JP2006321495A - Liquid paper-container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid paper-container capable of preventing the heat sealability or the container strength even when filled and packaged with a liquid content containing chemicals having high permeability and diffusability, and avoiding any liquid leakage, and excellent in chemical resistance, heat resistance, barrier property for preventing permeation of gaseous oxygen, steam or the like, and pin-hole resistance. <P>SOLUTION: The liquid paper-container is formed of a laminate A in which at least an outermost layer 1, a paper base layer 2, an interposed resin layer 3, an intermediate layer 4, and an innermost layer 5 are successively laminated. The intermediate layer 4 to constitute the laminate consists of at least a barrier layer 4a, and/or a pin-hole resistant layer 4b. Further, the laminate A is interlaminated via a molten and extruded resin layer 8 between the intermediate layer 4 and the innermost layer 5. The innermost layer 5 is the laminate constituted of a resin layer containing a water-crosslinked ethylene copolymer with unsaturated silane compound introduced therein. By using the laminate, a container is manufacture. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  More specifically, with respect to the liquid paper container, it has excellent barrier properties that prevent permeation of oxygen gas, water vapor, etc., and further prevents the occurrence of pinholes, avoids sealing defects, liquid leakage, etc. Liquid paper that is filled with liquid contents containing chemicals as content components, such as alkaline contents, household detergents, car detergents, etc., and has excellent chemical resistance, storage stability, storage characteristics, etc. It relates to the container.

Conventionally, since a liquid paper container is a laminate mainly composed of paperboard, it has excellent disposal properties after use.For example, in milk, from the outside of a container, a polyethylene resin layer, a paper base material layer, a polyethylene film layer, Paper containers constructed by sequentially laminating are widely used.
Conventionally, as a layer structure of a laminated body constituting a liquid paper container for filling and packaging contents indispensable for barrier properties, a laminated body in which an aluminum foil having substantially zero gas permeability is laminated as an intermediate layer is used. For example, alcoholic beverages such as sake, shochu, and wine, and fruit juice beverages that require fragrance retention are packed and packaged, and the packaging products are widely distributed.

  In addition, a deposited resin film in which a deposited thin film layer of an inorganic oxide such as silicon oxide or aluminum oxide by a physical vapor deposition method such as a vacuum deposition method is formed on a plastic film is used as a barrier film and laminated It is known that a liquid paper container made of a body is also excellent in barrier properties (for example, Patent Document 1).

However, a liquid paper container composed of a laminate of aluminum foil is extremely superior in barrier properties, but when filled and packaged with a liquid content containing a chemical as a content component, it penetrates through the pinhole. There is a problem that the aluminum foil is corroded by the permeated component, or the aluminum foil is dissolved or disappeared by the alkaline component, and development of a liquid paper container having chemical resistance is urgently required.
Moreover, said vapor deposition resin film is inferior in flexibility, and there exists a problem that it does not have tolerance with respect to external stress, such as bending and bending. For example, in a liquid paper container, the barrier property is extremely deteriorated at the ruled line portion, and it is difficult to significantly improve the barrier property of the entire container. In addition, since the inorganic oxide vapor-deposited thin film layer is physically attached onto the plastic film substrate that is an organic substance, the adhesion between the inorganic oxide vapor-deposited thin film layer and the substrate is considerably poor. In the case of a highly permeable content, interfacial peeling may occur at one or both interfaces of the deposited inorganic oxide thin film layer during storage, which may cause problems such as liquid leakage.

