KR20220158164A - Composite film for vacuum insulation panel - Google Patents

Abstract

The present invention relates to a composite film for a vacuum insulation panel having excellent interlayer adhesion and gas barrier properties. The present invention includes: a base layer including a base film; a natural product blocking layer including a natural product hydrogel; a first adhesive layer provided on one surface of the natural product blocking layer; a second adhesive layer provided on the other surface of the base layer; a first blocking layer provided on one surface of the first adhesive layer; and a second blocking layer provided on one surface of the second adhesive layer.

Description

Composite film for vacuum insulation panel {COMPOSITE FILM FOR VACUUM INSULATION PANEL}

The present invention relates to a composite film for a vacuum insulation panel.

[R&D project supporting this invention]

[Assignment identification number] D202073

[Name of department] Gyeonggi-do

[Research management institution] Gyeonggi Economic Science Promotion Agency

[Research project name] Enterprise-led general

[Research Project Title] Development of eco-friendly film for vacuum insulation as an alternative to imported metal film

[Contribution rate] 1/1

[Organizer] Everchemtech Co., Ltd.

[Research Period] 2020.2.1 ~ 2021.5.31

Since the surroundings of the core material are maintained in a vacuum state by the outer covering material and the sealing material, the vacuum insulation panel has excellent thermal insulation performance due to very low thermal conductivity due to gas. In such a vacuum insulation panel, since the inside of the insulation panel must be continuously maintained in a vacuum in order to maintain its insulation performance, the gas barrier property of the outer covering material is important.

In the case of a conventional vacuum insulation panel, the shell material has been composed of a multi-layer film including a metal deposited film or aluminum foil. However, generally, in configurations using metal foil as a gas barrier layer, the amount of heat transferred through the metal foil is large, and there is a problem in that the heat insulating effect of the vacuum insulation panel is inhibited by a so-called heat bridge phenomenon.

In addition, since the covering material must withstand the force of vacuum pressure during the manufacture of the vacuum insulation panel, the multilayer film constituting the covering material needs to have sufficient interlayer adhesive strength and sealing strength.

Accordingly, it is necessary to develop a composite film for a vacuum insulation panel having excellent gas barrier properties and interlayer adhesive strength.

The present invention provides a composite film for a vacuum insulation panel having excellent interlayer adhesion and gas barrier properties.

However, the problem to be solved by the present invention is not limited to the above-mentioned problem, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

An exemplary embodiment of the present invention is a base layer comprising a base film; a natural blocking layer provided on one surface of the base layer and containing a natural hydrogel; a first adhesive layer provided on one surface of the natural product blocking layer; A second adhesive layer provided on the other surface of the substrate layer; a first blocking layer provided on one surface of the first adhesive layer; and a second blocking layer provided on one surface of the second adhesive layer.

The composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention may have excellent interlayer adhesion and gas barrier properties.

In addition, the composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention may have excellent moisture barrier properties.

In addition, the composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention may be environmentally friendly and easily reproduced.

However, the effects of the present invention are not limited to the above-described effects, and may be variously extended within a range that does not deviate from the spirit and scope of the present invention.

1 is a cross-sectional view of a composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention.
2 is a diagram schematically showing the structure of a three-dimensional network structure included in a natural product blocking layer according to an exemplary embodiment of the present invention.
3 is a cross-sectional view of a composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention.
4 is a cross-sectional view of a composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention.
Figure 5a shows the result of measuring the IR spectrum of the natural product blocking layer prepared in Preparation Example 1, and Figure 5b shows the result of measuring the IR spectrum of the natural product blocking layer prepared in Comparative Preparation Example 1.
Figure 6a is a cross-sectional view of a sample for evaluating the interlayer adhesiveness of the composite film for a vacuum insulation panel of Example 1 and Comparative Example 1, and Figure 6b is a cross-sectional view of a sample for evaluating the interlayer adhesiveness of the composite film for a vacuum insulation panel of Comparative Example 2 to be.

Throughout the present specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.

Throughout the present specification, when a member is said to be located “on” another member, this includes not only a case where a member is in contact with another member, but also a case where another member exists between the two members.

Throughout this specification, “layer” represents a broad concept including “film, stretched sheet, unstretched sheet, or similar form”.

Hereinafter, the present invention will be described in more detail.

An exemplary embodiment of the present invention is a base layer comprising a base film; a natural blocking layer provided on one surface of the base layer and containing a natural hydrogel; a first adhesive layer provided on one surface of the natural product blocking layer; A second adhesive layer provided on the other surface of the substrate layer; a first blocking layer provided on one surface of the first adhesive layer; and a second blocking layer provided on one surface of the second adhesive layer.

The composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention may have excellent interlayer adhesion and gas barrier properties. Specifically, interlayer adhesion between the base layer and the natural product blocking layer included in the composite film for the vacuum insulation panel may be excellent.

In addition, the composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention may have excellent moisture barrier properties.

In addition, the composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention may be environmentally friendly and easily reproduced. Specifically, since the composite film for a vacuum insulation panel includes a natural product blocking layer, the composite film for a vacuum insulation panel can be easily separated by immersing the composite film for a vacuum insulation panel in water to dissolve the natural product blocking layer. , can be recycled and can be environmentally friendly.

