阅读说明：本技术 离型纸，使用该离型纸的胶粘片、标签用原纸以及标签 (Release paper, adhesive sheet using the same, base paper for label, and label ) 是由 高山久幸 于 2019-11-11 设计创作，主要内容包括：本发明的目的在于提供一种离型纸,使用该离型纸的胶粘片、标签用原纸以及标签；其中,该离型纸即使在填充层中含有生物质来源的树脂和/或生物降解性树脂,也具有与化石燃料来源的聚烯烃层同等的离型性,且不逊于以往种类的离型纸。本发明提供的离型纸(10)具备：纸基材(11)；以及填充层(12),其在所述纸基材(11)的一面或两面上,并含有生物质来源的树脂和/或生物降解性树脂；以及在所述填充层(12)的至少一个上的离型剂层(13)。(The invention aims to provide release paper, an adhesive sheet using the release paper, base paper for a label and the label; the release paper has a release property equivalent to that of a polyolefin layer derived from fossil fuel even when a filler layer contains a biomass-derived resin and/or a biodegradable resin, and is not inferior to conventional types of release paper. The release paper (10) provided by the invention comprises: a paper base (11); and a filler layer (12) which is provided on one or both surfaces of the paper base (11) and contains a biomass-derived resin and/or a biodegradable resin; and a release agent layer (13) on at least one of the filling layers (12).)

1. A release paper characterized by comprising:

a paper substrate; and

a filler layer which is provided on one or both surfaces of the paper base and contains a biomass-derived and/or biodegradable resin; and

a release layer on at least one of the fill layers.

2. The release paper according to claim 1,

wherein the biomass-derived resin contains a biomass polyolefin produced by polymerizing a biomass-derived monomer.

3. The release paper according to claim 2,

wherein the biomass-derived monomer is biomass-derived ethylene.

4. The release paper according to claim 2,

wherein the biomass polyolefin has 0.910g/cm³Above and less than 0.965g/cm³The density of (c).

5. Release paper according to any one of claims 1 to 4,

wherein the biomass-derived resin contained in the packed layer is 1 wt% or more based on the whole packed layer.

6. The release paper according to claim 1,

wherein the biodegradable resin is selected from the group consisting of aliphatic polyesters and derivatives thereof.

7. The release paper according to claim 1,

wherein the biodegradable resin contained in the filler layer is 50 wt% or more of the entire filler layer.

8. Release paper according to any one of claims 1 to 7,

wherein the filler layer further comprises a fossil fuel-derived polyolefin.

9. Release paper according to any one of claims 2 to 5,

wherein the main resin forming the filling layer is polyethylene.

10. Release paper according to any one of claims 1 to 9,

wherein the release agent layer contains an organic silicon release agent.

11. The release paper according to claim 10,

wherein the organic silicon type release agent is an emulsion type or solvent-free type organic silicon type release agent.

12. An adhesive sheet characterized in that,

comprising the release paper according to any one of claims 1 to 11, an adhesive layer and a substrate for an adhesive sheet.

13. The adhesive sheet according to claim 12,

wherein the adhesive layer contains a biomass adhesive.

14. The adhesive sheet according to claim 13,

the biomass adhesive contains a tackifier, the tackifier contains more than one selected from rosin resin and terpene resin, and the biomass degree of the adhesive layer is more than 1.0%.

15. The adhesive sheet according to any one of claims 12 to 14,

wherein the base material for the adhesive sheet is paper or a biomass resin film.

16. A base paper for labels, characterized in that,

comprising the release paper according to any one of claims 1 to 11, an adhesive layer and a substrate for label.

17. The base paper for labels as claimed in claim 16,

wherein the adhesive layer contains a biomass adhesive.

18. The base paper for labels as claimed in claim 17,

the biomass adhesive contains a tackifier, the tackifier contains more than one selected from rosin resin and terpene resin, and the biomass degree of the adhesive layer is more than 1.0%.

19. The base paper for labels as claimed in any one of claims 16 to 18,

wherein the base material for label is paper or biomass resin film.

20. A label, characterized in that it comprises, in a first aspect,

the base paper for labels as claimed in any one of claims 16 to 19.

Technical Field

The present invention relates to a release paper, an adhesive sheet using the release paper, a base paper for a label, and a label.

Background

In recent years, in order to reduce environmental load, it has been studied to replace a part of the fossil fuel-derived raw materials with biomass-derived raw materials and biodegradable resins, which are renewable organic resources produced in animals and plants, in the resin raw materials.

However, in a release paper having a release agent layer on the surface of a paper substrate, in order to suppress the penetration of the release agent into the paper substrate as much as possible and to maximize the release property, a polyolefin layer is generally formed as a filler layer between the paper substrate and the release agent layer (see patent document 1). The purpose of the filling layer is to prevent the release agent from invading the paper substrate during the coating process and to form a uniform release agent layer on the surface. For the above reasons, it is also desirable that the polyolefin forming the polyolefin layer also contains a resin using biomass and a biodegradable resin.

Prior Art

Patent document

Patent document 1: japanese patent laid-open publication No. Hei 02-191796

Disclosure of Invention

Technical problem to be solved by the invention

As the biomass-derived resin, various resins that have been studied and developed such as: polylactic acid, cellulose resin, polypropylene terephthalate using 1, 3-propanediol derived from biomass, biomass polyester using ethylene glycol derived from biomass, biomass polyamide using fatty acid derived from biomass such as nylon 11 and nylon 4, biomass polyurethane using diol derived from biomass, biomass polyethylene using ethylene derived from biomass, biomass polyolefin such as biomass polypropylene using propylene derived from biomass, and the like.

However, although it is desired to develop a release paper that reduces environmental load, a biomass-derived resin and a biodegradable resin have not been used for a filler layer in the release paper from the viewpoint of manufacturing cost and popularity.

Accordingly, an object of the present invention is to provide a release paper, an adhesive sheet using the release paper, a base paper for labels, and a label; the release paper has a release property equivalent to that of a polyolefin layer derived from fossil fuel even when a filler layer contains a biomass-derived resin and/or a biodegradable resin, and is not inferior to conventional types of release paper.

