JP2013018533A - Water-shedding packaging material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-shedding packaging material preventing an adhesive content such as liquid, semisolid and a gel material from adhering and remaining on an inner face of the packaging material and having excellent heat seal performance.SOLUTION: In the water-shedding packaging material, a heat seal resin composition layer at least constituted of hydrophobic particles, a silane coupling agent and a thermoplastic resin is arranged on one face of a base material. The silane coupling agent includes at least one of an epoxy group, a vinyl group, a methacryloxy group and a mercapto group as a reactive functional group, and a blending quantity of the silane coupling agent is 0.01-10 mass% relative to a blending quantity of the hydrophobic particles.

Description

  The present invention relates to a material for packaging foods, beverages, pharmaceuticals, chemicals, and the like, and particularly to a water-repellent packaging material for contents having a viscous body such as a liquid, a semi-solid, or a gel substance.

  Conventionally, packaging materials corresponding to respective contents have been developed for many products such as foods, beverages, pharmaceuticals, and chemicals. In particular, as a packaging material for contents having a viscous material such as a liquid, semi-solid, or gel substance, a plastic material having excellent water resistance, oil resistance, gas barrier properties, light weight, flexibility, design properties, etc. is used. Is functioning to protect the contents required for

  In addition, as a packaging material for contents having viscous bodies such as liquids, semi-solids, gel substances, etc., for the purpose of providing higher functionality, a plastic laminate in which a plurality of various plastic substrates are laminated, paper, metal There have been proposed foils, composite laminates with inorganic materials, and composites obtained by applying a functional composition to a plastic substrate.

  As one of the high functions described above, for example, there is an attempt to prevent the content having a viscous material such as a liquid, a semi-solid, or a gel substance from adhering to the inner surface of the packaging material, that is, remaining inside the packaging body. Specifically, it is used for container materials such as yogurt, jelly, and syrup, retort food packaging materials such as porridge and soup, and film materials for storage containers such as chemical and pharmaceutical liquids, semi-solids, and gel substances. This is a method for solving the problem of substantial loss that cannot be removed due to the adhesion of contents and the contamination due to the adhesion of contents.

  With respect to these problems, for example, in Patent Document 1, hydrophobic oxide fine particles are attached to the outermost layer of the base material layer via a thermal adhesive layer, and most of the hydrophobic oxide fine particles are aggregates. Further, a packaging material having a porous layer having a three-dimensional network structure has been proposed.

  Further, in Patent Document 2, a heat-sealing lid material in which a heat-sealing layer and a content adhesion preventing layer are sequentially laminated on a base material, the content adhesion preventing layer being formed from wax and a filler dispersed in wax. In other words, it is a proposal that the filler is made of inorganic powder, organic powder, powder water-repellent resin, or the like.

  However, the proposal described in Patent Document 1 is a method of applying a coating liquid in which hydrophobic oxide fine particles are dispersed on an adhesive layer, and the strength of the interface between the adhesive layer and the coating liquid can be obtained. There is a problem that it is difficult to control the adhesion strength between physical particles. Further, the proposal described in Patent Document 2 has a problem that it is difficult to control the adhesion between the wax and the filler dispersed in the wax, that is, the cohesive force of the content adhesion preventing layer. Therefore, each proposal has a problem in achieving both adhesion strength with the base material and prevention of adhesion of contents.

Patent No. 4348401 JP 2009-73523 A

  The object of the present invention is that the content does not adhere to or remain on the inner surface of the packaging material with respect to the content having adhesive properties such as liquid, semi-solid and gel-like substances, and has excellent heat sealability. It is to provide a water repellent packaging material.

