JP2016112821A - Water-repellent laminate, and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems that when a content such as a food adheres to a packing material, the content remains in a packaging container to make it difficult to use completely, or in order to completely use the content, it takes time and labor to collect by scraping or squeezing the adhered content, and therefore, non-adhesiveness preventing the content from adhering is demanded for a packing material.SOLUTION: A water-repellent laminate 10 is characterized in that: at least a base material 1, a heat seal layer 2 and a water-repellent layer 3 are laminated in this order; the water-repellent layer 3 comprises a hydrophobic wax having a major component of at least one kind selected from polyethylene-based resin, polypropylene resin, paraffin, ethylene-acetic acid vinyl copolymer resin, and ethylene-acrylic acid copolymer; and a plurality of uneven structures are formed on the surface of the water-repellent layer 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a water-repellent laminate for use in packaging materials for foods, beverages, pharmaceuticals, chemicals, and the like, and more particularly to a water-repellent laminate excellent in non-adhesiveness of contents and its It relates to a manufacturing method.

  Conventionally, packaging materials corresponding to the contents have been developed for packaging use of many products such as foods, beverages, pharmaceuticals, and chemicals. Examples of the contents include yogurt, curry, mayonnaise, ketchup, liquid detergent, and the like, and the shapes of the contents are various, such as solid, semi-solid, liquid, viscous material, and gel.

  The packaging materials for packaging these contents are required to have hermeticity as well as thermal adhesiveness, light shielding, heat resistance, durability, etc. depending on the contents, packaging form, application, etc. The The packaging material for packaging the contents as described above has residual contents as another problem. When the contents adhere to the packaging material, the contents remain in the packaging container, making it difficult to use up all of the contents. Also, in order to use up all the contents, the attached contents must be scraped or squeezed out and collected, which is troublesome. Therefore, the packaging material is required to have non-adhesiveness in which the contents are difficult to adhere in addition to the above-described sealing performance.

Patent Document 1 is a lid member made of a laminate having at least a base material layer and a thermal adhesive layer, wherein the thermal adhesive layer is laminated as an outermost layer on one surface of the lid member, and the thermal adhesive layer is A lid in which hydrophobic oxide fine particles having an average primary particle diameter of 3 to 100 nm are attached to the outermost surface not adjacent to another layer, and the hydrophobic oxide fine particles form a porous layer having a three-dimensional network structure The material is disclosed.
In Patent Document 2, in a lid member having at least a base material layer and a heat sealing layer, a large number of microprojections having a height of 100 μm or less are densely provided on the entire outer surface of the heat sealing layer. An anti-adhesion layer is formed on the outer surface, and the anti-adhesion layer is made of hydrophobic fine particles, and its adhesion amount is 0.05 g / m ² or more and slightly covers the top end surface of the microprojections at most. The content adhesion prevention cover material characterized by being set to below quantity is disclosed.

Japanese Patent No. 4348401 Japanese Patent No. 5444143

  However, in Patent Documents 1 and 2, a coating liquid in which hydrophobic oxide fine particles are dispersed on an adhesive layer is applied, and the strength of the interface between the coating liquid and the adhesive layer can be obtained. It is difficult to control the adhesion strength. For this reason, there exists a problem that microparticles | fine-particles mix in the contents, such as foodstuff, as a foreign material.

  It is an object of the present invention to provide a water-repellent laminate that has non-adhesiveness to contents such as food and does not cause the water-repellent layer to fall off and enter the contents, and a method for producing the same.