1 is a cross-sectional view of a composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention. Referring to FIG. 1 , a composite film 100 for a vacuum insulation panel according to an exemplary embodiment of the present invention includes a substrate layer 10, a natural product blocking layer 20, a first adhesive layer 31, and a second adhesive layer 32. , The first blocking layer 40 and the second blocking layer 50 may be included. Specifically, the composite film 100 for a vacuum insulation panel includes a first blocking layer 40, a first adhesive layer 31, a natural product blocking layer 20, a base layer 10, a second adhesive layer 32, and a second adhesive layer 32. The blocking layer 50 may be sequentially stacked and provided.

A composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention has a structure in which a first blocking layer, a first adhesive layer, a natural product blocking layer, a base layer, a second adhesive layer, and a second blocking layer are laminated, thereby Compared to the composite film for vacuum insulation panels, interlayer adhesion, gas barrier properties, and moisture barrier properties may be excellent. Specifically, the composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention has a sandwich structure in which a natural product blocking layer and a base layer are provided between a first blocking layer and a second blocking layer, so that the base layer, the blocking layer and Compared to the composite film in which coating layers are sequentially provided and the composite film in which a barrier layer is provided between the first base layer and the second base layer, interlayer adhesion, gas barrier properties, and moisture barrier properties may be excellent. In particular, the composite film for a vacuum insulation panel may have excellent gas barrier properties even under a humidity condition of, for example, 40% to 60% by including the above-described laminated structure.

According to one embodiment of the present invention, the base film may include at least one of a polyolefin-based film and a polyester-based film. For example, the polyolefin-based film may include at least one of a polyethylene film and a polypropylene film. In addition, the polyester-based film may include at least one of a polyethylene terephthalate film, a polybutylene terephthalate film, and a polyethylene-2,6-naphthalenedicarboxylate (PEN) film. When the above-described type of film is used as the base film, the ease of processing and durability of the composite film for a vacuum insulation panel may be improved.

According to one embodiment of the present invention, the thickness of the base film may be 10 μm or more and 50 μm or less. Specifically, the thickness of the base film is 12 μm or more and 50 μm or less, 15 μm or more and 45 μm or less, 20 μm or more and 40 μm or less, 20 μm or more and 30 μm or less, 10 μm or more and 40 μm or less, 15 μm or more and 30 μm or less. , 20 μm or more and 50 μm or less, 20 μm or more and 45 μm or less, or 25 μm or more and 35 μm or less. When the thickness of the base film is within the aforementioned range, mechanical properties of the composite film for a vacuum insulation panel may be further improved.

According to an exemplary embodiment of the present invention, the natural material blocking layer may be included in the composite film for a vacuum insulation panel to block oxygen and moisture. The natural product blocking layer may include a natural product hydrogel. Specifically, the natural product blocking layer may include a three-dimensional network structure containing a natural product hydrogel. Through this, the oxygen barrier property of the natural blocking layer may be further improved.

According to an exemplary embodiment of the present invention, the natural product blocking layer may include a cured product of a natural product composition including the natural product and a silane-based coupling agent. Specifically, the natural product may be a raw material for preparing the natural product hydrogel, and the natural product blocking layer may include a heat-cured product (heat-treated product) of the natural product composition. More specifically, by heat-treating the natural product composition, a three-dimensional network structure in which a silane-based coupling agent is dispersed and crosslinked inside the natural product hydrogel derived from the natural product may be formed. That is, the three-dimensional network structure may include a natural hydrogel and a silane-based coupling agent. As described above, when the natural product blocking layer includes a three-dimensional network structure, physical properties such as mechanical properties and oxygen blocking ability of the natural product blocking layer can be further improved.

2 is a diagram schematically showing the structure of a three-dimensional network structure included in a natural product blocking layer according to an exemplary embodiment of the present invention. Referring to FIG. 2 , the natural product blocking layer may have, for example, a structure in which a silane-based coupling agent 2 is dispersed and cross-linked in a protein hydrogel 1 . The structure of the three-dimensional network structure can be confirmed from IR spectrum analysis of Experimental Example 1 to be described later.

According to an exemplary embodiment of the present invention, the natural hydrogel may include at least one of proteins and carbohydrates. Specifically, the natural hydrogel may include at least a protein. In addition, the natural product, which is a raw material of the natural product hydrogel, may include at least one of the protein and the carbohydrate. Specifically, the natural product may include at least protein.

For example, the protein is whey protein isolate (WPI), whey protein concentrate (WPC), soy protein isolate (SPI), rice protein isolate (RPI), oats At least one of oat protein isolate (OPI), pea protein isolate (PPI), casein, sodium caseinate, corn zein, gelatin and wheat protein may contain one.

The protein is a high molecular compound in which a plurality of amino acid units are linked by peptide bonds, and may exhibit excellent oxygen barrier properties by the plurality of peptide bonds. In addition, when a natural product blocking layer is formed using the natural product composition containing the protein, hydrogen bonds or covalent bonds may be formed between the peptide bonds, and furthermore, in a hydrogel structure containing a large amount of water, A dimensional network structure can be formed. Through this, it is possible to effectively improve the oxygen blocking ability of the composite film for a vacuum insulation panel including the natural material blocking layer.

According to an exemplary embodiment of the present invention, the natural hydrogel may include carbohydrates. In addition, the natural product may include carbohydrates. For example, the carbohydrate may include at least one of pullulan, carrageenan, chitosan, starch, agar, and pectin. Mechanical properties of the natural blocking layer may be improved by using the natural hydrogel containing the carbohydrate.

According to an exemplary embodiment of the present invention, the amount of the natural product included in the natural product composition may be 3 parts by weight or more and 30 parts by weight or less, 3.5 parts by weight or more and 15 parts by weight or less, based on 100 parts by weight of the natural product composition. When the content of the natural material is within the above range, the oxygen barrier property of the natural material blocking layer can be effectively improved.