  In order to solve the above problems, the invention according to claim 1 of the present invention is provided with a heat seal resin composition layer comprising at least hydrophobic fine particles, a silane coupling agent, and a thermoplastic resin on one surface of a substrate. A water repellent packaging material, wherein the silane coupling agent has at least one of an epoxy group, a vinyl group, a methacryloxy group, and a mercapto group as a reactive functional group, and the amount of the silane coupling agent is It is a water-repellent packaging material characterized by being 0.01 to 10% by mass with respect to the blended amount of hydrophobic fine particles. That is, the reactive functional group of the silane coupling agent allows the silane coupling agent to bond between the thermoplastic resin having heat sealing properties and the hydrophobic fine particles, so that the substrate and the heat seal resin composition layer The effect of improving the adhesion strength is obtained. Furthermore, by setting the blending amount of the silane coupling agent to 0.01 to 10% by mass with respect to the blending amount of the hydrophobic fine particles, there is no extra silane coupling agent and optimal adhesion strength can be obtained. .

  Further, in the invention according to claim 2 of the present invention, the hydrophobic fine particles are silicone particles, inorganic oxides surface-treated with a functional group having a silyl ether bond or a siloxane bond, or a mixture thereof. The water-repellent packaging material according to claim 1, wherein the secondary particle diameter is 10 to 10,000 nm. That is, the surface of the inorganic oxide or a mixture thereof is surface-treated with a functional group having a silyl ether bond or a siloxane bond, thereby increasing the affinity with the thermoplastic resin in the heat seal resin composition. Subsequent aggregation is prevented and stable water repellency is obtained.

  In the invention according to claim 3 of the present invention, the heat seal resin composition layer contains a silicone resin, and the content thereof is 0.01 to 10% by mass with respect to the content of the thermoplastic resin. The water repellent packaging material according to claim 1 or 2, wherein the water repellent packaging material is provided. That is, by making the content of the silicone resin 0.01 to 10% by mass with respect to the content of the thermoplastic resin, the effect of improving the water repellency of the thermoplastic resin itself due to the low surface tension of the silicone resin. can get.

  The invention according to claim 4 of the present invention is the water-repellent packaging material according to claim 3, wherein the silicone resin has a methacryloxy group as a reactive functional group at least at a terminal. That is, the reactive functional group reacts with the thermoplastic resin, resulting in a strong adhesion.

  According to the present invention, the content does not adhere to or remain on the inner surface of the packaging material with respect to the content having adhesive properties such as liquid, semi-solid and gel-like substances, and has excellent heat sealability. A water repellent packaging material can be provided.

It is a cross-sectional schematic diagram of one Embodiment of the water-repellent packaging material of this invention.

  The present invention will be described below with reference to the drawings. FIG. 1: shows the cross-sectional schematic diagram of one Embodiment of the water-repellent packaging material of this invention. As shown in FIG. 1, in the present invention, a primer layer 2 is provided on one side of a substrate 1 as necessary, and a heat seal resin composition layer comprising hydrophobic fine particles, a silane coupling agent, and a thermoplastic resin thereon. 3 is a water-repellent packaging material 10.

As the base material 1 according to the present invention, a plastic film alone, a laminate of different plastic films, a composite laminate of a plastic film and paper, metal foil, or an inorganic material can be used.

  The heat seal resin composition layer 3 according to the present invention is formed by applying and drying a heat seal resin composition comprising at least hydrophobic fine particles, a silane coupling agent, a thermoplastic resin, and a solvent. is there.

  As the hydrophobic fine particles, silicone particles, inorganic oxides surface-treated with a functional group having a silyl ether bond or a siloxane bond, or a mixture thereof can be used. Examples of the functional group having a silyl ether bond or a siloxane bond include dimethylsilyl, trimethylsilyl, dimethylpolysiloxane, dimethylsiloxane, aminoalkylsilyl, alkylsilyl, and methacrylsilyl.

The silicone particles are preferably methylsilicones such as polymethylsilsesquioxane and polyorganosilsesquioxane having a (RSiO _3/2 ) structure in which siloxane bonds are three-dimensionally bonded.