Improves inter-layer adhesion with inorganic oxide vapor-deposited thin film layers that are barrier intermediate layers, improves barrier properties and content resistance, and has excellent resistance even when filled with contents containing chemicals As the liquid paper container having at least an outermost layer, a paper base material, an intermediate layer, and a laminate for a liquid paper container in which the innermost layer is sequentially laminated, the intermediate layer is made of a barrier film, and The barrier film is a vapor-deposited resin film in which a vapor-deposited thin film layer of silicon oxide containing silicon, oxygen, carbon, and hydrogen as film composition components is formed on at least one surface of a base film by a plasma vapor deposition method. And an adhesive layer or adhesive composed of a curable film made of a composition mainly composed of an epoxy resin composed of a curable film on the deposited thin film layer of silicon oxide constituting the deposited resin film. Liquid paper container made structure in which a fat layer is proposed (e.g., Patent Document 2).
Japanese Utility Model Publication No. 7-12466 JP 2003-335362 A

  However, in the above-described liquid paper container of Patent Document 1, when the liquid content containing chemicals having high permeability and diffusibility is filled and packaged, the liquid content having high permeability and diffusibility is absorbed from the innermost layer. As a result, the heat sealability is lowered and the strength of the entire paper container is lowered.

  The object of the present invention is to prevent liquid leakage and the like without reducing the heat sealability and the strength of the container even when filled and packed with a liquid content containing chemicals that are particularly permeable and diffusive. The object is to provide a liquid paper container excellent in chemical properties, heat resistance, barrier properties to prevent permeation of oxygen gas, water vapor, etc., and pinhole resistance.

  Therefore, in order to solve the above problems, the liquid paper container of the present invention is a laminate in which at least the outermost layer, the paper base layer, the intervening resin layer, the intermediate layer, and the innermost layer are sequentially laminated, The intermediate layer constituting the laminate is a laminate composed of at least a barrier layer and / or a pinhole-resistant layer, and is laminated via an adhesive resin layer between the intermediate layer and the innermost layer. And the innermost layer is a laminate composed of a resin layer containing a water cross-linked product of an ethylene copolymer into which an unsaturated silane compound is introduced, and the laminate is further used to produce the laminate. It is characterized by being boxed.

  According to the liquid paper container of the present invention, since the outermost layer and the innermost layer of the laminate constituting the liquid paper container are excellent in chemical resistance and heat resistance, in particular, alkaline contents, household detergents, car detergents, etc. Even if liquid contents containing chemicals are filled and packaged as a content ingredient, the heat-sealability and the strength of the container are not reduced, liquid leakage is avoided, and the contents are stored and stored. In addition, it has excellent barrier properties to prevent permeation of oxygen gas, water vapor, etc., pinhole resistance, heat sealability, and impact resistance.

Hereinafter, the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing an outline of the layer structure of a laminate for a liquid paper container according to the present invention.
First, when an example is illustrated about the laminated body for liquid paper containers concerning this invention, as shown in FIG. 1, the laminated body A for liquid paper containers concerning this invention is the outermost layer 1, the paper base material 2, The intermediate resin layer 3, the intermediate layer 4, and the innermost layer 5 are sequentially stacked, and the intermediate layer 4 includes a barrier layer 4a and / or a pinhole resistant layer 4b. The intermediate layer 4 and the innermost layer are formed by laminating the barrier layer 4a and the pinhole-resistant layer 4b via the dry laminate adhesive layer 6 and forming the anchor coat layer 7 on the intermediate layer 4 side. 5 is composed of a layer structure in which the layers 5 are laminated via the melt-extrusion adhesive resin 8.
Furthermore, it is necessary that the innermost layer 5 is composed of a resin layer or a synthetic resin film layer containing a water cross-linked product of an ethylene-unsaturated silane compound copolymer. Since the liquid paper container made by box making is excellent in chemical resistance and heat resistance, especially when filled with liquid content containing chemicals as content components such as alkaline content, household detergent, car detergent etc. , It has the advantage of excellent storage and storage.
The above exemplification illustrates an example of the layer structure of the laminate for a liquid paper container according to the present invention, and the present invention is not limited thereby.
For example, in the present invention, although not shown in the drawings, other base materials are optionally laminated in various forms depending on the purpose of packaging the liquid paper container, the contents to be filled and packaged, the distribution route, the use, etc. A laminated material can be designed and manufactured.

