Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H19/00—Coated paper; Coating material
  • D21H19/80—Paper comprising more than one coating
  • D21H19/82—Paper comprising more than one coating superposed
  • D21H19/826—Paper comprising more than one coating superposed two superposed coatings, the first applied being pigmented and the second applied being non-pigmented
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H19/00—Coated paper; Coating material
  • D21H19/10—Coatings without pigments
  • D21H19/14—Coatings without pigments applied in a form other than the aqueous solution defined in group D21H19/12
  • D21H19/18—Coatings without pigments applied in a form other than the aqueous solution defined in group D21H19/12 comprising waxes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
  • B32B27/10—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of paper or cardboard
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/18—Layered products comprising a layer of synthetic resin characterised by the use of special additives
  • B32B27/20—Layered products comprising a layer of synthetic resin characterised by the use of special additives using fillers, pigments, thixotroping agents
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
  • B32B27/306—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl acetate or vinyl alcohol (co)polymers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/40—Layered products comprising a layer of synthetic resin comprising polyurethanes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D65/00—Wrappers or flexible covers; Packaging materials of special type or form
  • B65D65/38—Packaging materials of special type or form
  • B65D65/42—Applications of coated or impregnated materials
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H19/00—Coated paper; Coating material
  • D21H19/10—Coatings without pigments
  • D21H19/14—Coatings without pigments applied in a form other than the aqueous solution defined in group D21H19/12
  • D21H19/20—Coatings without pigments applied in a form other than the aqueous solution defined in group D21H19/12 comprising macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D21H19/22—Polyalkenes, e.g. polystyrene
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H19/00—Coated paper; Coating material
  • D21H19/36—Coatings with pigments
  • D21H19/38—Coatings with pigments characterised by the pigments
  • D21H19/40—Coatings with pigments characterised by the pigments siliceous, e.g. clays
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H19/00—Coated paper; Coating material
  • D21H19/36—Coatings with pigments
  • D21H19/44—Coatings with pigments characterised by the other ingredients, e.g. the binder or dispersing agent
  • D21H19/56—Macromolecular organic compounds or oligomers thereof obtained by reactions only involving carbon-to-carbon unsaturated bonds
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H19/00—Coated paper; Coating material
  • D21H19/36—Coatings with pigments
  • D21H19/44—Coatings with pigments characterised by the other ingredients, e.g. the binder or dispersing agent
  • D21H19/62—Macromolecular organic compounds or oligomers thereof obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H19/00—Coated paper; Coating material
  • D21H19/80—Paper comprising more than one coating
  • D21H19/82—Paper comprising more than one coating superposed
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D2565/00—Wrappers or flexible covers; Packaging materials of special type or form
  • B65D2565/38—Packaging materials of special type or form
  • B65D2565/381—Details of packaging materials of special type or form
  • B65D2565/387—Materials used as gas barriers

Definitions

• the present disclosure relates to a laminate having barrier properties and a processed paper product using the laminate.
• Packaging materials that have gas barrier properties such as oxygen barrier properties and water vapor barrier properties added to paper base materials have traditionally been used in the packaging of foods, medical products, electronic components, etc. to prevent the quality of the contents from deteriorating. It's been getting worse.
• a common method for imparting water vapor barrier properties and gas barrier properties to a paper base material is to laminate a synthetic resin film with excellent gas barrier properties onto the paper base material.
• materials in which a synthetic resin film or the like is laminated onto a paper base material have an environmental problem because it is difficult to recycle the paper or synthetic resin after use.
• JP 2021-138434A discloses a paper barrier material in which a gas barrier layer and a heat seal layer are provided in this order on a paper base material, in which the hydroxyl groups and acid groups of the resin used for the gas barrier layer are controlled. The technology is described.
• the paper barrier material described in JP-A-2021-138434 has a single barrier layer, making it possible to reduce the amount of plastic material. However, it cannot be said to be sufficient from the viewpoint of higher gas barrier properties or the coexistence of gas barrier properties and water vapor barrier properties.
• the present disclosure provides a laminate that is highly compatible with water vapor barrier properties and gas barrier properties, and can further improve the paper ratio (biomass ratio).
• the present disclosure relates to ⁇ 1> to ⁇ 18> below.
• a paper base layer, a barrier layer, and a sealant layer are provided in this order,
• the barrier layer contains a polyurethane resin, a flat inorganic compound with an average thickness of 50 nm or less and an average aspect ratio of 200 or more, and a cationic resin,
• the polyurethane resin is The laminate according to ⁇ 1>, comprising at least one selected from the group consisting of polyurethane having a constituent unit derived from metaxylylene diisocyanate and hydroxy polyurethane.
• ⁇ 3> The laminate according to ⁇ 1> or ⁇ 2>, wherein the flat inorganic compound contains a swellable layered silicate.
• ⁇ 4> The laminate according to any one of ⁇ 1> to ⁇ 3>, wherein the barrier layer contains 1.0 to 20.0% by mass of the cationic resin.
• ⁇ 5> The laminate according to any one of ⁇ 1> to ⁇ 4>, wherein the barrier layer contains 30.0 to 80.0% by mass of the polyurethane resin.
• ⁇ 6> The laminate according to any one of ⁇ 1> to ⁇ 5>, wherein the barrier layer contains 5.0 to 35.0% by mass of the flat inorganic compound.
• the barrier layer further includes at least one selected from the group consisting of a water-suspended polymer other than the polyurethane resin and a water-soluble polymer other than the polyurethane resin,
• the water-suspended polymer contains at least one selected from the group consisting of styrene/butadiene copolymers, styrene/acrylic copolymers, olefin/unsaturated carboxylic acid copolymers, and polyolefin resins.
• the barrier layer further includes at least one water-suspended polymer other than the polyurethane resin and at least one water-soluble polymer other than the polyurethane resin,
• the barrier layer is a laminate according to any one of ⁇ 1> to ⁇ 6>, including at least the water-suspending polymer and the water-soluble polymer in any combination of (A) to (E) below. body.
• the barrier layer comprises the water-suspended polymer other than the polyurethane resin and the water-soluble polymer other than the polyurethane resin.
• the laminate according to ⁇ 7> or ⁇ 8> containing a total of 1.0 to 50.0% by mass of polymers.
• Ratio of the mass of the polyurethane resin to the total mass of the water-suspended polymer other than the polyurethane resin and the water-soluble polymer other than the polyurethane resin in the barrier layer (mass of polyurethane resin: The laminate according to any one of ⁇ 7> to ⁇ 9>, wherein the total mass of the water-suspended polymer and the water-soluble polymer is 50:50 to 95:5.
• the sealant layer contains a water-dispersible resin.
• ⁇ 12> The laminate according to any one of ⁇ 1> to ⁇ 11>, wherein the wax contains at least one selected from the group consisting of hydrocarbon wax and ester wax.
• ⁇ 13> The laminate according to any one of ⁇ 1> to ⁇ 12>, wherein the wax contains at least one selected from the group consisting of paraffin wax, carnauba wax, and microcrystalline wax.
• the sealant layer contains a water-dispersible resin
• the laminate according to any one of ⁇ 1> to ⁇ 13>, wherein the water-dispersible resin contains at least one selected from the group consisting of a styrene-acrylic copolymer and a polyolefin resin.
• the sealant layer contains a water-dispersible resin
• the sealant layer contains a water-dispersible resin, The laminate according to any one of ⁇ 1> to ⁇ 15>, wherein the wax content in the sealant layer is 1 to 35 parts by mass based on 100 parts by mass of the water-dispersible resin.
• ⁇ 17> The laminate according to any one of ⁇ 1> to ⁇ 16>, wherein the wax content in the sealant layer is 1 to 30% by mass.
• ⁇ 18> A processed paper product using the laminate according to any one of ⁇ 1> to ⁇ 17>.
• the range “X to Y” means “X or more and Y or less”.
• gas barrier property means “oxygen barrier property” unless otherwise specified.
• (meth)acrylic refers to a generic term for acrylic and methacryl.
