KR20230160466A - Coating compositions for paper having oxygen barrier properties, food wrapping paper using the same and method for manufacturing the same - Google Patents

Abstract

The present invention is a coating agent for a coating layer formed on a base paper, comprising an acrylic polymer resin and polyvinyl alcohol, and the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight to 50% by weight based on dry weight. It relates to a coating composition for papermaking with oxygen barrier properties, characterized in that %:50% by weight.

Description

Coating agent for papermaking with oxygen barrier properties, food packaging paper using the same, and method of manufacturing the same

The present invention relates to a coating agent for papermaking having oxygen barrier properties, food packaging paper using the same, and a method for manufacturing the same.

Maintaining a long storage and distribution period is an important part of food packaging. Efforts to prevent the spoilage of processed foods and rancidity of oils and fats caused by gases, especially oxygen, have been continuously made in the food packaging industry.

Aluminum is used as a commercial oxygen barrier material without substitutes, and food-related companies use polyethylene (PE), polypropylene (PP), and polyvinyl chloride (PVC) to add additional functions to aluminum for product packaging. ), polyethylene terephthalate (PET), and other petroleum-based synthetic polymer resins are used in the form of a composite film.

The increase in the use of convenient and hygienic existing packaging materials has come into conflict with the value of protecting the global environment, such as concerns about marine pollution from microplastics and difficulties in resource circulation. Recently, self-reflection and demands for the development of eco-friendly substitutes have increased not only in Europe but also in Korea. It has become a global trend.

There is no coating agent on the market that exhibits air blocking performance when coated on a paper substrate and can be recycled after use.

Accordingly, the inventor of the present invention completed the present invention after a long period of research and trial and error on a coating agent for papermaking with oxygen barrier properties, food packaging paper using the same, and a method for manufacturing the same.

The purpose of the present invention is to provide a coating composition for papermaking having oxygen barrier properties.

The purpose of the present invention is to provide food packaging using a paper coating composition having oxygen barrier properties.

The purpose of the present invention is to provide a method of manufacturing food packaging using a paper coating composition having oxygen barrier properties.

Meanwhile, other unspecified purposes of the present invention will be additionally considered within the scope that can be easily inferred from the following detailed description and its effects.

According to an embodiment of the present invention, the coating agent for the coating layer formed on the base paper includes an acrylic polymer resin and polyvinyl alcohol, and the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20 based on dry weight. A coating composition for papermaking having oxygen barrier properties, characterized in that the ratio is 50% by weight: 50% by weight, is provided.

The mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight.

According to an embodiment of the present invention, base paper; and a coating layer formed on the base paper, wherein the coating layer includes an acrylic polymer resin and polyvinyl alcohol, and the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight based on dry weight. A coating composition for papermaking having oxygen barrier properties, characterized in that 50% by weight: 50% by weight, is provided.

The mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight.

The basis weight of the base paper may be 30 to 120 g/m2.

The base paper may include a mixture of softwood pulp and hardwood pulp in a weight ratio of 70:30 to 50:50.

The freeness of the base paper may be 200ml to 300ml, and the tear index of the base paper may be 15mN·m2/g or more.

The coating amount of the coating layer may be 5 to 20 g/m2.

According to an embodiment of the present invention, providing a base paper; Forming a coating layer on the base paper; and drying the coating layer, wherein the coating layer includes an acrylic polymer resin and polyvinyl alcohol, and the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight based on dry weight. A coating composition for papermaking having oxygen barrier properties, characterized in that 50% by weight: 50% by weight, is provided.

The mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight.

The basis weight of the base paper may be 30 to 120 g/m2.

The step of providing the base paper may include mixing softwood pulp and hardwood pulp at a weight ratio of 70:30 to 50:50, and refining the paper to have a freeness of 200 to 300 ml in a paper refining equipment.

The coating amount of the coating layer may be 5 to 20 g/m2.

In the drying step, the drying temperature may be 105 to 150 °C.

Food packaging using the coating agent with oxygen barrier properties according to the present invention is an eco-friendly product and has high organic recyclability when discarded.

Food packaging using the coating agent having oxygen barrier properties according to the present invention has excellent gas barrier properties (barrier properties) such as oxygen, water resistance, grease resistance, and heat sealing properties. property).

Meanwhile, it is to be added that even if the effects are not explicitly mentioned herein, the effects described in the following specification and their potential effects expected from the technical features of the present invention are treated as if described in the specification of the present invention.

Figure 1 is a diagram showing food packaging according to an embodiment of the present invention.
The attached drawings are intended as reference for understanding the technical idea of the present invention, and are not intended to limit the scope of the present invention.