Next, in the present invention, an example of a liquid paper container obtained by using the above-described laminate for a liquid paper container according to the present invention and boxing it will be described. First, the liquid paper shown in FIG. Using a laminate for containers, according to the shape of the desired liquid paper container, according to the shape of the desired liquid paper container, a crease is engraved vertically or horizontally or diagonally and punched. A blank plate having an adhesive margin is manufactured.
Next, in order to prevent permeation of contents, liquid leakage, etc., on the end face of the blank plate produced as described above, for example, after performing end face treatment by applying a skive hemming treatment, etc. The surface of the other part of the blank plate is overlapped with the surface of the other part facing each other, and then, for example, a frame process or a hot air process is performed between the layers, and the glue margin part and the other part A cylindrical sleeve is manufactured by melting the resin layer constituting the innermost layer or the outermost layer at the end of the body and sealing the body with a frame seal or hot air seal through the molten surface. To do.
Next, the cylindrical sleeve manufactured above is supplied to the contents filling machine, and then, before filling the contents, first, the inner surface of the bottom of the cylindrical sleeve is heated with hot air. Then, the resin layer constituting the innermost layer on the inner surface is melted, and press sealing is performed to form a bottom seal portion, and a packaging container having an opening on the upper side is manufactured.
Then, after filling the contents from the opening of the packaging container manufactured above, the inner surface of the top is scrubbed with hot air, the resin layer constituting the innermost layer of the inner surface is melted, and press sealing is performed. Thus, for example, a liquid paper container is manufactured by forming a roof-type top seal portion and using the laminated body for a liquid paper container according to the present invention filled and packed with contents.
The above illustration is an example of the liquid paper container according to the present invention, and the present invention is not limited thereby.
For example, although not shown in the present invention, the shape of the liquid paper container according to the present invention can take any shape such as a gobeltop type, block type, cylindrical type, etc. It is.

Further, the outermost layer 1 formed on the paper substrate is particularly a melt-extruded resin layer having heat sealability that can be melted by heating and fused together, or a synthetic resin film layer. Specifically, for example, low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid resin, ethylene-acrylic Ethylene-unsaturated carboxylic acid such as ethyl acid copolymer, ethylene-methacrylic acid resin, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene resin, polybutene resin, ethylene-allyllic acid copolymer Copolymer-modified acid-modified polyolefin resin, polyvinyl acetate resin, poly (meth) acrylate System resin, polyvinyl chloride resin, other hot-melt resin.
The thickness of the outermost layer 1 is in the range of 8 μm to 60 μm, preferably 15 μm to 30 μm.

The paper base material 2 used in the present invention is a base material constituting the container, and has moldability, bending resistance, rigidity, waist, strength, and the like. Bleached or semi-bleached paper substrates, etc. can be used.
The basis weight of the paper substrate of about 50g / m ² ~700g / m ^2-position, preferably it is preferred to use a basis weight of 80g / m ² ~500g / m ² position.