Means for solving the problems

In view of the above problems, the inventors of the present invention have conducted intensive studies. As a result, they have found that a filler layer containing a biomass-derived resin and/or a biodegradable resin has a release property equivalent to that of a polyolefin layer containing a fossil fuel-derived resin and is not inferior to conventional types of release paper, and an adhesive sheet, a base paper for labels, and a label using the release paper. Specifically, the present invention provides the following.

(1) Embodiment 1 of the present invention is a release paper characterized by comprising: a paper substrate; and a filler layer which is provided on one or both surfaces of the paper base and contains a biomass-derived and/or biodegradable resin; and a release agent layer on at least one of the filling layers.

(2) Embodiment 2 of the present invention is the release paper described in the above (1), wherein the biomass-derived resin contains a biomass polyolefin produced by polymerizing a biomass-derived monomer.

(3) Embodiment 3 of the present invention is the release paper according to the above (2), wherein the monomer derived from biomass is ethylene derived from biomass.

(4) Embodiment 4 of the present invention is the release paper according to the above (2), wherein the biomass polyolefin has a density of 0.910g/cm³Above and less than 0.965g/cm³The density of (c).

(5) Embodiment 5 of the present invention is the release paper according to any one of the above-described embodiments (1) to (4), wherein the biomass-derived resin contained in the filler layer is 1 wt% or more based on the entire filler layer.

(6) Embodiment 6 of the present invention is the release paper according to the above (1), wherein the biodegradable resin is selected from the group consisting of aliphatic polyesters and derivatives thereof.

(7) Embodiment 7 of the present invention is the release paper according to the above (1), wherein the biodegradable resin contained in the filler layer is 50 wt% or more based on the entire filler layer.

(8) Embodiment 8 of the present invention is the release paper according to any one of the above-described embodiments (1) to (7), wherein the filler layer further contains a polyolefin derived from fossil fuel.

(9) Embodiment 9 of the present invention is the release paper according to any one of the above-described embodiments (2) to (5), wherein a main resin forming the filling layer is polyethylene.

(10) The release paper according to embodiment 10 of the present invention is the release paper according to any one of the above (1) to (9), wherein the release agent layer contains a silicone-based release agent.

(11) Embodiment 11 of the present invention is the release paper described in (10) above, wherein the silicone release agent is an emulsion type or solvent-free silicone release agent.

(12) A 12 th embodiment of the present invention is an adhesive sheet comprising the release paper according to any one of the above-described embodiments (1) to (11), an adhesive layer, and a base material for an adhesive sheet.

(13) Embodiment 13 of the present invention is the adhesive sheet according to (12) above, wherein the adhesive layer contains a biomass adhesive.

(14) Embodiment 14 of the present invention is the adhesive sheet as described in (13) above, wherein the biomass adhesive contains a tackifier, the tackifier contains one or more selected from rosin resins and terpene resins, and the biomass content of the adhesive layer is 1.0% or more.

(15) Embodiment 15 of the present invention is the adhesive sheet according to any one of the above-described embodiments (12) to (14), wherein the base material for the adhesive sheet is paper or a biomass resin film.

(16) A 16 th embodiment of the present invention is a base paper for labels, which is characterized by comprising the release paper, the adhesive layer, and the base material for labels according to any one of the above-described embodiments (1) to (11).

(17) Embodiment 17 of the present invention is the base paper for label as described in (16) above, wherein the adhesive layer contains a biomass adhesive.

(18) Embodiment 18 of the present invention is the base paper for labels as described in (17) above, wherein the biomass adhesive contains a tackifier, the tackifier contains one or more selected from rosin resins and terpene resins, and the biomass content of the adhesive layer is 1.0% or more.

(19) A 19 th embodiment of the present invention is the base paper for label according to any one of the above (16) to (18), wherein the base material for label is paper or a biomass resin film.

(20) Embodiment 20 of the present invention is a label using the base paper for label according to any one of the above-mentioned embodiments (16) to (19).

Effects of the invention

According to the present invention, there can be provided a release paper, an adhesive sheet using the release paper, a base paper for a label, and a label; the release paper has a release property equivalent to that of a polyolefin layer derived from fossil fuel even when a filler layer contains a biomass-derived resin and/or a biodegradable resin, and is not inferior to conventional types of release paper.

Drawings

Fig. 1 is a schematic cross-sectional view showing one embodiment of a release paper according to the present invention.

Fig. 2 is a schematic cross-sectional view showing another embodiment of the release paper according to the present invention.

Fig. 3 is a schematic cross-sectional view showing an example of a base paper for labels using the release paper according to the present invention.

Detailed Description

The embodiments of the present invention will be described in detail below.

(Release paper)

Fig. 1 is a schematic cross-sectional view showing one embodiment of a release paper 10 according to the present invention. The release paper 10 includes a paper base material 11; and a filler layer 12 which is provided on one or both surfaces of the paper base 11 and contains a biomass-derived resin and/or a biodegradable resin; and a release agent layer 13 on at least one of the filling layers 12. The release paper 10 may be a double-sided release paper (not shown) in which the filler layer 12 and the release agent layer 13 are provided on both sides of the paper base material 11. In the release paper 10 according to the present embodiment, a curl suppression layer may be provided on a surface of the paper base 11 opposite to the surface on which the filler layer 12 and the release agent layer 13 are provided. The curl suppressing layer is not particularly limited, and may be, for example, the filler layer 12 or a later-described polyolefin layer 14 derived from fossil fuel.

(paper substrate)

The paper substrate 11 used in the release paper 10 according to the present embodiment is not particularly limited, and examples thereof include: glassine paper, half glassine paper, high-quality paper, kraft paper, clay-coated paper, medium paper, alkaline paper, coated paper, board paper, white board paper, so-called dust-free paper which generates less dust as disclosed in japanese patent laid-open No. h 6-11959, and the like. In order to improve the adhesion to the filler layer 12, the paper base 11 may be subjected to various surface treatments such as heating and corona discharge treatment.