• operations and measurements of physical properties, etc. are performed under conditions of room temperature (20 to 25° C.)/relative humidity of 40 to 50% RH.
• One embodiment of the present disclosure includes a paper base layer, a barrier layer, and a sealant layer in this order, and the barrier layer is made of a flat inorganic compound made of a polyurethane resin and having an average thickness of 50 nm or less and an average aspect ratio of 200 or more. and a cationic resin, and the sealant layer includes wax.
• the laminate has high water vapor barrier properties and gas barrier properties, and can further improve the paper ratio (biomass ratio). Although the mechanism by which this effect is produced is unknown, it is assumed as follows.
• the barrier layer contains a polyurethane resin, a flat inorganic compound having an average thickness of 50 nm or less and an average aspect ratio of 200 or more, and a cationic resin.
• the laminate of this embodiment may have a barrier layer and a heat seal layer on only one side of the paper base layer in this order, or a barrier layer and a heat seal layer on both sides of the paper base layer in this order. may have.
• the laminate includes a paper base layer.
• the paper base material used for the paper base layer is not particularly limited, and any known paper material can be used.
• the pulp constituting the paper base material preferably has plant-derived pulp as its main component, and has wood pulp as its main component. Examples of the wood pulp include hardwood pulp and softwood pulp. Non-wood pulps include cotton pulp, hemp pulp, kenaf pulp, bamboo pulp, and the like. Materials other than pulp fibers, such as synthetic fibers such as rayon fibers and nylon fibers, may also be blended as sub-paper materials as long as they do not impair the effects of the present invention.
• the paper base material include bleached kraft paper, unbleached kraft paper, high-quality paper, paperboard, liner paper, coated paper, single-gloss bleached kraft paper, glassine paper, and graphene paper.
• bleached kraft paper unbleached kraft paper, high-quality paper, and single-gloss bleached kraft paper. More preferred are bleached kraft paper and single gloss bleached paper, and even more preferred is single gloss bleached kraft paper.
• the paper base material may contain additives.
• additives include pH adjusters (sodium hydrogen carbonate, sodium hydroxide, etc.), dry paper strength agents (polyacrylamide, starch, etc.), wet paper strength agents (polyamide polyamine epichlorohydrin resin, melamine-formaldehyde resin, (urea-formaldehyde resin), internal sizing agents (rosin type, alkyl ketene dimer, etc.), drainage retention improvers, antifoaming agents, fillers (calcium carbonate, talc, etc.), dyes, etc.
• pH adjusters sodium hydrogen carbonate, sodium hydroxide, etc.
• dry paper strength agents polyacrylamide, starch, etc.
• wet paper strength agents polyamide polyamine epichlorohydrin resin, melamine-formaldehyde resin, (urea-formaldehyde resin), internal sizing agents (rosin type, alkyl ketene dimer, etc.), drainage retention improvers, antif
• the basis weight of the paper base material may be changed as appropriate depending on the intended use of the laminate, and is not particularly limited. For example, for use in packaging bags, it is preferably 20 g/m 2 or more and 150 g/m 2 or less, more preferably 30 g/m 2 or more and 100 g/m 2 or less, and even more preferably 40 g/m 2 or more and 70 g/m 2 or less.
• the basis weight of the paper base material is measured in accordance with JIS P 8124:2011.
• the paper thickness of the paper base material may be changed as appropriate depending on the intended use of the laminate, and is not particularly limited. For example, for use in packaging bags, it is preferably 20 ⁇ m or more and 150 ⁇ m or less, more preferably 25 ⁇ m or more and 100 ⁇ m or less, and even more preferably 30 ⁇ m or more and 50 ⁇ m or less.
• the paper thickness of the paper base material is measured in accordance with JIS P 8118:2014.
• the smoothness of the paper base material is not particularly limited.
• the Oken type smoothness of the surface on which the barrier layer is provided is preferably 5 seconds or more, more preferably 10 seconds or more.
• the upper limit is not particularly limited, for example, it is preferably 2000 seconds or less, and more preferably 1000 seconds or less.
• the Oken smoothness of the paper base material is measured in accordance with JIS P 8155:2010.
• Examples of the method for manufacturing the paper base material include a method of making paper from a paper stock containing pulp.
• the paper stock may further contain an additive.
• Examples of the additive include the additives listed above.
• Paper stock can be prepared by adding additives to pulp slurry. Pulp slurry is obtained by beating pulp in the presence of water.
• the pulp beating method and beating device are not particularly limited, and may be the same as known beating methods and beating devices.
• the content of pulp in the paper stock is not particularly limited, and may be within a commonly used range. For example, it is 60% by mass or more and less than 100% by mass with respect to the total mass of the paper stock.
• Paper making can be carried out using standard methods. For example, there is a method in which paper stock is cast on a wire or the like, dehydrated to obtain a wet paper, and if necessary, multiple wet papers are stacked, and this single-layer or multi-layer wet paper is pressed and dried. . At this time, if a plurality of wet papers are not stacked, a single-layer paper will be obtained, and if a plurality of wet papers are stacked, a multi-layer paper will be obtained. When stacking a plurality of wet papers, an adhesive may be applied to the surface of the wet paper (the surface on which other wet papers are stacked).
• the laminate includes a barrier layer.
• the laminate preferably has a barrier layer on at least one surface of the paper base material.
• the barrier layer may be one layer or two or more layers, but from the viewpoint of manufacturing cost, one layer (single layer) is preferable.
• the barrier layer exhibits high water vapor barrier properties and gas barrier properties.
• the barrier layer includes polyurethane resin.
• the polyurethane resin is not particularly limited as long as it is a polymer having urethane bonds, and any known polyurethane resin may be used. From the viewpoint of achieving both water vapor barrier properties and gas barrier properties to a higher degree, it is preferable that the polyurethane resin contains at least one member selected from the group consisting of polyurethane and hydroxy polyurethane having a constituent unit derived from metaxylylene diisocyanate, and hydroxy polyurethane. More preferably, it contains polyurethane.
• Polyurethane resins are generally obtained by the reaction of polyisocyanates and polyols having two or more hydroxy groups, but "polyurethanes having structural units derived from metaxylylene diisocyanate” refer to polyurethanes containing metaxylylene diisocyanate as the polyisocyanate.
• the polyurethane resin obtained by the above reaction is indicated by using part or all of it.
• hydroxy polyurethane refers to a polyurethane resin having hydroxyl groups.
• the hydroxyl value of the hydroxy polyurethane is preferably 100 to 500 mgKOH/g, more preferably 150 to 400 mgKOH/g, and still more preferably 200 to 350 mgKOH/g.
• Hydroxy polyurethane may have acid groups.
• the acid value of the hydroxy polyurethane is preferably 50 to 100 mgKOH/g, more preferably 10 to 70 mgKOH/g, and even more preferably 15 to 60 mgKOH/g.
• the acid value and hydroxyl value of hydroxy polyurethane can be measured by a titration method in accordance with JIS K 1557:2007.
• the content of the structural units derived from metaxylylene diisocyanate is preferably 50 mol% or more with respect to the total amount of structural units derived from polyisocyanate.
• Such a polyurethane resin exhibits high cohesive force due to hydrogen bonding and the stacking effect of xylylene groups, and is therefore considered to have better gas barrier properties.
• the above content can be identified using a known analytical method such as 1 H-NMR.
• the glass transition temperature of the polyurethane resin is preferably 50°C or higher, more preferably 65°C or higher, even more preferably 90°C or higher, and even more preferably 110°C or higher, and the upper limit is not particularly limited, but is, for example, 200°C or lower. It is.
• the glass transition temperature of the polyurethane resin is a value measured in accordance with JIS K 7121:1987.
• hydroxy polyurethanes can be used. Examples include HPU W-001, HPU W-003, and HPU-W013A (all manufactured by Dainichiseika Kagyo Co., Ltd.). Furthermore, examples of the polyurethane having a structural unit derived from metaxylylene diisocyanate include Takelac WPB-341 (30) (manufactured by Mitsui Chemicals).
