JP2003096410A - Adhesive sheet for surface protection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive sheet for a surface-protection use capable of imparting to the surface of an imaging paper for photograph, etc., outputted by a printer, excellent scratch resistance, water resistance and chemical resistance and improving the sharpness of the image. SOLUTION: The adhesive sheet is produced by laminating a releasing agent layer, a resin layer curable with ionizing radiation and having a thickness of 3-30 μm and a tacky adhesive layer of 1-30 μm thick on one surface of a plastic film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image paper such as a photograph output by a printer such as a color printer,
The present invention relates to a surface-protective pressure-sensitive adhesive sheet that is attached to the surface of a display panel or the like.

[0002]

2. Description of the Related Art In recent years, the technical innovation of color printers has been remarkable, and the sharpness and fineness of images such as photographs to be output are almost at the same level as those of conventional developed film photographs. However, an image paper such as a photograph output by a printer has a problem that its surface is inferior in scratch resistance, water resistance and chemical resistance as compared with a developed film photograph. Further, with the increase in the surface of image papers such as photographs output from printers, scratch resistance, water resistance, and chemical resistance are strongly demanded on the surface. In order to meet this demand, it is conceivable to attach a protective film to the surface of image paper such as photographs output by a printer. However, when a conventional protect film is attached to an image paper such as a photograph output by a printer, it is possible to impart water resistance and chemical resistance, but the scratch resistance is not sufficient, and the thickness of the image makes the image clear. There is a problem of decline.

[0003]

SUMMARY OF THE INVENTION The present invention is capable of imparting excellent scratch resistance, water resistance and chemical resistance to the surface of an image paper such as a photograph output by a printer, and further improves image sharpness. It is an object of the present invention to provide a pressure-sensitive adhesive sheet for surface protection.

[0004]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventor has found that a release agent layer, an ionizing radiation curable resin layer, on one surface of a plastic film,
And a structure in which the pressure-sensitive adhesive layer is sequentially laminated, the release agent layer-attached plastic film is used to form the ionizing radiation-curable resin layer, and the surface-protective pressure-sensitive adhesive sheet is easily attached to the adherend. It has been found that the above-mentioned problems can be solved by making the structure capable of peeling and by making the thickness of the ionizing radiation curable resin layer and the pressure-sensitive adhesive layer within a specific thin range, and has completed the present invention. That is, the present invention is
On one surface of the plastic film, a release agent layer, an ionizing radiation curable resin layer having a thickness of 3 to 30 μm, and a thickness of 1 to 3
A pressure-sensitive adhesive sheet for surface protection, comprising a pressure-sensitive adhesive layer having a thickness of 0 μm. The present invention also provides the pressure-sensitive adhesive sheet for surface protection, wherein the release agent layer contains an alkyd resin or a polyolefin resin.

Further, in the present invention, in the above pressure-sensitive adhesive sheet for surface protection, the ionizing radiation curable resin layer has a number average molecular weight of 30.
The present invention provides a pressure-sensitive adhesive sheet for surface protection, which is obtained by curing an ionizing radiation curable substance composed of a mixture of 00 or more bifunctional urethane (meth) acrylate and polyfunctional (meth) acrylate having 3 or more functional groups. . The present invention also provides the pressure-sensitive adhesive sheet for surface protection, wherein the surface of the release agent layer of the plastic film has fine irregularities.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the pressure-sensitive adhesive sheet for surface protection of the present invention, examples of the plastic film include polyethylene resins such as high density polyethylene, medium density polyethylene and low density polyethylene, polypropylene resins such as polypropylene, and polymethyl- Polyolefin resins such as 1-pentene / ethylene / cyclic olefin copolymer, ethylene-vinyl acetate copolymer, nylon-6, nylon-6,6, nylon-6,10, nylon-6,1
Polyamide resin such as 2, polyethylene terephthalate,
Polybutylene terephthalate, copolymers thereof, polyethylene naphthalate, polyester resin such as aliphatic polyester, polycarbonate resin, polystyrene resin, polyphenylene sulfide resin, polyvinyl chloride resin, polyimide, fluorine resin, or any of these Films such as copolymers, polymer blends, and polymer alloys can be used, but polyester resin and polyolefin resin films are preferably used. The thickness of the plastic film is not particularly limited, but is usually about 10 to 300 μm.