The paper base 11 preferably has a thickness of 40 μm or more and 300 μm or less. If the thickness of the paper base 11 is less than 40 μm, wrinkles are increased when the release paper 10, the label base paper 20, or the adhesive sheet is manufactured, or the suitability for press working in label processing is poor when the label base paper 20 is manufactured. On the other hand, when the thickness of the paper base 11 exceeds 300 μm, the rigidity becomes too high, and the handling performance is lowered. Further, the thickness of the paper base 11 is measured in accordance with JIS P8118: 2014 to perform the measurement.

The basis weight of the paper substrate 11 is preferably 40g/m²Above, and 200g/m²Hereinafter, more preferably 50g/m²Above, and 160g/m²The following. When the basis weight of the paper substrate 11 is less than 40g/m²When it is used, the paper strength may be weakened and the processability may be poor. On the other hand, when the basis weight of the paper base material 11 exceeds 200g/m²In the case of this, the operability may be poor.

(filling layer)

The filler layer 12 according to the present embodiment contains a biomass-derived resin and/or a biodegradable resin, and may further contain a fossil fuel-derived polyolefin. In the present invention, when the packed layer 12 contains the biomass-derived resin, the amount of the fossil fuel-derived polyolefin can be reduced as compared with the conventional packed layer, so that the environmental load can be reduced. When the filler layer 12 contains a biodegradable resin, a part of the release paper 10 is biodegradable, and thus the environmental load can be reduced.

The biomass-derived resin refers to a resin produced from biomass as a raw material. In addition, the resin derived from biomass may have a biodegradable function. In the present invention, a biomass resin having a biodegradation function is defined as a biomass resin. In this case, the packed layer 12 may contain two or more types of resins derived from biomass having different biomass degrees. Examples of the biomass-derived monomer used for producing the biomass-derived resin include: biomass-derived olefins such as biomass-derived ethylene and biomass-derived propylene are particularly preferred. These biomass-derived monomers may be used alone or in combination of two or more.

In the present invention, the biomass-derived resin preferably contains a biomass polyolefin obtained by polymerizing a biomass-derived monomer, and the biomass polyolefin is preferably a biomass-derived polyethylene obtained by polymerizing a biomass-derived ethylene. In the present invention, the terms "biomass-derived resin" and "biomass polyolefin" mean that a biomass-derived raw material is used as at least a part of the raw material, and do not mean that all the raw material is derived from biomass.

The biomass-derived ethylene can be produced from, for example, the following biomass-derived raw materials. First, bioethanol is produced from biomass. Examples of biomass as a raw material for producing bioethanol include: sugarcane, corn, sugar beet, cassava, sugar beet, wood, algae, and the like. Among these biomasses, from the viewpoint of production efficiency, sugar cane, corn and sugar beet which contain a large amount of sugars or starch are preferable.

Then, biomass ethanol as a starting material is converted into ethylene by a dehydration reaction, the obtained biomass-derived ethylene is separated from the produced water and the like, and the separated biomass-derived ethylene may be purified by an adsorption method or the like. The purified biomass-derived ethylene can be used as a raw material for polyethylene by employing conventionally known chemical engineering techniques.

The biomass-derived polyethylene is not particularly limited, and examples thereof include: high Density Polyethylene (HDPE), Medium Density Polyethylene (MDPE), Low Density Polyethylene (LDPE), and Linear Low Density Polyethylene (LLDPE), and the like. Among them, the polyethylene derived from biomass is preferably Linear Low Density Polyethylene (LLDPE) from the viewpoints of popularization, availability, and the like.

The biomass-derived propylene can be produced by a metathesis reaction using the biomass-derived ethylene as a starting material. Further, as another production method, 1, 3-propanediol can be produced by changing fermentation conditions for the above-mentioned biomass-derived raw material, and propylene derived from biomass can be produced by subjecting it to dehydration reaction.

The content of the biomass-derived resin produced by polymerization of the biomass-derived monomer contained in the packed layer 12 is preferably 1 wt% or more, more preferably 5 wt% or more, and still more preferably 8 wt% or more, relative to the entire packed layer 12. When the content of the biomass-derived resin in the packed layer 12 is 1 wt% or more, the amount of fossil fuel used can be reduced as compared with the conventional case. Furthermore, the packed layer 12 need not contain 100 wt% of the biomass-derived resin. The filler layer 12 may contain a polyolefin derived from fossil fuel in addition to the biodegradable resin and/or the resin derived from biomass. On the other hand, in the case of using the biomass polyolefin in the filling layer 12, as the compounding ratio of the biomass-derived resin becomes higher, the viscosity value of the surface of the filling layer 12 tends to increase, and workability such as windability may decrease when the filling layer 12 is laminated on the paper base 11. Therefore, when using a biomass polyolefin, the filler layer 12 preferably contains a fossil fuel-derived polyolefin in addition to the biodegradable resin and/or the biomass-derived resin, and preferably contains the biomass-derived resin in an amount of 100 wt% or less, more preferably 50 wt% or less, and still more preferably 30 wt% or less, based on the entire filler layer 12.

In biomass polyolefin, theoretically, if olefins such as ethylene derived from biomass are used as a raw material of polyolefin, the concentration of carbon derived from biomass is 100%, and therefore the biomass degree of biomass polyolefin is 100%. In addition, since the concentration of carbon derived from biomass in the fossil fuel-derived polyolefin produced using only a fossil fuel-derived raw material is 0%, the biomass content of the fossil fuel-derived polyolefin is 0%. In the packed layer 12, at least a part of the raw material used is a biomass-derived raw material, and the biomass content does not necessarily have to be 100%. The biomass content in the packed layer 12 is preferably 1% or more, more preferably 3% or more, and still more preferably 5% or more. When the biomass degree in the packed layer 12 is 1% or more, the environmental load can be reduced as compared with the conventional case.

Here, the biomass degree is an index indicating a mixing ratio of a fossil fuel-derived raw material and a biomass-derived raw material, is determined by measuring the concentration of radioactive carbon (C14), and is represented by the following formula.

Biomass (%) ═ C14 concentration (pMC) × 0.935.

The C14 is contained in a constant concentration in the biomass, but is scarcely present in fossil fuels. Therefore, the concentration of C14 was measured by accelerator mass spectrometry and used as an index of biomass content ratio.