• the content of polyurethane resin (preferably hydroxy polyurethane) in the barrier layer is preferably 30.0 to 80.0% by mass, more preferably 40.0 to 75.0% by mass, and 50.0% by mass. It is more preferably from 70.0% by weight, even more preferably from 55.0 to 68.0% by weight, even more preferably from 60.0 to 66.0% by weight. Within the above range, it becomes easier to improve water vapor barrier properties and gas barrier properties. Further, within the above range, the strength of the barrier layer will be good, and when a heat sealing layer is provided on the barrier layer, the heat sealability will be good.
• the barrier layer may contain other resins in addition to the polyurethane resin to the extent that the above effects are not impaired.
• other resins include, but are not limited to, polyolefin resins (polyethylene, polypropylene, etc.), vinyl chloride resins, styrene resins, styrene/butadiene copolymers, acrylonitrile/styrene copolymers, acrylonitrile/butadiene copolymers, ABS resin, AAS resin, AES resin, vinylidene chloride resin, poly-4-methylpentene-1 resin, polybutene-1 resin, vinylidene fluoride resin, vinyl fluoride resin, fluororesin, polycarbonate resin, acetal resin, polyphenylene oxide resin , polyester resin (polyethylene terephthalate, polybutylene terephthalate, etc.), polyphenylene sulfide resin, polyimide resin, polysulfone resin, polyether sulfone resin,
• the barrier layer further contains at least one selected from the group consisting of water-suspended polymers other than polyurethane resins and water-soluble polymers other than polyurethane resins. It is preferable to include.
• the water-suspended polymer or water-soluble polymer can be selected from those mentioned above as other resins that can be used in the barrier layer.
• the water-suspended polymer other than polyurethane resin is at least selected from the group consisting of styrene/butadiene copolymer, styrene/acrylic copolymer, olefin/unsaturated carboxylic acid copolymer, and polyolefin resin. It is preferable to include one type.
• the water-suspended polymers may be used alone or in combination of two or more.
• Examples of water-soluble polymers other than polyurethane resins include vinyl alcohol polymers, polyalkylene imines, (meth)acrylic acid polymers, polyethylene glycols, polyacrylamides, polycarboxylic acids, water-soluble cellulose derivatives, etc. It is preferable to include at least one selected from the group consisting of vinyl alcohol polymers and (meth)acrylic acid polymers.
• the water-soluble polymers may be used alone or in combination of two or more.
• the three components of polyurethane resin, flat inorganic compound, and cationic resin are good in terms of barrier properties, but are not sufficient in terms of film formability of the barrier layer. Understood. Therefore, the present inventors improved the film-forming properties of the barrier layer by using a water-suspending polymer or a water-soluble polymer in addition to the three components of polyurethane resin, flat inorganic compound, and cationic resin. It has been found that the water vapor barrier properties and the gas barrier properties are further improved as a result.
• water-suspended polymers and water-soluble polymers other than polyurethane resins will be collectively referred to as film-forming aids.
• the barrier layer preferably contains a water-suspended polymer and a water-soluble polymer.
• the water-suspended polymer is preferably an olefin/unsaturated carboxylic acid copolymer, and more preferably an ethylene/(meth)acrylic acid copolymer.
• a vinyl alcohol polymer is preferable.
• the mass ratio of water-suspended polymer to water-soluble polymer (water-suspended polymer: water-soluble polymer) in the barrier layer is preferably 20:1 to 1:2, more preferably 10:1 to 1:2. :1 to 2:3, more preferably 5:1 to 3:4, even more preferably 4:1 to 4:5.
• the barrier layer contains a water-suspended polymer and a water-soluble polymer.
• at least a combination of the following (A) to (E) includes a water-suspended polymer and a water-soluble polymer.
• Styrene-butadiene copolymers are made by combining styrene compounds such as styrene, ⁇ -methylstyrene, vinyltoluene, pt-butylstyrene, and chlorostyrene with 1,3-butadiene, isoprene (2-methyl-1,3 -butadiene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, etc., and other compounds copolymerizable with these monomers. It is a copolymer. Styrene is preferred as the styrene compound, and 1,3-butadiene is preferred as the butadiene compound.
• the acid-modified styrene-butadiene copolymer binder includes LX407S12 (manufactured by Nippon Zeon Co., Ltd.).
• Styrene-acrylic copolymers are made by combining styrene compounds such as styrene, ⁇ -methylstyrene, vinyltoluene, pt-butylstyrene, and chlorostyrene with acrylic acid, methacrylic acid, (meth)acrylic ester, and (meth)acrylic acid ester. ) Emulsion polymerization of monomers consisting of acrylic compounds such as acrylamide propane sulfonic acid, sulfoalkyl sodium (meth)acrylate (alkyl group has 2 to 3 carbon atoms), and other compounds copolymerizable with these.
• the (meth)acrylic ester is preferably an acrylic alkyl ester, and the alkyl group preferably has 1 to 6 carbon atoms.
• styrene-acrylic copolymers can also be used.
• examples of the styrene-acrylic copolymer binder include JONCRYL HSL-9012 (manufactured by BASF).
• Olefin/unsaturated carboxylic acid copolymers include olefins, especially ⁇ -olefins such as propylene, or ethylene, and acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, butene tricarboxylic acid, etc.
• Unsaturated carboxylic acids such as acids, unsaturated polycarboxylic acid alkyl esters having at least one carboxy group, such as itaconic acid monoethyl ester, fumaric acid monobutyl ester, and maleic acid monobutyl ester, and copolymerizable with these. It is a copolymer obtained by emulsion polymerization of monomers made of other compounds.
• ethylene or ⁇ -olefin is preferred, and ethylene is more preferred.
• unsaturated carboxylic acid monomer acrylic acid, methacrylic acid, itaconic acid, fumaric acid, etc. are suitable.
• ethylene/(meth)acrylic acid copolymer is preferable, and ethylene/acrylic acid copolymer is more preferable.
• olefin/unsaturated carboxylic acid copolymer examples include, for example, an aqueous dispersion of an ethylene/acrylic acid copolymer ammonium salt such as Zaixen (registered trademark) AC (copolymerization ratio of acrylic acid 20%, Sumitomo It is commercially available as (manufactured by Seikasha) and can be easily obtained and used.
• Zaixen registered trademark
• AC copolymerization ratio of acrylic acid 20%, Sumitomo It is commercially available as (manufactured by Seikasha) and can be easily obtained and used.
• polyolefin resin a homopolymer or a copolymer of a monomer selected from the group consisting of ethylene and ⁇ -olefin is preferable, and polyethylene is more preferable.
• commercially available polyolefins can also be used.
• the polyolefin resin binder includes HYDRECT HS (manufactured by DIC).
• vinyl alcohol polymers include polyvinyl alcohol.
• the degree of saponification of polyvinyl alcohol is preferably 85.0 to 99.5 mol%, more preferably 90.0 to 99.0 mol%.
• alkyl-modified polyvinyl alcohols such as ethylene-modified polyvinyl alcohol are preferred.
• Commercially available polyvinyl alcohol can also be used. Examples include the EXCEVAL series (manufactured by Kuraray).
• Examples of the (meth)acrylic acid polymer include polyacrylic acid, polymethacrylic acid, and salts thereof.
• Examples of the salt include sodium poly(meth)acrylate and ammonium poly(meth)acrylate.
• Commercially available (meth)acrylic acid polymers can also be used.
• examples of the aqueous ammonium polyacrylate solution include Aron A-30 (manufactured by Toagosei Co., Ltd.).
• water-soluble polymers such as polyethylene glycol, water-soluble polyamide, polyacrylamide, polycarboxylic acid, and water-soluble cellulose derivatives can be used.
• the polycarboxylic acid include polymaleic acid, acrylic acid-maleic acid copolymer, and polyglucuronic acid. These may be used alone or in combination of two or more.
• water-soluble cellulose derivatives include methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, hydroxypropylcellulose, methylhydroxypropylcellulose, and methylhydroxyethylcellulose.
