, diacetone acrylamide, and the like. Examples of the monomer having an amino group include dimethylaminoethyl acrylate. Examples of the monomer having a pyrrolidone ring include N-vinylpyrrolidone.

As copolymerizable monomers other than the above, vinyl acetate, styrene, α-methylstyrene, vinyl chloride, acrylonitrile, ethylene, propylene and the like can be used.

In order to produce a copolymer of (meth) acrylic acid alkyl ester, it is preferable that the (meth) acrylic acid alkyl ester is contained in an amount of 50% by weight or more in all the copolymerized monomer components. If the proportion of the (meth) acrylic acid alkyl ester is less than 50% by weight, the pressure-sensitive adhesive does not exhibit sufficient tackiness. More preferably, the proportion of (meth) acrylic acid alkyl ester is 60% by weight or more.

If necessary, a tackifier such as rosin resin, polyterpene resin, coumarone-indene resin, petroleum resin, or terpene-phenol resin may be added to the acrylic pressure-sensitive adhesive.

To prepare an acrylic pressure-sensitive adhesive,
An emulsion obtained by emulsifying a required monomer with a surfactant in an aqueous solution of a polymerization initiator such as ammonium persulfate is continuously added dropwise for polymerization. However, the polymerization form is not limited to this. The polymerization reaction conditions are appropriately selected mainly depending on the kind of the monomer.

As the rubber-based adhesive, rubber elasticity such as natural rubber, styrene-isoprene-based block copolymer, styrene-butadiene-based block copolymer, polyisoprene, polybutene, polyisobutylene, ethylene-vinyl acetate copolymer, etc. For 100 parts by weight of the body, for example, rosin resin, polyterpene resin, coumarone-indene resin,
20 to 200 parts by weight of a tackifier such as a petroleum-based resin or a terpene-phenol resin, and if necessary, a softening agent such as liquid polybutene, mineral oil, lanolin, liquid polyisoprene, or liquid polyacrylate: titanium oxide or the like. Filler: A material obtained by adding an appropriate amount of an antiaging agent such as butylhydroxytoluene is used.

The styrene-isoprene block copolymer and the styrene-butadiene block copolymer include a styrene-isoprene block copolymer, a styrene-isoprene-styrene block copolymer, and a styrene-butadiene block copolymer. Examples thereof include styrene-based thermoplastic elastomers such as polymer, styrene-butadiene-styrene / block copolymer, and styrene-ethylene-butylene-styrene / block copolymer.

The amount of the tackifier added is 100% rubber elastic body.
When the amount is less than 20 parts by weight, the internal condensation force of the adhesive is large and the adhesive force is insufficient, and when it exceeds 200 parts by weight, the internal condensation force of the adhesive is small and the adhesive causes cohesive failure. .

As the silicone-based pressure-sensitive adhesive, one having polydimethylsiloxane as a main component is used.

To form a pressure-sensitive adhesive layer on one side of a dyed film, a solution or emulsion containing a pressure-sensitive adhesive is usually applied to the white film-free inorganic film-containing film side of the dyed film, such as a comma coater or a top feed reverse coater. Directly apply and dry. In some cases, this pressure-sensitive adhesive layer is brought into close contact with a protective release paper. The thickness of the pressure-sensitive adhesive layer varies depending on the purpose of use, but is usually in the range of 5 to 100 μm.

[0043]

【Example】

Example 1 A two-layer PET film consisting of a layer containing a white inorganic compound and a layer not containing a white inorganic compound was a film "Crisper" manufactured by Toyobo Co., Ltd. (thickness 25 μm, G1211, width 10).
00 mm, fine pores 0.2-2 μm, density 1.1 g / c
m ³ ) was prepared. This two-layer PET film is manufactured as follows.

To 100 parts by weight of a polyethylene terephthalate resin, 4 parts by weight of titanium dioxide and 8 parts by weight of a pore assistant (Type HRM manufactured by Denki Kagaku Co., Ltd., second-order transition temperature 95 ° C.) were added, and the resin was added. Melt kneading was performed to uniformly disperse titanium dioxide and a pore assistant in the resin. The obtained kneaded product and the PET resin containing neither a white inorganic compound nor a vacancy aid were extruded using a melt extruder equipped with a T-type die to obtain an unstretched film having a layer ratio of 10: 1. The obtained unstretched film was passed between rolls with different peripheral speeds, stretched in the length direction, and further stretched in the width direction using a tenter. Thus, a stretched film having a thickness of 25 μm and a width of 1000 mm was produced and once wound into a roll. This film was white and had a total light transmittance of 20%.