The method for polymerizing biomass polyolefin according to the present embodiment is not particularly limited, and can be carried out by a conventionally known method. The polymerization temperature and the polymerization pressure are preferably adjusted as appropriate depending on the polymerization method and the polymerization apparatus. The polymerization apparatus is not particularly limited, and conventionally known apparatuses can be used.

The biomass polyolefin preferably has 0.910g/cm³Above and less than 0.965g/cm³The density of (c). When the density is less than 0.910g/cm³In this case, the heat resistance tends to be low. On the other hand, when the density is 0.965g/cm³In the above case, the release force becomes large. The density of the biomass polyolefin can be measured according to the method specified in method A in JIS K7112-1980 after annealing described in JIS K6760-1995.

The biodegradable resin is not particularly limited as long as it has biodegradability and good film-forming properties and satisfies mechanical properties, durability, and the like as the release paper 10 when the filler layer 12 is formed, and may be a material of biological origin or a material of petroleum origin. Examples of such biodegradable resins include: aliphatic polyesters and derivatives thereof, polyesters produced by microorganisms, aromatic-aliphatic polyesters, aliphatic polyester carbonates, aliphatic polyester amides, aliphatic polyester ethers, polyamino acids, polyvinyl alcohols, starches, cellulose and cellulose derivatives such as cellulose acetate, hydroxyethyl cellulose and hydroxypropyl cellulose, polysaccharides such as chitin, chitosan and mannan, and the like, and among these, aliphatic polyesters and derivatives thereof are preferably used.

Examples of the aliphatic polyester and its derivative include: polylactic acid (PLA), polybutylene succinate-based resins, polyesters containing 3-hydroxyalkanoic acid as a monomer unit, and the like.

The polylactic acid (PLA) is produced from lactic acid obtained by fermentation of plants such as corn, and is a biological cycle type because it is produced from lactic acid produced by microbial decomposition into water and carbon dioxide, which again has a linkage to assist plant growth, and is preferably used in the present invention.

Specific examples of the above-mentioned polybutylene succinate-based resin include polybutylene succinate (PBS), a polybutylene succinate-co-adipate (PBSA), polybutylene succinate-lactide, and the like. Products (commercially available products) usable as the polybutylene succinate-based resin include polybutylene succinate-based resin "BioPBS" (registered trademark) produced by Mitsubishi chemical corporation (polybutylene succinate, polybutylene succinate-butylene adipate copolymer, etc.), polybutylene succinate-based resin "Bionon" (registered trademark) produced by Showa electric corporation, polybutylene succinate-based resin produced by Shandong Fuwin New Material corporation, polybutylene adipate terephthalate resin "Eco Flex" (registered trademark) produced by Pasteur corporation, and the like. The polybutylene succinate resin may be a material derived from a living organism or a material derived from petroleum.

As specific examples of the polyester containing a 3-hydroxyalkanoic acid as the monomer unit, there may be mentioned: PHB [ poly (3-hydroxybutyrate) or poly (3-hydroxybutyrate) ], PHBH poly (3-hydroxybutyrate-co-3-hydroxyhexanoate), or poly (3-hydroxybutyrate-co-3-hydroxyhexanoate), PHBV [ poly (3-hydroxybutyrate-co-3-hydroxyvalerate) ] or poly (3-hydroxybutyrate-co-3-hydroxyvaleric acid) ], P3HB4HB [ poly (3-hydroxybutyrate-co-4-hydroxybutyrate) or poly (3-hydroxybutyrate-co 4-hydroxybutyrate) ], poly (3-hydroxybutyrate-co-3-hydroxyoctanoate) or poly (3-hydroxybutyrate-co-3-hydroxyoctadecanoate), and the like.

Examples of commercially available products of the above aliphatic polyester and derivatives thereof include: in the case of an aliphatic polyester obtained by polycondensation reaction between ethylene glycol (diol) and a polycarboxylic acid, PBS obtained from 1, 4-butanediol and succinic acid (for example, Bionore 1000 series (registered trademark: manufactured by Showa Denko K.K.), BiOPBS FZ series (registered trademark: manufactured by Mitsubishi chemical Co., Ltd.), PBSA obtained by copolymerizing adipic acid with PBS (for example, Bionore 3000 series (registered trademark: manufactured by Showa Denko K.K.), BiOPBS series (registered trademark: manufactured by Mitsubishi chemical Co., Ltd.), polyethylene glycol succinate (PES) obtained from ethylene glycol and succinic acid, poly (3-hydroxyalkanoate) of an aliphatic polyester copolymer obtained from hydroxyalkanoic acid and a polycarboxylic acid (in particular, poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) (for example, Aonilex (registered trademark: manufactured by Korea Co., Ltd.)), Examples of the copolymer of the aliphatic polyester and the terephthalate include PBAT (e.g., ECOFLEX (registered trademark)) which is a copolymer of 1, 4-butanediol and adipic acid and terephthalic acid, polybutylene terephthalate succinate (PBTS) (e.g., BioMax (registered trademark: manufactured by dupont)), PLA (e.g., revede (registered trademark), manufactured by Kaisei Biological Materials co., ltd., manufactured by ltd.), Ingeo (registered trademark) which is manufactured by Nature Works), Polycaprolactone (PCL) (e.g., CAPA6800 (registered trademark), manufactured by Perstop), and the like.

The content of the biodegradable resin contained in the filler layer 12 is preferably 50% by weight or more, more preferably 60% by weight or more, and still more preferably 70% by weight or more, based on the entire filler layer 12. When the content of the biodegradable resin in the filler layer 12 is 50 wt% or more, a part of the release paper 10 is biodegradable, and the environmental load can be reduced compared to the conventional case.

The packed layer 12 may contain a fossil fuel-derived polyolefin obtained by polymerizing a fossil fuel-derived monomer. The fossil fuel-derived monomer is not particularly limited, and examples thereof include: α -olefins such as ethylene, propylene, 1-butene, 2-methyl-1-pentene, 1-hexene, 2, 2-dimethyl-1-butene, 2-methyl-1-hexene, 4-methyl-1-pentene, 1-heptene, 3-methyl-1-hexene, 2, 2-dimethyl-1-pentene, 3-dimethyl-1-pentene, 2, 3-dimethyl-1-pentene, 3-ethyl-1-pentane, 2, 2, 3-trimethyl-1-butene, 1-octene, and 2, 2, 4-trimethyl-1-octene. These fossil fuel-derived monomers may be used alone or in combination of two or more. The main resin forming the filling layer 12 is preferably polyethylene.