• the weight average molecular weight of the water-suspended polymer and water-soluble polymer is preferably 10,000 or more, more preferably 20,000 or more, and preferably 10,000,000 or less, more preferably 5,000,000 or less.
• the weight average molecular weight of the water-suspended polymer is measured using gel permeation chromatography (standard substance: polystyrene).
• the weight average molecular weight of the water-soluble polymer is measured using gel permeation chromatography (standard substance: polyethylene glycol).
• the total content of water-suspended polymers other than polyurethane resins and water-soluble polymers other than polyurethane resins in the barrier layer is preferably 1.0 to 50.0% by mass, and 5.0 to 45% by mass. It is more preferably 0% by weight, even more preferably from 10.0 to 35.0% by weight, even more preferably from 13.0 to 25.0% by weight. Within the above range, it becomes easier to improve water vapor barrier properties and gas barrier properties, and the heat sealability also becomes better.
• the content of the water-suspended polymer other than the polyurethane resin in the barrier layer is preferably 1.0 to 40.0% by mass, more preferably 5.0 to 30.0% by mass, and 8% by mass. It is more preferably .0 to 20.0% by weight, and even more preferably 10.0 to 15.0% by weight. Within the above range, it becomes easier to improve water vapor barrier properties and gas barrier properties, and the heat sealability also becomes better.
• the content of the water-soluble polymer other than the polyurethane resin in the barrier layer is preferably 1.0 to 20.0% by mass, more preferably 2.0 to 15.0% by mass, and 2.0% by mass.
• water vapor barrier properties and gas barrier properties can be more easily improved, and heat sealability can also be improved.
• the mass ratio (polyurethane resin: film-forming aid) of the polyurethane resin in the barrier layer and the film-forming aid (total of water-suspended polymers other than polyurethane resin and water-soluble polymers other than polyurethane resin) is: From the viewpoint of achieving both barrier properties (especially gas barrier properties) and film formability, preferably 50:50 to 95:5, more preferably 55:45 to 90:10, still more preferably 60:40 to 85:15, and More preferably, the ratio is 70:30 to 85:15.
• the barrier layer contains a flat inorganic compound having an average thickness of 50 nm or less and an average aspect ratio of 200 or more.
• the flat inorganic compound is, for example, flat.
• the flat inorganic compound can be easily laminated substantially parallel to the plane (surface) of the paper base material. In this case, since the area where the flat inorganic compound does not exist becomes small in the planar direction, the permeation of water vapor is likely to be suppressed.
• the flat inorganic compounds are arranged parallel to the plane of the paper base material in the thickness direction, water vapor in the layer passes through the layer while bypassing the flat inorganic compounds, and due to the labyrinth effect, the water vapor permeation is suppressed. As a result, the barrier layer tends to exhibit excellent water vapor barrier properties.
• the average thickness of the flat inorganic compound is 50 nm or less.
• the average thickness of the flat inorganic compound is preferably 30 nm or less, more preferably 20 nm or less, even more preferably 15 nm or less, and particularly preferably 10 nm or less.
• the smaller the thickness of the flat inorganic compound the greater the number of laminated flat inorganic compounds in the barrier layer, which can exhibit high water vapor barrier properties.
• the lower limit of the thickness of the flat inorganic compound is not particularly limited, it is preferably 0.5 nm or more, more preferably 1 nm or more, and even more preferably 2 nm or more.
• the average thickness of the flat inorganic compound contained in the barrier layer is determined as follows.
• An enlarged photograph of the cross section of the barrier layer is taken using an electron microscope. At this time, the magnification is set such that about 20 to 30 flat inorganic compounds are included in the screen. The thickness of each of the flat inorganic compounds within the screen is measured. Then, the arithmetic mean value of the obtained thicknesses is calculated and taken as the average thickness of the flat inorganic compound.
• the average length of the flat inorganic compound is preferably 0.2 ⁇ m or more and 100.0 ⁇ m or less. When the average length is 0.2 ⁇ m or more, the flat inorganic compounds are likely to be arranged in parallel to the paper base material. Further, when the average length is 100.0 ⁇ m or less, there is little concern that a part of the flat inorganic compound will protrude from the barrier layer.
• the average length of the flat inorganic compound is more preferably 30.0 ⁇ m or less, even more preferably 15.0 ⁇ m or less, and particularly preferably 10.0 ⁇ m or less.
• the lower limit is more preferably 0.2 ⁇ m or more, further preferably 1.0 ⁇ m or more, and even more preferably 3.0 ⁇ m or more.
• the average length of the flat inorganic compound contained in the barrier layer is determined as follows. An enlarged photograph of the cross section of the barrier layer is taken using an electron microscope. At this time, the magnification is set such that about 20 to 30 flat inorganic compounds are included in the screen. The length (major axis) of each flat inorganic compound in the screen is measured. Then, the arithmetic average value of the obtained lengths is calculated and set as the average length of the flat inorganic compound. Note that the length of the flat inorganic compound is sometimes described in terms of particle diameter.
• the flat inorganic compound has an average aspect ratio of 200 or more.
• the average aspect ratio of the flat inorganic compound is preferably 280 or more, more preferably 300 or more, even more preferably 500 or more, and even more preferably 800 or more.
• the upper limit of the average aspect ratio is not particularly limited, and from the viewpoint of the viscosity of the coating liquid, it is preferably about 10,000 or less, more preferably about 5,000 or less, even more preferably about 2,000 or less, and even more preferably about 1,500 or less. Even more preferred.
• the average aspect ratio is calculated by taking an enlarged photograph of the cross section of the barrier layer using an electron microscope and dividing the average length of the obtained flat inorganic compound by its average thickness. It is a value.
• flat inorganic compounds include mica such as mica group and brittle mica group, bentonite, kaolinite (kaolin mineral), pyrophyllite, talc, smectite, vermiculite, chlorite, septechlorite, serpentine, and still.
• examples include pnomeleine and montmorillonite.
• mica and bentonite examples include synthetic mica (e.g., swellable mica, non-swellable mica), muscovite, sericite, phlogopite, biotite, and fluorine.
• examples include phlogopite (artificial mica), red mica, soda mica, vanadium mica, illite, china mica, paragonite, and brittle mica.
• bentonite includes montmorillonite. These may be used alone or in combination of two or more.
• the planar inorganic compound comprises a swellable layered silicate such as swellable mica.
• the barrier layer comprises a hydroxy polyurethane and a swellable layered silicate.
• a swellable layered silicate is a layered inorganic compound that is swellable in water and whose layers are easily cleaved by shearing to a thickness on the order of nanometers.
• the swellable layered silicate examples include sodium tetrasilicon mica, sodium hectorite, lithium taeniolite, fluorophlogopite, sodium smectite, and sodium montmorillonite.
• the swellable layered silicate is preferably a swellable mica such as sodium tetrasilicate mica.
• examples of the swellable mica include NTS-10NC, NTO-05 (manufactured by Topy Industries), and Somasif ME300B-4T (manufactured by Katakura Co-op Agri).
• the content of the flat inorganic compound (preferably swellable layered silicate) in the barrier layer is preferably 5.0 to 35.0% by mass, and preferably 10.0 to 25.0% by mass. More preferably, it is 13.0 to 24.0% by mass. Within the above range, it becomes easier to improve water vapor barrier properties and gas barrier properties, and the heat sealability also becomes better.
• the barrier layer contains a cationic resin in addition to the polyurethane resin and the flat inorganic compound.
• a cationic resin By using a flat inorganic compound and a cationic resin together, gas barrier properties and water vapor barrier properties, particularly water vapor barrier properties, are greatly improved.
• the barrier layer contains a hydroxy polyurethane, a swellable layered silicate, and a cationic resin. This aspect allows extremely high water vapor barrier properties and gas barrier properties to be exhibited.
• Flat inorganic compounds tend to be anionically charged on the particle surface and cationically charged on the particle end surfaces, so the surface and end surfaces tend to attract each other and form a card house aggregate structure.