In describing the present invention, if it is determined that related known functions may unnecessarily obscure the gist of the present invention as they are obvious to those skilled in the art, the detailed description thereof will be omitted.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, embodiments of the paper coating agent having oxygen barrier properties according to the present invention, the food packaging paper using the same, and the manufacturing method thereof will be described in detail with reference to the attached drawings. In the description with reference to the attached drawings, they are identical or correspond to each other. The same drawing numbers will be assigned to the components, and duplicate descriptions thereof will be omitted.

The coating agent for papermaking with oxygen barrier properties according to the present invention is a coating agent for a coating layer formed on a base paper, and may include an acrylic polymer resin and polyvinyl alcohol (polyvinylalcohol, PVOH).

As the acrylic polymer resin, pure acrylic polymer resin obtained by polymerizing acrylic monomer with a weight average molecular weight of 100,000 to 1 million can be used.

Acrylic monomers include methyl acrylate, ethyl acrylate, 2-hydroxyethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, and hydroxyl acrylate. Consists of one or more compounds selected from the group consisting of ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, cyclohexyl methacrylate, isobutyl methacrylate, acrylonitrile, methacrylic acid, and combinations thereof. You can. Preferably, the acrylic monomer may be a combination of butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, and methacrylic acid.

The reason for using acrylic resin is that it is advantageous to make a water-soluble emulsion type, and manufacturing process problems can be minimized during the repulping and papermaking processes for recycling during the typical papermaking process, and an appropriate drying process after coating. This is because the emulsion condensation coating film formed through this process exhibits water resistance and heat sealing properties.

Acrylic polymer resin is a water-dispersible type, and problems that may occur during the repulping process for recycling and papermarking process during the typical papermaking process (process water contamination, adsorption of drying drum, clogging of papermaking wire, etc.) can be minimized.

The hydrolysis degree of polyvinyl alcohol (PVOH) may be 99 mol% or more. In this case, there is the advantage of not only improved gas impermeability but also high oil resistance after forming the coating film. A representative commercial product is the EXCEVAL product from Japan's Kuraray.

Before mixing the acrylic polymer resin and polyvinyl alcohol (PVOH), the polyvinyl alcohol (PVOH) may be gelatinized in an aqueous solution at 90°C to 95°C. The concentration for gelatinization may be 3% to 25% by weight.

Polyvinyl alcohol (PVOH) can be coated or impregnated on paper alone, but the material itself has a high hygroscopicity for moisture, and the barrier property is significantly reduced by the absorbed moisture, so reinforcement of water resistance or moisture resistance is necessary.

In order to provide water resistance or moisture resistance, acrylic polymer resin and polyvinyl alcohol (PVOH) must be mixed in an appropriate mixing ratio. In other words, when mixed at an appropriate mixing ratio, the coating agent can secure water resistance while maintaining barrier properties. In addition, the heat sealing properties of acrylic resin are also maintained.

The mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 50% by weight: 50% by weight based on dry weight. That is, the weight ratio of the acrylic polymer resin to polyvinyl alcohol may be 0.25 or more and 1 or less.

If the polyvinyl alcohol (PVOH) mixing ratio is less than 20% by weight, the barrier properties may not be effectively demonstrated. In addition, if the mixing ratio exceeds 50% by weight, water resistance is significantly reduced, the viscosity of the coating composition increases, and problems such as constant control of the coating amount during the coating process may occur.

Preferably, the mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight. That is, the weight ratio of the acrylic polymer resin to polyvinyl alcohol may be 0.25 or more and 0.39 or less. When the weight ratio of acrylic polymer resin to polyvinyl alcohol is 0.25 or more and 0.39 or less, oxygen barrier properties are excellent.

A small amount of preservative, antistatic agent, antifoaming agent, thickener, slip control agent, etc. may be added to the coating agent formulated according to the above mixing criteria, depending on the application conditions of various coating processes. Additionally, all operations are performed in aqueous solution.

item Sample 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 Acrylic polymer resin (M) 85 82 80 78 75 72 70 50 PVOH(N) 15 18 20 22 25 28 30 50 Sum(M+N) 100 100 100 100 100 100 100 100 Ratio (N/M) 0.18 0.22 0.25 0.28 0.33 0.39 0.43 1.00 oxygen permeability 2.5 3.0 1.4 1.5 1.5 1.4 2.2 3.5

[Table 1] shows the oxygen permeability measured after preparing coating agents by varying the ratio of PVOH to acrylic polymer resin and manufacturing coated paper to which each coating agent was applied. M = weight% of acrylic polymer resin, N = weight% of PVOH.

