JPH06171051A - Sheet-like support - Google Patents

Abstract

PURPOSE:To contrive to realize the sheet-like support, which is too flexible to crack even when being folded, has high glossy feeling, surface flatness and water resistance by a method wherein number-average molecular weight of urethane oligomer of electron-radiation-curing unsaturated organic compound measured with GPC and acrylic equivalent represented by a formula are brought into the specified ranges. CONSTITUTION:The sheet-like support concerned has sheet-like base and surface resin covering layer, which is formed at least on one side of the sheet-like base and made of cured body of composition mainly containing electron- radiation-curing unsaturated organic compound. The unsaturated organic compound contains acryloylmorpholine and urethane oligomer. Further, urethane oligomer has acryloil group at its terminal, its number-average molecular weight measured with gel permeation chromatography (GPC) is 2,000-12,000 in polystyrene equivalent and its acrylic equivalent represented by the formula A/B, in which A is the number-average molecular weight and B is the number of acryloyl groups, of 1,000-6,000.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a sheet-like support. More specifically, the present invention provides
A sheet-like support having a surface resin coating layer on the surface of a sheet-like substrate, which is a cured product of a composition containing as a main component a resin that cures by electron beam irradiation (hereinafter, this phenomenon is referred to as electron beam curability) It is a thing. In particular, release paper, glossy paper, metal vapor-deposited label support, paper printed matter, laminated paper, coated paper, thermal paper, pressure-sensitive paper, adhesive paper, which has been provided with smoothness, water resistance, and high gloss on the surface of the support, The present invention relates to a sheet-shaped support used for manufacturing decorative paper and the like.

[0002]

2. Description of the Related Art Today, a sheet-like support having a resin coating layer on the surface of the substrate is widely used to make full use of the characteristics of a sheet-like substrate such as paper, and is used in every corner of life. Has penetrated up to. That is, as a composite material that makes the best use of the characteristics of each of the paper and the resin sheet, for the purpose of improving the physical properties of the paper base material, and for giving a good-looking glossy feeling, and also for roughening the background of the paper base material. Many sheet-like supports are used for the purpose of smoothing. The field of application is also extensive, including information, packaging, and industrial base materials.

Conventionally, in order to form such a surface resin coating layer on paper, a resin composition prepared by appropriately selecting and blending various resins is dispersed or dissolved in water or a solvent, coated on a sheet-shaped substrate and dried. Widely used are a method of completing the above, a method of melting and laminating a resin on a sheet-shaped substrate, a method of applying hot melt, and the like.

However, in the method of dispersing and coating and drying the above resin composition in water or a solvent, the larger the coating amount of the resin and the higher the processing speed, the larger the drying and melting facilities are required. Therefore, there is a problem that the installation area and the thermal energy required for drying and melting become large. Further, in the coating method using a solvent, it is necessary to collect the solvent evaporated in the drying step, but it is difficult to collect all of the solvent, which is not preferable in terms of environmental measures.

Under these circumstances, in recent years, a resin composition containing an unsaturated organic compound as a main component is applied to a sheet-like base material, which is irradiated with an electron beam to cure the resin composition to form a resin coating layer. Then, a method for producing a sheet-like support using a so-called electron beam curing technique for obtaining a sheet-like support has come to be used. According to this method, there is an advantage that drying and melting equipment is not required, the apparatus is compact, and the solvent is not released to the atmosphere.

The method of curing a resin composition by using an electron beam curing technique involves irradiating an electron beam having high energy and penetrating the electron beam into the coating layer to cure the resin composition. The resin coating layer obtained is hard, has a high gloss on the surface, and is also excellent in water resistance. However, since the resin coating layer is hard, the sheet-shaped support is poor in flexibility as a whole and has a defect that the resin coating layer is cracked when it is bent.

[0007]

The present invention solves the above problems and provides a sheet-like support having a surface resin coating layer composed of a cured product of a composition containing as a main component a resin curable by electron beam irradiation. In the body, it has flexibility that does not generate cracks even when bent, and has a high glossy feeling and surface smoothness,
It is intended to provide a sheet-like support having both water resistance.