  In addition, the hydrophobic fine particles may be silicone particles or surface-treated inorganic oxides alone, but when used in combination, the secondary particle diameter distribution range is widened, and the fine irregular surface is further reduced to the fine irregular surface. As a result, a fractal structure can be formed in a pseudo manner, and as a result, a water repellent effect can be easily obtained. Moreover, the secondary particle diameter for obtaining such an effect is preferably 10 to 10,000 nm, and can be obtained by a kneading step using a stirrer, a ball mill, an ultrasonic wave, or the like when the heat seal resin composition is produced.

  The silane coupling agent has an effect of improving the adhesion between the hydrophobic fine particles in the heat seal resin composition and the thermoplastic resin and improving the hydrophobicity of the heat seal resin composition layer, and has an epoxy as a reactive functional group. It preferably has at least one of a group, a vinyl group, a methacryloxy group, and a mercapto group. More preferably, 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- Methacryloxypropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane, and the addition amount is preferably 0.01 to 10% by mass with respect to the hydrophobic fine particles. When the addition amount of the silane coupling agent to the hydrophobic fine particles is less than 0.01% by mass, the number of bonding hands is small, and the adhesion is weakened. Moreover, when it exceeds 10 mass%, an excess silane coupling agent will inhibit adhesiveness.

  The said thermoplastic resin is suitably selected by the base material which provides a heat seal resin composition layer. For example, when the base material is polyethylene resin, ethylene-vinyl acetate copolymer (EVA) resin or polyethylene (PE) resin, and when the base material is polypropylene (PP) resin, EVA resin, PE resin or modified olefin resin When the base material is polystyrene resin, acrylic resin, EVA resin, vinyl chloride-vinyl acetate copolymer (vinyl acetate resin), PE resin, styrene-butadiene rubber (SBR resin), polyester resin, etc. are used. It is done.

  In order to increase the hydrophobicity of the matrix resin itself of the heat seal resin composition, it is preferable to add a silicone resin to the thermoplastic resin. In this case, the silicone resin is preferably a modified silicone having a methacryloxy group as a reactive functional group at least at the terminal, and the addition amount is preferably 0.01 to 10% by mass with respect to the thermoplastic resin. When the addition amount of the silicone resin is less than 0.01% by mass, it cannot contribute to the reduction of the surface tension of the matrix.

  Moreover, it does not specifically limit as a coating method of the heat seal resin composition which concerns on this invention, A general gravure coat method, a roll coat method, etc. can be utilized.

  Hereinafter, the present invention will be described specifically by way of examples.

<Example 1>
On the PET surface of a base material in which a 7 μm thick aluminum foil and a 16 μm thick polyethylene terephthalate (PET) film are sequentially laminated on one side of a simulated paper having a basis weight of 52.3 g / m ² through an adhesive, The following primer and heat seal resin composition were sequentially applied to prepare a water-repellent packaging material.
<Primer> (Application amount after drying: 1 g / m ² )
Polyester resin (Mitsui Chemicals, trade name “A3210”) 15 parts by weight Isocyanate curing agent (Mitsui Chemicals, trade name “A3075”) 5 parts by weight Solvent (ethyl acetate) 205 parts by weight <Heat seal resin composition> (Application amount after drying: 3 g / m ² )
Acrylic resin 5 parts by mass Solvent: ethanol 90 parts by mass Silane coupling agent (A): 0.005 parts by mass 3-Methacryloxypropyltrimethoxysilane (trade name “A-174” manufactured by MOMENTIVE)
Hydrophobic fine particles (B): 5 parts by mass of methyl silicone (manufactured by Nikko Rica, trade name “MSP-S110”)
Silane coupling agent (A) / hydrophobic fine particles (B) 0.1% by mass

<Example 2>
A water-repellent packaging material was produced in the same manner as in Example 1 except that the heat seal resin composition was changed to the following composition.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
Acrylic resin 5 parts by mass Solvent: ethanol 90 parts by mass Silane coupling agent (A): 0.05 part by mass 3-Methacryloxypropyltrimethoxysilane (trade name “A-174” manufactured by MOMENTIVE)
Hydrophobic fine particles (B): 5 parts by mass of methyl silicone (manufactured by Nikko Rica, trade name “MSP-S110”)
Silane coupling agent (A) / hydrophobic fine particles (B) 1.0 mass%

