JP2006056093A - Water-repellent flexible packaging material and packaging bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-repellent flexible packaging material which makes water adherent to its surface be removed easily and is remarkably lowered in adsorbency in relation to water etc., on the surface in order to solve the following problems: when, for example, after the contents are packed in the packaging material, refrigerated, and defrosted by being allowed to stand at room temperature, printing is applied on the surface of the packaging material, or a label is stuck on the surface, bedewing occurs on the surface, deteriorating aptitudes for printing and label sticking by the adsorption of water on the surface, and a packaging bag obtained by using the packaging material. <P>SOLUTION: The water-repellent flexible packaging material having at least a water-repellent layer on the surface of a substrate and the packaging bag obtained by using the packaging material are provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water-repellent soft packaging material in which a water-repellent layer having water repellency is formed on the surface, and the adsorptivity to the surface of water or the like is remarkably lowered, and a packaging bag using the packaging material.

  2. Description of the Related Art Conventionally, in soft packaging materials that use polymer films, paper, and the like as raw materials, the packaging materials are filled and stored with contents, and then refrigerated and frozen on a daily basis. However, after refrigeration and freezing, it may be left at room temperature and thawed before printing or labeling on the surface of the packaging material. In such a case, condensation occurs on the surface of the packaging material, and the packaging material The moisture adsorbed on the surface of the surface deteriorates the suitability for printing and labeling, and often causes problems in printing and labeling.

  As a preventive measure, the work of carefully wiping off the condensed moisture generated on the surface of the packaging material was performed, but the work efficiency was poor and the moisture adsorbed on the surface of the packaging material could not be removed. There was a problem in printing and labeling. In addition, the dew moisture generated on the surface of the packaging material has been subjected to a drying process with a drier or the like, but the drying process takes a long time and has a problem in work efficiency.

  The present invention has been made in order to solve the above-described problems, and the water-repellent soft packaging material has good drainage of water adhering to the surface of the packaging material, and has significantly reduced the adsorptivity to water on the surface. Another object of the present invention is to provide a packaging bag using the packaging material.

In order to solve the above problems,
The invention according to claim 1
It is a water-repellent soft packaging material characterized by having a water-repellent layer at least on the surface of a substrate.

The invention according to claim 2
The water repellent soft packaging material according to claim 1, wherein a sealant layer is laminated on the surface of the base material opposite to the water repellent layer.

The invention according to claim 3
The water-repellent soft packaging material according to claim 1 or 2, wherein the water-repellent layer has a surface wetness index of 35 mN / m or more and 41 mN / m or less.

The invention according to claim 4
It is the packaging bag produced using the flexible packaging material of any one of Claims 1-3.

  According to the present invention, a water-repellent soft wrapping material having a water-repellent layer formed on the surface thereof, having good water drainage of the water adhering to the surface, and having significantly reduced the adsorptivity to water on the surface and the soft wrapping material It became possible to provide a packaging bag using

When the water-repellent soft packaging material and packaging bag of the present invention are filled with contents, stored, then refrigerated, frozen at room temperature and then thawed before printing or labeling on the surface of the packaging material Even so, the moisture condensed on the surface of the packaging material is simply wiped off, so that no moisture is adsorbed on the surface, and there is no problem in printing or labeling. In addition, since there is no need for a drying process for removing moisture adsorbed on the surface of the packaging material, work efficiency is improved.

  A preferred embodiment of the water-repellent soft packaging material of the present invention will be described below. FIG. 1 is a schematic cross-sectional view showing an example of the water-repellent soft packaging material of the present invention. As shown in FIG. 1, a water-repellent flexible packaging material 10 as an embodiment of the present invention forms a water-repellent water-repellent layer 3 on the surface of a soft packaging material substrate 1, and the water-repellent layer 3 The sealant layer 2 is laminated on the surface of the substrate 1 on the opposite side via the adhesive layer 4.

  As the base material 1 constituting the flexible packaging material used in the present invention, a single-layer resin film can also be used, but in general, a paper, an aluminum foil, a gas barrier resin film, etc. can be laminated on the resin film. A base material made of a laminate having flexibility is used.

  Examples of the resin film include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polybutylene naphthalate, and other polyesters, ethylene-propylene copolymers, etc. Examples thereof include a resin film having a heat fusion property.

  Further, a resin film such as polyvinylidene chloride having a barrier property against oxygen, water vapor, etc., polyvinyl alcohol, saponified ethylene-vinyl acetate copolymer, and the like can also be used.