Next, the desired printed pattern layer 9 can be formed on any of the materials constituting the laminate for a liquid paper container according to the present invention.
As the printed pattern layer, for example, on the above-mentioned paper substrate, a normal gravure ink composition, an offset ink composition, a letterpress ink composition, a screen ink composition, other ink compositions are used, for example, , Gravure printing method, offset printing method, letterpress printing method, silk screen printing method, and other printing methods, for example, by forming a desired printing pattern consisting of characters, figures, patterns, symbols, etc. be able to.
Regarding the ink composition, examples of the vehicle constituting the ink composition include polyolefin resins such as polyethylene resins and chlorinated polypropylene resins, poly (meth) acrylic resins, polyvinyl chloride resins, and polyvinyl acetate. Resin, vinyl chloride-vinyl acetate copolymer, polystyrene resin, styrene-butadiene copolymer, vinylidene fluoride resin, polyvinyl alcohol resin, polyvinyl acetal resin, polyvinyl butyral resin, polybutadiene resin, polyester resin Resins, polyamide resins, alkyd resins, epoxy resins, unsaturated polyester resins, thermosetting poly (meth) acrylic resins, melamine resins, urea resins, polyurethane resins, phenol resins, xylylene resins , Maleic resin, Fiber resins such as trocellulose, ethylcellulose, acetylbutylcellulose, ethyloxyethylcellulose, rubber resins such as chlorinated rubber and cyclized rubber, natural resins such as petroleum resins, rosin and casein, linseed oil, soybean oil, etc. A mixture of one or more of fats and oils and other resins can be used. In the present invention, one or more of the above-mentioned vehicles are used as a main component, and one or more of coloring agents such as dyes and pigments are added to this, and if necessary, a filler, Light stabilizers such as additives, plasticizers, antioxidants, UV absorbers, dispersants, thickeners, drying agents, lubricants, antistatic agents, cross-linking agents, and other additives are optionally added, solvent, dilution Ink compositions having various forms obtained by sufficiently kneading with an agent or the like can be used.

Next, the material of the innermost layer 5 has a heat seal property that can be melted by heating and fused to each other, and must have chemical resistance and heat resistance. A resin film containing a water cross-linked product of an ethylene-unsaturated silane compound copolymer such as “Product Name: Linkron, manufactured by Mitsubishi Oil Chemical Co., Ltd.” can be used.
The above resin film layer needs to contain a silane compound having a hydrolyzable organic group, and the active silane group in the polymer is in contact with water in liquid, vapor or air in the range of room temperature to about 100 ° C. By doing so, a cross-linking reaction is performed to form a network polymer.
As a method for producing the resin film layer, for example, a polyethylene resin composition containing a silanol condensation catalyst is kneaded with an extruder or the like in a molten state of about 150 ° C. to 300 ° C. It can be produced by water-crosslinking of a silane group introduced into the copolymer by contacting with water.
The thickness is in the range of 15 to 150 μm, preferably 30 to 100 μm.
Further, in the present invention, by using the resin as described above, this is melt-extruded using an extruder or the like, and the melt-extruded resin layer is melt-extruded and laminated through an anchor coat layer or the like. Alternatively, a resin film or sheet is produced in advance using the resin as described above, and the resin film or sheet is dried laminating through a laminating adhesive layer or the like. The innermost layer or the like can be formed by stacking the layers.

  In addition, when using one or more of the above-mentioned various resins and forming the film, for example, film processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness Various plastic compounding agents and additives can be added for the purpose of improving and modifying mold release properties, flame retardancy, antifungal properties, electrical properties, strength, etc. Can be arbitrarily added from a very small amount to several tens of percent depending on the purpose. In the above, general additives include, for example, colorants such as lubricants, crosslinking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, antistatic agents, lubricants, antiblocking agents, dyes, pigments, and the like. Others can be used, and a modifying resin or the like can also be used.

Next, in the present invention, the barrier layer 4a constituting the liquid paper container according to the present invention will be described. A material having a property of shielding light such as sunlight or a property of not transmitting water vapor, water, gas, etc. This may be a single base material, or a composite base material formed by combining two or more base materials.
Specifically, an aluminum foil is generally used as the material of the barrier layer, but instead of the aluminum foil, a metal such as aluminum, a ceramic such as silica or alumina, and a plastic film such as a polyethylene terephthalate film. In some cases, a deposited film is formed by vacuum deposition or sputtering.
In addition to these, indium tin oxide (ITO), metal oxides such as zinc, tin, titanium, zirconium, vanadium, barium, chromium, silicon nitride, silicon carbide, and the like can be used as the ceramic.
These materials can be used alone or in combination.
The thickness of the above film or sheet is arbitrary, but is usually preferably about 5 to 300 μm, and more preferably about 10 to 100 μm.
Furthermore, in the above, it is preferable to use an aluminum foil having a thickness of about 5 to 30 μm, and a metal or inorganic oxide deposition film having a thickness of about 50 to 3000 mm, preferably 100 to A thing of about 1000 mm is desirable.
As the metal or metal oxide to be used, it is also possible to use one or a mixture of two or more and form an inorganic oxide vapor-deposited film mixed with different materials.
In addition, the resin film that supports the above-described vapor-deposited film is provided with a vapor-deposited layer, and therefore has excellent properties in mechanical, physical, chemical, etc., particularly strong and tough. In addition, a heat-resistant resin film or sheet can be used.