[0008]

The sheet-like support of the present invention mainly comprises a sheet-like substrate and an unsaturated organic compound which is formed on at least one surface of the sheet-like substrate and can be cured by electron beam irradiation. And a surface resin coating layer formed of a cured product of a composition containing as a component, the unsaturated organic compound contains acryloylmorpholine and a urethane oligomer, and the urethane oligomer has the following characteristics: 1) an acryloyl group at a terminal. 2) The number average molecular weight measured by gel permeation chromatography (GPC) is 2000 to 1 in terms of polystyrene.
2000, 3) The acrylic equivalent represented by the following formula (1) is 1000 to
Acrylic equivalent = A / B (1) A: number average molecular weight measured by GPC (polystyrene conversion) B: number of acryloyl groups in one urethane oligomer molecule, sheet-like support It is the body.

Generally, a sheet-shaped support having a surface resin coating layer made of a cured product of an electron beam curable resin has a compact manufacturing facility, does not require the use of a solvent, and heats the sheet-shaped substrate. Since it does not occur, it has excellent dimensional stability, and has the advantage that a large amount of pigment can be added. However, on the other hand, the surface resin coating layer is hard and has a quality defect that a large crack is generated when the sheet support is bent.

Conventionally, urethane acrylate has been used to form a flexible coating film, but the molecular weight of the oligomer is lowered to reduce the viscosity of the paint, or diluted with an acrylate monomer having a relatively low molecular weight. It is generally done. However, a decrease in the molecular weight of the oligomer leads to an increase in the crosslink density and hardens the resin cured layer.
The use of diluting monomer also reduces flexibility.

As a result of various studies on the solution to the above problems, the inventors of the present invention have solved the above problems of flexibility by incorporating a specific urethane oligomer and acryloylmorpholine as an electron beam-curable unsaturated organic compound. As a result, they have found that cracks that occur when a sheet-shaped support is bent can be completely prevented, and have completed the present invention.

The electron beam curable coating composition for forming the resin coating layer used in the present invention comprises a urethane oligomer and acryloylmorpholine. The urethane oligomer has an acryloyl group at the terminal,
As for the molecular weight, the number average molecular weight determined by GPC is 2000 to 12000 in terms of polystyrene, and the acrylic equivalent determined by the above formula (1) is 1000 to 600.
Must be 0.

If the molecular weight exceeds 12000, the viscosity of the resin will be high and the coating property will be poor, and if it is less than 2000, the crosslinking density will be high and the resin will be hard and the flexibility will be poor.
On the other hand, when the acrylic equivalent exceeds 6000, the curing speed becomes slow, and sufficient flexibility of the coating film cannot be obtained.
If it is less than 0, the crosslink density becomes high, and the resin becomes hard and the flexibility becomes poor.

The content of the urethane oligomer in the resin coating layer-forming coating composition is preferably 20 to 70% by weight, more preferably 30 to 60% by weight. When the content of the urethane oligomer is 70% or more, the viscosity is remarkably increased and the coating performance is deteriorated, and when it is 20% or less, the curing speed is lowered and sufficient flexibility of the coating film may not be obtained.

Acryloylmorpholine acts as a reactive diluent in the coating composition, has a fast curing rate and makes the coating film toughened. The content of the acryloylmorpholine is 10% by weight in the resin coating layer forming coating composition.
It is preferably contained in the above amount, and more preferably 20% by weight or more. If it is less than 10% by weight, the coating film may not be imparted with sufficient toughness and flexibility.

The electron beam curable coating composition used in the present invention may optionally contain the following electron beam curable unsaturated organic compound. Such organic compounds are
A monofunctional acrylic system having a terminal group that generates a radical by electron beam irradiation and undergoes a crosslinking reaction, and has, for example, one double bond selected from an acryloyl group, a methacryloyl group, and a vinyl group in one molecule. Monomers, monofunctional methacrylic monomers, monofunctional vinyl monomers, and at least two or more acryloyl groups in one molecule,
It is selected from a polyfunctional acrylic monomer having a double bond selected from a methacryloyl group and a vinyl group, a methacrylic monomer, and a vinyl monomer.

More specifically, the monofunctional acrylic, methacrylic, and vinyl monomers are styrene, N-vinylpyrrolidone, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, isooctyl acrylate, lauryl acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, cyclohexyl acrylate, cyclohexyl methacrylate, benzyl acrylate, Isobornyl acrylate, ethylene oxide modified phenoxy acrylate, N, - dimethylaminoethyl acrylate, it is preferably selected from an alkyl phenoxy polyethylene glycol acrylate.