The substrate resin film may be subjected to surface treatment such as corona treatment, flame treatment, plasma treatment, glow discharge treatment, roughening treatment, chemical treatment, etc. before lamination or before forming a water repellent layer. You may go. ,
The water repellent layer 3 formed in the present invention is not particularly limited as long as it is a layer formed on the surface of the soft packaging material and having water repellency. By having water repellency, water drainage is good, and the adsorptivity to water on the surface can be remarkably reduced. The water repellent layer 3 used in the present invention has a water repellency with a surface wettability index of 35 mN / m or more and 41 mN / m or less, more preferably 36 mN / m or more and 39 mN / m or less. It is preferable. With such a surface wetting index, it is possible to prevent moisture and the like from being adsorbed on the surface. In addition, even if printing is performed on the surface of a packaging material or a packaging bag after thawing by refrigeration and freezing at room temperature, printing and labeling suitability are not impaired.

  Such a water-repellent layer 3 may be formed by any method as long as it is a layer having water repellency as described above. Specifically, it may be formed by a plasma CVD method (plasma polymerization method) or a vapor deposition method using a PVD method, or for forming a water repellent layer in which a water repellent layer forming material is dissolved or suspended in a solvent. It may be formed by applying a coating liquid.

  On the other hand, in consideration of the point that conventional water repellent material can be used as it is and the point that it can be used even if it is a material that cannot be applied to the vapor deposition method, the water repellent layer forming coating liquid as described above is applied. It is preferable that the water-repellent layer is formed by the method described above.

The substance constituting the water repellent layer 3 is greatly different depending on the method for forming the water repellent layer as described above. Specifically, the material constituting the water-repellent layer when the water-repellent layer is formed by vapor deposition is composed of an organic film having a metal skeleton and having a methyl group, carbon and hydrogen (C and H) only. An organic film and a film containing fluorine (F) can be given.

  In addition, examples of the material constituting the water repellent layer in the case of applying the water repellent layer forming coating liquid as described above include silicon-based organic materials and fluorine-based organic materials.

  A suitable film thickness in such a water-repellent layer 3 varies greatly depending on the manufacturing method. Specifically, the preferred film thickness when the water repellent layer is formed by vapor deposition is preferably in the range of 1 nm to 1000 nm, particularly in the range of 5 nm to 100 nm. On the other hand, the preferred film thickness in other methods, that is, a method other than the vapor deposition method such as a method of forming by applying a coating liquid for forming a water repellent layer or a method of melting and applying a thermoplastic resin is 10 nm to It is preferably in the range of 50 μm, particularly preferably in the range of 50 nm to 300 nm.

  If the film thickness 3 of the water repellent layer is thinner than the above range, it is not preferable because the function as the water repellent layer may not be exhibited, for example, a portion where the water repellent layer is not formed may occur. Even if the thickness is increased, it does not affect the water repellency, which may cause a problem in terms of cost.

  The sealant layer 2 used in the present invention is used as a heat seal adhesive layer when used as a packaging bag or the like, and examples of the heat seal resin include resins that can be melted by heat and fused to each other. Can do. Specifically, low density polyethylene, medium density polyethylene, high density polyethylene, linear (linear) low density polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene -Methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, polyolefin resin such as polyethylene or polypropylene, acrylic acid, methacrylic acid, maleic acid, maleic anhydride An acid-modified polyolefin resin modified with an unsaturated carboxylic acid such as acid, fumaric acid or itaconic acid, a polyvinyl acetate resin, a poly (meth) acrylic resin, a polyvinyl chloride resin or the like can be used. The heat-sealable resin layer 13 may be formed by applying the heat-sealable resin as described above, or may be formed by laminating a film or sheet made of the heat-sealable resin as described above. . The thickness of the heat-sealable resin layer 13 can be set within a range of 5 to 300 μm, preferably 10 to 100 μm.

  The adhesive used for the adhesive layer 4 and the bonding method in the present invention can be performed by a method of laminating a normal packaging material, and is not particularly limited. For example, a two-component curable urethane resin or the like can be used. A dry lamination method is preferable as a method of bonding using an adhesive.

  A packaging bag using the water-repellent soft packaging material of the present invention will be described. This packaging bag is made by heat-sealing using the water-repellent soft packaging material of the present invention having the above-described configuration.

  Specifically, in the case of a soft packaging bag, the surface of the sealant layer made of the heat-sealable resin of the water-repellent soft packaging material is folded so as to face each other, or the two sealants using the water-repellent soft packaging material of the present invention are used. Layer surfaces are overlapped, and the peripheral edge is, for example, side seal type, two-side seal type, three-side seal type, four-side seal type, envelope-attached seal type, joint-attached seal type (pillow seal type), pleated seal Various forms of packaging bags according to the present invention can be manufactured by forming a seal portion by heat-sealing with a heat seal mode such as a mold, a flat bottom seal type, a square bottom seal type, or the like.

In the above, the heat fusion can be performed by a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, an ultrasonic seal, and the like.