The release agent layer in the pressure-sensitive adhesive sheet for surface protection of the present invention is composed of a release agent. As a release agent,
Although various release agents can be used, examples include alkyd resins, silicone resins, polyolefin resins and the like. The release agents may be used alone or in combination of two or more. As the release agent, alkyd resin and polyolefin resin are preferable. Examples of the alkyd resin include a condensation polymer of glycerin and phthalic acid or phthalic anhydride (straight alkyd resin), and a modified alkyd resin which is a modified product of the straight alkyd resin. Examples of the modified alkyd resin include acrylic modified alkyd resin, rosin modified alkyd resin, phenol modified alkyd resin, and urethane modified alkyd resin. Among these, the alkyd resin is preferably an acrylic modified alkyd resin.

A silicone resin may be mixed with the alkyd resin. When the alkyd resin and the silicone resin are mixed and used, the mixing ratio of the alkyd resin is
70 to 95 mass% is preferable. As the polyolefin resin, polyethylene resin, polypropylene resin,
Examples thereof include ethylene-propylene copolymer resin and polybutene resin. Of these, polyethylene resin is preferred. The release agent layer usually has a thickness of 30 μm or less, and has a thickness of 0.
01 to 25 μm is preferable, and 0.1 to 20 μm is particularly preferable. If the release agent layer surface has a fine uneven shape, the surface of the ionizing radiation curable resin layer can also have a fine uneven shape, and when it is attached to an image paper such as a photograph,
It can be a matte type surface-protective pressure-sensitive adhesive sheet capable of matting the surface of an image such as a photograph. The surface roughness of the fine irregularities is preferably 0.15 to 0.5 μm in terms of center line average roughness (Ra), and 0.2 to 0.4 μm.
Is particularly preferable. As a method for making the surface of the release agent layer finely uneven, a method such as embossing the surface of the release agent layer or applying a thin release agent layer to the surface of the plastic film having the finely uneven surface is used. Is mentioned.

The ionizing radiation curable resin layer in the pressure-sensitive adhesive sheet for surface protection of the present invention can be formed by applying a curable composition containing an ionizing radiation curable substance and irradiating it with an ionizing radiation to cure it. The ionizing radiation-curable substance is a substance that is cured by irradiation with ionizing radiation, and examples thereof include unsaturated monomers, oligomers, resins, and compositions containing them. Specific examples thereof include polyfunctional radiation-curable acrylic compounds having two or more functional groups such as (meth) acrylate, urethane (meth) acrylate and polyester (meth) acrylate.
Examples of the (meth) acrylate include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, hexanediol di (meth) acrylate, and trimethylol. Ethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, Glyceryl tri (meth) acrylate, triallyl (meth) acrylate, bisphenol A ethylene oxide modified di (meth)
Acrylate and the like are preferred.

As the urethane (meth) acrylate,
Examples thereof include (meth) acrylate in which a (meth) acryloyl group is bonded to a polyol through a urethane bond, and examples thereof include a reaction product of a polyol, a diisocyanate, and a hydroxyl group-containing (meth) acrylate. Examples of the polyol include polyether polyol and polyester polyol, and the polyether polyol is preferable. Examples of polyols include aliphatic polyols and aromatic polyols, with aliphatic polyols being preferred. Examples of the diisocyanate include aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, and the like, and aliphatic diisocyanate and alicyclic diisocyanate are preferable. Hydroxyl group (meta)
Examples of the acrylate include hydroxyaryl (meth) acrylate, hydroxyalkyl (meth) acrylate, hydroxycycloalkyl (meth) acrylate, and the like, and hydroxyalkyl (meth) acrylate is preferable. Examples of the bifunctional urethane (meth) acrylate include those using diol as the polyol. The ionizing radiation curable substances may be used alone or in combination of two or more. If desired, a vinyl compound such as styrene or vinylpyrrolidone may be used in combination.

