JP2012172279A - Release paper for use in manufacture of synthetic leather - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a release paper, which may be easily produced and is jet-black, for use in manufacture of synthetic leather.SOLUTION: A release paper for use in manufacture of synthetic leather, comprises: a paper base layer; an ionizing radiation curable resin layer provided on the paper base layer; and a release layer formed on the ionizing radiation curable resin layer. The ionizing radiation curable resin layer includes, in a dried state thereof, phenol-based particles with an average particle size of 1 to 30 μm in a ratio ranging from 10 to 80 mass%.

Description

  The present invention relates to a release paper for manufacturing synthetic leather, and more particularly to a release paper for manufacturing synthetic leather that is matte and easy to manufacture.

  Conventionally, synthetic leather made of vinyl chloride resin or polyurethane resin as a main raw material has been widely used. Such synthetic leather is often manufactured using release paper. For example, in order to manufacture polyurethane leather, a paste-like polyurethane resin is applied on a release paper, dried and solidified, and then a base fabric is bonded and peeled off from the release paper. If a drawing pattern similar to natural leather or other irregularities are formed on the release paper, a good pattern can be imparted to the surface of the resulting synthetic leather. Based on the same principle, a paste-like polyurethane resin may be applied onto a release paper, dried and solidified, and then a vinyl chloride foam layer may be formed and bonded to the base fabric and peeled off from the release paper. As a method for producing vinyl chloride leather, there is a method in which a vinyl chloride sol is applied on release paper, heated and gelled, a vinyl chloride foam layer is formed, bonded to a base fabric, and peeled off from the release paper. is there.

  As such a release paper, a pigment-coated paper having an oil absorption of 200 to 1000 seconds based on JIS P-3001 is used as a support for a release paper for synthetic leather, and a styrene-butadiene copolymer is used as the pigment-coated paper. A latex having a gel weight fraction with respect to toluene of 80% or more is applied, the release agent layer contains an inorganic pigment having an average particle diameter of 0.5 to 40 μm as a matting agent, and the surface of the release paper There is a release paper for synthetic leather, characterized in that the Oken type smoothness is in the range of 100 to 500 seconds (Patent Document 1). As release paper used for surface formation of matte type synthetic leather, a release layer is formed by adding an inorganic pigment such as silica to the support, which has high gloss and smoothness. The color is pale and jet black is low. However, according to the said structure, it is said that high jetness and uniformity can be provided to synthetic leather.

  In addition, in order to produce a polyurethane-based synthetic leather having a cloth bonded to the back surface, a polyurethane resin is applied to a release paper and dried, and then an isocyanate group is formed on the polyurethane layer to bond the cloth substrate. A polyurethane two-component adhesive composed of a first liquid containing a functional group component and a second liquid composed of a polyol is used. This two-part adhesive has strong adhesive strength and is often used for furniture such as sofas and shoes that are used for a long period of time or those that are used frequently. In the above process, a highly reactive isocyanate group is released. There is a case where it shifts to a pattern paper, the releasability of the process release paper is impaired, and the productivity is lowered. There is an embossed release paper made of paper and an ionizing radiation-cured film as a release paper that can be easily peeled from such a polyurethane two-component adhesive and has excellent heat resistance (Patent Document 2). In Patent Document 2, the cured film does not have an isocyanate compound, a (meth) acryloyl group that has an (meth) acryloyl group and can react with the isocyanate compound, and no (meth) acryloyl group. In addition, a reaction product of a compound capable of reacting with an isocyanate group, which is obtained by curing an ionizing radiation curable composition having a softening point of 40 ° C. or higher with ionizing radiation, is used. In the examples, the ionizing radiation curable composition is coated twice on the paper base material layer provided with the sealing layer to form an ionizing radiation curable film, and is excellent in embossing property, heat resistance, and repetitive peelability. Manufactures embossed release paper.

  There is also an embossed release paper in which an ionizing radiation curable resin layer and a thermosetting silicone layer are laminated in this order and have embossing (Patent Document 3). By using a specific ionizing radiation curable resin layer, a release paper which is excellent in heat resistance, solvent resistance and mechanical strength and can be reused is provided.

JP 2000-328464 A JP 2005-186516 A JP 2009-101685 A

  Synthetic leather has been developed in accordance with customer demands, such as glossy gloss type and matte mat type, and various embossed patterns. For example, when producing black synthetic leather, a deep so-called “jet black” shade may be required. The process peeling for synthetic leather described in Patent Document 1 uses a support having a specific oil absorbency and blends a matting agent having a specific average particle diameter with a release agent in order to impart jetness and uniformity. It is. However, for embossing, shapeability for embossing is essential, but there is no description regarding embossing in the process peeling for synthetic leather described in Patent Document 1.

  On the other hand, when producing release paper whose surface is embossed, it is easy to accurately form the concave portion of the release paper, but the convex portion is accurately formed because the processing pressure tends to be relatively small. For this reason, the contrast (difference between light and dark) of the synthetic leather produced using the release paper may not be sufficient. In particular, as shown in Patent Document 2, when a paper base material layer that has been subjected to a sealing treatment with an acrylic resin containing silica in advance to prevent penetration of the release agent into the paper base material layer is used for the sealing treatment. The embossed contrast may be reduced by the silica or the like.

  On the other hand, the release paper described in Patent Document 3 is obtained by laminating an ionizing radiation curable resin layer and a thermosetting silicone as a release layer on a paper base material layer, and uses a sealing layer containing particles such as silica. The solvent resistance can be ensured without the need. For this reason, it is necessary to use a matte-like paper base layer to make a mat-like release paper, but this release paper is, in order from the side in contact with the synthetic leather, a release layer consisting of a thermosetting silicone layer, Since it consists of an ionizing radiation curable resin layer and a paper base material layer, even if a paper base material layer having a matte feeling is used, it is not sufficient to ensure “jet blackness”.

  Moreover, although patent document 1 mix | blends the matting agent of a specific average particle diameter in a peeling layer and ensures jet blackness, when mixing inorganic particles, such as glass, in the peeling layer of patent document 3 In addition, it is necessary to blend a dispersant, and skill is required for uniform dispersion, so that it is difficult to manufacture at a low cost and in a simple manner.

Under such circumstances, the present invention provides a release paper for producing synthetic leather that has a matte tone, can be embossed, has jetness, and is easy to produce.

  As a result of examining the release paper for synthetic leather production in detail, the present inventors have synthesized phenolic particles having a specific particle size into an ionizing radiation curable resin layer without using a dispersant. Release paper for leather production can be manufactured at low cost and the manufacturing process can be simplified, and the ionizing radiation curable resin layer needs to be irradiated with ionizing radiation such as ultraviolet rays. That the ionizing radiation curable resin layer can be prepared to penetrate the resin, and the blending amount of the phenolic particles is 10 to 80% by mass with respect to 100 parts by mass of the ionizing radiation curable composition. The present invention was completed by finding that jet blackness can be expressed on the surface of the synthetic leather.

  That is, the present invention is for producing synthetic leather comprising a paper base layer, an ionizing radiation curable resin layer provided on the paper base layer, and a release layer formed on the ionizing radiation curable resin layer. It is a release paper, wherein the ionizing radiation curable resin layer contains phenolic particles having an average particle diameter of 1 to 30 μm in a range of 10 to 80% by mass in the dry ionizing radiation curable resin layer. A release paper for producing synthetic leather is provided.

  Further, in the present invention, the ionizing radiation curable resin layer is obtained by curing an ionizing radiation curable composition containing the phenolic particles by ionizing radiation. The release paper for producing synthetic leather according to claim 1 or 2. Is to provide.

The present invention also provides a release paper with embossing, which is the above-mentioned release paper for producing synthetic leather, wherein an emboss is formed on the release layer side.
Furthermore, this invention provides the synthetic leather manufactured using the said release paper for synthetic leather manufacture, or the release paper with an emboss.

  The release paper for manufacturing synthetic leather of the present invention can exhibit jetness by using an ionizing radiation curable resin layer containing phenolic particles. In addition, since the phenolic particles can be uniformly dispersed without using a dispersant, it is possible to simplify the production process of the ionizing radiation-cured resin layer and thus the release paper for producing synthetic leather.