The filling layer 12 preferably has a thickness of 0.5 μm or more and 50 μm or less, more preferably 5 μm or more and 50 μm or less. When the thickness of the filling layer 12 is less than 0.5 μm, it is difficult to suppress the penetration of the release agent into the paper base 11. On the other hand, if the thickness of the filling layer 12 exceeds 50 μm, the thickness becomes unnecessarily large, and it is not suitable for practical use.

Various additives and fillers such as clay, silica, calcium carbonate, titanium oxide, zinc oxide, and the like may be added to the filling layer 12 as necessary within a range not to impair the effects of the present invention.

The method for forming the filling layer 12 on one or both sides of the paper base 11 is not particularly limited, and examples thereof include conventionally known methods: a method of forming the filler layer 12 by applying a coating liquid containing a biodegradable resin and a biomass-derived resin on the paper base 11 and drying the coating liquid; a method of laminating the paper substrate 11 and the filler layer 12 by an adhesive; and a method of simultaneously extruding the paper base 11 and the filler layer 12 by a melt extrusion method to form the paper base. In the present embodiment, it is preferably formed by a melt extrusion method or a lamination method of an adhesive.

In the case of laminating the paper substrate 11 and the filler layer 12 by an adhesive, the adhesive used is not particularly limited, and examples thereof include: pressure sensitive adhesives, heat sensitive adhesives, laminating adhesives, and the like. In addition, from the viewpoint of the polymer constituting the adhesive, for example, an acrylic adhesive, a polyisocyanate-based adhesive, an epoxy-based adhesive, a rubber-based adhesive, or the like can be used. Among them, acrylic adhesives are particularly suitable because they are composed of a single component and have excellent transparency and good durability. As the acrylic adhesive, for example, an adhesive obtained by blending an appropriate crosslinking agent with a polymer obtained by copolymerizing acrylic acid, methacrylic acid, an acrylamide derivative, hydroxyethyl acrylate, glycidyl methacrylate, or the like can be used as the functional monomer serving as a crosslinking point, with n-butyl acrylate, 2-ethylhexyl acrylate, or the like as the main component, with methyl acrylate, ethyl acrylate, methyl methacrylate, styrene, acrylonitrile, vinyl acetate as the component for imparting cohesive force thereto. An adhesive obtained by blending.

The release paper 10 according to the present invention may further include a resin layer derived from fossil fuel. In particular, a polyolefin layer 14 of fossil fuel origin may be present. The polyolefin layer 14 derived from fossil fuel can improve filling properties, pinhole resistance, and the like. The fossil fuel-derived polyolefin layer 14 is a resin layer made of a resin material containing a fossil fuel-derived monomer, and the biomass degree of the fossil fuel-derived polyolefin layer 14 is 0%. Fig. 2 is a schematic cross-sectional view showing another embodiment of the release paper 10 according to the present invention. The release paper 10 includes: a paper base material 11; and a filler layer 12 which is provided on one or both surfaces of the paper base 11 and contains a biodegradable resin and a biomass-derived resin; and a fossil fuel-derived polyolefin layer 14 and a mold release layer 13 manufactured only from fossil fuel-derived raw materials. In addition, the release paper 10 may be a double-sided release paper (not shown) in which the filler layer 12 and/or the fossil fuel-derived polyolefin layer 14 and the release agent layer 13 are disposed on both sides of the paper substrate 11. The release paper 10 according to the present embodiment may be configured such that a curl suppression layer is provided on a surface of the paper base material 11 opposite to a surface on which the filler layer 12, the fossil fuel-derived polyolefin layer 14, and the release agent layer 13 are provided. The curl suppressing layer is not particularly limited, and may be, for example, the filler layer 12 or the polyolefin layer 14 derived from fossil fuel.

The fossil fuel-derived polyolefin layer 14 contains a polyolefin obtained by polymerizing the above fossil fuel-derived monomer. The fossil fuel-derived monomer may be used alone or in combination of two or more. The polyolefin of fossil fuel origin is preferably polyethylene obtained by polymerizing ethylene-containing monomers.

The polymerization method of the fossil fuel-derived polyolefin is not particularly limited, and may be carried out by a conventionally known method. The polymerization temperature and the polymerization pressure are preferably adjusted as appropriate depending on the polymerization method and the polymerization apparatus. Further, the polymerization apparatus is not particularly limited, and conventionally known apparatuses can be used.

The polyolefin layer 14 derived from fossil fuel preferably has a thickness of 0.1 μm or more and 30 μm or less. Further, the fossil fuel-derived polyolefin layer 14 may have two or more layers, each of which may have the same composition or different compositions.

Various additives and fillers such as clay, silica, calcium carbonate, titanium oxide, zinc oxide, and the like may be added to the fossil fuel-derived polyolefin layer 14 as needed within a range not to impair the effects of the present invention.

The method for forming the fossil fuel-derived polyolefin layer 14 on the filler layer 12 is not particularly limited, and conventionally known methods, for example, a method for forming the fossil fuel-derived polyolefin layer 14 by applying a fossil fuel-derived polyolefin coating solution on the filler layer 12 and drying the coating solution; and a method of simultaneously extruding the paper substrate 11, the filler layer 12, and the fossil fuel-derived polyolefin layer 14 by a melt extrusion method to form the paper substrate. In the present embodiment, it is preferably formed by a melt extrusion method.

In the release paper 10 of the present embodiment, the filling layer 12 functions as a so-called filling layer, and has an effect of suppressing the release agent in the release agent layer 13 from penetrating into the paper base material 11. Therefore, since the release paper 10 of the present embodiment has the filling layer 12, the release agent in the release agent layer 13 can be suppressed from penetrating into the paper base material 11.