The ionizing radiation curable substance has a number average molecular weight of 3
A mixture of a bifunctional urethane (meth) acrylate of 000 or more and a polyfunctional (meth) acrylate having 3 or more functional groups is preferable. 10 to 200 polyfunctional (meth) acrylates having 3 or more functional groups per 100 parts by mass of a bifunctional urethane (meth) acrylate having a number average molecular weight of 3000 or more.
A mass part is preferable and a 20-150 mass part is especially preferable. The number average molecular weight of the bifunctional urethane (meth) acrylate is more preferably 3,000 to 20,000 and 4,000.
It is particularly preferably 10000. Moreover, 3-8 are preferable and, as for the number of functional groups of a polyfunctional (meth) acrylate whose number of functional groups is 3 or more, 3-6 are especially preferable. Specific examples of the polyfunctional (meth) acrylate having 3 or more functional groups include trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth). Examples thereof include acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and glyceryl tri (meth) acrylate. The curable composition includes a photopolymerization initiator such as acetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, and benzoin methyl ether. , Toluene, 1
A solvent such as methoxy-2-propanol, isopropyl alcohol, methyl isobutyl ketone may be contained. The surface hardness of the ionizing radiation curable resin layer is preferably such that the pencil hardness is H or higher. Further, the ionizing radiation curable resin layer preferably has no tack on the surface,
Specifically, the probe tack (JIS Z0237) is preferably less than 10 g / φ5 mm, more preferably less than 1 g / φ5 mm, and particularly preferably 0 g / φ5 mm. The thickness of the ionizing radiation curable resin layer is 3 to 30 μm, preferably 5 to 20 μm.

In the present invention, the ionizing radiation curable resin layer preferably has transparency in order to improve the sharpness of the image. Ionizing radiation curable resin layer, the surface of the release agent layer usually provided on the surface of the plastic film, a curable composition containing an ionizing radiation curable substance is applied, the coating film is irradiated with ionizing radiation, It is formed by curing. Ionizing radiation includes ionizing radiation such as electron beams and ultraviolet rays. The irradiation dose of ionizing radiation is not particularly limited as long as the curable substance is cured, but, for example,
In the case of UV irradiation, the illuminance is usually 5 by a UV lamp.
0-300 mW / cm ² , light intensity 30-800 mJ / cm
Irradiate in the range of ² .

In the present invention, an adhesive layer is provided on the surface of the ionizing radiation curable resin layer. The adhesive used in the adhesive layer is, for example, a natural rubber adhesive, a synthetic rubber adhesive, an acrylic resin adhesive, a polyvinyl ether resin adhesive, a urethane resin adhesive, a silicone resin adhesive, etc. Is mentioned. Specific examples of the synthetic rubber-based adhesive include styrene-butadiene rubber, polyisobutylene rubber, isobutylene-isoprene rubber, isoprene rubber, styrene-isoprene block copolymer, styrene-butadiene block copolymer, styrene-ethylene-butylene block. Examples thereof include copolymers and ethylene-vinyl acetate thermoplastic elastomers. Specific examples of the acrylic resin-based adhesive include acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, acrylonitrile. And homopolymers or copolymers thereof. Specific examples of the polyvinyl ether resin-based adhesive include polyvinyl ether and polyvinyl isobutyl ether. Specific examples of the silicone resin-based adhesive include dimethylpolysiloxane. These adhesives may be used alone or in combination of 2
A combination of two or more species can be used.

If desired, the pressure-sensitive adhesive layer may contain a tackifier, a softening agent, an antiaging agent, a filler, a coloring agent such as a dye or a pigment, and the like. Examples of the tackifier include rosin resins, terpene phenol resins, terpene resins, aromatic hydrocarbon-modified terpene resins, petroleum resins, coumarone / indene resins, styrene resins, phenol resins, and xylene resins. Examples of the softening agent include process oil, liquid rubber and plasticizer. Examples of the filler include silica, talc, clay, calcium carbonate and the like. The thickness of the adhesive layer is 1 to
It is 30 μm, preferably 2 to 10 μm.

The pressure-sensitive adhesive layer may be formed by directly coating the pressure-sensitive adhesive on the ionizing radiation curable resin layer, or by coating the pressure-sensitive adhesive on the release agent layer surface of the release film and drying the pressure-sensitive adhesive layer to form a pressure-sensitive adhesive layer. It may be attached to a plastic film provided with an ionizing radiation curable resin layer. The method for forming the pressure-sensitive adhesive layer may be various methods without particular limitation,
Examples thereof include an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a curtain coater, a die coater, a knife coater, a screen coater, a Meyer bar coater, and a kiss coater. In the present invention, the pressure-sensitive adhesive layer preferably has transparency in order to improve the sharpness of the image.