<Example 3>
A water-repellent packaging material was produced in the same manner as in Example 1 except that the heat seal resin composition was changed to the following composition.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
Acrylic resin 5 parts by mass Solvent: Ethanol 90 parts by mass Silane coupling agent (A): 0.25 part by mass 3-Methacryloxypropyltrimethoxysilane (manufactured by MOMENTIVE, trade name “A-174”)
Hydrophobic fine particles (B): 5 parts by mass of methyl silicone (manufactured by Nikko Rica, trade name “MSP-S110”)
Silane coupling agent (A) / hydrophobic fine particles (B) 5.0 mass%

<Example 4>
A water-repellent packaging material was prepared in the same manner as in Example 2 except that the silane coupling agent (A) was changed to 3-glycidoxypropyltrimethoxysilane (trade name “A-187” manufactured by MOMENTIVE). .

<Example 5>
A water-repellent packaging material was prepared in the same manner as in Example 2 except that the silane coupling agent (A) was changed to vinyltrimethoxysilane (trade name “A-151NTJ” manufactured by MOMENTIVE).

<Example 6>
A water-repellent packaging material was produced in the same manner as in Example 2, except that the silane coupling agent (A) was changed to 3-mercaptopropyltrimethoxysilane (manufactured by MOMENTIVE, trade name “A-189”).

<Example 7>
The silane coupling agent (A) is 3-methacryloxypropyltrimethoxysilane (trade name “A-174” manufactured by MOMENTIVE), and the hydrophobic fine particles (B) are trimethylsilyl SiO ₂ (trade name “RX200” manufactured by Nippon Aerosil Co., Ltd.). A water-repellent packaging material was produced in the same manner as in Example 2 except that “)” was changed.

<Example 8>
A water-repellent packaging material was prepared in the same manner as in Example 2 except that the solvent of the heat seal resin composition (A) was MEK (methyl ethyl ketone).

<Example 9>
A water-repellent packaging material was produced in the same manner as in Example 2 except that the resin of the heat seal resin composition (A) was EVA and the solvent was MEK.

<Example 10>
A water-repellent packaging material was produced in the same manner as in Example 2 except that the resin of the heat seal resin composition (A) was PE and the solvent was MEK.

<Example 11>
A water-repellent packaging material was produced in the same manner as in Example 2 except that the resin of the heat seal resin composition (A) was PP and the solvent was MEK.

<Example 12>
A water-repellent packaging material was prepared in the same manner as in Example 2 except that the resin of the heat seal resin composition (A) was vinyl acetate and the solvent was MEK.

<Example 13>
A water-repellent packaging material was produced in the same manner as in Example 2 except that the resin of the heat seal resin composition (A) was SBR and the solvent was MEK.

<Example 14>
A water-repellent packaging material was produced in the same manner as in Example 2 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
Acrylic resin 5 parts by weight Silicone resin (reactive functional group: methacryloxy group) 0.05 part by weight Solvent: MEK 90 parts by weight Silane coupling agent (A): 0.005 parts by weight 3-methacryloxypropyltrimethoxysilane (MOMENTIVE Product name “A-174”)
Hydrophobic fine particles (B): 5 parts by mass of methyl silicone (manufactured by Nikko Rica, trade name “MSP-S110”)
Silane coupling agent (A) / hydrophobic fine particles (B) 1.0 mass%
Silicone resin / acrylic resin 1.0% by mass

<Comparative Example 1>
A water-repellent packaging material was prepared in the same manner as in Example 1 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
Acrylic resin 5 parts by mass Solvent: Ethanol 90 parts by mass

<Comparative example 2>
A water-repellent packaging material was prepared in the same manner as in Example 1 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
Acrylic resin 5 parts by mass Solvent: Ethanol 90 parts by mass Silane coupling agent (A): 0.75 part by mass 3-Methacryloxypropyltrimethoxysilane (product name “A-174” manufactured by MOMENTIVE)
Hydrophobic fine particles (B): 5 parts by mass of methyl silicone (manufactured by Nikko Rica, trade name “MSP-S110”)
Silane coupling agent (A) / hydrophobic fine particles (B) 15.0 mass%