The invention according to claim 1 is a water repellent laminate in which at least a substrate, a heat seal layer and a water repellent layer are laminated in this order,
The water-repellent layer is made of a hydrophobic wax mainly composed of at least one selected from polyethylene resin, polypropylene resin, paraffin, ethylene-vinyl acetate copolymer resin and ethylene-acrylic acid copolymer resin, The water repellent laminate is characterized in that a plurality of uneven structures are formed on the surface of the water repellent layer.
In the invention according to claim 2, the convex part of the concavo-convex structure formed on the surface of the water repellent layer is one of a pyramid shape, a trapezoidal shape, a conical shape, a hemispherical shape, an ellipsoidal shape, or 2. The water repellent laminate according to claim 1, wherein the water repellent laminate has a combined shape, a pitch of unevenness of 500 nm to 20000 nm, and a height of unevenness of 500 nm to 20000 nm.
Invention of Claim 3 is a manufacturing method of the water-repellent laminated body of Claim 1 or 2, Comprising:
Providing the heat seal layer on the substrate, forming a concavo-convex structure using a stamper on the heat seal layer, and laminating the water repellent layer on the heat seal layer having the concavo-convex structure formed thereon. It is a manufacturing method of the water-repellent laminated body which has these.
According to a fourth aspect of the present invention, the heat seal layer comprises an acrylic resin, a polyester resin, a polyethylene resin, a vinyl acetate resin, a vinyl chloride-vinyl acetate copolymer resin, a modified olefin resin, a synthetic rubber, The repellency of claim 3, comprising a heat-sealable varnish mainly composed of at least one selected from vinyl chloride resin, ethylene-acrylic acid copolymer resin, urethane resin and imine resin. It is a manufacturing method of an aqueous laminated body.
Invention of Claim 5 is a manufacturing method of the water-repellent laminated body of Claim 1 or 2, Comprising:
A water repellent laminate comprising a step of providing a heat seal layer having the plurality of concavo-convex structures on the substrate using a gravure roll, and a step of laminating the water repellent layer on the heat seal layer having the concavo-convex structure formed thereon. It is a manufacturing method of a body.
According to a sixth aspect of the present invention, the heat seal layer comprises at least one selected from an ethylene-vinyl acetate copolymer resin, a polyolefin resin, a polyamide resin, a synthetic rubber, an acrylic resin, and a polyurethane resin. The method for producing a water-repellent laminate according to claim 5, comprising a hot melt adhesive.
Invention of Claim 7 is a manufacturing method of the water-repellent laminated body of Claim 1 or 2, Comprising:
Water repellency comprising the steps of: providing the heat seal layer on the substrate; laminating the water repellent layer on the heat seal layer; and forming a concavo-convex structure on the water repellent layer using a stamper. It is a manufacturing method of a laminated body.

  In the water-repellent laminate according to the present invention, a water-repellent layer is formed on a heat seal layer having a concavo-convex structure, or a water-repellent layer is formed on the heat seal layer, and then a concavo-convex structure is formed on the water-repellent layer. Therefore, a water repellent layer including an air layer can be formed. For this reason, sufficient liquid repellency is shown with respect to the contents. In addition, the water-repellent layer having a concavo-convex structure has a strong cohesive force in the layer and does not fall off and be mixed into the contents.

It is a schematic diagram of the cross-sectional structure of the water-repellent laminate in the present invention.

FIG. 1 is a schematic view of a cross-sectional structure of a water-repellent laminate in the present invention.
The water-repellent laminate 10 in the present invention is formed by laminating at least a base material 1, a heat seal layer 2, and a water-repellent layer 3 in this order. When the water-repellent laminate 10 in the present invention is used as a packaging material, the water-repellent layer 3 constitutes the innermost layer in contact with the contents, and the water-repellent layer 3 plays a role of preventing the contents from adhering. .

  As the base material 1, paper, plastic film, aluminum foil, aluminum vapor deposition film, inorganic oxide vapor deposition film, and the like, and those obtained by appropriately combining these can be used.

  The surface of the substrate 1 may be printed with a product. The material, thickness, configuration and the like of the substrate 1 are appropriately selected depending on the required quality and workability of the target laminate.

A known material can be used for the heat seal layer 2. For example, it can be composed of a heat-sealable varnish or a hot-melt adhesive. Examples of the heat-sealable varnish include acrylic resins, polyester resins, polyethylene resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer Examples include heat-sealable varnish mainly composed of at least one selected from coalescing resin, modified olefinic resin, synthetic rubber, vinyl chloride resin, ethylene-acrylic acid copolymer resin, urethane resin and imine resin. It is done. Examples of the hot melt adhesive include a hot melt adhesive containing at least one selected from ethylene-vinyl acetate copolymer resin, polyolefin resin, polyamide resin, synthetic rubber, acrylic resin, and polyurethane resin. It is done. In addition, you may mix | blend a well-known wax, a tack fire, etc. with a hot-melt-adhesive.
The material, thickness, configuration, and the like of the heat seal layer 2 are appropriately selected depending on the required quality and workability of the target laminate, and for example, the thickness is preferably 5 to 50 μm.

As the water repellent layer 3, a hydrophobic wax mainly composed of at least one selected from polyethylene resin, polypropylene resin, paraffin, ethylene-vinyl acetate copolymer resin and ethylene-acrylic acid copolymer resin is used. used.
The material, thickness, configuration, and the like of the water repellent layer 3 are appropriately selected depending on the required quality and workability of the target laminate. For example, the thickness is preferably 0.5 to 10 μm.