The surface of the pressure-sensitive adhesive layer may be covered with a release film. Further, without using the release film, the release property may be imparted by applying a release agent to the surface of the plastic film opposite to the release agent layer, and the adhesive sheet may be rolled and stored. In this way, the surface of the pressure-sensitive adhesive layer can be protected. As the release film, various release films can be used, for example, films made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene and polyarylate, polyethylene laminated paper, polypropylene laminated paper, clay coat. It is possible to use, as a base material, various paper materials such as paper, resin-coated paper, glassine paper, and the like, the surface of which is joined to the pressure-sensitive adhesive layer and which has been subjected to a release treatment if necessary. In this case, as a typical example of the release treatment, formation of a release agent layer made of a release agent such as a silicone-based resin, a long-chain alkyl-based resin, or a fluororesin can be mentioned. The thickness of the release film is not particularly limited and may be appropriately selected.

When the pressure-sensitive adhesive sheet for surface protection of the present invention is applied to an adherend, if the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet is covered with a release film, the release film is peeled off and the pressure-sensitive adhesive layer is removed. Can be carried out by closely adhering to the surface of the adherend. After attaching the surface protection adhesive sheet to the adherend, peel it off at the interface between the ionizing radiation-curable resin layer and the release agent layer, remove the plastic film with the release agent layer, and cure the ionizing radiation on the adherend. By making the resin layer and the pressure-sensitive adhesive layer adhere to each other, the ionizing radiation curable resin layer can be formed on the surface of the adherend.

[0018]

EXAMPLES Next, the present invention will be specifically described by way of examples. However, the present invention is not limited to these examples. The surface roughness (Ra) and probe tack were measured using the following devices. Surface roughness: Surface roughness measuring device SAS-2010 type (manufactured by Meishing Machinery Co., Ltd.) Probe tack: Probe tack tester (manufactured by Rigaku Kogyo KK)

(Example 1) Bifunctional urethane acrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name "UF-503LN",
Number average molecular weight 4900, solid content concentration 70% by mass) 100
100 parts by mass of light and pentaerythritol triacrylate (manufactured by Toagosei Kagaku Kogyo Co., Ltd., product name "Aronix M-30", functional group number 3, solid content concentration 100% by mass) as a UV-curable polyfunctional acrylate. As a polymerization initiator, 2-methyl-1- [4- (methylthio)
Phenyl] -2-morpholinopropan-1-one (manufactured by Ciba Specialty Chemicals Co., Ltd., product name “Irgacure 907”) is mixed with 6.8 parts by mass, and toluene is further mixed as a diluting solvent to obtain a solid. 50 minutes
It adjusted to the mass% and the curable composition was obtained. Next, a process film (manufactured by Lintec Co., Ltd., product) in which the surface of a polyethylene terephthalate film (thickness 38 μm) is coated with an acrylic modified alkyd resin as a release agent to form an alkyd resin layer (thickness 0.2 μm) Name "PET3
8AL-5 ″) on the surface of the alkyd resin layer so that the thickness of the curable composition after curing may be 10 μm. 16 and then dried at 80 ° C for 1 minute. Then, ultraviolet rays (illuminance 120 mW / cm ² , light amount 300 mJ
/ Cm ² ) to irradiate the resin to form an ultraviolet curable resin layer.
The probe tack on the surface of the UV curable resin layer is 0g / φ
It was 5 mm. Next, a release film obtained by applying a silicone resin to a polyethylene terephthalate film (manufactured by Lintec Co., Ltd., product name "SP-PET3811",
An acrylic pressure-sensitive adhesive (manufactured by Lintec Co., Ltd., product name “PA-T1”) was applied to the surface having a thickness of 38 μm to form a film having a pressure-sensitive adhesive layer (thickness of 5 μm) on the pressure-sensitive adhesive layer surface. Then, it was attached to the ultraviolet curable resin layer to prepare a pressure-sensitive adhesive sheet for surface protection.