• a cationic resin By adding a cationic resin, the anionic groups on the particle surface can be blocked with cations, and the card house aggregate structure can be destroyed. Therefore, steric aggregation of the swellable phyllosilicate can be suppressed, the swellable phyllosilicate can be aligned parallel to the plane of the paper base material, and the labyrinth effect can be sufficiently expressed. As a result, extremely high gas barrier properties and water vapor barrier properties can be exhibited.
• cationic resins include polyamide compounds, modified polyamide compounds, polyamine compounds, modified polyamine compounds, polyamide amine-epihalohydrin or formaldehyde condensation reaction products, polyamine-epihalohydrin or formaldehyde condensation reaction products, polyamide polyurea-epihalohydrin.
• polyamine polyurea-epihalohydrin or formaldehyde condensation reaction product polyamine polyurea-epihalohydrin or formaldehyde condensation reaction product
• polyamide amine polyurea-epihalohydrin or formaldehyde condensation reaction product polyamide polyurea compound, polyamine polyurea compound, polyamide amine polyurea compound and polyamide amine
• examples include polyvinylpyridine, amino-modified acrylamide compounds, polyvinylamine, and polydiallyldimethylammonium chloride. These may be used alone or in combination of two or more.
• the cationic resin is preferably at least one selected from the group consisting of modified polyamide compounds and modified polyamine compounds, and is preferably at least one selected from the group consisting of modified polyamide resins and modified polyamine resins. It is more preferable.
• modified polyamide resins may be used, such as SPI203(50)H, manufactured by Taoka Chemical Industry, etc.
• modified polyamine resins such as SEIKOAT T-EF501 and those manufactured by Seiko PMC.
• the content of the cationic resin in the barrier layer may be appropriately selected depending on the type of material used for the barrier layer, such as hydroxy polyurethane and swellable layered silicate. From the viewpoint of further improving barrier properties (particularly gas barrier properties) and heat sealing properties, the content of the cationic resin in the barrier layer is preferably 1.0 to 20.0% by mass, and 1.0 to 10.0% by mass. It is more preferably 0% by mass, even more preferably from 1.5 to 8.0% by mass, even more preferably from 1.8 to 5.0% by mass, and even more preferably from 2.0 to 3.0% by mass. Particularly preferred is mass %.
• the surface charge of the cationic resin is preferably 0.1 to 10 meq/g, more preferably 0.1 to 5.0 meq/g, and preferably 0.1 to 4.0 meq/g. It is more preferably 0.1 to 2.0 meq/g, even more preferably 0.2 to 1.5 meq/g.
• the surface charge of the cationic resin is at least the above lower limit, the effect of adding the cationic resin can be more fully obtained.
• the surface charge is below the above upper limit, the effect of the cationic resin can be more fully exhibited while suppressing aggregation of the swellable layered silicate. Note that the surface charge of the cationic resin is measured by the method described below.
• a sample polymer is dissolved in water to obtain a solution with a polymer concentration of 1 ppm.
• a charge analyzer Mutek PCD-04 manufactured by BTG
• 0.001N sodium polyethylene sulfonate is added dropwise to the solution to measure the amount of charge.
• Dispersants, surfactants, antifoaming agents, wetting agents, dyes, color adjusters, thickeners, etc. may be added to the barrier layer as necessary to the extent that the above-mentioned specific barrier properties are not impaired. is possible.
• the coating amount of the barrier layer is not particularly limited, but from the viewpoint of barrier properties and redisintegration properties, the solid content after drying is preferably 1 to 15 g/m 2 , more preferably 2 g/m 2 or more. And, it is more preferably 10 g/m 2 or less, still more preferably 8 g/m 2 or less, even more preferably 6 g/m 2 or less.
• the thickness of the barrier layer is preferably 1 to 20 ⁇ m, more preferably 2 to 10 ⁇ m.
• the method of forming the barrier layer is not particularly limited. For example, coating a barrier layer in which at least one resin selected from the group consisting of water-suspended polymers and water-soluble polymers other than polyurethane resins, polyurethane resins, flat inorganic compounds, and cationic resins are dispersed in a solvent. Prepare the liquid. It is preferable to apply the obtained barrier layer coating liquid to a paper base material and dry it to form a barrier layer.
• the solvent for the barrier layer coating solution is not particularly limited, and water or organic solvents such as ethanol, isopropyl alcohol, methyl ethyl ketone, and toluene can be used.
• an aqueous medium is preferable as a dispersion medium for the barrier layer coating liquid, and water is more preferable.
• the aqueous medium is a medium containing 50% by mass or more of water.
• the device used for coating the barrier layer coating solution is not particularly limited, and may be appropriately selected from commonly used coating devices.
• coating devices For example, air knife coater, blade coater, gravure coater, rod blade coater, roll coater, reverse roll coater, Meyer bar coater, curtain coater, die slot coater, Champlex coater, metering blade type size press coater, short dwell coater,
• Various known coating devices such as a spray coater, a gate roll coater, and a lip coater can be used.
• the barrier laminate further has a sealant layer on the side on which the barrier layer is laminated.
• the sealant layer is a layer that is melted and bonded by heating, ultrasonic waves, or the like.
• the sealant layer preferably contains a water-dispersible resin.
• water-dispersible resins include those mentioned above as water-dispersible polymers other than polyurethane resins, preferably polyolefin resins, styrene-acrylic copolymers, ethylene-(meth)acrylic acid copolymers, etc. Examples include acrylic resins, ethylene-vinyl acetate copolymers, polyester resins, rubber resins, urethane resins, and polyamide resins.
• the content of the water-dispersible resin in the sealant layer is preferably 70 to 99% by mass, more preferably 80 to 98% by mass, and even more preferably 92 to 98% by mass from the viewpoint of heat sealability.
• the sealant layer is preferably a layer containing at least one resin selected from the group consisting of a styrene-acrylic copolymer and a polyolefin resin.
• a styrene-acrylic copolymer and polyolefin resin those described above for the water-suspended polymer can be used.
• Commercially available materials include an aqueous dispersion of styrene-acrylic copolymer (product name: SEIKOAT RE-2016, product name: XP8829, manufactured by Seiko PMC), an aqueous dispersion of polyolefin resin (product name: Rhobarr320, manufactured by Dow) ), etc.
• the sealant layer contains wax. Due to the film-forming effect of the wax, it exhibits extremely excellent water vapor barrier properties.
• the wax is not particularly limited, and any known wax can be used. From the viewpoint of high barrier properties, the wax preferably contains at least one selected from the group consisting of hydrocarbon waxes and ester waxes.
• Such waxes include the following: For example, natural waxes such as waxes of animal or vegetable origin (e.g., beeswax, carnauba wax, candelilla wax, etc.), mineral waxes, petroleum waxes (e.g., microcrystalline wax, etc.); polyolefin waxes, paraffin waxes, polyester waxes, etc.
• Synthetic waxes such as monoester waxes made from aliphatic monocarboxylic acids and aliphatic monoalcohols, diester waxes made from aliphatic monocarboxylic acids and aliphatic diols, diester waxes made from aliphatic dicarboxylic acids and aliphatic monoalcohols, etc. Examples include ester waxes. These may be used alone or in combination of two or more.
• At least one wax selected from the group consisting of paraffin wax, carnauba wax, and microcrystalline wax is included.
• Carnauba waxes can include, for example, ester waxes, hydrocarbons, and the like. Polyolefin wax, paraffin wax, microcrystalline wax, etc. fall under hydrocarbon wax.
• Carnauba wax may be either a synthetic product or a commercially available product. Commercially available products include Michem Lube-160RPH, manufactured by Michael Mann, and Cellosol 524, manufactured by Chukyo Yushi Co., Ltd. Paraffin wax may be either a synthetic product or a commercially available product.
• commercially available products include AQUACER497 manufactured by BYK and Hydrin L-700 manufactured by Chukyo Yushi Co., Ltd.
• As the microcrystalline wax either a synthetic product or a commercially available product may be used.
• Commercially available products include EMUSTAR-0001 manufactured by Nippon Seirosha.
• As the polyethylene wax either a synthetic product or a commercially available product may be used, and examples of the commercially available product include Aquacer 531 manufactured by BYK.