Specifically, in the present invention, examples of the resin film that supports the above-described deposited film include polyester resin films such as polyethylene terephthalate, polyamide resin films such as various nylons, polyethylene resins, and polypropylene resins. Resin, cyclic polyolefin resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), polyolefin film such as polybutene resin film, polyvinyl chloride resin, polycarbonate Bonate resin, polyimide resin, polyamideimide resin, polyaryl phthalate resin, silicone resin, polysulfone resin, polyphenylene sulfide resin, polyethersulfone resin, polyurethane resin, cell Over scan resins, poly (meth) acrylic resins, polyvinylidene chloride film, acetal resin film, fluorine-based resin, it is possible to use other like.
In the present invention, it is particularly preferable to use a film or sheet of polypropylene resin, polyester resin, or polyamide resin.

In the present invention, a method for forming a vapor deposition film of metal or inorganic oxide will be described in detail. Using the metal or metal oxide as described above as a raw material, this is heated and vapor deposited on a flexible film. Vacuum deposition method or oxidation reaction deposition method that uses metal or metal oxide as raw material, oxidizes by introducing oxygen gas etc. and deposits on flexible film, and plasma that further assists oxidation reaction with plasma A vapor deposition film can be formed using an auxiliary oxidation reaction vapor deposition method or the like.
In the present invention, when a silicon oxide vapor deposition film is formed, the vapor deposition film can be formed by a plasma chemical vapor deposition method using organosiloxane as a raw material.

In the present invention, the layer 4b that imparts pinhole resistance constituting the intermediate layer exhibits excellent properties in mechanical, physical, chemical, etc., has excellent strength, and further has heat resistance, resistance to resistance. A film or sheet having excellent physical properties such as pinhole property and puncture resistance can be used.
Specifically, as a material for the layer imparting pinhole resistance, strong resin such as polyethylene resin, polypropylene resin, polyester resin, polyamide resin, polyaramid resin, polycarbonate resin, polyacetal resin, fluorine resin, etc. A film or sheet can be used.
Thus, as the resin film or sheet, any of an unstretched film or a stretched film stretched in a uniaxial direction or a biaxial direction can be used.
In the present invention, the thickness of the resin film or sheet may be a thickness that can be kept to the minimum necessary for strength, pinhole resistance, puncture resistance, rigidity, etc., and is too thick. In addition, there is a disadvantage that the cost increases. On the other hand, if it is too thin, the strength, puncture resistance, rigidity, etc. are undesirably lowered.
The thickness of the film is about 5 to 100 μm, preferably about 6 to 50 μm.

Next, in the present invention, a method for producing the laminate A for liquid paper containers according to the present invention using the above materials will be described. As such a method, for example, a method for laminating a normal packaging material, for example, The wet lamination method, the dry lamination method, the solventless dry lamination method, the extrusion lamination method, the T-die extrusion molding method, the coextrusion lamination method, the inflation method, the coextrusion inflation method, and the like.
And in this invention, when performing said lamination | stacking, if necessary, pre-treatments, such as a corona treatment, a plasma treatment, an ozone treatment, etc., can be given arbitrarily, for example, an isocyanate type ( Urethane), polyethyleneimine, polybutadiene, organic titanium and other anchor coating agents, or polyurethane, polyacrylic, polyester, epoxy, polyvinyl acetate, cellulose, and other adhesives for laminating A known anchor coating agent, an adhesive for laminating, and the like can be arbitrarily used.