(Release agent layer)

The release agent used in the release agent layer 13 according to the present embodiment is not particularly limited, and examples thereof include: silicone, fluorine, alkyd, long-chain alkyl resins, and various waxes. Among them, the release agent preferably contains a silicone-based release agent from the viewpoint of release characteristics. In addition, a biodegradable release agent such as that disclosed in Japanese patent laid-open No. 2002-212428 is preferably used.

Examples of the silicone release agent resin include: homopolymers or copolymers of trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, diphenyldichlorosilane, phenyltrichlorosilane, and methylvinyldichlorosilane, and the like. These resins may be used alone or in combination of two or more thereof. The silicone release agent may be used in any form of solvent type, solvent-free type, and emulsion type, but from the viewpoint of the environment, the emulsion type or solvent-free type is preferable.

The release agent layer 13 preferably has a thickness of 0.01 μm or more and 10 μm or less, more preferably 0.1 μm or more and 5 μm or less.

The method for applying the release agent to the filling layer 12 is not particularly limited, and various coating apparatuses such as a knife coater, an air knife coater, a bar coater, a gravure coater, a bar coater, and a multi-roll coater can be used.

The use of the release paper 10 according to the present embodiment is not particularly limited, and examples thereof include an adhesive layer (adhesive surface of a protective adhesive product) for protecting an adhesive sheet, an adhesive tape, a label, and the like.

(adhesive sheet)

The release paper 10 of the present embodiment can be used for an adhesive sheet obtained by adhering a base material for an adhesive sheet to the surface of the release agent layer 13 via an adhesive layer. The adhesive sheet can be easily manufactured by applying an adhesive to the surface of the release agent layer 13 of the release paper 10 of the present invention by a known method, drying the adhesive layer, and then adhering a base material for the adhesive sheet to the adhesive layer and winding the adhesive sheet.

The base material for an adhesive sheet according to the present embodiment is not particularly limited, and may be composed of a paper material or a resin film containing a resin material as a main component. Examples of the resin film include: resin films made from fossil fuel-derived raw materials, regenerated resin films made from regenerated resins, biomass resin films made from biomass-derived resins, and the like. As the base material for adhesive sheets, from the viewpoint of reducing environmental load, paper, a regenerated resin film made of regenerated resin, or a biomass resin film made of biomass-derived resin is preferable, and paper or biomass resin film is more preferable. Examples of the base material for paper-based adhesive sheets include: coated paper such as high-quality paper, art paper, coated paper such as coated paper, aluminum foil paper, colored paper, impregnated paper, glass paper, dust-free paper, etc. Examples of the resin used for the resin film include: polyester, polyethylene terephthalate, polyethylene, polylactic acid, polyurethane urea, vinyl chloride, polystyrene, polytetrafluoroethylene, polyimide, ABS, polyester synthetic paper, and the like. The base material for an adhesive sheet may be appropriately selected depending on the use as an adhesive sheet and the environment.

The adhesive used for the adhesive layer according to the present embodiment is not particularly limited, and examples thereof include: rubbers, acrylics, silicones, epoxies, polyesters, polyurethanes, polyolefins, vinyl ethers, or biomass adhesives containing biomass-derived materials, but biomass adhesives are particularly preferred from the viewpoint of reducing environmental load. Further, it may be a solvent-based adhesive, a non-solvent adhesive such as an emulsion-type adhesive and a hot-melt-type adhesive, or an energy ray-curable adhesive which is cured by irradiation of an energy ray and releasable.

In addition, the adhesive for an adhesive layer according to the present embodiment may be mixed with a tackifier, a softener, an age resistor, a filler, a colorant such as a dye or a pigment, and the like, as necessary. Examples of the tackifier include: rosin resins, terpene phenolic resins, terpene resins, aromatic hydrocarbon-modified terpene resins, petroleum resins, coumarone-indene resins, styrene resins, phenolic resins, xylene resins, and the like.

The adhesive layer according to the present embodiment preferably contains a tackifier. The tackifier is preferably one or more selected from rosin resins and terpene resins, which are plant-derived resins. When the tackifier contains one or more selected from rosin resins and terpene resins, which are plant-derived resins, the biomass content of the adhesive layer is increased. The biomass content of the adhesive layer according to the present embodiment is preferably 1.0% or more. The upper limit of the biomass content of the adhesive layer is preferably as large as possible, but is preferably 90% or less in practice.

The biomass adhesive is preferably formed from an emulsion-type adhesive composition containing an emulsion-type adhesive and an emulsion-type tackifier. The tackifier resin of the emulsion type tackifier contains at least one selected from rosin resin and terpene resin, and the biomass content of the adhesive layer is preferably 2.9% or more and less than 24.8%.

The adhesive sheet of the present embodiment can be applied to various purposes in the same manner as the conventional adhesive sheet, and for example, the adherend is molded into an appropriate shape such as a sheet, a tape, or a label to be bonded. Specific examples of adhesive sheets suitable for application to the present embodiment are illustrated below.

(base paper for label and label)

The release paper 10 of the present embodiment can be used as the label base paper 20. Fig. 3 is a schematic cross-sectional view showing one embodiment of a label base paper 20 using the release paper 10 according to the present invention. The label base paper 20 includes a release paper 10, an adhesive layer 21, and a label base 22. In addition, although not shown in the drawings, a conventionally known laminate film may be provided on the surface of the base material 22 for labels to protect the base material 22 for labels and prevent fading thereof.

Further, the label base paper 20 of the present embodiment may have a release paper 10, an adhesive layer 21, a label base 22, an adhesive layer 21, and a release paper 10 (not shown). Similarly to the above, a conventionally known laminate film (not shown) may be provided on the surface of the base material for label 22 to protect the base material for label 22 and prevent it from fading.

The adhesive used for the adhesive layer 21 according to the present embodiment is not particularly limited, and the same adhesive as that for the adhesive sheet described above can be used, but among them, a biomass adhesive is preferable from the viewpoint of reducing the environmental load. The biomass adhesive is preferably formed from an emulsion-type adhesive composition containing an emulsion-type adhesive and an emulsion-type tackifier. The adhesive layer 21 preferably contains a tackifier, which is one or more selected from rosin resins and terpene resins, and the biomass fraction of the adhesive layer 21 is preferably 1.0% or more.