• the sealant layer preferably contains a water-dispersible resin and wax.
• the wax content in the sealant layer is preferably 1 to 35 parts by weight, more preferably 2 to 20 parts by weight, even more preferably 3 to 12 parts by weight, and 3 to 8 parts by weight based on 100 parts by weight of the water-dispersible resin. is even more preferred. By being within the above range, it is easy to achieve both high water vapor barrier properties and gas barrier properties, and furthermore, heat seal strength can be increased.
• the content of wax in the sealant layer is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, and even more preferably 2 to 8% by mass from the viewpoint of heat sealability.
• the sealant layer contains at least a water-dispersible resin and a wax in combination with any one of the following (A) to (D).
• D water-dispersible resin: polyolefin resin, wax: paraffin wax
• the sealant layer may further contain other components in addition to the water-dispersible resin and wax described above.
• Other components include pigments, dyes, crosslinking agents, coupling agents, surfactants, water-soluble polymers, etc., and known components can be used.
• the coating amount of the sealant layer is not particularly limited, but from the viewpoint of heat-sealability and redisintegration property, the solid content after drying is preferably 1 to 15 g/m 2 or less, more preferably 2 g/m 2 or more, and more preferably 10 g/m 2 or less, still more preferably 8 g/m 2 or less, and even more preferably 6 g/m 2 or less.
• the thickness of the sealant layer is preferably 0.5 to 20 ⁇ m, more preferably 1 to 10 ⁇ m.
• the method of forming the sealant layer is not particularly limited.
• a sealant layer coating liquid is prepared by dispersing a water-dispersible resin in a solvent. It is preferable to apply the obtained sealant layer coating liquid onto the barrier layer and dry it to form a sealant layer.
• the solvent for the sealant layer coating liquid is not particularly limited, and water or organic solvents such as ethanol, isopropyl alcohol, methyl ethyl ketone, and toluene can be used. Among these, from the viewpoint of not causing the problem of volatile organic solvents, an aqueous medium is preferable as a dispersion medium for the sealant layer coating liquid, and water is more preferable.
• the total coating weight of the barrier layer and the sealant layer is preferably 12 g/m 2 or less, more preferably 11 g/m 2 or less. Being within the above range means that even if the layer is thin, it can exhibit very high gas barrier properties and water vapor barrier properties. In addition, within the above range, the ratio of the paper base material can be easily increased, the weight of the product can be further reduced, and the biodegradation performance can be further improved.
• the lower limit of the coating amount is not particularly limited, but is preferably 2 g/m 2 or more, more preferably 5 g/m 2 or more, and still more preferably 8 g/m 2 or more. Therefore, the total coating weight of the barrier layer and the sealant layer is preferably 2 to 12 g/m 2 , more preferably 5 to 11 g/m 2 .
• the heat seal peel strength was 2.0 N/15 mm when a sample obtained by heat sealing the sealant layers of the laminate under the conditions of 160 ° C., 0.2 MPa, and 1 second was peeled using a tensile tester. It is preferably at least 2.5 N/15 mm, more preferably at least 2.8 N/15 mm, even more preferably at least 3.0 N/15 mm. When the heat sealing strength is within the above range, it is possible to prevent the bag from breaking when transporting the contents.
• the upper limit is not particularly limited, but is preferably 10.0 N/15 mm or less, 7.0 N/15 mm or less, 5.0 N/15 mm or less, and 4.0 N/15 mm or less. Therefore, the heat seal peel strength is preferably 2.0 to 10.0 N/15 mm.
• the method for manufacturing the laminate is not particularly limited, and any known method may be used.
• the method for producing a laminate includes the step of first coating a barrier layer coating liquid on a paper base material to form a barrier layer.
• the process may include a step of forming a sealant layer by applying a sealant layer coating liquid to the surface of the paper base coated with the barrier layer.
• the formation of each layer is as described above. Note that each layer may be formed by sequentially applying and drying a coating liquid, or may be formed by simultaneously applying multiple layers and then drying.
• the drying equipment for drying each coating layer is not particularly limited, and any known equipment can be used. Examples of the drying equipment include a hot air dryer, an infrared dryer, a gas burner, and a hot plate.
• the laminate has at least a paper base material, a barrier layer, and a sealant layer in this order.
• the barrier laminate may be a laminate consisting only of a paper base material, a single barrier layer, and a sealant layer.
• the laminate according to this embodiment may include layers other than the layers described above.
• it may have a pigment coating layer, an adhesive layer, a primer layer, etc., if necessary.
• an inorganic material layer such as an aluminum vapor deposited layer.
• the laminate of this embodiment has a barrier layer and a heat seal layer in this order on one side of the paper base material, it may have a pigment coating layer on the other side of the paper base material.
• a pigment coating layer By providing a pigment coating layer, it is possible to improve the smoothness of the surface and reduce the frictional force against packaging machine parts such as sailors, and as a result, a laminate with excellent printability and packaging processing suitability can be obtained.
• the pigment coating layer preferably contains a pigment and a binder. From the viewpoint of exhibiting the above effects, it is preferable to apply calender treatment to the pigment coating layer under arbitrary conditions.
• the pigment contained in the pigment coating layer is not particularly limited, and examples include kaolin, clay, engineered kaolin, delaminated clay, calcined clay, heavy calcium carbonate, light calcium carbonate, talc, titanium dioxide, and barium sulfate. , calcium sulfate, zinc oxide, silicic acid, silicate, colloidal silica, satin white, and other inorganic pigments; solid type, hollow type, or core-shell type organic pigments. These may be used alone or in combination of two or more.
• the content of pigment in the pigment coating layer is not particularly limited, but is, for example, 50 to 85% by mass.
• the binder contained in the pigment coating layer is not particularly limited, but includes styrene-butadiene resin; acrylic resin such as methyl (meth)acrylate copolymer and styrene-(meth)acrylic copolymer; ethylene- Olefin-unsaturated carboxylic acid copolymers such as (meth)acrylic acid copolymers; dextrin, mannan, chitosan, arabinogalactan, glycogen, inulin, pectin, hyaluronic acid, hydroxyethylated starch, oxidized starch, etherification Examples include natural polysaccharides such as starch, phosphoric acid esterified starch, enzyme-modified starch, and modified starch obtained by flash-drying these, oligomers thereof, and modified products thereof. These may be used alone or in combination of two or more.
• the content of the binder in the pigment coating layer is not particularly limited, but is, for example, 5 to 50% by mass
• the pigment coating layer may contain components such as adhesives, dispersants, thickeners, water retention agents, antifoaming agents, water resistance agents, colorants, and surfactants. .
• the coating amount (in terms of solid content) of the pigment coating layer is not particularly limited, but is, for example, 3 to 30 g/m 2 .
• the method of forming the pigment coating layer is not particularly limited, but it is preferably formed by coating a dispersion containing a pigment and a binder onto a paper base material and drying it.
• the water vapor permeability of the barrier laminate measured at 40° C. and 90% RH in accordance with JIS-Z-0208:1976 is less than 50 g/m 2 ⁇ day. It is preferable.
• the water vapor permeability is more preferably 30 g/m 2 ⁇ day or less, even more preferably 20 g/m 2 ⁇ day or less, even more preferably 15 g/m 2 ⁇ day or less, and 10 g/m 2 ⁇ day or less.
• /m 2 ⁇ day or less is especially preferable, it is especially preferable that it is 8 g/m 2 ⁇ day or less, and it is very preferable that it is 6 g/m 2 ⁇ day or less.
• a content within the above range indicates that the water vapor barrier property is extremely high.
• the lower limit is not particularly limited as the lower the better, but it is preferably 0 g/m 2 ⁇ day or more, 1 g/m 2 ⁇ day or more, or 2 g/m 2 ⁇ day or more.
• the water vapor permeability can be controlled, for example, by selecting the thickness of the barrier layer and the components contained in the barrier layer. Therefore, the water vapor permeability is preferably 0 g/m 2 ⁇ day or more and less than 50 g/m 2 ⁇ day, and may be 1 to 30 g/m 2 ⁇ day.