In the present invention, the method for producing the laminate A for liquid paper containers according to the present invention will be specifically described. For example, a dry lamination method of laminating via a laminating adhesive layer with a laminating adhesive, or It can be performed by an extrusion lamination method in which lamination is performed via a melt-extruded resin layer made of a melt-extruded adhesive resin.
In the above, as the laminating adhesive, for example, one-part or two-part curable or non-cured vinyl type, (meth) acrylic type, polyamide type, polyester type, polyether type, polyurethane type, epoxy type, etc. It is possible to use an adhesive for laminating such as a solvent type such as rubber, others, an aqueous type, or an emulsion type.
As a coating method of the laminating adhesive, for example, direct gravure roll coating method, gravure roll coating method, kiss coating method, reverse roll coating method, fountain method, transfer roll coating method, and other methods can be used.
As the coating layer is preferably ^{0.1g / m 2 ~10g / m 2} ( dry state) position, more preferably ^{1g / m 2 ~5g / m 2} ( dry) position.
For example, an adhesion promoter such as a silane coupling agent can be arbitrarily added to the laminating adhesive.

In the above, as the melt-extrusion adhesive resin 8, the heat-sealable resin that forms the above-described heat-sealable resin layer can be used in the same manner. Specifically, for example, low-density polyethylene, especially linear It is preferable to use low density polyethylene, acid-modified polyethylene or polypropylene. The film thickness of the melt-extruded resin layer made of the above-described melt-extruded adhesive resin is preferably about 5 μm to 100 μm, more preferably about 10 μm to 50 μm.
In the present invention, when the above lamination is performed, if it is necessary to obtain a stronger adhesive strength, an adhesion improving agent such as an anchor coating agent can be coated. Examples of the anchor coating agent include organic titanium anchor coating agents such as alkyl titanates, isocyanate anchor coating agents, polyethyleneimine anchor coating agents, polybutadiene anchor coating agents, and other various aqueous or oil-based anchor coating agents. Can be used.
In the present invention, the anchor coating agent is coated by roll coating, gravure coating, knife coating, dip coating, spray coating, or other coating method, and the solvent, diluent, etc. are dried to form the anchor coating agent layer. can do.
The application amount of the anchor coating agent is preferably 0.1 g / m ^{2 to} 5 g / m ² (dry state).

Next, in the present invention, as the liquid paper container formed by using the laminate A for liquid paper containers according to the present invention and boxing it, for example, a liquid of a brick type, a flat type, a gobel top type, etc. Paper containers and the like can be manufactured. Moreover, the shape can manufacture any things, such as a rectangular container and a round cylindrical cylindrical paper can.
Furthermore, in the present invention, the liquid paper container according to the present invention is filled and packed with various articles such as various foods and drinks, chemicals such as adhesives and pressure-sensitive adhesives, cosmetics, miscellaneous goods such as pharmaceuticals, and the like. Is something that can be done.
In the present invention, the liquid paper container according to the present invention is particularly for packaging for filling and packaging liquid contents containing chemicals as content components such as alkaline contents, household detergents, car detergents, etc. It is a useful container with excellent chemical resistance, preservability of its contents, storage stability, and the like.