According to one embodiment of the present invention, the natural product blocking layer may include a silane-based coupling agent. As described above, the natural product blocking layer may include the natural product hydrogel and the silane-based coupling agent dispersed and crosslinked inside the natural product hydrogel. By using the silane-based coupling agent, mechanical properties of the three-dimensional network structure included in the natural product blocking layer may be improved, and oxygen barrier properties of the natural product blocking layer may be improved.

The silane-based coupling agent may include a silane compound containing at least one of a vinyl group, an amino group, an epoxy group, an acryl group, a methacrylic group, a methoxy group, an ethoxy group, a trimethoxy group, and a triethoxy group. For example, the silane-based coupling agent may include at least one of aminosilane, epoxysilane, and acrylic acid silane.

According to an exemplary embodiment of the present invention, the content of the silane-based coupling agent included in the natural product composition is 5 parts by weight or more and 30 parts by weight or less, 5 parts by weight or more and 15 parts by weight or less, based on 100 parts by weight of the natural product composition. can When the content of the silane-based coupling agent is within the above range, mechanical properties of the natural blocking layer can be effectively improved.

According to an exemplary embodiment of the present invention, the weight ratio of the natural product and the silane-based coupling agent included in the natural product composition may be 10:1 to 1:10. Specifically, it may be 8:1 to 1:8, 5:1 to 1:5, or 3:1 to 1:3. In addition, the content of the silane-based coupling agent included in the natural product composition may be greater than that of the natural product. Specifically, the weight ratio of the natural product and the silane-based coupling agent included in the natural product composition is 1:1.1 to 1:10, 1:1.5 to 1:8, 1:1.5 to 1:5, or 1:1.5 to 1 :3 can be. When the weight ratio of the natural product and the silane-based coupling agent included in the natural product composition is within the above range, the adhesion of the natural product blocking layer to the base layer can be effectively improved, and the natural product blocking layer can contain gas (oxygen) barrier properties can be effectively improved.

According to one embodiment of the present invention, the natural product composition may include a filler. The filler includes at least one of sorbitol, fructose, sucrose, mannitol, propylene glycol, glycerol, and polyethylene glycol. can do.

The filler is disposed in the hole between the natural hydrogel three-dimensional network structure and fills the hole, thereby increasing the oxygen barrier property (barrier property) of the natural product barrier layer and smoothing the surface. can play a role in

According to an exemplary embodiment of the present invention, the content of the filler may be 3 parts by weight or more and 30 parts by weight or less, 3.5 parts by weight or more and 15 parts by weight or less, based on 100 parts by weight of the natural product composition. When the content of the filler satisfies the above range, mechanical properties and oxygen barrier properties of the composite film for a vacuum insulation panel may be improved. In addition, when the content of the filler is within the above range, it is possible to suppress the phenomenon in which the natural product barrier layer is cracked and separated from the substrate layer, and when the composite film for a vacuum insulation panel is stored for a long period of time, the filler is added to the surface of the natural product barrier layer. It is possible to prevent the phenomenon of deterioration of oxygen barrier property by migration.

According to an exemplary embodiment of the present invention, the method for preparing the natural product blocking layer includes preparing a natural product composition by adding a silane-based coupling agent and a filler to a natural product aqueous solution containing a natural product, which is a raw material of a natural product hydrogel; preparing a natural product composition containing a heat-treated product by heating and cooling the natural product composition; and preparing a natural product blocking layer by applying a natural product composition including the heat-treated product to the substrate layer and drying the natural product composition. Through the above-described method, it is possible to easily prepare a natural blocking layer, and to manufacture a natural blocking layer having excellent oxygen barrier properties and excellent adhesion to a substrate layer.

The contents of the natural product, the silane-based coupling agent, and the filler included in the natural product composition are the same as described above.

Distilled water or purified water may be used as a solvent for the natural product aqueous solution. The amount of the solvent may be 50 parts by weight or more and 99 parts by weight or less, 70 parts by weight or more and 90 parts by weight or less, based on 100 parts by weight of the natural product composition.

A natural product composition including a heat-treated product may be prepared by heat-treating for a sufficient chemical reaction between components included in the natural product composition and then cooling the product. The heat treatment may be performed at a temperature of 70 °C or more and 120 °C or less for 1 hour to 5 hours. Specifically, the heat treatment may be performed at a temperature of 80 °C or more and 100 °C or less for 2 to 3 hours. By adjusting the heat treatment temperature and time range within the above range, mechanical properties of the natural barrier layer can be improved.

Meanwhile, the natural product blocking layer may be prepared as follows. For example, the natural product composition may be prepared by a one-step reaction in which a coating agent is directly applied by inducing a hydrolysis reaction of a silane-based coupling agent and a natural product-silane-based coupling agent reaction simultaneously. Alternatively, the natural product composition may be prepared by a two-step reaction in which a hydrolyzed silane-based coupling agent is first prepared, a natural product-silane-based coupling agent reaction is sufficiently completed, and then a coating agent is prepared.

The natural product composition may be applied on the base layer through a method used in the art. For example, it may be applied by a method such as spin coating, spray coating, dip coating, slit coating, slot die coating, bar coating, etc., but applying the natural product composition It does not limit the method.

After applying the natural product composition on the base layer, the natural product composition may be dried to prepare a natural product barrier layer including a heat-cured product (heat-treated product) of the natural product composition.