The water-repellent laminate of the present invention has a plurality of concavo-convex structures formed on the surface. The shape of the convex portion of the concavo-convex structure is arbitrary such as a pyramid shape, a trapezoidal shape, a conical shape, a hemispherical shape, and an ellipsoidal shape.
The uneven pitch in the uneven structure is preferably 500 nm or more and 20000 nm or less, and the height of the unevenness is preferably 500 nm or more and 20000 nm or less. Here, the uneven pitch refers to the distance between the apexes of the convex portions or the distance between the central portions of the convex portions, and the height of the uneven portions refers to the distance between the apexes of the convex portions and the bottom of the concave portions.

  If the pitch of the unevenness is less than 500 nm or exceeds 20000 nm, the effect of the uneven structure is reduced, and the contents tend to adhere to the surface of the water-repellent layer 3. When the height of the unevenness is lower than 500 nm, the effect of dropping the liquid drops. On the other hand, if the height of the unevenness exceeds 20000 nm, the content tends to stagnate at the bottom of the recess, and the fallability becomes worse. The uneven pitch is more preferably 1000 nm to 10000 nm, and the uneven height is more preferably 1000 nm to 10000 nm.

Examples of a method for forming a concavo-convex structure in the water repellent layer 3 include the following methods (1) to (3).
First, (1) a heat seal layer 2 is provided on a base material 1, a concavo-convex structure having a desired shape is formed on the heat seal layer 2 using a stamper, and the repellency is formed on the heat seal layer 2 formed with the concavo-convex structure. There is a method of laminating the water layer 3.
(2) A method of providing a heat seal layer 2 having a concavo-convex structure of a desired shape on a substrate 1 using a gravure roll, and laminating a water repellent layer 3 on the heat seal layer 2 formed with the concavo-convex structure. There is.
(3) There is a method in which a heat seal layer 2 is provided on the base material 1 and a water repellent layer 3 is laminated on the heat seal layer 2 and then a concavo-convex structure is formed on the water repellent layer 3 using a stamper. . This method may cause some unevenness in the concavo-convex structure, but does not impair the effects of the present invention.
The heat seal layer 2 and the water repellent layer 3 can be formed on the base by employing a known coating method such as a gravure coating method, a die coating method, a dipping coating method, or a spray coating method.
Also, the formation of the concavo-convex structure by a stamper or gravure roll can be performed by appropriately adopting known means.

  EXAMPLES Hereinafter, although an Example and a comparative example further demonstrate this invention, this invention is not limited to the following example at all.

Example 1
A 12 μm polyethylene terephthalate film and 15 μm aluminum foil as a base material are laminated together by dry lamination using a urethane-based adhesive, and the same adhesive is used on the surface of the aluminum foil. What stuck the polyethylene terephthalate film was used. On this base material, the heat-sealable varnish which has a polyacrylate resin as a main component was apply | coated with the bar coat, and the 10-micrometer-thick heat seal layer was formed. Thereafter, a trapezoidal lattice-shaped uneven structure with an uneven pitch of 5000 nm and an uneven height of 5000 nm was formed on the heat seal layer by a stamper.

Next, a water-repellent coating solution in which paraffin wax (AQUACER 539 manufactured by BYK) is dispersed in a solvent of isopropyl alcohol: water = 1: 1 so as to be 10% by mass of the active ingredient is prepared and applied with a bar coat. A water-repellent layer having a coating amount of 1.0 g / m ² after drying was formed to prepare a desired water-repellent laminate.

(Example 2)
A water-repellent laminate was produced in the same manner as in Example 1 except that the stamper had a trapezoidal lattice-shaped uneven structure with a pitch of 10,000 nm and a height of 10,000 nm.

(Example 3)
A 12 μm polyethylene terephthalate film and 15 μm aluminum foil as a base material are laminated together by dry lamination using a urethane adhesive, and a polyethylene film is extruded and laminated on the surface of the aluminum foil using the same adhesive as described above. What was pasted together was used. On this base material, the hot-melt adhesive which has ethylene-vinyl acetate copolymer resin as a main component was hot-melt-coated using the gravure roll, and the 20-micrometer-thick heat seal layer was formed. This gravure roll had an uneven shape corresponding to an uneven pitch of 20000 nm and an uneven height of 20000 nm, and the uneven shape was transferred to the heat seal layer. Otherwise, the water-repellent laminate was produced in the same manner as in Example 1.