The acrylic polymer resin was used as an acrylic polymer resin (product name RP100) purchased from Repaper Co., Ltd., which contains ethyl acrylate as the main ingredient. PVOH was used by purchasing P-2117 from EXCEVAL products from Kuraray, Japan. A coating color was created by mixing acrylic polymer resin and gelatinized PVOH in the ratio according to [Table 1].

The coating agent prepared by the above method was applied to the base paper. The base paper is made of bleached softwood pulp and hardwood pulp at a weight ratio of 50:50, and is refined according to the test method of TAPPI T200 using a valley beater experimental beater to 250ml CFR. ㎡ of aquatic plants were produced. For coating, 10.0 g/m2 of the coating agent prepared in Example 1 was coated on the surface of the base paper using a coating bar commonly used in paper coating experiments, based on the dry coating amount. Food packaging paper (coated paper) with a total weight of 70 g/m2 was manufactured.

Oxygen permeability was measured for the coated paper prepared above using the test method ASTM D3985, and the unit is cm3/m2/day.

Referring to [Table 1], when the ratio of the acrylic polymer resin to polyvinyl alcohol was 0.25 or more and 0.39 or less, the oxygen barrier properties were excellent.

Figure 1 is a diagram showing food packaging according to an embodiment of the present invention. Referring to Figure 1, the food packaging paper having oxygen barrier properties according to the present invention may include a base paper 100 and a coating layer 200. The coating layer 200 may be formed on the base paper 100 (on at least one side of the base paper 100). The coating layer 200 may include acrylic polymer resin and polyvinyl alcohol (PVOH).

The mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 50% by weight: 50% by weight based on dry weight. That is, the weight ratio of the acrylic polymer resin to polyvinyl alcohol may be 0.25 or more and 1 or less.

Preferably, the mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight. That is, the weight ratio of the acrylic polymer resin to polyvinyl alcohol may be 0.25 or more and 0.39 or less.

The basis weight of the base paper 100 to be used as a substrate may be 30 g/m2 to 120 g/m2. If the basis weight is lower than the suggested basis weight range, the strength is lowered and may break during continuous post-processing processes such as molding, and if it is higher, it becomes too thick and is also not suitable for the continuous production process.

The base paper 100 may be a mixture of softwood pulp and hardwood pulp. Softwood pulp can be unbleached or bleached kraft. Because it contains kraft softwood pulp, the base paper 100 can have tough characteristics and high tear strength.

In the case of bleached hardwood pulp fibers, which are mainly short fibers mainly used for printing paper, the tearing strength is low, so it is possible to mass-produce thin packaging materials with a low basis weight without tearing through a continuous process. There are limits to sealing and distributing contents such as food.

In the case of long-fiber, unbleached softwood pulp fibers, tear strength can be greatly improved through appropriate refining treatment, so strength properties comparable to those of existing plastic films can be expected. Therefore, in the present invention, base paper 100 containing softwood pulp fibers can be used.

Meanwhile, in the case of disposable convenience foods, the packaging material itself is often cooked directly in a microwave or oven, so white flexible packaging materials or containers based on bleached pulp fibers may discolor during cooking, which may reduce user favorability. may fall. In the case of paper made from unbleached pulp fibers, which are generally yellow, this discoloration problem may not occur. Therefore, in the present invention, base paper 100 containing unbleached softwood (coniferous) pulp fibers can be used.

Softwood pulp and hardwood pulp can be mixed in a weight ratio of 70:30 to 50:50. For example, the mixing ratio of bleached softwood pulp and hardwood pulp may be 70:30 by weight.

After softwood pulp and hardwood pulp are mixed, they can be refined in a paper refiner. The freeness (Canadian Standard Freeness, CSF) of the raw paper 100 obtained through refining may be 200 ml to 300 ml. The tear strength is high in the optimal freeness range, and the base paper 100 of the food packaging paper according to the present invention may have the highest tear strength or tear index in the above-mentioned freeness range. Paper with a strength of 15 mN·㎡/g or more can be manufactured by expressing the tear strength as a tear index divided by the basis weight.

In the case of flexible packaging paper using paper with a low basis weight, high tear strength is important in the typical post-processing process, and it can function as a base paper (100) at a tear index or higher than the above-mentioned tear index.

In addition, the base paper 100 should not use a fluorescent whitening agent that is safe for food contact, and should not contain recycled pulp if possible.

The coating layer 200 can be manufactured by forming the above-described coating agent on at least one side of the base paper 100. The coating layer 200 may have a coating amount of 5.0 g/m2 to 20.0 g/m2 based on solid content.