  FIG. 2 is a perspective view showing an example of the packaging bag as described above. In FIG. 2, a packaging bag 20 is formed by stacking a pair of the laminated materials 10 of the present invention so that the sealant layer 2 made of the heat-sealable resin faces each other, and in this state, heat sealing is performed on three sides of the peripheral portion. Thus, the seal portion 21 is formed. The packaging bag 20 can be filled with contents from an opening 22 formed in the remaining one of the peripheral part. And after filling the content, the said opening part 22 is heat-seal | fused, and it can be set as the packaging bag which filled and packaged the content by forming a seal part.

  The packaging bags filled and packaged with the contents as described above are refrigerated and frozen on a daily basis. In some cases, after refrigeration and freezing, the product is left at room temperature and defrosted, and then the surface of the packaging material or the packaging bag is printed or labeled. In such a case, condensation occurs on the surface of the packaging material or the packaging bag, water droplets adhere to it, and there is a problem that the suitability for printing or labeling is impaired due to moisture adsorbing on the surface of the packaging bag. As described above, the above problem can be solved by forming the water repellent layer on the surface of the flexible packaging material.

  Specific examples of the present invention will be described below.

The water-repellent soft packaging material of the present invention having the configuration shown in FIG. 1 was prepared. Using a polyethylene terephthalate (PET) film having a thickness of 12 μm as the substrate 1, a water-repellent coating solution having the composition shown below was prepared and applied and dried on the surface of one side of the PET film. A water-repellent layer 3 of 1 g / m ² (dry state) was formed. Next, a linear low-density polyethylene having a thickness of 40 μm is formed as a sealant layer 2 on the PET film surface through the adhesive layer 4 by a dry lamination method using an adhesive made of a two-component curable polyurethane resin. The water-repellent soft packaging material of the present invention was prepared by bonding using a film. And when the surface-wetting index in the surface of said water-repellent layer 3 was measured based on the test method based on JISK6768, it was 37 mN / m.

<Adjustment of water-repellent coating solution>
Tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ] is added to 1N hydrochloric acid, stirred and hydrolyzed in a water / methanol solution, and water / tetraethoxysilane / 1N hydrochloric acid (dilute hydrochloric acid) / methanol = 120 by weight. A water repellent coating solution of /80/0.3/30 was prepared.

Thereafter, a sealant layer 2 made of a linear low-density polyethylene film of the water-repellent soft packaging material obtained above is used as the inside, and a 200 mm long and 100 mm wide three-side sealed bag is generally used with a known bag making machine. It was set as a packaging bag. The water repellent soft packaging bag was filled with about 60 ml of water, and the opening was sealed and heat sealed.

  The water-repellent soft packaging bag filled with the contents was stored at a temperature of 8 ° C. for 12 hours. Thereafter, the room temperature was returned to 20 ° C., and water droplets were observed on the surface of the packaging bag in about 5 minutes.

  Water droplets adhering to the surface of the packaging bag were wiped off, and a general commercially available label was attached to the surface using a generally known labeling machine, and then the label adhesive strength was measured. The measurement of the adhesive strength was performed under conditions of a width of 15 mm, T-type peeling, and a peeling speed of 300 mm / min. The results are shown in Table 1.

As a comparative example for comparing the performance of the water-repellent soft packaging material of the present invention, in Example 1, a soft packaging material was prepared in the same manner as in Example 1 except that the water-repellent layer was not formed on the surface of the soft packaging material. It was 42 mN / m when prepared and the surface wetting index was measured. Further, packaging bags were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.

  From Table 1, the surface wettability index of the surface water-repellent layer of the water-repellent soft packaging material of the present invention satisfies the range of 35 mN / m or more and 41 mN / m or less. After that, dew condensation occurs on the surface of the packaging material or packaging bag, it can be easily wiped off even if water droplets adhere to it, and furthermore, moisture does not adsorb on the surface of the packaging material or packaging bag, making it suitable for labeling Will not be damaged. Of course, when printing on the surface of a packaging material or a packaging bag, the printability is not impaired.

It is a cross-sectional schematic diagram which shows an example of a structure of the water-repellent soft packaging material of this invention. It is a model perspective view which shows an example of the packaging bag using the water-repellent soft packaging material of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material layer 2 ... Sealant layer 3 ... Water-repellent layer 4 ... Adhesive layer 10 ... Water-repellent soft packaging material 20 ... Packaging bag 21 ... Seal part 22- ··Aperture

Claims (4)

  A water-repellent soft packaging material having at least a water-repellent layer on a substrate surface.   The water repellent soft packaging material according to claim 1, wherein a sealant layer is laminated on the surface of the base material opposite to the water repellent layer.   The water-repellent soft packaging material according to claim 1 or 2, wherein the water-repellent layer has a surface wetness index of 35 mN / m or more and 41 mN / m or less.   A packaging bag produced using the flexible packaging material according to claim 1.

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