Polyfunctional acrylic, methacrylic, and vinyl monomers, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6
-Hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol diacrylate, diethylene glycol diacrylate,
It is preferably selected from triethylene glycol diacrylate, neopentyl glycol diacrylate diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, divinylbenzene and the like.

The organic compound contained in the coating composition of the present invention is, of course, not limited to the above, but it is particularly preferable to use a monofunctional monomer when imparting plasticity to the resin coating layer.

The coating amount of the resin coating layer of the present invention is 1 to 60.
It is preferably g / m ² . If the coating amount is less than 1 g / m ^2, it is difficult to sufficiently exert the effects of the present invention, and problems such as pinholes may occur during the coating process. If the coating amount exceeds 60 g / m ^2. It may not be practical in terms of cost.

The electron beam curable coating composition used in the present invention may contain a pigment, if desired. As the pigment, titanium dioxide (anatase type and rutile type), barium sulfate, calcium carbonate, aluminum oxide, zinc oxide, magnesium oxide, magnesium hydroxide, kaolin, talc, clay and the like can all be used. The content of the pigment is preferably 80% by weight or less of the total solid content of the coating composition. If it exceeds 80% by weight, the flexibility of the resin coating layer obtained is reduced,
May cause film cracking.

To disperse the pigment in the electron beam curable coating composition, a three roll mill (three roll mill), a two roll mill (two roll mill), a cowles dissolver,
A homomixer, a sand grinder, a planetary mixer, an ultrasonic disperser, etc. can be used.

The method of applying the resin composition to the surface of the molding surface or the surface of a sheet-shaped substrate such as paper or plastic is, for example, a bar coating method, a blade coating method, a squeeze coating method, an air knife coating method, a roll coating method. Any of the gravure coating method, the transfer coating method and the like may be used. For this purpose, a fountain coater or slit die coater system can be used. Especially when the surface of a metal drum is used as a molding surface, a roll coating method using a rubber roll or an offset gravure coating method is used in order to prevent scratches on the molding surface. Fountain coater and slit die coater methods are advantageously used.

The electron beam accelerator used for the electron beam irradiation is not particularly limited in its system, and for example, an electron beam irradiation device such as a van de Graaff scanning system, a double scanning system, or a curtain beam system can be used. However, among them, the curtain beam type, which is relatively inexpensive and can obtain a large output, is advantageously used. The acceleration voltage at the time of electron beam irradiation is preferably 100 to 300 kv, and the absorbed dose is 0.1 to 6 Mra.
preferably d, 0. 5-5 Mrad is particularly preferred.

The oxygen concentration in the atmosphere during electron beam irradiation is preferably 500 ppm or less. Oxygen concentration is 5
If it exceeds 00 ppm, oxygen may act as a retarder for the polymerization reaction and the resin composition may be insufficiently cured. However, in order to obtain the surface smoothness of the electron beam curable sheet-like support, when pressing a suitable molding surface such as a metal drum or a plastic film against the electron beam curing coating liquid applied on the paper substrate, , The electron beam curing coating liquid does not come into direct contact with air during electron beam irradiation, and therefore it is not necessary to particularly reduce the oxygen concentration in the atmosphere during electron beam irradiation, but the purpose is to suppress ozone generation due to electron beam irradiation. Of course, there is no problem in using the inert gas for the purpose of cooling the window that generates heat when the electron beam passes through.

The sheet-like base material used in the present invention is not particularly limited, but base paper containing natural pulp as a main component is advantageously used.

As the base paper whose main component is natural pulp,
A base paper made of wood pulp such as hardwood pulp, softwood pulp, and mixed hardwood softwood pulp, or base paper made of bleached pulp such as kraft pulp, sulfite pulp, soda pulp and the like can be used. Further, it is possible to use a base paper produced from synthetic pulp or pulp containing synthetic fibers.

In the present invention, the base paper used as the sheet-shaped base material has various usual additives such as a dry paper strength enhancer (cationized starch, cationized polyacrylamide,
And anionic polyacrylamide), sizing agents (such as fatty acid salts, rosins, maleated rosins, cationic sizing agents, and reactive sizing agents), fillers (clay,
Talc, kaolin, calcium carbonate, magnesium hydroxide, magnesium oxide, etc.), wet strength agents (such as melamine resin and epoxidized polyamide resin), fixing agents (such as aluminum sulfate and cationized starch), pH adjusting agents One or more types (such as caustic soda and sodium carbonate) can be included.