The adhesive layer 21 preferably has a dry thickness of 5 μm or more and 200 μm or less, more preferably 10 μm or more and 100 μm. When the dry thickness is less than 5 μm, there may be cases where the adhesive strength is insufficient or the thickness of the adhesive layer 21 is difficult to be uniform. When the dry thickness exceeds 200 μm, drying time after coating of the adhesive may be consumed, or the adhesive may easily flow out from the base paper for label 20, thereby lowering the production efficiency.

The label substrate 22 according to the present embodiment is not particularly limited, and the same substrate as that used for the above-described adhesive sheet substrate can be used, but from the viewpoint of reducing environmental load, among them, paper, a regenerated resin film made of regenerated resin, or a biomass resin film made of biomass-derived resin is preferable, and paper or a biomass resin film is more preferable. The label base material 22 can be appropriately selected depending on the use and environment used as the label base paper 20. The label base material 22 is preferably a printing base material on which various printing means can print or print graphics, information, and the like.

In addition, from the viewpoint of improving the fixing property of toner, ink, or the like, the label base material 22 may further include a print receiving layer (not shown) on the surface on the side opposite to the adhesive layer 21.

The print-receiving layer can be provided by, for example, applying various coating agents for printing. As the coating agent for printing, acrylic resin, polyester resin, or a combination thereof is preferably used. From the viewpoint of reducing the environmental load, the coating agent for printing may be a coating agent composed of a biomass-derived resin.

Further, in the label base paper 20, a coating agent may be applied to the label base 22 or the print-receiving layer in order to protect toner, ink, and the like. Although there are no particular restrictions on the coating agent used, it is preferable to use a polyurethane-based resin or a polylactic acid-based resin derived from biomass, from the viewpoint of reducing the environmental load.

Further, by using the label base paper 20 of the present embodiment, the label of the present embodiment can be obtained by performing processing such as printing on the label base 22 and half-cutting or cutting the label base paper 20 as necessary.

In applications such as plastic bottles, labels that can be used as commodity displays, label packages, bottle cap seals, and integrated packages, a material having a high biomass resin content is required to be used in order to enhance environmental awareness and save resources. Therefore, the label base paper 20 of the present embodiment using the release paper 10 of the present embodiment is particularly suitable for such an application.

Examples

Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified, "%" and "part" represent "% by weight" and "part by weight".

(example 1)

First, the basis weight was 83g/m²On one side of the glassine paper, LLDPE (product name: SL118, manufactured by Braskem S.A., having a density of 0.916 g/cm) as a biomass source of biomass polyolefin was added³A mixture of 10 wt% of MFR 1.0g/10 min and 87% biomass, 45 wt% of fossil fuel-derived LDPE (0% biomass), and 45 wt% of fossil fuel-derived HDPE (0% biomass) was melt-extruded to form a biomass polyolefin layer having a thickness of 20 μm (8.7% biomass). Then, on the biomass polyolefin layer, a release agent layer having a thickness of 0.5 μm was formed with a silicone-based release agent to obtain a release paper. Then, an acrylic adhesive (trade name: PAT1, manufactured by Lintech Co., Ltd.) was applied to the release agent layer to a dry thickness of 20 μm by a casting method. Then, the sheet was stuck to polypropylene synthetic paper (product name: SGS-80, manufactured by Yupo Corporation) to prepare a tacky sheet.

(example 2)

First the basis weight was 78g/m²On both sides of the high-quality paper, byLLDPE (manufactured by Braskem S.A., trade name: SL118, density of 0.916 g/cm) as a biomass source of biomass polyolefin was used³A mixture of 10 wt% of MFR 1.0g/10 min and 87% biomass, 45 wt% of fossil fuel-derived LDPE (0% biomass), and 45 wt% of fossil fuel-derived HDPE (0% biomass) was melt-extruded to form a biomass polyolefin layer having a thickness of 20 μm (8.7% biomass). Then, on the biomass polyolefin layer, a release agent layer having a thickness of 0.5 μm was formed with a silicone-based release agent to obtain a release paper. Then, an acrylic adhesive (trade name: PAT1, manufactured by Lintech Co., Ltd.) was applied to the release agent layer to a dry thickness of 20 μm by a casting method. Then, the sheet was stuck to polypropylene synthetic paper (product name: SGS-80, manufactured by Yupo Corporation) to prepare a tacky sheet.

(example 3)

First, the basis weight was 83g/m²On one side of the glassine paper (E.g., glassine paper), PBS (polybutylene succinate) (a biomass-derived PBS (product name: BioPBS FZ91, manufactured by Mitsubishi chemical Co., Ltd.) having a density of 1.26g/cm, which is an aliphatic polyester resin as a biomass resin was added³MFR 5.0g/10 min, biomass degree 50%) 100 wt%, and a biomass PBS layer having a thickness of 17 μm was formed by melt extrusion. Then, on the biomass PBS layer, a release agent layer having a thickness of 0.5 μm was formed with a silicone-based release agent. Then, an acrylic adhesive (trade name: PAT1, manufactured by Lintech Co., Ltd.) was applied to the release agent layer to a dry thickness of 20 μm by a casting method. Then, the sheet was stuck to polypropylene synthetic paper (product name: SGS-80, manufactured by Yupo Corporation) to prepare a tacky sheet.

(example 4)

First, the basis weight was 83g/m²On one side of the glassine paper of (1), PBSA (polybutylene succinate-adipic acid) (biomass-derived PBS (product name: BioPBS FD92, manufactured by Mitsubishi chemical Co., Ltd.) as an aliphatic polyester resin as a biomass resin was coated with a coating solution of PBSA (polybutylene succinate-adipic acid) (BioPBS, product name: BioPBS, density: 1.24 g/cm)³MFR 4.0g/10 min, biomass degree 35%) 100 wt%, by melt extrusionThe method formed a biomass PBS layer with a thickness of 32 μm. Then, on the biomass PBSA layer, a release agent layer having a thickness of 0.5 μm was formed with a silicone-based release agent. Then, on the biomass PBS layer, a release agent layer having a thickness of 0.5 μm was formed with a silicone-based release agent. Then, an adhesive (trade name: PAT1, manufactured by Lintech Co., Ltd.) was applied to the release agent layer to a dry thickness of 20 μm by a casting method. Then, the sheet was stuck to polypropylene synthetic paper (product name: SGS-80, manufactured by Yupo Corporation) to prepare a tacky sheet.