FIG. 1 is a diagram illustrating a release paper for producing synthetic leather according to the present invention, in which a paper base material layer, an ionizing radiation curable resin layer, and a thermosetting silicone layer are laminated. 2 is an enlarged view (720 times) of a release layer of a release paper for producing synthetic leather produced in Example 1. FIG. FIG. 3 is an enlarged view (290 times) of the release layer of the release paper for producing synthetic leather produced in Example 4. FIG. 4 is an enlarged view (720 times) of a release layer of a release paper for producing synthetic leather produced in Example 4. FIG. 5 is an enlarged view (290 times) of the surface of the synthetic leather produced using the release paper for producing synthetic leather produced in Example 4. 6 is an enlarged view (720 times) of the surface of the synthetic leather produced using the release paper for producing synthetic leather produced in Example 4. FIG. FIG. 7 is an enlarged view (720 times) of the release layer of the release paper for synthetic leather production produced in Comparative Example 2. FIG. 8 is an enlarged view (290 times) of the release layer of the release paper for synthetic leather production produced in Comparative Example 4. FIG. 9 is an enlarged view (720 times) of the release layer of the release paper for synthetic leather production produced in Comparative Example 4.

  The first of the present invention is a synthetic leather comprising a paper base material layer, an ionizing radiation curable resin layer provided on the paper base material layer, and a release layer formed on the ionizing radiation curable resin layer. A release paper for production, wherein the ionizing radiation curable resin layer contains phenolic particles having an average particle diameter of 1 to 30 μm in a range of 10 to 80% by mass in the dry ionizing radiation curable resin layer. This is a release paper for manufacturing synthetic leather.

The second of the present invention is the above-mentioned release paper for producing synthetic leather, characterized in that an emboss is formed on the release layer side.
Moreover, the 3rd of this invention is the synthetic leather manufactured using the said release paper for synthetic leather manufacture, or the release paper with an emboss. The present invention will be described in detail with reference to FIG. 1 showing an example of a preferred embodiment of the present invention.

(1) Release paper for manufacturing synthetic leather and release paper with embossing The release paper for manufacturing synthetic leather of the present invention, as shown in FIG. 1, in order from the manufactured synthetic leather side, a thermosetting silicone layer (10), An ionizing radiation curable resin layer (20) and a paper substrate layer (30) are laminated, and the embossed release paper of the present invention is one in which embossing is formed from the thermosetting silicone layer (10) side. is there. An intermediate layer made of a thermoplastic resin may be laminated between the paper base material layer (30) and the ionizing radiation curable resin layer (20). Such an intermediate layer may improve the adhesion between the paper substrate layer (10) and the ionizing radiation curable resin layer (20).

  The ionizing radiation curable resin layer (20) is blended in the dry ionizing radiation curable resin layer with phenolic particles having an average particle diameter of 1 to 30 μm in the range of 10 to 80% by mass in the dry ionizing radiation curable resin layer. The unevenness of the phenolic particles of the ionizing radiation curable resin layer is exposed on the surface of the release layer (10), resulting in a matte tone.

(2) Paper base material layer The paper base material layer used in the release paper for synthetic leather production and the release paper with embossing of the present invention is a step of laminating an ionizing radiation curable resin layer (20) and a thermosetting silicone layer (10). It has the strength to withstand, and has properties such as heat resistance and chemical resistance when a matte tone or uneven pattern is formed on the surface of the synthetic leather applied and formed. In addition to non-coated paper such as kraft paper, high-quality paper, single gloss kraft paper, pure white roll paper, glassine paper, and cup base paper, synthetic paper that does not use natural pulp can also be used. For the processability of synthetic leather, it is preferable to use paper made of natural pulp in terms of durability and heat resistance.

In the present invention, the paper used as the base material layer has a basis weight of 15 to 300 g / m ² , preferably 100 to 180 g / m ² .
In addition, as a paper base material layer used in the present invention, for example, general, clay-coated paper, fine-coated printing paper, coated printing paper, resin-coated paper, processed base paper, release base paper, double-sided coat release base paper, etc. You may use the commercial item in which the sealing layer etc. were formed previously.

(3) Phenolic particles The present invention is characterized in that phenolic particles are blended in the ionizing radiation curable resin layer. The phenolic particles to be blended have an average particle size of 1 to 30 μm, preferably 1 to 20 μm, more preferably 2 to 15 μm, and particularly preferably 5 to 12 μm.

  In the ionizing radiation curable resin layer, the phenolic particles contained in the ionizing radiation curable composition are ionized because the phenolic particles are dispersed in the ionizing radiation curable composition and then cured by irradiation with ionizing radiation such as ultraviolet rays. It is necessary to transmit radiation. The phenolic particles used in the present invention are excellent in ionizing radiation permeability, and can cure the ionizing radiation curable composition to form an ionizing radiation curable resin layer. In addition, inorganic particles such as glass are also present as particles that satisfy the conditions for the permeability to ionizing radiation. However, it is difficult to disperse the glass particles in the ionizing radiation curable composition, and it is necessary to add a dispersant. In addition, skill is required for uniform dispersion, and a special process for kneading the particles into the ionizing radiation curable composition is required. However, the phenolic particles used in the present invention can disperse the particles in the ionizing radiation curable composition without using a dispersant, so that the production process can be simplified and the matte tone table can be used. It turns out that it is extremely excellent in out.

  The average particle diameter of the phenolic particles used in the present invention is preferably 1 to 30 μm as described above. This is because in this range, dispersibility with respect to the ionizing radiation curable composition is excellent, and a jet black matte release paper can be formed. In the present specification, “average particle size” means that phenol particles are observed / photographed with a scanning electron microscope at an arbitrary magnification, and 500 particles are randomly selected from the photograph, and digital calipers are selected. The major axis of each particle is measured and the number average value is taken as the average particle diameter. The shape of the phenolic particles used is not limited to a perfect circle having a sphericity (minor axis / major axis) of 1, but is preferably 0.5 or more, more preferably It is 0.7 or more, particularly preferably 0.9 or more. The sphericity is the average sphericity of phenolic particles.

  Furthermore, the particle size distribution of the phenolic particles is not limited to monodispersion. The variation coefficient of the particle size distribution is preferably 0.65 or less, and more preferably 0.6 or less. It is because it is excellent in the dispersibility in an ionizing radiation-curable composition in this range. The variation coefficient of the particle size distribution is a numerical value obtained by dividing the standard deviation σ of the particle diameter by the average value and expressed as a percentage.

  The phenolic particles used in the present invention are required to have heat resistance to form a matte tone in the synthetic leather by being blended in the ionizing radiation curable resin layer. The melting point of the phenolic particles used in the present invention is 130 or more, more preferably 150 to 300 ° C. In order to ensure such heat resistance, the weight average molecular weight of the phenol-based particles is preferably 5,000 to 20,000, more preferably 7,000 to 15,000. In addition, you may form internal bridge | crosslinking.

As such phenol-based particles, for example, those prepared by the following method can be suitably used.
The phenolic particles used in the present invention can be obtained by addition condensation reaction of phenols and aldehydes.

  The phenols only need to have one or more phenolic hydroxyl groups in the aromatic ring, and may further have a substituent other than the hydroxyl group. For example, cresols such as phenol, o-cresol, m-cresol, p-cresol, mixed cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4- Xylenol, xylenol such as 3,5-xylenol, ethylphenol such as o-ethylphenol, m-ethylphenol and p-ethylphenol, butylphenol such as isopropylphenol, butylphenol and p-tert-butylphenol, p-tert-amylphenol Alkylphenols such as p-octylphenol, p-nonylphenol and p-cumylphenol, halogenated phenols such as fluorophenol, chlorophenol, bromophenol and iodophenol, p-phenylphenol , Monohydric phenol substitutes such as aminophenol, nitrophenol, dinitrophenol, trinitrophenol, hydroxymethylphenol with hydroxy group and methylol group added, hydroxymethylhydroquinone, hydroxymethylresorcin, hydroxymethylxylenol, hydroxymethylpyrogallol, And monovalent phenols such as 1-naphthol and 2-naphthol, polyvalent compounds such as resorcin, alkylresorcin, pyrogallol, catechol, alkylcatechol, hydroquinone, alkylhydroquinone, phloroglucin, bisphenol A, bisphenol F, bisphenol S, dihydroxynaphthalene, etc. Phenols are mentioned. Preferable are phenol, cresol, bisphenol A, and resorcin. These can be used alone or in combination of two or more. One type of phenol may be used, or two or more types may be used in combination.