According to an exemplary embodiment of the present invention, the natural blocking layer may have a thickness of 1 μm or more and 10 μm or less. Specifically, the natural blocking layer may have a thickness of 1 μm to 8 μm, 1 μm to 5 μm, 1 μm to 3 μm, or 5 μm to 10 μm. When the thickness of the natural product blocking layer is within the above range, the interlayer adhesion between the natural product blocking layer and the substrate layer can be effectively improved, and the gas barrier properties of the composite film for a vacuum insulation panel can be further improved.

According to one embodiment of the present invention, the thickness ratio of the natural product blocking layer and the base film may be 1:10 to 1:50. Specifically, the thickness ratio of the natural material blocking layer and the base film is 1:20 to 1:40, 1:25 to 1:35, 1:15 to 1:25, 1:20 to 1:30, 1:10 to 1:25, or 1:15 to 1:30. When the thickness ratio of the natural product blocking layer and the base film is within the above-described range, it is possible to effectively prevent a decrease in interlayer adhesive strength between the natural product blocking layer and the base layer, and thus, during the processing of the composite film for a vacuum insulation panel, the Separation of the natural product blocking layer from the base layer can be effectively suppressed.

According to one embodiment of the present invention, each of the first adhesive layer and the second adhesive layer may independently include at least one of an oil-based adhesive and a water-based adhesive. Specifically, each of the first adhesive layer and the second adhesive layer is independently a polyurethane-based resin, a polyamide-based resin, an ethylene-vinyl acetate-based resin, or a polyvinyl acetate-based resin. Acetate-based resin, phenol-based resin, melamine-based resin, urea-based resin, epoxy-based resin, polyester-based resin, polyvinyl alcohol-based resin , acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), alkyd, acetyl cellulose, nitro cellulose, starch and hot melt thermoplastic polyurethane )-based resins. The oil-based adhesive layer may be formed using an oil-based adhesive known in the art. For example, the oil-based adhesive layer may include an oil-based polyurethane-based resin. The water-based adhesive layer may include a water-based adhesive known in the art. For example, it may include an aqueous polyurethane-based resin, a polyvinylpyrrolidone resin, a polyvinyl alcohol resin, an aqueous acrylic-based resin, an epoxy resin, a phenolic resin, starch, or a combination thereof.

According to an exemplary embodiment of the present invention, the first adhesive layer and the second adhesive layer may each include a cured product of an adhesive composition. The adhesive composition may include an adhesive and a curing agent. The adhesive may include a polyester-based resin, and the curing agent may include a polyisocyanate-based curing agent. The composite film for a vacuum insulation panel including the first adhesive layer and the second adhesive layer formed from the adhesive composition may have excellent interlayer adhesion and sealing strength.

According to an exemplary embodiment of the present invention, the weight ratio of the curing agent and the adhesive included in the adhesive composition may be 1:3 to 1:15. Specifically, the weight ratio of the curing agent to the adhesive is 1:5 to 1:13, 1:7.5 to 1:10, 1:3 to 1:10, 1:5.5 to 1:10, 1:5 to 1:15 , or 1:7.5 to 1:13. When the weight ratio of the curing agent and the adhesive included in the adhesive composition is within the above range, the adhesive strength of the first and second adhesive layers including a cured product of the adhesive composition can be effectively improved.

According to an exemplary embodiment of the present invention, based on 100 parts by weight of the adhesive composition, the content of the adhesive may be 30 parts by weight or more and 50 parts by weight or less. Specifically, based on 100 parts by weight of the adhesive composition, the content of the adhesive is 35 parts by weight or more and 47.5 parts by weight or less, 37.5 parts by weight or more and 45 parts by weight or less, 30 parts by weight or more and 45 parts by weight or less, or 40 parts by weight or more 50 parts by weight or more. It may be less than parts by weight. By adjusting the content of the adhesive within the above range, it is possible to improve the adhesive strength of the first and second adhesive layers.

According to an exemplary embodiment of the present invention, based on 100 parts by weight of the adhesive composition, the content of the curing agent may be 3 parts by weight or more and 10 parts by weight or less. Specifically, based on 100 parts by weight of the adhesive composition, the content of the curing agent is 3.5 parts by weight or more and 8.5 parts by weight or less, 5 parts by weight or more and 7 parts by weight or less, 3 parts by weight or more and 6 parts by weight or less, or 5 parts by weight or more 10 It may be less than parts by weight. When the amount of the curing agent is within the above-described range, the adhesive composition may be stably cured, and deterioration in adhesive strength of the first and second adhesive layers may be effectively prevented.

According to one embodiment of the present invention, the adhesive composition may include a solvent. As the solvent, those used in the art may be used without limitation. For example, ethyl acetate may be used as the solvent, but the type of the solvent is not limited. Based on 100 parts by weight of the adhesive composition, the content of the solvent may be 40 parts by weight or more and 60 parts by weight or less. By adjusting the content of the solvent within the above-mentioned range, it is possible to improve the coating property of the adhesive composition, and it is possible to form a more flat surface of the first and second adhesive layers produced.

According to one embodiment of the present invention, the thickness of each of the first adhesive layer and the second adhesive layer may be 1 μm or more and 10 μm or less. Specifically. The thickness of each of the first adhesive layer and the second adhesive layer may be 2 μm or more and 9 μm or less, 3 μm or more and 7 μm or less, 1 μm or more and 5 μm or less, 1 μm or more and 3 μm or less, or 5 μm or more and 10 μm or less. When the thickness of each of the first and second adhesive layers is within the aforementioned range, it is possible to prevent deterioration in interlayer adhesive strength and sealing strength of the composite film for a vacuum insulation panel.