Further, at least one kind of water-soluble polymer additive, surface sizing agent, inorganic electrolyte, hygroscopic substance, pigment, pH adjusting agent, dye, antistatic agent, polyvinyl alcohol, carboxy-modified polyvinyl alcohol, etc. may be used. The processing liquid to be contained may be tab size or size pressed.

Further, as the sheet-shaped substrate, a plastic film or so-called synthetic paper can be used. Further, a film formed by a melt extrusion method of a thermoplastic resin composition containing a polyolefin resin such as polypropylene resin or polyethylene resin can also be used as a sheet-shaped substrate.

If necessary, the plastic film or synthetic paper used as the sheet-shaped substrate may contain pigments (clay, talc, kaolin, calcium carbonate, titanium dioxide, magnesium hydroxide, etc.) and dispersants (zinc stearate). Such as metal soaps and various surfactants), colored pigments, and the like.

Further, in the sheet-shaped support of the present invention, the surface opposite to the surface on which the resin coating layer is formed can also be coated with the resin composition. In this case, the resin coating layer may be a resin composition that is cured by electron beam irradiation,
A resin coating layer applied by another method, for example, a coating layer of a resin composition containing a water-soluble resin as a main component, a coating layer of a resin composition containing a solvent-based resin as a main component, or a thermoplastic resin as a main component. It may be a coating layer obtained by applying a resin composition as a component by a melt extrusion method.

[0033]

EXAMPLES The constitution and effects of the present invention will be further described below with reference to examples, but of course the present invention is not limited to these modes. Example 1 A mixture having the following composition was mixed and dispersed for 1 hour with a paint conditioner to prepare a coating composition for forming a resin coating layer (composition 1). This composition was applied onto one surface of a paper substrate having a basis weight of 100 g / m ² using a wire bar so that the coating amount after curing would be 25 g / m ² , and this coating layer was used as a molding surface. Press on the surface of the chrome-plated metal plate to accelerate from the back surface of the paper substrate: 250
kv, absorbed dose: electron beam irradiation under the conditions of 2 Mrad to cure the coating layer to form a surface resin coating layer integrated with the paper substrate, and the sheet-like support thus obtained is cured from the metal plate surface to a resin cured layer. Was peeled off.

[0034] Composition 1 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 50 parts by weight (number average molecular weight of about 6000, acrylic equivalent: 3000 bifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO , Kojin) 35 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemicals) 15 parts by weight

The flexibility of the obtained sheet-shaped support was evaluated as follows. The sheet-like support was bent 180 ° in the direction opposite to the side on which the resin coating layer was formed, and the presence or absence of cracks in the resin coating layer was visually evaluated.
The evaluation was made on a three-point scale, with 2 points indicating a slight cracking and 1 point indicating a large cracking. Three and two points are practical, but one point is not practical. The evaluation results are shown in Table 1.

Example 2 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 2 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0037] Composition 2 Ingredient weight urethane resin (trademark: UK-6087, manufactured by Mitsubishi Rayon) 50 parts by weight (number average molecular weight: about 10,000, acrylic equivalent: 5000 bifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO , Kojin) 35 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemicals) 15 parts by weight

Example 3 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 3 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0039] Composition 3 Ingredient weight urethane resin (Trademark: New Frontier R-1204, manufactured by Dai-ichi Kogyo Seiyaku) 50 parts by weight (number average molecular weight of about 3400, acrylic equivalent: 1700 bifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO, manufactured by Kojin) 35 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemicals) 15 parts by weight

Example 4 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 4 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0041] Composition 4 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 65 parts by weight (number average molecular weight of about 6000, acrylic equivalent: bifunctional acrylate oligomer 2000) acryloyl morpholine (Trademark: ACMO 25 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemical Industry) 10 parts by weight

Example 5 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 5 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0043] Composition 5 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 35 parts by weight (number average molecular weight of about 6000, acrylic equivalent: bifunctional acrylate oligomer 2000) acryloyl morpholine (Trademark: ACMO 45 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemistry) 20 parts by weight

Example 6 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 6 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0045] Composition 6 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 50 parts by weight (number average molecular weight of about 6000, acrylic equivalent: 3000 bifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO 35 parts by weight 2-ethylhexyl acrylate 15 parts by weight (trademark: 2-ethylhexyl acrylate, monomer, manufactured by Wako Pure Chemical Industries, Ltd.)