  The aldehydes are not particularly limited, but for example, formaldehyde, paraformaldehyde, glyoxal, benzaldehyde, acetaldehyde, terephthalaldehyde, hydroxybenzaldehyde, furfural, trioxane, propionaldehyde, polyoxymethylene, chloral, hexamethylenetetramine N-butyraldehyde, caproaldehyde, allyl aldehyde, crotonaldehyde, acrolein, tetraoxymethylene, phenylacetaldehyde, o-tolualdehyde, salicylaldehyde, paraxylene dimethyl ether and the like. Preferable examples include formaldehyde, paraformaldehyde, trioxane, polyoxymethylene, acetaldehyde, paraxylene dimethyl ether and the like. The aldehydes may be used alone or in combination of two or more.

  The charged amount of phenols and aldehydes is theoretically 1: 1, but the blending amount can be appropriately changed in consideration of the catalyst used and the reaction efficiency. When the amount of aldehydes is increased, a compound in which aldehydes are further added to phenols is produced, and therefore internal crosslinking and the like can be formed by the added functional groups.

  In the present invention, an acidic catalyst such as hydrochloric acid, phosphoric acid, sulfuric acid, or the like, or a basic catalyst such as an alkali metal or alkaline earth metal hydroxide or ammonia is used, and an addition condensation reaction is performed. Can be manufactured. If necessary, an emulsifier may be added to carry out emulsion polymerization. The reaction temperature can be appropriately selected according to the amount of raw material charged, and the catalyst used is 10 to 200 ° C. Furthermore, you may mix | blend another component with a reaction liquid. For example, when an alkali metal salt or ammonium salt of carboxymethyl cellulose is blended, phenolic particles having an average particle size of 20 μm or less can be obtained.

  In the present invention, the feed molar ratio of phenols to aldehydes is selected to be 0.9 or less, and an acidic catalyst such as hydrochloric acid, phosphoric acid, sulfuric acid or the like having a concentration of 2.0 mol / L or more in an aqueous medium, And in the presence of a protective colloid agent such as a water-soluble polysaccharide derivative. The reaction solution contains an alkali metal salt or ammonium salt of carboxymethyl cellulose; a colloid agent such as natural glue mainly composed of water-soluble polysaccharide derivatives such as gum arabic, acacia, guar gum, locust bean gum, etc. When added in the range of 0.01 to 5% by weight of the amount of phenol used, the average particle size of the phenolic particles can be 20 μm or less. Examples of the aqueous medium include water or a mixed solvent of water and a water-soluble organic solvent, and an aqueous solvent can be preferably used. In this case, the reaction temperature is 10 to 60 ° C. As the reaction progresses, the reaction solution gradually becomes clouded (suspended), granular phenol resin is formed, and phenolic particles are precipitated. Therefore, the obtained phenolic particles are isolated by filtration, pressing, etc. If it is washed, etc., phenol-based particles having a small residual monomer and an average particle diameter of 20 μm or less can be obtained.

  Further, when an alkylamine compound catalyst containing at least two amino hydrogens and an emulsifier are used as a reaction between phenols and aldehydes, the amount of aldehydes used is 0.1% relative to 1 mol of phenols. The range is 6 to 3.0 mol, preferably 1.1 to 1.8 mol. Examples of the alkylamine compound catalyst containing at least two amino hydrogens include ethylenediamine, diethylenetriamine, triethylenetetraamine, tetraethylenepentamine, pentaethylenehexamine, N- (2-aminoethyl) ethanolamine, N- (2 -Aminoethyl) propanolamine can be used, or a mixture of two or more. When hydroxyethyl cellulose or hydroxyethyl cellulose-2-hydroxypropyltrimethylammonium chloride ether is used as an emulsifier and reacted at a temperature of 100 to 200 ° C., phenolic particles having a particle size of 2 to 20 μm can be obtained.

  Furthermore, as the phenolic particles used in the present invention, a granular phenol resin having a heat melting property and a thermosetting property, which is a reaction product of a phenolic compound and an aldehyde as long as the above conditions are satisfied. In addition, modified phenol resin particles obtained by modifying a phenol resin with another compound or resin on the condition that such a phenol resin is contained in an amount of 80% by mass or more may be used. Examples of such modified phenolic resin particles include rosin-modified phenolic resin described in JP-A No. 2004-149696.

  In the present invention, commercially available products may be used as the phenolic particles. As such phenol-based particles, R100, R200, R800 of “Bellpearl Macro-Sphere Series” manufactured by Air Water Bellpearl Co., Ltd., rosin-modified phenol resin manufactured by Sumitomo Bakelite Co., Ltd., and the like can be used.

(4) Ionizing radiation curable resin layer The ionizing radiation curable resin layer used in the present invention is 10 to 80% by mass, preferably 15 to 70% by mass, more preferably 15 to 70% by mass, with the ionizing radiation curable resin layer (dry). Is blended in the range of 20 to 65% by mass, particularly preferably 30 to 60% by mass. When the ionizing radiation curable composition is blended with phenol-based particles in the above range and cured by thermosetting and ionizing radiation, an ionizing radiation curable resin layer is obtained. When the blending amount of the phenolic particles is less than 10% by mass, the matte tone is weak. On the other hand, when it exceeds 80% by mass, it is not easy to disperse in the ionizing radiation curable composition, and the mechanical strength of the ionizing radiation curable resin layer. The strength may decrease.

  Production of synthetic leather with release paper for synthetic leather production is performed at a temperature of 40 to 150 ° C. When used as release paper with emboss, heat resistance that maintains the embossed shape within the above-mentioned range, and ionizing radiation curing Tack-free properties and dispersibility capable of uniformly dispersing phenolic particles are also required so that the raw material can be easily taken up when the resin layer is formed. In the present invention, as the ionizing radiation curable composition constituting the ionizing radiation curable resin layer, an ionizing radiation curable composition comprising (meth) acryloyl group-containing acrylic copolymer (I), or (meth) acrylic acid ester 35 to 80 parts by mass, 20 to 60 parts by mass of glycidyl (meth) acrylate, and 0 to 30 parts by mass of (meth) acrylic ester to 10 to 30 parts by mass of (meth) acrylic acid An ionizing radiation curable composition comprising a (meth) acryloyl group-containing acrylic copolymer (II) obtained by reaction is cured by ionizing radiation, and the (meth) acryloyl group-containing acrylic copolymer ( I) has a weight average molecular weight (Mw) of 5,000 to 200,000, more preferably 15,000 to 100,000, and particularly preferably 15. It is 000～70,000. The dispersion ratio (Mw / Mn) of the (meth) acryloyl group-containing acrylic copolymer (I) is 1.0 to 5.0, more preferably 1.5 to 4.0, and particularly preferably 1.9. The glass transition temperature (Tg) is 40 to 150 ° C, more preferably 65 to 120 ° C, and particularly preferably 65 to 90 ° C. In addition, in this invention, a weight average molecular weight and a number average molecular weight are the values calculated | required in polystyrene conversion by the gel permeation chromatography (GPC) method.

  As such a (meth) acryloyl group-containing acrylic copolymer (I), for example, a (meth) acrylate monomer unit (A) and an epoxy group-containing (meth) acrylate monomer unit (B) The epoxy group-containing copolymer (C) containing can be obtained by reacting (meth) acrylic acid.