• the oxygen permeability of the laminate at 23° C. and 50% RH is preferably 10.0 mL/m 2 ⁇ day ⁇ atm or less.
• the oxygen permeability is preferably 8.0 mL/m 2 ⁇ day ⁇ atm or less, more preferably 5.0 mL/m 2 ⁇ day ⁇ atm or less, and 3.0 mL/m 2 ⁇ day ⁇ It is more preferably at most 2.0 mL/m 2 ⁇ day ⁇ atm, even more preferably at most 1.5 mL/m 2 ⁇ day ⁇ atm, even more preferably at most 1.0 mL/m 2 ⁇ day ⁇ atm.
• the oxygen barrier property is very high.
• the lower limit is not particularly limited because the lower the better, but it is preferably 0.0 mL/m 2 ⁇ day ⁇ atm or more, and 0.1 mL/m 2 ⁇ day ⁇ atm or more.
• the oxygen permeability can be controlled, for example, by selecting the thickness of the barrier layer and the components contained in the barrier layer. Therefore, the oxygen permeability is preferably 0.0 to 10.0 mL/m 2 ⁇ day ⁇ atm, and may be 0.1 to 8.0 mL/m 2 ⁇ day ⁇ atm.
• the oxygen permeability of the laminate at 23°C and 85% RH is preferably 10.0 mL/m 2 ⁇ day ⁇ atm or less, and preferably 8.0 mL/m 2 ⁇ day ⁇ atm or less. More preferably, it is 5.0 mL/m 2 ⁇ day ⁇ atm or less, even more preferably 3.0 mL/m 2 ⁇ day ⁇ atm or less, and even more preferably 2.0 mL/m 2 ⁇ day ⁇ atm. It is particularly preferably below, even more preferably below 1.5 mL/m 2 ⁇ day ⁇ atm, particularly preferably below 1.0 mL/m 2 ⁇ day ⁇ atm.
• the lower limit is not particularly limited because the lower the better, but it is preferably 0.0 mL/m 2 ⁇ day ⁇ atm or more, and 0.1 mL/m 2 ⁇ day ⁇ atm or more. Therefore, the oxygen permeability is preferably 0.0 to 10.0 mL/m 2 ⁇ day ⁇ atm, and may be 0.1 to 8.0 mL/m 2 ⁇ day ⁇ atm.
• the fact that the oxygen permeability at 85% RH satisfies the above range indicates that sufficient gas barrier properties are exhibited even in a high humidity environment.
• the oxygen permeability at 85% RH can be set within the above range by selecting the material used for the barrier layer.
• the weight ratio of the paper base material is a value obtained by calculating a 100% ratio as described below based on the total weight of the laminate.
• (Ratio of weight of paper base material) (weight of paper base material) / (weight of laminate) x 100
• the weight ratio of the paper base material is preferably 75% or more, more preferably 80% or more, and even more preferably 82% or more.
• the upper limit is not particularly limited, but is usually 99% or less, preferably 95% or less. Therefore, the weight proportion of the paper base is preferably between 75 and 99%.
• the laminate Since the laminate has very high water vapor barrier properties and gas barrier properties, it can be suitably used as a processed paper product.
• processed paper products include packaging bags, paper containers, and paper cups.
• the laminate can be suitably used as paper processed products such as packaging materials for foods, cosmetics, daily necessities, medical products, electronic parts, and the like.
• the laminate can also be suitably used as a processed paper product such as a packaging material for contents having a fragrance or odor. It can also be suitably used as paper processed products such as packaging materials for foods, cosmetics, daily necessities, medical products, electronic parts, etc. that are exposed to high humidity conditions.
• the laminate may be a barrier laminate.
• the packaging bag can be obtained by folding or overlapping two barrier laminates of this embodiment so that the heat-sealing layers face each other, and then heat-sealing the peripheral edges thereof.
• packaging bag formats include standing pouch type, side seal type, two side seal type, three side seal type, four side seal type, envelope sticker type, gassho sticker type (pillow seal type), pleated seal type, Examples include flat bottom seal type, square bottom seal type, and gusset type.
• Example 1 Aqueous dispersion of flat inorganic compound (swellable mica, average thickness 5 nm, average length (major axis) 6.3 ⁇ m, average aspect ratio 1260, solid content concentration 6% by mass, product name: NTS-10NC, manufactured by Topy Industries) ), 5.1 parts of a self-emulsifying emulsion of ethylene/acrylic acid copolymer (solid content concentration 29.2% by mass, product name: Zaixen AC, manufactured by Sumitomo Seika Chemicals) was added to 33.3 parts of ethylene/acrylic acid copolymer while stirring.
• flat inorganic compound swellable mica, average thickness 5 nm, average length (major axis) 6.3 ⁇ m, average aspect ratio 1260, solid content concentration 6% by mass, product name: NTS-10NC, manufactured by Topy Industries
• Zaixen AC a self-emulsifying emulsion of ethylene/acrylic acid copolymer
• a self-emulsifying aqueous emulsion of hydroxy polyurethane solid content concentration 30% by mass, product name: HPU-W013A, manufactured by Dainichiseika Industries, hydroxyl value 235 mgKOH/g, acid value 30 mgKOH/g, glass transition temperature 70°C) 26. 7 parts were added and stirred. To this was added 0.57 parts of modified polyamide resin (surface charge 0.4 meq/g, solid content concentration 53% by mass, product name: SPI203(50)H, manufactured by Taoka Chemical Industries) and stirred.
• the above barrier layer paint was applied to one side of a paper base material of 50 g/m 2 (single gloss bleached, manufactured by Oji F-Tex Co., Ltd.) at a solid content of 5 g/m 2 and blown with air at 120°C for 1 minute. Dry. Further, a sealant layer paint was applied on the barrier layer to a solid content of 5 g/m 2 and dried with air at 120° C. for 1 minute to obtain a heat-sealable laminate.
• Example 2 Heat treatment was carried out in the same manner as in Example 1, except that the self-emulsifying emulsion of ethylene/acrylic acid copolymer in the barrier layer coating was 13.7 parts, and the self-emulsifying aqueous emulsion of hydroxypolyurethane was 20.0 parts. A sealable laminate was obtained.
• Example 3 A heat-sealable laminate was obtained in the same manner as in Example 1, except that the amount of swellable mica in the barrier layer coating was 50 parts.
• Example 4 A heat-sealable laminate was obtained in the same manner as in Example 1, except that the paper base material was unbleached kraft paper 70 g/m 2 (unbleached light packaging paper, manufactured by Oji Materia).
• Example 5 A heat-sealable laminate was obtained in the same manner as in Example 1, except that the cationic resin in the barrier layer coating was changed to 1.89 parts.
• Example 6 Examples except that the cationic resin of the barrier layer paint was 0.60 part of a modified polyamine resin (surface charge 1.3 meq/g, solid content concentration 50% by mass, product name: SEIKOAT T-EF501, manufactured by Seiko PMC) A heat-sealable laminate was obtained in the same manner as in Example 1.
• a modified polyamine resin surface charge 1.3 meq/g, solid content concentration 50% by mass, product name: SEIKOAT T-EF501, manufactured by Seiko PMC
• Example 7 Other than changing the self-emulsifying emulsion of ethylene-acrylic acid copolymer to 3.8 parts of styrene-acrylic copolymer binder (solid content concentration 39% by mass, product name: JONCRYL HSL-9012, manufactured by BASF) A heat-sealable laminate was obtained in the same manner as in Example 1.
• Example 8 The self-emulsifying emulsion of ethylene/acrylic acid copolymer was changed to 3.3 parts of acid-modified styrene-butadiene copolymer (SBR) binder (solid content concentration 46% by mass, product name: LX407S12, manufactured by Zeon Corporation). Except for the above, a heat-sealable laminate was obtained in the same manner as in Example 1.
• SBR acid-modified styrene-butadiene copolymer
• Example 9 The same procedure as in Example 1 was carried out, except that the self-emulsifying emulsion of ethylene/acrylic acid copolymer was changed to 6.5 parts of a polyolefin resin binder (solid content concentration 23% by mass, product name: HYDRECT HS, manufactured by DIC Corporation). A heat-sealable laminate was obtained.