(Example 2) In Example 1, the product name "UF-803T" was used as the bifunctional urethane acrylate.
N "(manufactured by Kyoeisha Chemical Co., Ltd., number average molecular weight 8200, solid content concentration 70 mass%) was used in the same manner as in Example 1 to prepare a pressure-sensitive adhesive sheet for surface protection. The probe tack on the surface of the ultraviolet curable resin layer was 0 g / φ5 mm.

(Example 3) Bifunctional urethane acrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name "UF-503LN",
Number average molecular weight 4900, solid content concentration 70% by mass) 100
35 parts by mass of UV-curable polyfunctional acrylate (manufactured by Nippon Kayaku Co., Ltd., product name "KAYARAD DPHA", mixture of 5 functional groups and 6 functional groups, solid content concentration 100% by mass) and photopolymerization start Agent (Ciba Specialty Chemicals Co., Ltd., product name "IRGACURE 90"
7 "(supra)) 4.2 parts by mass and further mixed solvent of 1-methoxy-2-propanol and methyl isobutyl ketone (mixing mass ratio = 1/1) as a diluting solvent to obtain a solid content concentration. Was adjusted to 50% by mass to obtain a curable composition. Polyethylene terephthalate film (thickness 38
(μm) surface is coated with polyethylene resin,
Further, a process film (manufactured by Lintec Co., Ltd., product name “PET38NA”) having a polyethylene resin layer (thickness 20 μm) that has been embossed, surface roughness Ra =
0.2) on the surface of the polyethylene resin layer so that the thickness after curing the curable composition is 10 μm. It was coated with 16, after drying under 1 minute at 80 ° C., which UV (illuminance 120 mW / cm ^2, light quantity 300mJ
/ Cm ² ) to irradiate the resin to form an ultraviolet curable resin layer.
The probe tack on the surface of the UV curable resin layer is 0g / φ
It was 5 mm. Release film (manufactured by Lintec Co., Ltd.,
An acrylic pressure-sensitive adhesive (manufactured by Lintec Co., Ltd., product name "PA-T1") is applied to the surface of the product name "SP-PET3811", thickness 38 μm), and the pressure-sensitive adhesive layer (thickness 2 μm)
The film on which was formed was adhered to the ultraviolet-curable resin layer on the pressure-sensitive adhesive layer side to prepare a pressure-sensitive adhesive sheet for surface protection.

(Comparative Example 1) Meyer bar No. 1 was coated on the surface of a polyethylene terephthalate film (thickness: 50 μm) so that the curable composition used in Example 1 had a thickness of 10 μm after curing. After being applied at 16, dried at 80 ° C. for 1 minute, this was irradiated with ultraviolet rays (illuminance: 120 mW / cm ² , light intensity: 300 mJ / cm ² ) to form an ultraviolet curable resin layer. An acrylic pressure-sensitive adhesive (manufactured by Lintec Co., Ltd., product name “PA-T1”) was applied to the surface of the polyethylene terephthalate film on which the ultraviolet-curing resin layer was formed, on the side opposite to the ultraviolet-curing resin layer, and the pressure-sensitive adhesive layer ( Thickness 5μ
m) is formed, and a release film (manufactured by Lintec Co., Ltd., product name “SP-PET381” is further formed on the surface of the pressure-sensitive adhesive layer.
1 ", thickness 38 µm) were laminated to prepare a surface-protective pressure-sensitive adhesive sheet.

Comparative Example 2 In Comparative Example 1, as the curable composition, ultraviolet curable polyfunctional acrylate (pentaerythritol triacrylate) was mixed with toluene as a diluting solvent to adjust the solid content concentration to 50 mass%. A pressure-sensitive adhesive sheet for surface protection was prepared in the same manner as in Comparative Example 1 except that the curable composition was used.