  In the present invention, the (meth) acrylate monomer unit (A) includes methyl methacrylate, methyl acrylate, butyl acrylate, butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, dicyclopentanyl acrylate, Dicyclopentanyl methacrylate, 2- (dicyclopentanyloxy) ethyl acrylate, 2- (dicyclopentanyloxy) ethyl methacrylate, 2- (dicyclopentanyloxy) ethyl-2 ′-(acryloyloxy) ethyl ether 2- (dicyclopentanyloxy) ethyl-2 ′-(methacryloyloxy) ethyl ether, 2- {2- (dicyclopentanyloxy) ethyloxy} -1- {2 ′-(a Liloyloxy) ethyloxy} ethane, 2- {2- (dicyclopentanyloxy) ethyloxy} -1- {2 ′-(methacryloyloxy) ethyloxy} ethane, dicyclopentenyl acrylate, dicyclopentenyl methacrylate, 2- (dicyclo Pentenyloxy) ethyl acrylate, 2- (dicyclopentenyloxy) ethyl methacrylate, 2- (dicyclopentenyloxy) ethyl-2 ′-(acryloyloxy) ethyl ether, 2- (dicyclopentenyloxy) ethyl-2′- (Methacryloyloxy) ethyl ether, 2- {2- (dicyclopentenyloxy) ethyloxy} -1- {2 ′-(acryloyloxy) ethyloxy} ethane, 2- {2- (dicyclopentenyloxy) ethyloxy} -1 -{2 '-(Me Acryloyloxy) ethyloxy} ethane, dimethylol-tricyclodecane diacrylate, dimethylol-tricyclodecane dimethacrylate, isobornyl acrylate, isobornyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate and the like. Among these, methyl methacrylate, methyl acrylate, isobornyl methacrylate, isobornyl acrylate and the like can be preferably used.

  The epoxy group-containing (meth) acrylate monomer unit (B) includes glycidyl methacrylate, methyl glycidyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, 3,4-epoxycyclohexylmethyl acrylate, and aziridinyl (meth) acrylate. and so on.

  The blending ratio of the (meth) acrylate monomer unit (A) to the epoxy group-containing (meth) acrylate monomer unit (B) is determined based on the epoxy group content (meta ) The acrylate monomer unit (B) is blended so as to be 5 to 95% by mass. When less than 5% by mass, a sufficient double bond equivalent cannot be ensured, and the solvent resistance and scratch resistance after curing of the (meth) acryloyl group-containing acrylic copolymer (I) are impaired. There is. On the other hand, if it exceeds 95% by mass, the tackiness of the uncured film due to the Tg being too low may occur, and the moldability may be impaired.

  Moreover, the ionizing radiation curable composition used by this invention is (meth) acrylic acid ester 35-80 mass parts, glycidyl (meth) acrylic acid ester 20-60 mass parts, other (meth) acrylic acid ester 0-. It may be a (meth) acryloyl group-containing acrylic copolymer (II) obtained by reacting 30 parts by mass of a copolymer with 10 to 30 parts by mass of (meth) acrylic acid. (Meth) acrylates and other (meth) acrylates correspond to the above (meth) acrylate monomer units (A), and glycidyl (meth) acrylates are epoxy group-containing (meth) acrylates. It corresponds to the monomer unit (B). Therefore, other (meth) acrylic acid esters can be appropriately selected from the above (meth) acrylate monomer units (A).

  The reaction is obtained by copolymerizing the above monomer units in the presence of a radical initiator. The radical initiator is not particularly limited, but 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 2,2′-azobis (2 -Methylbutyronitrile), 1,1'-azobis- (cyclohexane-1-carbonitrile), azobismethylbutyronitrile, 2,2'-azobis- (4-methoxy-2,4-dimethylvaleronitrile) Azo compounds such as 2,2'-azobisisobutyronitrile, dimethyl 2,2'-azobisisobutyrate; hydrogen peroxide; lauroyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butyl peroxypivalate 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide Xide, succinic acid peroxide, acetyl peroxide, t-butylperoxy-2-ethylhexanoate, m-toluoyl peroxide, benzoyl peroxide, t-butylperoxymaleic acid, t-butylperoxy Laurate, t-butylperoxy-3,5,5-trimethylhexanoate, cyclohexanone peroxide, t-butylperoxyisopropyl carbonate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,2-bis (t-butylperoxy) octane, t-butylperoxyacetate, 2,2-bis (t-butylperoxy) butane, t-butylperoxybenzoate, n-butyl-4,4- Bis (t-butylperoxy) valerate, di Peroxides such as t-butyl-diperoxyisophthalate, methyl ethyl ketone peroxide, dicumyl peroxide, 2,5-dimethyl (t-butylperoxy) hexane, t-butylcumyl peroxide; potassium persulfate, ammonium persulfate A general radical initiator such as a peroxide such as sodium chlorate or a redox initiator based on a combination of these peroxides and a reducing agent may be appropriately selected according to the polymerization method. Although the usage-amount of the said polymerization initiator changes with the kind and superposition | polymerization conditions, it is 0.1-10 mass parts normally with respect to 100 mass parts of said monomers.

  Although superposition | polymerization temperature is based on the kind of polymerization initiator, it is 40-180 degreeC normally, Preferably it is 50-150 degreeC, More preferably, it is 60-130 degreeC. The reaction pressure may be atmospheric pressure or pressurized conditions, and is usually 0.15 to 0.5 MP. The polymerization time is 3 to 15 hours.

  The monomer unit (A) and the monomer unit (B) as described above are polymerized by solution polymerization. Solvents that can be used for solution polymerization include aliphatic hydrocarbon compounds such as n-hexane, heptane, and octane; alicyclic hydrocarbon compounds such as cyclohexane, methylcyclohexane, and ethylcyclohexane; benzene, toluene, xylene, cumene, etc. Aromatic hydrocarbon compounds: Organic solvents such as ether compounds such as tetrahydrofuran, di-n-butyl ether, ethylene glycol dimethyl ether and ethylene glycol diethyl ether, alcohols such as methanol and ethanol, ketones such as acetone and methyl isobutyl ketone, ethylbenzene Well-known solvents such as methyl ethyl ketone and butyl acetate can be used. Of these, methyl ethyl ketone, methanol, toluene, ethylbenzene, butyl acetate and the like are preferably used. Such solvents may be used alone or in combination of two or more.

  The monomer concentration in the reaction solvent is preferably 10 to 80% by mass. When the monomer concentration is less than 10% by weight, a sufficient reaction rate may not be obtained, and when it is higher than 80% by mass, a gelled product may be generated during the reaction.

  In order to obtain a sufficient reaction rate, this reaction is preferably carried out using a catalyst. As the catalyst, phosphines such as triphenylphosphine and tributylphosphine, amines such as triethylamine and dimethylbenzylamine, and sulfides such as dimethylsulfide and diphenylsulfide can be used. Triphenylphosphine is particularly preferable.

  The amount of these catalysts is usually 0.1 to 10% by mass with respect to the epoxy group-containing (meth) acrylate monomer unit (B). When the amount of the catalyst is less than 0.1% by weight based on the epoxy group-containing (meth) acrylate monomer unit (B), a sufficient reaction rate may not be obtained. There is a risk of adversely affecting the physical properties of the produced resin.

  In order to prevent the formation of gelled product during the reaction, hydroquinone, hydroquinone monomethyl ether, phenothiazine, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-acetamino-2,2,6 , 6-tetramethylpiperidine-N-oxyl, 4-benzooxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-oxo-2,2,6,6-tetramethylpiperidine-N-oxyl N-oxy radical compounds such as 2,2,6,6-tetramethylpiperidine-N-oxyl; hydroquinone, hydroquinone monomethyl ether, 2,6-di-t-butyl-4-methylphenol, 2,2 ′ -Methylenebis (4-ethyl-6-tert-butylphenol), 2,6-di-tert-butyl-N, N-dimethyl Tylamino-p-cresol, 2,4-dimethyl-6-t-butylphenol, 4-t-butylcatechol, 4,4'-thio-bis (3-methyl-6-t-butylphenol), 4,4'- Phenolic compounds such as butylidene-bis (3-methyl-6-t-butylphenol); phenothiazine, N, N′-diphenyl-p-phenylenediamine, phenyl-β-naphthylamine, N, N′-di-β-naphthyl Amine compounds such as -p-phenylenediamine and N-phenyl-N'-isopropyl-p-phenylenediamine; 1,4-dihydroxy-2,2,6,6-tetramethylpiperidine, 4-dihydroxy-2,2, Hydroxylamine compounds such as 6,6-tetramethylpiperidine; benzoquinone, 2,5-di-t-butylhydroquinone What quinone compounds; ferrous chloride, copper compounds such as dimethyl copper dithiocarbamate, and the like. These can be used alone or in admixture of two or more. The amount of these polymerization inhibitors is preferably 1 to 10,000 ppm with respect to the entire reaction solution.