Example 7 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 7 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0047] Composition 7 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 50 parts by weight (number average molecular weight of about 6000, acrylic equivalent: 3000 bifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO 35 parts by weight Alkylphenoxy polyethylene glycol acrylate 15 parts by weight (Trademark: New Frontier NP-2, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)

Example 8 A sheet-shaped support was prepared in the same manner as in Example 1. However, the following composition 8 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0049] Composition 8 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 50 parts by weight (number average molecular weight of about 6000, acrylic equivalent: 3000 bifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO 35 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemistry) 15 parts by weight Rutile titanium dioxide 60 parts by weight (trademark: TAIPAKE CR-58, manufactured by Ishihara Sangyo)

Example 9 A sheet-like support was prepared in the same manner as in Example 1. However, a paper base having a basis weight of 160 g / m ² was used. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

Comparative Example 1 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 9 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0052] Composition 9 Ingredient weight urethane resin (Trademark: BS-550B, manufactured by Arakawa Chemical) 50 parts by weight (number average molecular weight of about 1900, acrylic equivalent: 630 trifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO , Kojin) 35 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemicals) 15 parts by weight

Comparative Example 2 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 10 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0054] Composition 10 Ingredient weight urethane resin (Trademark: New Frontier R-1301, manufactured by Dai-ichi Kogyo Seiyaku Co.) 50 parts by weight (number average molecular weight of about 2100, acrylic equivalent: 700 trifunctional acrylate oligomer) acryloyl morpholine (Trademark: ACMO, manufactured by Kojin) 35 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemicals) 15 parts by weight

Comparative Example 3 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 11 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

[0056] Composition 11 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 50 parts by weight (number average molecular weight of about 6000, acrylic equivalent: 3000 bifunctional acrylate oligomer) isobornyl acrylate 35 weight Part (Trademark: Light acrylate IB-XA, Kyoeisha Yushi) Lauryl acrylate (Trademark: LA, Osaka Organic Chemicals) 15 parts by weight

Comparative Example 4 By the same operation as in Example 1, a sheet-shaped support was prepared. However, the following composition 12 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

The compositions 12 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 50 parts by weight (number average molecular weight of about 6000, acrylic equivalent: 3000 bifunctional acrylate oligomer) Polyethylene glycol diacrylate 35 weight Part (trademark: Light acrylate 9EG-A, manufactured by Kyoeisha Yushi) Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemicals) 15 parts by weight

Comparative Example 5 A sheet-like support was prepared in the same manner as in Example 1. However, the following composition 13 was used as the coating composition for forming the resin coating layer. Table 1 shows the evaluation results obtained in the same manner as in Example 1.

The compositions 13 Ingredient weight urethane resin (Trademark: Beam Set 505B, manufactured by Arakawa Chemical) 10 parts by weight (number average molecular weight of about 6000, acrylic equivalent: bifunctional acrylate oligomer 2000) acryloyl morpholine (Trademark: ACMO 65 parts by weight Lauryl acrylate (trademark: LA, manufactured by Osaka Organic Chemistry) 25 parts by weight

[0061]

[Table 1]

[0062]

The sheet-like support of the present invention is a drawback of the sheet-like support having a surface resin coating layer composed of a cured product of a composition containing as a main component a resin which is cured by electron beam irradiation. It has improved bendability and is extremely useful in practice.

Claims (1)

[Claims] 1. A resin coating layer comprising a sheet-like substrate and a cured product of a composition containing an unsaturated organic compound which is formed on at least one surface of the sheet-like substrate and is curable by electron beam irradiation as a main component. And the unsaturated organic compound contains acryloylmorpholine and a urethane oligomer, and the urethane oligomer has the following characteristics: 1) has an acryloyl group at the end, 2) by gel permeation chromatography (GPC) The measured number average molecular weight is 2000 to 1 in terms of polystyrene.
2000, 3) The acrylic equivalent represented by the following formula (1) is 1000 to
Acrylic equivalent = A / B (1) A: number average molecular weight measured by GPC (polystyrene conversion) B: number of acryloyl groups in one urethane oligomer molecule, sheet-like support body.