• Example 10 A heat-sealable laminate was obtained in the same manner as in Example 1, except that 10.0 parts of an aqueous solution of ethylene-modified polyvinyl alcohol dissolved in water to a solid content concentration of 10% by mass was added.
• Example 11 10.0 parts of an aqueous solution of ethylene-modified polyvinyl alcohol prepared by adjusting an aqueous solution of ammonium polyacrylate (solid content concentration 30% by mass, product name: Aron A-30, manufactured by Toagosei Co., Ltd.) to a solid content concentration of 5% by mass.
• a heat-sealable laminate was obtained in the same manner as in Example 1 except for the following changes.
• Example 12 Example 1 except that the styrene/acrylic copolymer aqueous dispersion of the sealant layer coating was changed to 73.2 parts of a polyolefin aqueous dispersion (solid content concentration 43% by mass, product name: Rhobarr 320, manufactured by Dow Company) In the same manner as above, a heat-sealable laminate was obtained.
• Example 13 A heat-sealable laminate was obtained in the same manner as in Example 1, except that the paraffin wax emulsion was 1.8 parts.
• Example 14 A heat-sealable laminate was obtained in the same manner as in Example 1 except that the paraffin wax emulsion was 6.0 parts.
• Example 15 Heat sealing was performed in the same manner as in Example 1, except that 6.0 parts of carnauba wax (solid content concentration 25% by mass, product name: Michem Lube-160RPH, manufactured by Michaelman) was used instead of the paraffin wax emulsion. A possible laminate was obtained.
• carnauba wax solid content concentration 25% by mass, product name: Michem Lube-160RPH, manufactured by Michaelman
• Example 16 The flat inorganic compound was changed from swelling mica to bentonite (sodium montmorillonite) (average thickness 1 nm, average length (major axis) 0.3 ⁇ m, average aspect ratio 300, product name: Kunipia G, manufactured by Kunimine Kogyo Co., Ltd.).
• a heat-sealable laminate was obtained in the same manner as in Example 1, except that an aqueous dispersion having a solid content concentration of 10% by mass was prepared and 20.0 parts were added.
• Example 17 A heat-sealable laminate was obtained in the same manner as in Example 1, except that the swellable mica and cationic resin in the barrier layer coating were changed to 100 parts and 5.7 parts, respectively.
• Example 18 A heat-sealable laminate was obtained in the same manner as in Example 1, except that the paraffin wax in the sealant layer coating was changed to 18.0 parts.
• Example 19 Heat treatment was carried out in the same manner as in Example 1, except that 3.8 parts of microcrystalline wax (solid content concentration 40% by mass, product name: EMUSTER-0001, manufactured by Nippon Seiro Co., Ltd.) was used instead of the paraffin wax emulsion. A sealable laminate was obtained.
• microcrystalline wax solid content concentration 40% by mass, product name: EMUSTER-0001, manufactured by Nippon Seiro Co., Ltd.
• Example 20 A self-emulsifying aqueous emulsion of hydroxy polyurethane (solid content concentration 30% by mass, product name: HPU-W013A, manufactured by Dainichiseika Kogyo Co., Ltd.) for the barrier layer coating was mixed with a dispersion of polyurethane having structural units derived from metaxylylene diisocyanate (A heat-sealable laminate was obtained in the same manner as in Example 1, except that the solid content concentration was 30% by mass, and the product name was changed to Takelac WPB-341 (30) (manufactured by Mitsui Chemicals).
• the content of the structural units derived from metaxylylene diisocyanate with respect to the total amount of structural units derived from polyisocyanate was 50 mol% or more. Further, the glass transition temperature of the polyurethane resin was 130°C.
• Comparative example 1 Heat-sealable in the same manner as in Example 1 except that the self-emulsifying emulsion of ethylene/acrylic acid copolymer in the barrier layer coating was 32.5 parts and the self-emulsifying aqueous emulsion of hydroxypolyurethane was 0 parts. A laminate was obtained.
• Comparative example 2 A heat-sealable laminate was obtained in the same manner as in Example 1 except that the amount of swellable mica in the barrier layer coating was 0 parts.
• Comparative example 3 A heat-sealable laminate was obtained in the same manner as in Example 1 except that the cationic resin in the barrier layer coating was 0 parts.
• Comparative example 4 A heat-sealable laminate was obtained in the same manner as in Example 1, except that the paraffin wax in the sealant layer coating was 0 parts.
• Comparative example 5 The flat inorganic compound was changed from swellable mica to engineered kaolin (average thickness 100 nm, average length 9 ⁇ m, average aspect ratio 90, product name: Varisurf HX, manufactured by Imerys), and the solid content concentration was 50% by mass.
• a heat-sealable laminate was obtained in the same manner as in Example 1, except that the aqueous dispersion was adjusted and 4.0 parts were added.
• Comparative example 6 To 47.3 parts of an aqueous dispersion of a layered inorganic compound (swellable mica, NTO-05), 90.0 parts of acid-modified SBR latex (LX407 S12) and acid-modified SBR latex (LX407BP-6) were added as an anionic binder while stirring. ) and stirred. To this, 4.5 parts of modified polyamide resin (SPI203 (50)) as a cationic resin was added and stirred. Furthermore, 0.6 part of 25% ammonia aqueous solution was added and stirred. Further, dilution water was added to make the solid content concentration 32%, and a coating liquid for a water vapor barrier layer was obtained.
• SPI203 modified polyamide resin
• a 10% solids concentration aqueous solution of polyvinyl alcohol (PVA, Poval PVA117) as a water-soluble polymer was prepared and used as a coating liquid for the gas barrier layer.
• the resulting water vapor barrier layer coating solution was applied onto one side of single-gloss bleached kraft paper using a Meyer bar so that the coating amount of the water vapor barrier layer after drying was 13 g/m 2 . , and dried in a hot air dryer at 120° C. for 1 minute to form a water vapor barrier layer.
• the coating solution for the gas barrier layer was applied on the water vapor barrier layer using a Mayer bar so that the coating amount after drying of the gas barrier layer was 2.0 g/m 2 , and then heated in a hot air dryer for 120 g/m2. °C for 1 minute to form a gas barrier layer. Furthermore, on the surface on which the oxygen barrier layer was formed, a water-based heat sealing agent (Chemipearl S-300, manufactured by Mitsui Chemicals) was applied to a solid content of 5 g/ m2 , and a sealant layer (thickness: 5 ⁇ m) was applied. ) to obtain a gas barrier laminate.
• a water-based heat sealing agent (Chemipearl S-300, manufactured by Mitsui Chemicals) was applied to a solid content of 5 g/ m2 , and a sealant layer (thickness: 5 ⁇ m) was applied.
• the oxygen permeability of the laminate was measured using an oxygen permeability measuring device (OX-TRAN2/22, manufactured by MOCON) under conditions of a temperature of 23° C. and a relative humidity of 50%.
• an isocyanate adhesive manufactured by DIC Corporation, 10 parts of DickDry LX-500 and 1 part of DickDry KW-75 was applied to the surface of the sealant layer of the laminates obtained in Examples and Comparative Examples).
• 5 g/m 2 of a 20 ⁇ m thick CPP film manufactured by Hokuetsu Kasei Co., Ltd., GP-32
• oxygen permeability was measured at a temperature of 23°C and a relative humidity of 50% and at a temperature of 23°C and a relative humidity of 85% in accordance with JIS K7126-2:2006.
• the heat-sealed test piece was cut into 15 mm width, and using a tensile tester, T-peel was performed at a tensile speed of 300 mm/min, and the maximum load recorded was determined as the heat-seal peel strength (N/15 mm). did.
• the formulations of the barrier layer and sealant layer in Tables 1 to 3 indicate the parts by mass of solid content.
• A indicates that single gloss bleached 50 g/m 2 was used, and B indicates that unbleached kraft paper 70 g/m 2 was used.

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