  Next, when the obtained copolymer (C) is reacted with (meth) acrylic acid, (meth) acryloyl group-containing acrylic copolymers (I) and (II) can be obtained. A double bond can be introduced into the (meth) acryloyl group-containing acrylic copolymer by modification with (meth) acrylic acid, more preferably acrylic acid. The (meth) acryloyl group-containing acrylic copolymer (I) used in the present invention forms an ionizing radiation cured film. In order to ensure solvent resistance, heat resistance, etc. by curing, the double bond equivalent is 0. It is preferably 0.5 to 4.5 meq / g, more preferably 0.5 to 4.0 meq / g, and particularly preferably 0.7 to 3.6 meq / g. Therefore, (meth) acrylic acid is preferably reacted with the copolymer (C) such that the double bond equivalent is in the above range.

  The reaction between the copolymer (C) and (meth) acrylic acid is carried out in the presence of a tertiary amine catalyst, a quaternary ammonium salt catalyst, a tertiary phosphine catalyst, a quaternary phosphine salt catalyst, and an organotin compound catalyst. Preferably it is done. Specifically, phosphines such as triphenylphosphine and tributylphosphine, amines such as triethylamine and dimethylbenzylamine, and sulfides such as dimethyl sulfide and diphenyl sulfide can be used.

The reaction time and reaction temperature vary depending on the selected solvent, reaction pressure, etc., but the pressure is atmospheric pressure to 0.2 MPa, usually 50 to 160 ° C., and the reaction time is 3 to 50 hours.
The ionizing radiation curable composition of the present invention has a weight average molecular weight (Mw) of 5,000 to 200,000, a dispersion ratio (Mw / Mn) of 1.0 to 5.0, and a glass transition temperature. (Tg) contains 40-150 degreeC (meth) acryloyl group containing acrylic copolymer (I). If the Tg of the (meth) acryloyl group-containing acrylic copolymer (I) is lower than 40 ° C., it will melt at the time of embossing, resulting in poor embossability, or tackiness will occur in the uncured film, and the sheet will be wound. The take may be damaged. On the other hand, when the temperature exceeds 150 ° C., it is necessary to apply an extremely high temperature when embossing is pressed, and flexibility after curing may be impaired. In addition, the measurement of Tg prescribed | regulated to this invention shall be measured by the method as described in the Example mentioned later. Moreover, when it exceeds 150 degreeC, shaping | molding may become difficult. In addition, the copolymer which consists of 35-80 mass parts of (meth) acrylic acid ester, 20-60 mass parts of glycidyl (meth) acrylic acid ester, and 0-30 mass parts of other (meth) acrylic acid ester, (meth) The (meth) acryloyl group-containing acrylic copolymer (II) obtained by reacting 10 to 30 parts by mass of acrylic acid is not limited in weight average molecular weight (Mw) or Tg, but is molded as an embossed release paper. The glass transition temperature is preferably 40 to 150 ° C, more preferably 65 to 120 ° C. Since Tg correlates with the weight average molecular weight (Mw) and the double bond equivalent, the double average should be included and the weight average molecular weight (Mw) should be adjusted so as to satisfy the glass transition temperature. Preferably it is 5,000-200,000, More preferably, it is 15,000-100,000, Most preferably, it is 15,000-70,000. If it is less than 5,000, the solvent resistance and toughness may be inferior. On the other hand, if it exceeds 200,000, the resin viscosity will be high and handling may be difficult. Moreover, glass transition temperature (Tg) is 40-150 degreeC, More preferably, it is 65-120 degreeC, Most preferably, it is 65-90 degreeC. Within this range, after curing the (meth) acryloyl group-containing acrylic copolymer (II), it has excellent solvent resistance and scratch resistance, and there is no tackiness of the uncured film, making it formable. Because it is excellent.

  The ionizing radiation curable composition used in the present invention may be composed only of the (meth) acryloyl group-containing acrylic copolymers (I) and (II). The composition is a mixture of two or more substances. As is clear from the dispersion ratio of the (meth) acryloyl group-containing acrylic copolymer (I), it contains (meth) acryloyl group having different molecular weights. Since an acrylic copolymer is included, the present application also refers to an ionizing radiation curable composition that is composed only of a (meth) acryloyl group-containing acrylic copolymer. On the other hand, you may mix | blend a photoinitiator and others with the ionizing radiation-curable composition used by this invention.

  Examples of the photopolymerization initiator that can be blended in the ionizing radiation curable composition include benzoin ethyl ether, acetophenone, diethoxyacetophenone, benzyldimethyl ketal, 2-hydroxy-2-methylpropiophenone, 2-methyl-1- [4. -(Methylthio) phenyl] -2-morpholinopropane-1, 1-hydroxycyclohexyl phenyl ketone, benzophenone, p-chlorobenzophenone, Michler's ketone, isoamyl N, N-dimethylaminobenzoate, 2-chlorothioxanthone, 2,4-diethyl There is thioxanthone. The compounding quantity of a photoinitiator is 1-10 mass parts with respect to 100 mass parts of (meth) acryloyl group containing acrylic copolymers.

  Furthermore, in order to modify the curing characteristics of the (meth) acryloyl group-containing acrylic copolymer, other resins, silicone compounds, reactive monomers, other photocuring properties are optionally added to the ionizing radiation curable composition. You may contain a polymer etc. in the range which does not injure the characteristic.

  Other resins include methacrylic resin, chlorinated polypropylene, epoxy resin, polyurethane resin, polyester resin, polyvinyl alcohol, polyvinyl acetal, and reactive monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (Meth) acrylate, butyl (meth) acrylate, ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, trimethylolpropane triacrylate, tris (acryloxyethyl) isocyanurate, Examples include pentaerythritol tetraacrylate and dipentaerythritol hexaacrylate.

  As the photocurable polymer, there is a polyfunctional (meth) acrylate oligomer. A compounding quantity is 30 mass parts or less with respect to 100 mass parts of this (meth) acryloyl group containing acrylic copolymer, More preferably, it is 10 mass parts or less. The polyfunctional (meth) acrylate oligomer has two or more (meth) acryloyl groups in one molecule. For example, tricyclodecane dimethylol diacrylate, ethylene oxide-modified diacrylate of bisphenol F, bisphenol A Ethylene oxide modified diacrylate, ethylene oxide modified diacrylate of isocyanuric acid, polypropylene glycol diacrylate, polyethylene glycol diacrylate, trimethylolpropane triacrylate, propylene oxide modified triacrylate of trimethylolpropane, ethylene oxide modified triacrylate of trimethylolpropane , Pentaerythritol triacrylate, pentaerythritol tetraacrylate, ditrimethylolprop Tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, there is such as urethane acrylate. These can also be blended in combination of two or more.

In addition, a commercial item can also be used as an ionizing radiation curable composition. As such a commercially available product, there is a product name “LP-09” manufactured by Toagosei Co., Ltd.
The ionizing radiation curable resin layer used in the present invention is prepared by dispersing the above-described phenolic particles in the ionizing radiation curable composition to prepare a phenolic particle-containing ionizing radiation curable composition, which is used as a paper base material layer. It can be applied, dried and heated, and the solvent is evaporated in a drying furnace to heat cure the phenolic particle-containing ionizing radiation curable composition. In addition, an ionizing radiation curable composition can be hardened | cured by irradiating ionizing radiations, such as an ultraviolet-ray and an electron beam.

  The thickness of the ionizing radiation curable resin layer is preferably 1 to 50 μm, more preferably 3 to 20 μm. If it is thinner than 1 μm, the transfer of fine moldability is worsened, while if it exceeds 50 μm, the curability of the resin may be worsened.