Next, the present invention will be described more specifically with reference to examples.
First, an aluminum foil having a thickness of 7 μm is used as a barrier layer, and a biaxially stretched polyethylene terephthalate film (hereinafter referred to as “PET film”) having a thickness of 12 μm is used as a pinhole-resistant layer. A laminated sheet was produced by laminating and laminating via an adhesive such that the dried adhesive layer was 3 μm by the dry lamination method. Subsequently, an anchor coating agent was coated on the PET film surface side of the laminated sheet at a coating amount (dry weight) of 0.5 g / m ² , and an unsaturated silane compound having a thickness of 40 μm was introduced as the innermost layer. A resin film containing a water-crosslinked product of an ethylene copolymer is interposed as an intervening resin layer with a melt-extruded resin made of polyethylene resin having a thickness of 20 μm, to form a layer structure, aluminum foil (7 μm) / adhesive layer / PET film ( 12 μm) / adhesive layer / polyethylene resin layer (20 μm) / a laminated sheet comprising a resin layer (40 μm) containing a water cross-linked product of an ethylene copolymer into which an unsaturated silane compound was introduced was prepared.
Next, using a urethane ink composition on the surface of a paperboard with a basis weight of 400 g / m ² as a paper base material layer, a printing pattern consisting of letters, symbols, patterns, figures, etc. is printed by gravure printing. The desired print was formed.
Next, the aluminum foil surface of the laminated sheet is subjected to in-line corona discharge treatment, and the surfaces on which the paper base material layer is not printed are overlapped to face each other, and a 20 μm thick intervening resin layer is interposed between the layers. A methacrylic acid / ethylene copolymer resin is extruded and laminated, and the barrier layer and the paper base material layer are bonded together to form a printed pattern layer / paper base material layer (400 g / m ² ) / methacrylic acid / ethylene copolymer. Resin layer (20 μm) / Aluminum foil (7 μm) / Adhesive layer / PET film (12 μm) / Adhesive layer / Polyethylene resin layer (20 μm) / Includes water-crosslinked product of ethylene copolymer with unsaturated silane compound introduced A laminated paper sheet consisting of a resin layer (40 μm) was produced.
Next, the printed surface of the laminated paper sheet is subjected to corona discharge treatment, and a 20 μm thick polyethylene resin is extruded and laminated as the outermost layer to obtain a polyethylene resin (20 μm) / printed pattern layer / paper substrate layer (400 g / m ² ) / methacrylic acid / ethylene copolymer resin layer (20 μm) / aluminum foil (7 μm) / adhesive layer / PET film (12 μm) / adhesive layer / polyethylene resin layer (20 μm) / unsaturated silane compound introduced A laminate composed of a resin layer (40 μm) containing a water cross-linked product of an ethylene copolymer was prepared.
Next, a brick-type paper container is formed using the obtained laminate, and after filling with an alkaline detergent as the contents, the inner surface of the top is scrubbed with hot air, the resin on the innermost layer side is melted, and the press sheet The package according to the present invention was manufactured.
The package manufactured above is packed with chemicals as content components such as alkaline content, household detergent, car detergent, etc., no delamination is observed, chemical resistance, storage stability of the content Storability, heat resistance, pinhole resistance, puncture resistance, heat sealability, anti-deformation strength, excellent barrier properties against light, oxygen gas, water vapor, etc., content filling suitability, and impact resistance It was a thing.

It is a schematic sectional drawing which shows the outline of the layer structure about the laminated body for liquid paper containers concerning this invention. It is a schematic perspective view which shows the structure of the liquid paper container in each box making process which shows the structure of the box making process about the box making of the liquid paper container concerning this invention using the laminated body shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outermost layer 2 Paper base material 3 Intervening resin layer 4 Intermediate layer 4a Barrier layer 4b Pinhole-resistant layer 5 Inner layer 6 Adhesive layer 7 for dry lamination Anchor coat layer 8 Melt extrusion adhesive resin layer 9 Print pattern layer 14 Shell seal part 15 Bottom seal part 17 Contents 18 Roof type top seal part A Laminate B for liquid paper container Sealed liquid paper container

Claims (1)

A laminate in which at least the outermost layer, the paper base layer, the intervening resin layer, the intermediate layer, and the innermost layer are sequentially laminated, and the intermediate layer constituting the laminate is at least a barrier layer, and / or An ethylene layer comprising a pinhole-resistant layer and laminated between the intermediate layer and the innermost layer via an adhesive resin layer, and the innermost layer is an ethylene in which an unsaturated silane compound is introduced. A liquid paper container comprising a resin layer containing a water cross-linked product of a copolymer, wherein the laminate is further used and boxed.

Images