According to one embodiment of the present invention, the thickness ratio of the natural product blocking layer and the first adhesive layer may be 1:1 to 1:10. Specifically, the thickness ratio of the natural product blocking layer and the first adhesive layer is 1:2 to 1:8, 1:3 to 1:6, 1:2 to 1:5, 1:2.5 to 1:4.5, 1: 3 to 1:4, 1:2 to 1:3, or 1:3 to 1:5. When the thickness ratio between the natural product blocking layer and the first adhesive layer is within the above-described range, the adhesive strength between the natural product blocking layer and the first adhesive layer is improved while suppressing deterioration in gas barrier performance and moisture barrier capability of the composite film for a vacuum insulation panel. Thus, the sealing strength of the composite film for a vacuum insulation panel can be effectively improved.

3 is a cross-sectional view of a composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention. Referring to FIG. 3 , the base layer 10 includes a base film 11, a primer layer 12a provided on one side of the base film 11, and a primer layer 12b provided on the other side of the base film 11. can include In addition, the first blocking layer 40 may include a first base film 41 and a first inorganic blocking layer 42 provided on one surface of the first base film 41 . In addition, the second blocking layer 50 may include a second base film 51 and a second inorganic blocking layer 52 provided on one surface of the second base film 51 . Referring to FIG. 3 , the composite film 100 for a vacuum insulation panel includes a first base film 41, a first inorganic blocking layer 42, a first adhesive layer 31, a natural product blocking layer 20, a primer layer ( 12a), the base film 11, the primer layer 12b, the second adhesive layer 32, the second inorganic blocking layer 52, and the second base film 51 may be sequentially stacked and provided.

According to one embodiment of the present invention, the base layer may include a primer layer provided on one side and the other side of the base film, and the natural product blocking layer may be provided in direct contact with the primer layer. By providing a primer layer on one side and the other side of the base film, adhesion to the natural product blocking layer and the second adhesive layer can be effectively improved. Through this, it is possible to further improve the interlayer adhesion and sealing strength of the composite film for the vacuum insulation panel.

The primer layer may include a urethane-based primer. Adhesion of the base layer to the natural product blocking layer and the second adhesive layer may be effectively improved by introducing the primer layer including the urethane-based primer onto one side and the other side of the base film, as described above. Meanwhile, as the primer layer, a primer layer used in the art may be used.

According to one embodiment of the present invention, one surface and the other surface of the base film may be surface-treated by corona treatment or plasma treatment, and the natural product blocking layer may be provided in direct contact with one surface of the surface-treated base film. By surface-treating one surface and the other surface of the base film by corona treatment or plasma treatment, adhesiveness to the natural product blocking layer and the second adhesive layer can be effectively improved. Through this, it is possible to further improve the interlayer adhesion and sealing strength of the composite film for the vacuum insulation panel. Corona treatment of one side and the other side of the base film may be performed through a corona treatment method used in the art, and plasma treatment may be performed through a plasma treatment method used in the art.

According to an exemplary embodiment of the present invention, the first blocking layer may include a first base film; and a first inorganic blocking layer provided on the first base film and containing an inorganic material, wherein the first inorganic blocking layer may be provided on the first adhesive layer.

The first base film may include at least one of a polyolefin-based film and a polyester-based film. For example, the polyolefin-based film may include at least one of a polyethylene film and a polypropylene film. In addition, the polyester-based film may include at least one of a polyethylene terephthalate film, a polybutylene terephthalate film, and a polyethylene-2,6-naphthalenedicarboxylate (PEN) film. When using the above-described type of film as the first base film, the ease of processing and durability of the composite film for a vacuum insulation panel may be improved.

According to one embodiment of the present invention, the thickness of the first base film may be greater than or equal to 5 μm and less than or equal to 20 μm. Specifically, the thickness of the first base film is 7.5 μm or more and 17.5 μm or less, 10 μm or more and 15 μm or less, 5 μm or more and 15 μm or less, 8 μm or more and 13 μm or less, 10 μm or more and 20 μm or less, or 10 μm or more. It may be 17.5 μm or less. By using the first base film having a thickness within the aforementioned range, it is possible to suppress deterioration in durability and workability of the composite film for a vacuum insulation panel.

According to one embodiment of the present invention, the first inorganic blocking layer may include an inorganic material. Specifically, the first inorganic blocking layer may include silicon oxide or aluminum oxide. For example, the silicon oxide is SiO _x , and x may be a real number of 1 or more and 2 or less. In addition, the aluminum oxide is Al _y O _z , and y and z may be real numbers of 1 or more and 3 or less. By using the first inorganic barrier layer containing the aforementioned inorganic material, gas barrier properties of the composite film for a vacuum insulation panel can be effectively improved.

According to one embodiment of the present invention, the thickness ratio of the first base film and the base film may be 5:1 to 1:5. Specifically, the thickness ratio of the first base film and the base film is 4:1 to 1:4, 3:1 to 1:3, 2:1 to 1:2, 1:1.5 to 1:5, 1: 2 to 1:4, 1:2 to 1:3, 1:1.5 to 1:3, or 1:1.5 to 1:2. When the thickness ratio of the first base film and the base film is within the above-described range, durability of the composite film for a vacuum insulation panel may be improved while workability may be prevented from being deteriorated.

According to one embodiment of the present invention, the second blocking layer may include a second base film; and a second inorganic blocking layer provided on the second base film and containing an inorganic material, wherein the second inorganic blocking layer may be provided on the second adhesive layer.