(5) Thermosetting silicone layer In the present invention, a thermosetting silicone layer formed by thermosetting a thermosetting silicone composition comprising an alkenyl group-containing organopolysiloxane, an organohydrogenpolysiloxane and a platinum-based curing catalyst is suitably used. Can be used. In addition, as such a thermosetting silicone composition, you may use a commercial item, for example, the main ingredient of the addition polymerization type silicone material (for example, the mixture of an alkenyl group containing organopolysiloxane and organohydrogenpolysiloxane ( It can be prepared by mixing a curing agent comprising a platinum-based curing catalyst (CAT-PL-50T, manufactured by Shin-Etsu Chemical Co., Ltd., KS-3603) manufactured by Shin-Etsu Chemical Co., Ltd. Moreover, the product name "X-62-9214" by Shin-Etsu Chemical Co., Ltd. can also be used conveniently.

  The thermosetting silicone composition is a material that is in a solid state at room temperature but changes to a liquid state by heating during processing. The thermosetting silicone composition used in the present invention has curability in order to fix a fine uneven pattern formed by embossing and to obtain sufficient film properties such as strength.

  The thermosetting silicone layer can be prepared by applying the thermosetting silicone composition and drying and heating, and the thickness of the thermosetting silicone layer to be formed is preferably in the range of 0.01 to 20 μm.

(6) Method for producing release paper for synthetic leather production The release paper for synthetic leather production of the present invention is a method of applying a phenolic particle-containing ionizing radiation curable composition on a paper base layer, drying the composition, The thermosetting silicone composition is applied onto the ionizing radiation curable composition that has been thermoset, and then heat-dried to form a thermosetting silicone film, and the ionizing radiation treatment is performed from the thermosetting silicone film side. Thus, the above-mentioned thermosetting ionizing radiation composition can be cured and produced.

  A phenolic particle-containing ionizing radiation curable composition can be prepared by diluting an ionizing radiation curable composition, in which a photopolymerization initiator is previously blended, with a solvent, and adding the phenolic particles to this while stirring. .

  When diluting with a solvent, it can be diluted with 10 to 1000 parts by mass, more preferably 100 to 700 parts by mass with respect to 100 parts by mass of the (meth) acryloyl group-containing acrylic copolymer. Within this range, the phenolic particles can be dispersed without settling, and an appropriate viscosity for coating, for example, a viscosity of 10 to 3000 mPa · s at 25 ° C. is given, and in the step of drying it, the silicone compound is appropriate. The transition to a smooth surface.

  Examples of the solvent include aromatic hydrocarbon solvents such as toluene and xylene, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ester solvents such as ethyl acetate, butyl acetate and isobutyl acetate, diethylene glycol ethyl ether acetate, propylene Glycol ether ester solvents such as glycol methyl ether acetate, propylene glycol monomethyl ether, 3-methyl-3-methoxybutyl acetate, ethyl-3-ethoxypropionate, ether solvents such as tetrahydrofuran and dioxane, N-methylpyrrolidone, etc. These aprotic polar solvents are used. The phenolic particles used in the present invention are excellent in affinity for the ionizing radiation curable composition and are dispersed in the composition without settling.

  Phenolic particle-containing ionizing radiation curable compositions are direct gravure coat, reverse gravure coat, gravure offset coat, micro gravure coat, direct roll coat, reverse roll coat, curtain coat, knife coat, air knife coat, bar coat, die coat, It can coat on a paper base material layer by well-known methods, such as spray coating. This is coated on a paper base material layer, dried and heated at a temperature of 90 to 130 ° C., and the solvent is evaporated in a drying furnace to thermally cure the ionizing radiation curable composition. This temperature is a range higher than the softening point of the ionizing radiation curable composition and lower than the temperature at which the ionizing radiation curable composition melts.

Then, a thermosetting silicone is applied onto the thermosetting ionizing radiation curable composition, dried by heating at a temperature of 90 to 130 ° C., and cured in a drying furnace to form a thermosetting silicone film.
Next, ultraviolet rays or electron beams are irradiated from the thermosetting silicone film side to cure the thermosetting ionizing radiation curable composition to form an ionizing radiation curable resin layer. As the ultraviolet light source, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, a xenon lamp, a tungsten lamp, or the like is used. As an electron beam irradiation method, a scanning method, a curtain beam method, a broad beam method, or the like is used, and an acceleration voltage of the electron beam is appropriately 50 to 300 kV.

  In the release paper for producing synthetic leather of the present invention, the ionizing radiation curable resin layer has a thickness of 1 to 50 μm, and the thermosetting silicone layer has a thickness of 0.01 to 20 μm. When phenolic particles are blended in the ionizing radiation curable resin layer, irregularities due to the phenolic particles are exposed on the surface of the release layer, and the release paper for producing synthetic leather can be matte.

  Moreover, when preparing the release paper with an emboss, embossing may be performed before the ionizing radiation curing process, and then the ionizing radiation curing process may be performed. Embossing forms embossing on the thermosetting silicone layer side at a conveying speed of 1 to 20 m / min, plate temperature: 100 to 160 ° C., and linear pressure: 5 to 400 kgf / cm. By heat curing the ionizing radiation curable composition before embossing, the coating properties of the thermosetting silicone composition can be improved, and after the embossing, ionizing radiation curing is performed to ensure the embossing processability. it can. Thereby, the release paper which has a matte tone and embossing can be prepared.

  In addition, in order to prepare the release paper with embossing of this invention, the thickness before embossing is 30-300 micrometers. If the thickness is less than 30 μm, formability may be reduced, and line suitability such as easy cutting during winding in the manufacturing process may be reduced. On the other hand, when it exceeds 300 μm, the width curl of the release paper with emboss becomes large, and the workability may be lowered.

(7) Synthetic leather production method Synthetic leather can be produced in the same manner as in the case of using conventional release paper, using the release paper for producing synthetic leather and the release paper with embossing of the present invention.

  First, the resin composition for synthetic leather is apply | coated on the thermosetting silicone layer of the release paper for synthetic leather manufacture, or the release paper with embossing. The resin layer applied on the thermosetting silicone layer has a matte tone or embossed pattern on the surface of the thermosetting silicone layer. A synthetic leather can be obtained by bonding a base fabric (for example, woven fabric, non-woven fabric, etc.) to this, drying and cooling the resin layer, and then releasing the release paper. Resins such as polyurethane and polyvinyl chloride can be used for the above resin composition for synthetic leather. Examples of the coating method of the resin composition include conventionally known coating methods such as knife coating, roll coating, and gravure coating. In the production of synthetic leather using the release paper for producing synthetic leather and the release paper with embossing of the present invention, the paper base layer and the ionizing radiation curable resin are used even in the case of producing vinyl chloride leather at high temperatures. Peeling between the layers is prevented, and the presence of the ionizing radiation curable resin layer having excellent heat resistance and high mechanical strength and the presence of the thermosetting silicone layer having excellent peelability enable repeated and stable production.

Next, the present invention will be described in more detail by showing specific examples.
Example 1
An ionizing radiation curable composition (manufactured by Toagosei Co., Ltd., trade name “Aron LP-09”) on a paper base material layer (made by Oji Paper Co., Ltd., trade name “OK Process Paper”) having a basis weight of 157 g / m ² , Solid content of 40% by mass) and 100 parts by mass of phenolic particles (product name “Bellpearl R200”, average particle diameter of about 6.8 μm, manufactured by Air Water Velpearl Co., Ltd.) A phenolic particle ultraviolet curable composition solution obtained by adding a solvent and mixing is applied using Meyer bar number: # 14 and dried by heating at 130 ° C. for 30 seconds, and this layer is thermoset. To obtain a thermosetting composition film.

After the thermosetting silicone composition (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “X-62-9214”) is dried on the obtained thermosetting composition film using Meyer bar number: # 8 The coating was applied to 0.4 g / m ^2, and heat-dried at 130 ° C. for 30 seconds to thermally cure the silicone layer. The layer structure of the release paper for manufacturing synthetic leather is OK process paper / R200 + LP-09 / X-62-9214.