<Comparative Example 3>
A water-repellent packaging material was prepared in the same manner as in Example 1 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
EVA resin 5 parts by mass Solvent: MEK 90 parts by mass

<Comparative example 4>
A water-repellent packaging material was prepared in the same manner as in Example 1 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
PE resin 5 parts by mass Solvent: 90 parts by mass of MEK

<Comparative Example 5>
A water-repellent packaging material was prepared in the same manner as in Example 1 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
PP resin 5 parts by weight Solvent: MEK 90 parts by weight

<Comparative Example 6>
A water-repellent packaging material was prepared in the same manner as in Example 1 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
Vinyl acetate resin 5 parts by mass Solvent: 90 parts by mass of MEK

<Comparative Example 7>
A water-repellent packaging material was prepared in the same manner as in Example 1 except that the following heat seal resin composition was used.
<Heat seal resin composition> (Application amount after drying: 3 g / m ² )
SBR resin 5 parts by mass Solvent: MEK 90 parts by mass

<Evaluation items and methods>
Using the water-repellent packaging materials prepared in Examples 1 to 14 and Comparative Examples 1 to 7, the falling angle and particle adhesion of the heat seal resin composition layer were evaluated. The results are shown in Table 1 below.
Falling angle-tap water was dropped onto the surface of the heat seal resin composition layer, the water-repellent packaging material was tilted with the dropping liquid placed thereon, and the angle at which the dropping liquid fell was measured as the falling angle.
Tumble angle: 10 ° or less ◎ 10 ° to 30 ° ○, 30 ° to 60 ° △, 60 ° or more ×
Determined.
-Particle adhesion-Adhesive tape was affixed to the surface of the heat seal resin composition layer, and then the adhesion state of the hydrophobic fine particles to the adhesive tape side when peeled was evaluated.
Particle adhesion: No particle adhesion was judged as ◯, and adhesion was judged as x.

<Comparison result>
The products of the present invention obtained in Examples 1 to 14 all showed good results with a sliding angle of 10 ° to 30 °. In addition, the adhesion of the hydrophobic fine particles did not adhere to the adhesive tape side, and good results were obtained. On the other hand, all of the comparative example products obtained in Comparative Examples 1 to 7 were inferior in water repellency with a sliding angle of 60 ° or more. In addition, all of the comparative example products also had a result that the hydrophobic fine particles adhered to the adhesive tape side in terms of adhesion. From the above, the product of the present invention has excellent water repellency and shows very good results with no decrease in seal strength.

DESCRIPTION OF SYMBOLS 1 Base material 2 Primer layer 3 Heat seal resin composition layer 10 Water-repellent packaging material

Claims (4)

  A water-repellent packaging material in which a heat seal resin composition layer comprising at least hydrophobic fine particles, a silane coupling agent and a thermoplastic resin is provided on one side of a substrate, wherein the silane coupling agent is an epoxy as a reactive functional group Having at least one of a group, a vinyl group, a methacryloxy group, and a mercapto group, and the blending amount of the silane coupling agent is 0.01 to 10% by mass with respect to the blending amount of the hydrophobic fine particles. Water repellent packaging material characterized by   The hydrophobic fine particle is a silicone particle, an inorganic oxide surface-treated with a functional group having a silyl ether bond or a siloxane bond, or a mixture thereof, and a secondary particle diameter of 10 to 10,000 nm. The water repellent packaging material according to claim 1.   The said heat seal resin composition layer contains a silicone resin, The content is 0.01-10 mass% with respect to content of the said thermoplastic resin, The Claim 1 or 2 characterized by the above-mentioned. Water repellent packaging material.   The water repellent packaging material according to claim 3, wherein the silicone resin has a methacryloxy group as a reactive functional group at least at a terminal.

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