(Performance Evaluation) The pressure-sensitive adhesive sheets for surface protection prepared in Examples and Comparative Examples were evaluated for performance by the following evaluation methods, and the results are shown in Table 1. <Bending resistance> The release film of the pressure-sensitive adhesive sheet for surface protection is peeled off, and the UV curable resin layer is on the outside, and the diameter is 10 mm.
The pressure-sensitive adhesive sheet for surface protection of Example was peeled off the process film and visually observed for the occurrence of cracks, and evaluated according to the following criteria. ◯: No cracks were generated. X: Cracks were generated. <Visual clarity> A pressure-sensitive adhesive sheet for surface protection was peeled off from the surface of the image side of color photographic paper printed with an inkjet color printer, and then the adhesive layer was applied. Then, the surface protection pressure-sensitive adhesive sheets of Examples were peeled off the process film, and after the process film was peeled off, the sharpness (shading of color etc.) of the photographic image when visually observed from an angle of 60 ° was sensory-evaluated. ○: Good sharpness ×: Poor sharpness

<Surface gloss> Color photo paper printed by an inkjet color printer (60 ° gloss = 3
On the surface of the image side of 8), after peeling off the release film, the pressure-sensitive adhesive sheet for adhesion is pasted with the pressure-sensitive adhesive layer, and then the surface-protective pressure-sensitive adhesive sheet of the example is UV cured after peeling the process film. The 60 ° glossiness of the surface of the resin layer is determined by JIS
According to K7105, it was measured using a gloss meter (manufactured by Nippon Denshoku Industries Co., Ltd., trade name "VG 2000"). <Total light transmittance> Peel off the process film and release film of the pressure-sensitive adhesive sheet for surface protection, and use a haze meter (Nippon Denshoku Industries Co., Ltd., trade name "NDH 2000") to measure the total light transmittance according to JIS K7105. It was measured.

<Scratch resistance> The peeling film of the pressure-sensitive adhesive sheet for surface protection is peeled off, the pressure-sensitive adhesive layer is laminated on the glass plate, and then the pressure-sensitive adhesive sheet for surface protection of the example is peeled off the process film, and then the ultraviolet curable resin is used. Steel wool # 00 on the layer surface
After being rubbed with a load of 9.8 × 10 ⁻³ N / mm ² at 00, it was visually observed and evaluated according to the following criteria. ◯: No scratch X: Scratch <Pencil hardness> The surface of the UV-curable resin layer of the pressure-sensitive adhesive sheet for surface protection was scratched according to the hand scraping method (JIS K5400).
The pencil hardness was measured.

[0027]

[Table 1]

The surface of color photographic paper has a 60 ° gloss of 38.
And low. When the pressure-sensitive adhesive sheet for surface protection of the example is attached to this color photographic paper and the process film is peeled off, the glossiness increases and the texture becomes good. However, when the pressure-sensitive adhesive sheet for surface protection of Comparative Example is attached, the glossiness increases too much and the sharpness is rather lowered due to reflected light.

[0029]

The surface-protective pressure-sensitive adhesive sheet of the present invention can impart excellent water resistance, chemical resistance and scratch resistance to the surface of image paper such as photographs output by a printer, and further provides clear images. Can be improved.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme coat (reference) G09F 3/02 G09F 3/02 BF term (reference) 4F100 AK01A AK01C AK03B AK25C AK25G AK41B AK42 AK52 AR00C BA03 BA07 BA10A BA10C EH46 EH462 EJ54 EJ542 GB41 JA07C JB07 JB14C JK14 JL14B YY00C 4J004 AA04 AA05 AA06 AA08 AA10 AA11 AA14 AB01 CA03 CA04 CA05 CA06 CC03 JA05 NA32 NA01 FA11 NA17 FA01 NA01 FA01 FA05 FA07 FA04 FA04 FA04 FA04 FA04 FA04 FA04 FA04 FA04 4 PA17 PB09 PC08 4J040 FA132 FA291 JA09 JB07 LA01

Claims (4)

[Claims] 1. A release agent layer, an ionizing radiation curable resin layer having a thickness of 3 to 30 μm, and an adhesive layer having a thickness of 1 to 30 μm are laminated on one surface of a plastic film. Adhesive sheet for surface protection. 2. The pressure-sensitive adhesive sheet for surface protection according to claim 1, wherein the release agent layer contains an alkyd resin or a polyolefin resin. 3. An ionizing radiation curable resin layer having a number average molecular weight of 30.
The surface-protective pressure-sensitive adhesive according to claim 1 or 2, which is obtained by curing an ionizing radiation-curable substance consisting of a mixture of 00 or more bifunctional urethane (meth) acrylate and polyfunctional (meth) acrylate having 3 or more functional groups. Sheet. 4. The pressure-sensitive adhesive sheet for surface protection according to claim 1, wherein the surface of the release agent layer has fine irregularities.