Next, using a high-pressure mercury lamp with an output of 120 W / cm, irradiation with ultraviolet rays of 600 mJ / cm ² was performed to cure the thermosetting composition film, thereby obtaining a release paper for producing synthetic leather. FIG. 2 shows an enlarged view (magnification 720 times) of the release layer of the release paper for manufacturing synthetic leather. The phenol particles partially aggregated to form a sea-island structure, but were dispersed without settling. In addition, all the surface enlarged views in this specification are observed using the Keyence Corporation laser microscope VK-9510.

Moreover, after the above-mentioned dry coating film preparation, an embossed plate having a geometric embossed pattern at a conveyance speed of 1 m / min, a plate temperature of 130 ° C., a linear pressure of 161 kgf / cm (manufactured by Dai Nippon Printing Co., Ltd., pattern name: 1213), and then using a high-pressure mercury lamp with an output of 120 W / cm, irradiation with ultraviolet rays of 600 mJ / cm ² was performed to cure the thermosetting composition film to obtain an embossed release paper for synthetic leather production. .

  Furthermore, the compounding amount of R200 was changed to 10 parts by mass, 17 parts by mass, 27 parts by mass, 32 parts by mass, 60 parts by mass, 86 parts by mass and 107 parts by mass, respectively, and embossed for synthetic leather production in the same manner as above. A release paper was prepared.

  About the obtained embossing release paper for synthetic leather manufacture, the gloss value, peelability, and the miscibility of the phenol particles were evaluated by the following methods. In addition, the gloss value was similarly evaluated on the surface of the synthetic leather obtained in the peelability test. The results are shown in Table 2.

(Measuring method)
(I) Gloss value The gloss value (60 ° reflection) was evaluated by a gloss meter IG-320 manufactured by Horiba, Ltd.

(Ii) Peelability For peelability, a non-yellowing carbonate-based polyurethane resin composition having the composition shown in Table 1 was prepared, and the release paper obtained in the experimental example had a dry thickness basis weight of about 36 g / cm ^2. Bar number: coated with # 18, heat-dried at 60 ° C. for 300 seconds, and this layer was thermally cured to obtain a thermosetting composition film. And the polyurethane resin composition same as the above was apply | coated on this thermosetting composition film | membrane as this, the layer was made into the contact bonding layer, the base fabric was affixed, and the base fabric which has a polyurethane skin layer was formed. Thereafter, this was heated and dried at 70 ° C. for 600 seconds, and then the base fabric having a polyurethane skin layer was peeled from the release paper to obtain a synthetic leather. And the surface was observed.
In addition, as for peelability, ○ means that no particle transfer was observed, Δ means that the urethane film was peeled off, but some particle transfer was observed, and × means that the urethane film was not peeled off To do.

(Iii) Miscibility The miscibility of phenolic particles when preparing a phenol-containing particle UV curable composition solution was evaluated. ○ indicates that the particles can be mixed uniformly in the solution without using a dispersant. × indicates that the particles cannot be mixed uniformly without using a dispersant, and most of the particles settled during coating. Show the case.

(Example 2)
Ionizing radiation curable composition (manufactured by Toagosei Co., Ltd., trade name “Aron LP-09”, solid content 40% by mass) with 100 parts by mass of phenol-based particles (produced by Air Water Belpearl Co., Ltd., trade name “Bell Pearl” R800 ", average particle size of about 23 μm), and the blending amounts thereof were changed to 10 parts by mass, 17 parts by mass, 27 parts by mass, 40 parts by mass, 60 parts by mass, and 74 parts by mass, respectively. The embossed release paper for synthetic leather production was obtained in the same manner as described above. The layer structure of the embossed release paper for manufacturing synthetic leather is OK process paper / R800 + LP-09 / X-62-9214.

About this embossing release paper for synthetic leather manufacture, it carried out similarly to Example 1, and evaluated the gloss value, peelability, and miscibility. The results are shown in Table 3.
(Example 3)
Ionizing radiation curable composition (manufactured by Toagosei Co., Ltd., trade name “Aron LP-09”, solid content 40% by mass) with 100 parts by mass of phenol-based particles (produced by Air Water Belpearl Co., Ltd., trade name “Bell Pearl” R100 "and an average particle diameter of about 1.4 μm) were used, except that the blending amounts were changed to 10 parts by mass, 17 parts by mass, 27 parts by mass, 40 parts by mass, 60 parts by mass, and 74 parts by mass, respectively. The embossed release paper for synthetic leather production was obtained in the same manner as in Example 1. The layer structure of the embossed release paper for manufacturing synthetic leather is OK process paper / R100 + LP-09 / X-62-9214.

About this embossing release paper for synthetic leather manufacture, it carried out similarly to Example 1, and evaluated the gloss value, peelability, and miscibility. The results are shown in Table 4.
Example 4
An ionizing radiation curable composition (manufactured by Toagosei Co., Ltd., trade name “Aron LP-09”) on a paper base material layer (made by Oji Paper Co., Ltd., trade name “OK Process Paper”) having a basis weight of 157 g / m ² , Solid content of 40% by mass) and 100 parts by mass of phenolic particles (product name “Bellpearl R200”, average particle diameter of about 6.8 μm, manufactured by Air Water Velpearl Co., Ltd.) A phenol-containing particle UV curable composition solution formed by adding a solvent and mixing is applied using a gravure coater, dried by heating at 90 to 130 ° C., and this layer is thermally cured to obtain a thermosetting composition. A material film was obtained. The dry coating amount of the ionizing radiation curable composition was about 4.5 g / m ² .

  On the obtained thermosetting composition film, a thermosetting silicone composition (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “X-62-9214”) was similarly applied using a gravure coater, and the condition of 90 to 130 ° C. The silicone layer was thermally cured by heating and drying. The layer structure of the release paper for manufacturing synthetic leather is OK process paper / R200 + LP-09 / X-62-9214.

  The release paper for synthetic leather production is embossed with an embossed plate having a geometric embossed pattern (Dai Nippon Printing Co., Ltd., pattern name: 1213), irradiated with ultraviolet light using a high-pressure mercury lamp, and the thermosetting The composition film was cured to obtain an embossed release paper for producing synthetic leather.

  FIG. 3 shows an enlarged view of the release layer at a magnification of 290 times and FIG. 4 shows an enlarged view of the release layer at a magnification of 720 times. An enlarged view of the polyurethane skin layer formed at the time of evaluation of peelability at a magnification of 290 times is shown in FIG. 5, and an enlarged view at a magnification of 720 times is shown in FIG. As shown in FIG. 3, the emboss was clearly formed on the release paper for synthetic leather production, and as shown in FIG. 4, the phenolic resin was uniformly dispersed in the concave and convex portions of the emboss. Also, the embossed pattern is clearly formed on the synthetic leather (polyurethane skin layer) produced as shown in FIG. 5, and as shown in FIG. 6, the release of the phenolic particles from the release paper side for producing synthetic leather Not observed. For this reason, it was found that the phenolic particles are stably present in the ionizing radiation curable resin layer.

  Further, the embossed plate was subjected to measurement of the embossing depth and the transfer rate to the release paper, and the average values are shown in Table 7. The embossed plate had a grain depth of about 43.7 μm. In addition, various grain depths in this specification were measured using a laser microscope VK-9510 manufactured by Keyence Corporation.

(Comparative Example 1)
Ionizing radiation curable composition (Toagosei Co., Ltd., trade name “Aron LP-09”, solid content 40% by mass) 100 parts by mass of silica-coated melamine particles (Nissan Chemical Industry Co., Ltd., trade name “Opto”) Beads 500S ”and average particle diameter of about 0.5 μm), and the blending amounts were changed to 4 parts by mass, 10 parts by mass, 17 parts by mass, 27 parts by mass, 40 parts by mass, 60 parts by mass, and 74 parts by mass, respectively. Except that, emboss release paper for synthetic leather production was obtained in the same manner as in Example 1. The layer structure of the embossed release paper for manufacturing synthetic leather is OK process paper / 500S + LP-09 / X-62-9214.