The second base film may include at least one of a polyolefin-based film and a polyester-based film. For example, the polyolefin-based film may include at least one of a polyethylene film and a polypropylene film. In addition, the polyester-based film may include at least one of a polyethylene terephthalate film, a polybutylene terephthalate film, and a polyethylene-2,6-naphthalenedicarboxylate (PEN) film. When using the above-described type of film as the second base film, the ease of processing and durability of the composite film for a vacuum insulation panel may be improved.

According to one embodiment of the present invention, the second base film may have a thickness of 5 μm or more and 20 μm or less. Specifically, the thickness of the second base film is 7.5 μm or more and 17.5 μm or less, 10 μm or more and 15 μm or less, 5 μm or more and 15 μm or less, 8 μm or more and 13 μm or less, 10 μm or more and 20 μm or less, or 10 μm or more. It may be 17.5 μm or less. By using the second base film having a thickness within the above-described range, it is possible to suppress deterioration in durability and workability of the composite film for a vacuum insulation panel.

According to one embodiment of the present invention, the second inorganic blocking layer may include an inorganic material. Specifically, the second inorganic blocking layer may include silicon oxide or aluminum oxide. For example, the silicon oxide is SiO _x , and x may be a real number of 1 or more and 2 or less. In addition, the aluminum oxide is Al _y O _z , and y and z may be real numbers of 1 or more and 3 or less. By using the second inorganic barrier layer containing the aforementioned inorganic material, gas barrier properties of the composite film for a vacuum insulation panel can be effectively improved.

According to one embodiment of the present invention, the thickness ratio of the second base film and the base film may be 5:1 to 1:5. Specifically, the thickness ratio of the second base film and the base film is 4:1 to 1:4, 3:1 to 1:3, 2:1 to 1:2, 1:1.5 to 1:5, 1: 2 to 1:4, 1:2 to 1:3, 1:1.5 to 1:3, or 1:1.5 to 1:2. When the thickness ratio of the second base film and the base film is within the above-described range, durability of the composite film for a vacuum insulation panel may be improved while reducing workability may be suppressed.

According to an exemplary embodiment of the present invention, the composite film for a vacuum insulation panel has the first blocking layer provided on one side of the natural product blocking layer and the second blocking layer provided on the other side of the natural product blocking layer, thereby improving moisture permeability. can be reduced, thereby effectively suppressing the deterioration of the gas (oxygen) blocking ability of the natural blocking layer.

4 is a cross-sectional view of a composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention. Referring to FIG. 4 , the first blocking layer 40 may include a first base film 41 , a first inorganic blocking layer 42 and a first protective layer 43 . In addition, the second blocking layer 50 may include a second base film 51 , a second inorganic blocking layer 52 , and a second protective layer 53 .

According to one embodiment of the present invention, the first blocking layer may include a first protective layer provided on one surface of the first inorganic blocking layer. Also, the second blocking layer may include a second protective layer provided on one surface of the second inorganic blocking layer. By providing a first protective layer on one surface of the first inorganic barrier layer and providing a second protective layer on one surface of the second inorganic layer, the moisture barrier properties of the first and second barrier layers are effectively improved. can make it As the first protective layer and the second protective layer, components having moisture blocking performance in the art may be used without limitation.

According to one embodiment of the present invention, the composite film for a vacuum insulation panel may be a film for a food packaging material. As described above, the composite film for a vacuum insulation panel has excellent interlayer adhesion, oxygen barrier properties, and gas barrier properties, and thus can be easily applied as a film for food packaging materials.

Hereinafter, examples will be described in detail to explain the present invention in detail. However, embodiments according to the present invention can be modified in many different forms, and the scope of the present invention is not construed as being limited to the embodiments described below. The embodiments herein are provided to more completely explain the present invention to those skilled in the art.

manufacturing example

Preparation of natural product composition

Preparation Example 1

A natural product aqueous solution was prepared by slowly adding 5 g of whey protein as a natural product to 92 g of distilled water while stirring. A natural product composition was prepared by adding and dissolving 8 g of amino silane as a silane-based coupling agent in the natural product aqueous solution, and then adding 5 g of sorbitol as a filler. 1N NaOH was added to the natural product composition to adjust the pH to 9. Thereafter, the pH-adjusted natural product composition was stirred using a mechanical stirrer at 300 rpm, heated at 90° C. for 120 minutes, and then cooled to room temperature to prepare a natural product composition containing a heat-treated product.

Comparative Preparation Example 1

A natural product composition containing a heat-treated product was prepared in the same manner as in Preparation Example 1, except that a silane-based coupling agent was not added.

Preparation of adhesive composition

Preparation Example 2

A polyester-based resin, TM-585-60K-S (Toyo INK Co.) as an adhesive, CAT-10 (Toyo INK Co., Ltd.), a polyisocyanate-based curing agent, and ethyl acetate as a solvent were prepared as a curing agent. Thereafter, 21.2 g of ethyl acetate was added to the beaker, and the beaker and the impeller were set in a stirrer and stirred at 300 rpm. 18 g of the adhesive and 2.2 g of the curing agent were sequentially added at intervals of 3 minutes to the solvent being stirred, and stirred for 10 minutes to prepare an adhesive composition.

Example 1

A substrate layer (SH86; SKC) having a primer layer containing a urethane-based primer on one side and the other side of a polyethylene terephthalate film having a thickness of 23 μm was prepared.

An inorganic film (Seoil Corporation) in which aluminum oxide was deposited on one side of a polyethylene terephthalate (PET) film having a thickness of 12 μm was prepared as a first and second blocking layer.