While unwinding this two-layer PET film from a roll, it was immersed in warm water containing 2 g / liter of a nonionic surfactant at a temperature of 60 ° C. for 1 minute to preliminarily wash both sides of the film, and after drying, the film was dried. It was rolled up.

Disperse dye (Samaron Golden manufactured by Hoechst
Yellow HGL 2g / l, BASF Celliton
Orange R 1g / l and ICI Disper
solRed DB 1.5g / l mixed dye) to leveling agent (BASF's Uniperol W, 1g / l) and accelerating agent (Nichika Chemical's CL-511, 5g / l)
Was added and the resulting aqueous solution was heated to a temperature of 98 ° C. to prepare a constant temperature dyeing bath having a uniform concentration.

Next, the above-mentioned pre-cleaning film was fed out from the roll stand into this dyeing bath and the accumulated time in the dyeing bath was 3 times.
After soaking for 0 minute, the dye solution adhering to both surfaces of the film was wiped off, and the dyed film was wound again into a roll.

Finally, the dyed film was unrolled from the roll and immersed in warm water at a temperature of 60 ° C. for 1 minute to wash away excess dye, leveling agent, and accelerating agent adhering to the surface of the dyed film. Then, this film was dried with hot air at 130 ° C. for 1 minute and then wound into a roll. Thus, a dyed film composed of a two-layer PET film was manufactured.

In this dyed film, the light wavelength region 300
The spectral light transmittance at 520 nm was 0.1% or less. Further, the spectral light transmittance at 580 nm was 0.5% or less. Furthermore, the tensile strength of this film is
When measured in accordance with S C2318, 7.
5 kg / mm ^2, it was 6.5 kg / mm ² in the transverse direction.

A solvent-type acrylic pressure-sensitive adhesive was directly applied to a white inorganic compound-free film side of this dyed two-layer film using a comma coater and dried to form a pressure-sensitive adhesive layer of 15 μm. The thickness of the pressure-sensitive adhesive layer was uniform throughout, and there was no discoloration of the dyed film.

The light-shielding pressure-sensitive adhesive film thus obtained is
In addition to having the performance as a photosensitive masking material for photoengraving, even if this masking material was placed on an original document, the original could be seen through and the photoengraving work could be facilitated. Further, using this light-shielding pressure-sensitive adhesive film, ordinary plate making work and baking work (90 V, 15 seconds) could be easily performed.

Example 2 A dyed two-layer PET film was produced in the same manner as in Example 1 except that the preliminary washing film was immersed in a constant temperature dyeing bath at a temperature of 98 ° C. for a cumulative time of 60 minutes in the dyeing bath.

The spectral light transmittance of this dyed two-layer PET film in the light wavelength region of 300 to 560 nm was 0.1% or less. The spectral light transmittance at 580 nm is 0.5%.
It was below. In addition, the tensile strength of the film is JI
When measured in accordance with S C2318, 7.
5 kg / mm ^2, it was 6.5 kg / mm ² in the transverse direction.

A solvent-type acrylic pressure-sensitive adhesive was applied directly to the white inorganic compound-free film side of this dyed two-layer film using a comma coater and dried to form a pressure-sensitive adhesive layer of 15 μm. The thickness of the pressure-sensitive adhesive layer was uniform throughout, and there was no discoloration of the dyed film.

Comparative Example 1 As a PET film containing neither a white inorganic compound nor a vacancy aid, a transparent PET film having a spectral light transmittance of 88% in a light wavelength region of 550 nm (T manufactured by Dia foil Co., Ltd.) was used.
100 # 25) was prepared. A dyed film was produced in the same manner as in Example 1 except that this transparent PET film (T100 # 25 manufactured by Diamond Foil) was used.

An acrylic pressure-sensitive adhesive layer was formed on this dyed film in the same manner as in Example 1 to obtain a light-shielding pressure-sensitive adhesive sheet.