About this embossing release paper for synthetic leather manufacture, it carried out similarly to Example 1, and evaluated the gloss value, peelability, and miscibility. The results are shown in Table 5. As shown in Table 5, since most of the particles settle, the coating amount hardly changes in the blending range of 40 to 74 parts by mass. This is a significant difference compared to Example 3 which has an average particle diameter of the same level, and has a relatively small specific gravity (true specific gravity of 1.) as compared with pure glass particles having a specific gravity of about 2.5. 5 g / cm ³ ) Even silica-coated melamine particles have low miscibility. Therefore, it can be seen that the silica particles have strong cohesive force and low miscibility in the organic solution.

(Comparative Example 2)
An ionizing radiation curable composition (manufactured by Toagosei Co., Ltd., trade name “Aron LP-09”) on a paper base material layer (made by Oji Paper Co., Ltd., trade name “OK Process Paper”) having a basis weight of 157 g / m ² In addition, an ultraviolet curable composition solution obtained by adding a solvent and mixing so that the total amount becomes 160 parts by mass is added to 100 parts by mass using a gravure coater, and the condition is 90 to 130 ° C. The layer was heat-dried and the layer was heat-cured to obtain a thermosetting composition film. The dry coating amount of the ionizing radiation curable composition was about 4.5 g / m ² .

  On the obtained thermosetting composition film, a thermosetting silicone composition (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “X-62-9214”) was applied using the same gravure coater as in Example 4. The silicone layer was heat-dried under the conditions of 90 to 130 ° C., and a release paper for producing synthetic leather was produced. The layer structure of the release paper for manufacturing synthetic leather is OK process paper / LP-09 / X-62-9214.

  Subsequently, the release paper for manufacturing synthetic leather is embossed with an embossed plate having a geometric embossed pattern (Dai Nippon Printing Co., Ltd., pattern name: 1213), irradiated with ultraviolet light using a high-pressure mercury lamp, The thermosetting composition film was cured to obtain an embossed release paper for producing synthetic leather.

For the obtained release paper, the gloss value, peelability and miscibility were evaluated in the same manner as in Example 1. The results are shown in Table 6.
In this case, the transfer rate to the release paper was also measured, and the average value is shown in Table 7. It turns out that Example 4 shows the transfer rate comparable as compared with the comparative example 2 which does not contain a phenol particle. Therefore, it can be seen that the difference in the gloss value between Example 4 and Comparative Example 2 is due to the surface irregularities finer than the texture caused by the phenol particles.

Moreover, the enlarged view (720 times) of a peeling layer is shown in FIG. An embossed pattern was formed, but the surface was smooth because no particles were blended.
(Comparative Example 3)
An ionizing radiation curable composition (manufactured by Toagosei Co., Ltd., trade name “Aron LP-09”) on a paper base material layer (made by Oji Paper Co., Ltd., trade name “OK Process Paper”) having a basis weight of 157 g / m ² , Solid content 40% by mass) 100 parts by mass and silicone powder (trade name “KMP-600”, manufactured by Shin-Etsu Chemical Co., Ltd., average particle diameter of about 5 μm) 32 parts by mass with a total amount of 192 parts by mass The silicone-containing powder UV curable composition solution obtained by adding and mixing is applied with a Meyer bar number: # 14 so that the coating thickness is about 8.8 g / m ² after drying, and is 30 at 130 ° C. The layer was heat-dried for 2 seconds, and this layer was thermally cured to obtain a thermosetting composition film.

On the obtained thermosetting composition film, a thermosetting silicone composition (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “X-62-9214”) was applied using Meyer bar number: # 8, and the coating thickness There was applied to approximately 0.4 g / m ² after drying, also heat-dried under conditions of 30 seconds at 130 ° C., and the silicone layer is thermally cured. The layer structure of the release paper for manufacturing synthetic leather is OK process paper / KMP-600 + LP-09 / X-62-9214.

Next, using a high-pressure mercury lamp with an output of 120 W / cm, irradiation with ultraviolet rays of 600 mJ / cm ² was performed to cure the thermosetting composition film, thereby obtaining a release paper for producing synthetic leather.
For the obtained release paper, the gloss value, peelability and miscibility were evaluated in the same manner as in Example 1. The results are shown in Table 6.

It was found that when silicone powder was blended, the silicone powder transferred to the entire surface of the synthetic leather.
(Comparative Example 4)
Glass-containing particles obtained by adding a solvent to 100 parts by mass of glass resin-containing UV resin having an average particle size of about 6 μm (manufactured by DIC Graphics, trade name “FM-80”) so that the total amount becomes 160 parts by mass. An ultraviolet curable composition solution was prepared.

A thermoplastic resin (trade name “TPX”, manufactured by Mitsui Chemicals, Inc.) having a thickness of 37 μm is formed on a paper base layer (made by Hokuetsu Kishu Paper Co., Ltd., trade name “H230” paper) having a basis weight of 125 g / m ^2. The above glass-containing particle ultraviolet curable composition solution is coated on the surface using a gravure coater, dried by heating at 90 to 130 ° C., and this layer is thermally cured and thermally cured. A composition film was obtained. The dry coating amount of the ionizing radiation curable composition was about 5.0 g / m ² .

  On the obtained thermosetting composition film, a thermosetting silicone composition (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “X-62-9214”) was applied using the same gravure coater as in Example 5. Heat-dried under the conditions of 90 to 130 ° C., the silicone layer was thermally cured, and a release paper for synthetic leather was produced. The layer structure of the release paper for producing synthetic leather is HR paper / TPX / FM-80 / X-62-9214.

  Subsequently, the release paper for manufacturing synthetic leather is embossed with an embossed plate having a geometric embossed pattern (Dai Nippon Printing Co., Ltd., pattern name: 1213), irradiated with ultraviolet light using a high-pressure mercury lamp, The thermosetting composition film was cured to obtain an embossed release paper for producing synthetic leather.

About the obtained embossing release paper for synthetic leather manufacture, the gloss value, peelability, and miscibility were evaluated in the same manner as in Example 1. The results are shown in Table 6.
FIG. 8 shows an enlarged view of the release layer at a magnification of 290 times and FIG. 9 shows an enlarged view of the release layer at a magnification of 720 times. Although the matte tone by the unevenness | corrugation was formed on the surface of the peeling layer by the glass particle, the crack generate | occur | produced by embossing and the glass particle which protrudes from the surface of a peeling layer was observed. Further, the glass particle-containing UV resin “FM-80” deteriorated with time after being cured by ionizing radiation.

(Comparative Example 5)
45 parts by mass of glass particles having an average particle diameter of about 6 μm are blended with 100 parts by mass of the same type of UV resin as in Example 1 (trade name “Aron LP-07” manufactured by Toa Gosei Co., Ltd., solid content: 45% by mass). After that, a solvent was added and mixed so that the total amount was 200 parts by mass to prepare a glass-containing particle ultraviolet curable composition solution. However, the glass particles settle in the glass-containing particle UV curable composition solution, and the glass-containing particle UV curable composition solution cannot be coated on the paper base layer. An embossed release paper for leather production could not be produced. The results are shown in Table 6.

  The release paper for producing synthetic leather of the present invention is useful because it can produce mat-like synthetic leather at low cost.

10 ... thermosetting silicone layer,
20 ... ionizing radiation curable resin layer,
30 ... Paper base material layer

Claims (4)

A release paper for producing synthetic leather comprising a paper base layer, an ionizing radiation curable resin layer provided on the paper base layer, and a release layer formed on the ionizing radiation curable resin layer. ,
The ionizing radiation curable resin layer contains phenolic particles having an average particle diameter of 1 to 30 μm in a dry ionizing radiation curable resin layer in a range of 10 to 80% by mass, and is a release paper for producing synthetic leather. . The ionizing radiation curable resin layer is
The release paper for synthetic leather manufacture according to claim 1, wherein the ionizing radiation curable composition containing the phenolic particles is cured by ionizing radiation.   The release paper for manufacturing synthetic leather according to claim 1 or 2, wherein an emboss is formed on the release layer side.   The synthetic leather manufactured using the release paper for synthetic leather manufacture of Claim 1 or 2, or the release paper with an embossing of Claim 3.