The natural product composition prepared in Preparation Example 1 was coated on the primer layer of the prepared substrate layer with an applicator (YBA-5). Thereafter, the base layer coated with the natural product composition was placed in an oven and dried at 100° C. for 3 minutes to prepare a base layer with a natural blocking layer having a thickness of 1 μm.

The adhesive composition prepared in Preparation Example 2 was coated on the first inorganic blocking layer (aluminum oxide deposition layer) of the prepared first blocking layer using a bar coater. Thereafter, the first blocking layer coated with the adhesive composition was placed in an oven and heat-treated at 80° C. for 5 seconds to prepare a first blocking layer having a first adhesive layer. Then, in the same manner as above, a second blocking layer having a second adhesive layer was prepared.

The first blocking layer provided with the first adhesive layer is fixed to a flat plate, and the base layer provided with the natural product blocking layer is laminated on the first blocking layer so that the natural product blocking layer comes into contact with the first adhesive layer, and the first lamination is performed by a dry lamination method. did

The primer of the laminate in which the primary laminate is fixed to a flat plate and the second blocking layer provided with the second adhesive layer is primarily laminated so that the second adhesive layer comes into contact with the exposed primer layer of the primary laminate. The composite film for a vacuum insulation panel shown in FIG. 3 was prepared by laminating on layers and performing secondary lamination using a dry lamination method. At this time, the thickness of each of the first adhesive layer and the second adhesive layer after dry lamination was 3 μm.

Thereafter, the composite film for a vacuum insulation panel was aged at 40° C. for 3 days to finally prepare a composite film for a vacuum insulation panel.

Comparative Example 1

In Example 1, a composite film for a vacuum insulation panel was prepared in the same manner as in Example 1, except that the natural product composition prepared in Comparative Preparation Example 1 was used instead of the natural product composition prepared in Preparation Example 1.

Comparative Example 2

A composite film for a vacuum insulation panel was prepared in the same manner as in Example 1, except that a substrate layer not provided with a primer layer was used in Example 1.

Comparative Example 3

Aging the primary laminated laminate (first blocking layer / first adhesive layer / natural blocking layer / base layer provided with a primer layer on both sides) prepared in Example 1 at 40 ° C. for 3 days, A composite film for a vacuum insulation panel was prepared.

Experimental example

Experimental Example 1: IR spectrum analysis

IR spectra were measured for the substrate layer provided with the natural product blocking layer prepared in Example 1 and the substrate layer provided with the natural product blocking layer prepared in Comparative Example 1 to confirm crosslinking. The results are shown in Figures 5a and 5b, respectively.

Figure 5a shows the result of measuring the IR spectrum of the natural product blocking layer prepared in Preparation Example 1, and Figure 5b shows the result of measuring the IR spectrum of the natural product blocking layer prepared in Comparative Preparation Example 1.

5a and 5b, the natural product blocking layer of Example 1 showed a higher peak at 900 to 1200 cm ⁻¹ corresponding to CN bonding, compared to the natural product blocking layer of Comparative Example 1, and a peak of 2800 corresponding to CH bonding. It was confirmed that the peak appeared high at 3000 cm ^-1 .

Through this, it can be confirmed that the natural product blocking layer of Example 1 has a structure in which the silane-based coupling agent is dispersed and crosslinked inside the protein hydrogel having a three-dimensional network structure.

Experimental Example 2: Evaluation of interlayer adhesive strength

Figure 6a is a cross-sectional view of a sample for evaluating the interlayer adhesiveness of the composite film for a vacuum insulation panel of Example 1 and Comparative Example 1, and Figure 6b is a cross-sectional view of a sample for evaluating the interlayer adhesiveness of the composite film for a vacuum insulation panel of Comparative Example 2 to be.

6A and 6B, in the manufacture of the composite films for vacuum insulation panels of Example 1, Comparative Example 1 and Comparative Example 2, the ends of the first adhesive layer and the second adhesive layer are 30 mm from the outside. Spaced apart (d), samples for evaluation of interlayer adhesive strength were prepared.

Then, through the T-Peel Test, the peel strength in the first adhesive layer and the second adhesive layer was measured, and the results are shown in Tables 1 and 2 below.

Example 1 1st adhesive layer 2nd adhesive layer peel strength
(gf/25mm) 798 582 Exfoliation Exfoliation X Exfoliation X

Comparative Example 1 Comparative Example 2 1st adhesive layer 2nd adhesive layer 1st adhesive layer 2nd adhesive layer peel strength
(gf/25mm) 221.67 850.32 840 618 Exfoliation full exfoliation Exfoliation X partial exfoliation partial exfoliation

Referring to Tables 1 and 2, in the case of Example 1 in which the primer layer was introduced into the base layer, it was confirmed that the first adhesive layer and the second adhesive layer did not separate from the adjacent layer during the interlayer adhesive strength evaluation process.

On the other hand, in the case of Comparative Example 1 using the natural product composition prepared in Comparative Preparation Example 1 without adding a silane-based coupling agent, a primer layer was introduced into the substrate layer, but in the process of evaluating the interlayer adhesive strength, the first adhesive layer was It was confirmed that it was completely peeled off.

In addition, in the case of Comparative Example 2 in which the primer layer was not introduced into the substrate layer, it was confirmed that the first adhesive layer and the second adhesive layer were partially separated from the adjacent layer by about 2 cm in the interlayer adhesive strength evaluation process.