(example 5)

An adhesive sheet was produced in the same manner as in example 1, except that the polypropylene-based synthetic paper (product name: SGS-80, manufactured by Yupo Corporation) in example 1 was changed to a polylactic acid-based film having a thickness of 50 μm (product name "Ecolode SA 50 μm thick", aliphatic polyester content 95 wt% or more, manufactured by Mitsubishi resin Corporation).

(example 6)

Except that the polypropylene-based synthetic paper (manufactured by Yupo Corporation, trade name: SGS-80) in example 1 was changed to a paper base (thickness: 80 μm, basis weight: 100 g/m)²The same procedure as in example 1 was repeated except for using high-quality paper).

(example 7)

An adhesive sheet was produced in the same manner as in example 1, except that the polypropylene-based synthetic paper (manufactured by Yupo Corporation, trade name: SGS-80) in example 1 was changed to a mechanically recycled polyester resin film (thickness: 50 μm, content of mechanically recycled polyester resin: 80% by weight, content of non-recycled resin: 20% by weight).

(example 8)

An adhesive sheet was produced in the same manner as in example 1, except that the adhesive in example 1 (trade name: PAT1, manufactured by linec corporation) was changed to the following emulsion-type adhesive.

(production of emulsion type adhesive)

In the production of the emulsion type adhesive, a reaction vessel equipped with a stirrer, a thermometer, a reflux cooler and a dropping funnel was used. In the reaction kettle, 55 wt% of ion exchange water was heated to 80 ℃ with stirring. Then, when the temperature of the ion-exchanged water reached 80 ℃, 0.1% by weight of ammonium persulfate was added as a polymerization initiator to prepare an aqueous ammonium persulfate solution.

In addition to the aqueous solution of ammonium persulfate, 60 wt% of 2-ethylhexyl acrylate, 38 wt% of butyl acrylate, and 2 wt% of acrylic acid were mixed with 1 wt% of an anionic reactive emulsifier (product name "New Frontier a-229E", manufactured by first industrial pharmaceutical company), and an appropriate amount of 25% aqueous ammonia for neutralization and 0.4 wt% ammonium persulfate were added to 43 wt% of ion exchange water and stirred with a stirrer, thereby obtaining a pre-emulsion.

Then, the pre-emulsion was added dropwise to the aqueous ammonium persulfate solution over 2 hours while maintaining the temperature in the reaction kettle at 80 ℃. Then, 1% by weight of persulfuric acid was added to terminate the polymerization reaction at a time point of 1 hour and a time point of 2 hours, respectively, after the completion of the dropwise addition of the pre-emulsion, thereby preparing an acrylic emulsion adhesive.

Then, emulsion type tackifier 1 (a tackifier resin having a product name "Hariester" manufactured by Harima chemical Co., Ltd., product number "SK-218 NS": a rosin resin, and a softening point of the tackifier resin: 100 ℃)10 wt% (converted to solid content), emulsion type tackifier 2 (a tackifier resin having a product name "Superester" manufactured by Mitsuwa chemical Co., Ltd., product number "E-730-55": a rosin resin, and a softening point of the tackifier resin: 125 ℃)0.5 wt% (converted to solid content), and emulsion type tackifier 3 (a tackifier resin having a product name "Superester" manufactured by Mitsuwa chemical Co., Ltd., product number "E-788": a rosin resin, and a softening point of the tackifier resin: 160 ℃)2.5 wt% (converted to solid content) were mixed with respect to 100 wt% (converted to solid content) of the acrylic emulsion type adhesive prepared, thereby preparing an emulsion type adhesive composition.

(comparative example 1)

At a basis weight of 83g/m²On one side of the glassine paper, byA mixture of 50 wt% of LDPE and 50 wt% of HDPE derived from fossil fuel is melt extruded to form a polyolefin layer having a thickness of 20 μm. Then, on the polyolefin layer, a release agent layer having a thickness of 0.5 μm was formed using a silicone-based release agent. Then, an adhesive (trade name: PAT1, manufactured by Lintech Co., Ltd.) was applied to the release agent layer to a dry thickness of 20 μm by a casting method. Then, the sheet was stuck to polypropylene synthetic paper (product name: SGS-80, manufactured by Yupo Corporation) to prepare a sample. The biomass degree of the polyolefin layer of the release paper is 0%.

< evaluation of Release Property >

The laminate of the base material for adhesive sheet and the adhesive layer was peeled off from each adhesive sheet. When the release paper was not broken and the laminate was peeled off, it was indicated by ∘, and when the release paper was broken, it was indicated by x. The results obtained in examples 1 to 8 and comparative example 1 are shown in Table 1.

[ Table 1]

As is apparent from table 1, example 1 using biomass polyolefin, example 2 using high-quality paper instead of glassine paper, examples 3 and 4 using biodegradable resin instead of biomass polyolefin, examples 5 to 7 using polylactic acid film, paper and mechanically recycled polyester resin film instead of polypropylene synthetic paper, and example 8 using biomass type adhesive instead of acrylic type adhesive, respectively, all showed good releasability equivalent to that of comparative example 1 using polyolefin derived from fossil fuel.

Accordingly, the present invention can provide a release paper, which is a release paper of a type comparable to conventional ones, and an adhesive sheet, a base paper for labels, and a label using the release paper.

While the present invention has been described above by using the embodiments and examples, it is needless to say that the technical scope of the present invention is not limited to the scope of the above embodiments and examples, and it is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments and examples. Further, as is apparent from the description in the claims, such various modifications or improvements are also included in the technical scope of the present invention.

Description of the reference numerals

10-release paper

11 paper substrate

12 filling layer

13 Release agent layer

14 polyolefin layer of fossil fuel origin

Base paper for 20 labels

21 adhesive layer

22 Label base Material