Example 4
In Example 1, after forming a heat seal layer without performing pressing with a stamper, a water repellent layer having a coating amount of 1.0 g / m ² after drying was formed on the heat seal layer. Next, a trapezoidal lattice-shaped concavo-convex structure having a pitch of 5000 nm and a height of 5000 nm was formed on the water-repellent layer using a stamper, and a desired water-repellent laminate was produced.

(Comparative Example 1)
In Example 1, a water-repellent laminate was produced in the same manner as in Example 1 except that the stamper was not used.

(Example 5)
A water-repellent laminate was produced in the same manner as in Example 1 except that the stamper had a trapezoidal lattice-shaped uneven structure with a pitch of 300 nm and a height of 300 nm.

(Example 6)
A water-repellent laminate was produced in the same manner as in Example 1 except that the stamper had a trapezoidal lattice-shaped uneven structure with a pitch of 50000 nm and a height of 50000 nm.

(Evaluation)
Using the water-repellent laminates produced in Examples 1 to 6 and Comparative Example 1, contact angle measurement and content adhesion test were performed. The measurement conditions are as follows.
Contact angle: The contact angle of pure water was measured using the water-repellent layer surface of the water-repellent laminate as a test surface.
Evaluation of content adhesion: When the water-repellent layer surface of the water-repellent laminate was used as a test surface and pasted on a slide glass, 0.5 g of water and yogurt were dropped in a horizontal state, and the slide glass was tilted at 90 degrees. The adhesion state of the contents of was evaluated. Judgment of the adhesion state was evaluated as “◯” when there was no adhesion on the test surface, “Δ” when partially adhered, and “×” when almost adhered to the entire surface.
Sealability evaluation: The sealability evaluation was performed as follows under the conditions of a temperature of 200 ° C., a pressure of 0.2 MPa, and a time of 3.0 seconds. Seal strength was measured with Tensilon. The sealability was evaluated as “good” when no water repellent layer was provided, and “poor” when the strength was 30% or more.
The results are shown in Table 1.

  As is clear from the results in Table 1, it can be seen that the non-adhesive property cannot be obtained with the water-repellent laminate of Comparative Example 1, but sufficient non-adhesive properties can be obtained with Examples 1 to 6.

DESCRIPTION OF SYMBOLS 1 Base material 2 Heat seal layer 3 Water repellent layer 10 Water repellent laminated body

Claims (7)

In a water-repellent laminate formed by laminating at least a base material, a heat seal layer and a water-repellent layer in this order,
The water-repellent layer is made of a hydrophobic wax mainly composed of at least one selected from polyethylene resin, polypropylene resin, paraffin, ethylene-vinyl acetate copolymer resin and ethylene-acrylic acid copolymer resin, A water repellent laminate having a plurality of uneven structures formed on a surface of the water repellent layer.   The convex portion of the concavo-convex structure formed on the surface of the water repellent layer has a pyramid shape, a trapezoidal shape, a conical shape, a hemispherical shape, an ellipsoidal shape, or a combination thereof, and has a concavo-convex shape. The water repellent laminate according to claim 1, wherein the pitch is 500 nm or more and 20000 nm or less, and the height of the unevenness is 500 nm or more and 20000 nm or less. A method for producing a water-repellent laminate according to claim 1 or 2,
Providing the heat seal layer on the substrate, forming a concavo-convex structure using a stamper on the heat seal layer, and laminating the water repellent layer on the heat seal layer having the concavo-convex structure formed thereon. A method for producing a water-repellent laminate comprising:   The heat seal layer is made of acrylic resin, polyester resin, polyethylene resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, modified olefin resin, synthetic rubber, vinyl chloride resin, ethylene-acrylic acid. The method for producing a water-repellent laminate according to claim 3, comprising a heat-sealable varnish mainly comprising at least one selected from a copolymer resin, a urethane-based resin, and an imine-based resin. A method for producing a water-repellent laminate according to claim 1 or 2,
A water repellent laminate comprising a step of providing a heat seal layer having the plurality of concavo-convex structures on the substrate using a gravure roll, and a step of laminating the water repellent layer on the heat seal layer having the concavo-convex structure formed thereon. Body manufacturing method.   The heat seal layer is made of a hot melt adhesive containing at least one selected from ethylene-vinyl acetate copolymer resin, polyolefin resin, polyamide resin, synthetic rubber, acrylic resin, and polyurethane resin. The method for producing a water-repellent laminate according to claim 5. A method for producing a water-repellent laminate according to claim 1 or 2,
Water repellency comprising the steps of: providing the heat seal layer on the substrate; laminating the water repellent layer on the heat seal layer; and forming a concavo-convex structure on the water repellent layer using a stamper. A manufacturing method of a layered product.

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