Comparative Example 2 The transparent PET film used in Comparative Example 1 was dyed in the same manner as in Example 2 to produce a dyed film.

An acrylic pressure-sensitive adhesive layer was formed on this dyed film in the same manner as in Example 1 to obtain a light-shielding pressure-sensitive adhesive sheet.

Comparative Example 3 A constant temperature dyeing bath heated to 120 ° C. under pressure was prepared,
The same transparent PET film as used in Comparative Example 1 was immersed in the above dyeing bath in the same manner as in Example 2. Then, the water on the surface of the film was wiped off, and the film was instantaneously washed in a methyl ethyl ketone room temperature bath to remove the thermally decomposed insoluble matter such as oligomers formed. Then, the solvent is volatilized and washed with water to remove water-soluble deposits, and the temperature is 130 ° C.
The film was dried with hot air for 1 minute to obtain a roll-shaped dyed film.

The obtained dyed film has a light wavelength range of 300.
Spectral light transmittance of ~ 550 nm is 0.1% or less and 5
The spectral light transmittance of 80 nm is 0.5% or less, and it has the performance as a photosensitive masking material for photoengraving, and even if this masking material is placed on the original drawing, it can be seen through and can be used for photoengraving work. there were.

However, in such a pressurized high temperature dyeing, a large amount of equipment cost is required for the pressurized constant temperature dyeing bath. In addition, as described above, a large amount of thermally decomposable insoluble matter such as oligomers is generated from the PET film, and this is bonded to the dye or auxiliary agent and attached to the film surface. Therefore, in order to remove this insoluble matter, it is necessary to wash with an organic solvent such as methyl ethyl ketone, toluene, and ethyl acetate, which complicates the washing process and requires equipment to improve the danger of fire and the working environment. Therefore, there is a drawback that the economical efficiency is significantly reduced.

Further, thermal decomposition products such as oligomers also adhere to the dyeing bath, which increases the cost for washing the bath and causes the productivity to be remarkably reduced.

An acrylic pressure-sensitive adhesive layer was formed on this dyed film in the same manner as in Example 1 to obtain a light-shielding pressure-sensitive adhesive sheet.

Performance Evaluation For each of the dyed films obtained in Examples 1 and 2 and Comparative Examples 1 to 3, spectral light transmittance measurement results, light-shielding property, economic evaluation, and light-shielding pressure-sensitive adhesive film were evaluated for workability. The evaluation is summarized in Table 1.

[0065]

[Table 1] In the table, ◎ means excellent, ○ means good, Δ means good, and × means bad.

[0066]

Since the light-shielding pressure-sensitive adhesive sheet or tape according to the present invention is constructed as described above, the following remarkable effects are exhibited.

By adjusting the amount of addition of the white inorganic compound, it is possible to produce dyed films having different light-shielding properties and dyeing concentrations even under the same dyeing conditions, and it is possible to increase variations as a light-shielding adhesive film.

PET containing a white inorganic compound
Since the film is used, it can be dyed at a high temperature and in a short time at a low temperature and a normal pressure.

When the PET film contains fine pores, the dyeing effect is further enhanced.

Since the PET film contains a white inorganic compound, it has a surface matting effect. Further, when this light-shielding pressure-sensitive adhesive sheet or tape is used as a light-sensitive masking material for light-shielding a light-sensitive material in the field of printing such as photoengraving, there is no reflection by an indoor lamp in plate-making work in a bright room, and the work is performed efficiently. be able to.

Since the dyeing film is composed of a two-layer film, a light-shielding pressure-sensitive adhesive sheet or tape having great strength can be obtained.

Claims (1)

[Claims] 1. A light-shielding pressure-sensitive adhesive sheet or tape comprising a dyeing film and a transparent pressure-sensitive adhesive layer formed on one surface of the film, wherein the dyeing film contains a white inorganic compound and has numerous fine pores. A film obtained by dyeing a two-layer film of a polyethylene terephthalate film having the above and a polyethylene terephthalate film containing no white inorganic compound with a disperse dye, and substantially blocking light rays in the light wavelength region of 300 to 580 nm. A light-shielding pressure-sensitive adhesive sheet or tape, characterized in that the pressure-sensitive adhesive layer is provided on the white-layer inorganic compound-free film side of the two-layer film.