In Tables 1 and 2, the peel strength measured in Example 1, Comparative Example 1, and Comparative Example 2 means the peel strength measured at the time the PET film of the first barrier layer is torn in the interlayer adhesive strength evaluation process. do. Referring to Table 2, it was confirmed that Comparative Example 2 had higher peel strength in the first adhesive layer and the second adhesive layer than in Example 1, but as partial peeling occurred in Comparative Example 2, the peel strength was greater. It can be seen that it is measured.

Through this, it can be seen that the composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention has excellent interlayer adhesive strength.

Experimental Example 3: Oxygen barrier property (barrier property) and water barrier property (barrier property) evaluation

With respect to the composite films for vacuum insulation panels prepared in Example 1 and Comparative Example 3, oxygen permeability and moisture permeability were measured through the following methods.

Oxygen permeability evaluation method: Oxygen permeability was measured using an OXTRAN 2/21 oxygen permeability tester manufactured by MOCON, and the result was evaluated. The oxygen permeability indicates the amount of oxygen in the composite film for a vacuum insulation panel for 24 hours under conditions of a temperature of 23±1 °C, humidity (relative humidity) of 0% and 50%, and O ₂ concentration of 100%.

Water permeability evaluation method: The water permeability was evaluated using a PERMATRAN-W 3/34G permeability tester manufactured by MOCON. The moisture permeability represents the amount of moisture that has passed through the composite film for a vacuum insulation panel per unit time under conditions of a temperature of 38 ± 1 °C and a humidity of 100%.

oxygen permeability
(cc/m ² ·day) moisture permeability
(g/m ² ·day) 23℃/
RH 0% 23℃/
RH 50% 38 ℃ Example 1 0.06 0.08 0.9309 Comparative Example 3 0.12 0.42 2.1989

Referring to Table 3, it can be seen that the composite film for a vacuum insulation panel prepared in Example 1 has lower oxygen permeability and moisture permeability than the composite film for a vacuum insulation panel prepared in Comparative Example 3. In particular, it can be seen that the composite film for a vacuum insulation panel prepared in Example 1 under a relative humidity of 50% has about 5 times lower acidity permeability than the composite film for a vacuum insulation panel prepared in Comparative Example 3.

Through this, it can be seen that the composite film for a vacuum insulation panel according to an exemplary embodiment of the present invention has excellent oxygen barrier properties and moisture barrier properties.

The foregoing detailed description is intended to illustrate and explain the present invention. In addition, the foregoing merely represents and describes preferred embodiments of the present invention, and as described above, the present invention can be used in various other combinations, modifications, and environments, and the scope of the inventive concept disclosed herein, the writings Changes or modifications are possible within the scope equivalent to the disclosure and / or within the scope of skill or knowledge in the art. Accordingly, the above detailed description of the invention is not intended to limit the invention to the disclosed embodiments. Also, the appended claims should be construed to cover other embodiments as well.

100: composite film for vacuum insulation panel
1: 3-dimensional network protein hydrogel
2: cross-linked silane-based coupling agent
10: base layer 11: base film
12a, 12b: Primer layer 20: Natural product blocking layer
31: first adhesive layer 32: second adhesive layer
40: first blocking layer 41: first base film
42: first inorganic barrier layer 43: first protective layer
50: second blocking layer 51: second base film
52: second inorganic barrier layer 53: second protective layer

Claims (12)

A base layer comprising a base film;
a natural blocking layer provided on one surface of the base layer and containing a natural hydrogel;
a first adhesive layer provided on one surface of the natural product blocking layer;
A second adhesive layer provided on the other surface of the substrate layer;
a first blocking layer provided on one surface of the first adhesive layer; and
A composite film for a vacuum insulation panel comprising a; second blocking layer provided on one surface of the second adhesive layer.
According to claim 1,
The base layer includes a primer layer provided on one side and the other side of the base film,
The natural product blocking layer is a composite film for a vacuum insulation panel provided in direct contact with the primer layer.
According to claim 1,
One side and the other side of the base film are surface treated by corona treatment or plasma treatment,
The natural product blocking layer is a composite film for a vacuum insulation panel provided in direct contact with one surface of the surface-treated base film.
According to claim 1,
The thickness ratio of the natural product blocking layer and the first adhesive layer is 1: 1 to 1: 10 of the composite film for a vacuum insulation panel.
According to claim 1,
The base film is a composite film for a vacuum insulation panel comprising at least one of a polyolefin-based film and a polyester-based film.
According to claim 1,
The first blocking layer,
a first base film; and
A first inorganic blocking layer provided on the first base film and containing an inorganic material;
The first inorganic blocking layer is a composite film for a vacuum insulation panel provided on the first adhesive layer.
According to claim 6,
The thickness ratio of the first base film and the base film is 5: 1 to 1: 5 of the composite film for a vacuum insulation panel.
According to claim 1,
The second blocking layer,
a second base film; and
A second inorganic blocking layer provided on the second base film and containing an inorganic material;
The second inorganic blocking layer is a composite film for a vacuum insulation panel provided on the second adhesive layer.
According to claim 8,
The thickness ratio of the second base film and the base film is 5: 1 to 1: 5 of the composite film for a vacuum insulation panel.
According to claim 1,
The natural hydrogel is a composite film for a vacuum insulation panel comprising at least one of protein and carbohydrate.
According to claim 1,
The natural product blocking layer,
A composite film for a vacuum insulation panel comprising a cured product of a natural product composition including a natural product and a silane-based coupling agent.
According to claim 11,
The weight ratio of the natural product and the silane-based coupling agent is 10: 1 to 1: 10 of the composite film for a vacuum insulation panel.

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