If the coating amount is less than 5.0g/㎡ based on solid content, the basic barrier performance may not be achieved due to the thin thickness of the layer after drying. If the coating amount is more than 20.0 g/㎡ based on solid content, commercial competitiveness is low due to high cost, and problems with coating surface stickiness may occur.

The method for manufacturing food packaging with oxygen barrier properties according to the present invention includes the steps of providing base paper 100, forming a coating layer 200, and drying the coating layer 200. The coating layer 200 may include acrylic polymer resin and polyvinyl alcohol.

The mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 50% by weight: 50% by weight based on dry weight. That is, the weight ratio of the acrylic polymer resin to polyvinyl alcohol may be 0.25 or more and 1 or less.

Preferably, the mixing ratio of the acrylic polymer resin and polyvinyl alcohol may be 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight. That is, the weight ratio of the acrylic polymer resin to polyvinyl alcohol may be 0.25 or more and 0.39 or less.

In the step of providing the base paper 100, bleached softwood pulp and hardwood pulp are mixed at a weight ratio of 70:30 to 50:50, and Canadian Standard Freeness (CSF) is applied in a paper refiner. It is refined alone or mixed to make 200ml to 300ml.

Before mixing the acrylic polymer resin and polyvinyl alcohol (PVOH), the polyvinyl alcohol (PVOH) may be gelatinized in an aqueous solution at 90°C to 95°C. The concentration for gelatinization may be 3% to 25% by weight.

The step of forming the coating layer 200 is a step of forming the coating layer 200 on at least one side of the base paper 100. The coating agent composition of the coating layer 200 is as described above.

Equipment for coating can be any paper coating method, including impregnation, but preferably a rod coater and an air knife coater can be used.

Coating equipment for coating can be used as either a typical on-machine coater or an off-machine coater in the paper industry. In addition, roll coater, blade coater, rod coater, air knife coater, short dwell coater that can effectively control low coating amounts, Any method selected from bill balde coater and gate roll coater can be applied. Additionally, the same coating effect can be achieved with gravure type printing equipment.

The coating amount of the coating layer 200 may be 5 to 20 g/m2.

In the drying step, the drying temperature may be 105 to 150 °C. The optimal drying temperature condition for performance after coating is preferably 105°C to 150°C.

Drying may not occur properly at temperatures lower than the suggested conditions, which may cause blocking problems in the manufactured coated paper winding roll. Incomplete drying may result in poor barrier performance due to insufficient close adhesion between coating emulsion particles. . At temperatures higher than the suggested conditions, cracks occur on the coating surface due to overdrying, which ultimately reduces the barrier property.

After going through the above process, calendaring can be additionally performed to make the coated paper more robust and improve surface smoothness. Implementation of this process is particularly effective in improving oxygen barrier properties by further reducing the pores of the paper and increasing the density of the coating layer 200.

Through the above process, food packaging paper (coated paper) that has barrier properties and heat sealing properties, as well as greatly improved water resistance and oil resistance, can be obtained. In addition, the food packaging paper according to the present invention can be used again as a pulp raw material when recovered after use and re-introduced into the papermaking process, so it can be implemented as an eco-friendly food packaging paper.

The barrier property of the paper manufactured through the present invention is tested by the oxygen permeability measurement method (ASTM D3985) and achieves less than 5.0 cc/m2/day, and the oil resistance is tested by the American Paper and Pulp Technology Association's test method (TAPPI T559cm-02). It achieves Kit # 7 or higher, and water resistance is 12.0 g/㎡ (30 minutes - 95℃ or less) by applying the Cobb size method of TAPPI T441.

In terms of eco-friendliness, paper made using the manufacturing method of the above invention has been evaluated for material recycling (KS T ISO 18604-2018) and organic recycling (KS T ISO 10606-2018) based on the KS standards for environment and packaging established by the Korean Ministry of Environment. You can. Regarding material recyclability, a specific method is the Somerville-type fiber screening test of the TAPPI T275 standard test method to confirm a reusable fiber yield (accept ratio) of more than 97%. Organic recyclability can be confirmed as industrial compostable by more than 90% using the European standard EN13432 method.

The food packaging paper according to the present invention complies with the test standards for processed paper materials in the standards and specifications for apparatus and containers and packaging of the Ministry of Food Safety and Security, and can be safely used as food packaging paper.

<Example 1> Coating agent (same as Sample 1-5 in [Table 1])

The acrylic polymer resin was used as an acrylic polymer resin (product name RP100) purchased from Repaper Co., Ltd., which contains ethyl acrylate as the main ingredient.

PVOH was used by purchasing P-2117 from EXCEVAL products from Kuraray, Japan. A coating color was created by mixing acrylic polymer resin and gelatinized PVOH in a ratio of 75 to 25 based on solids weight.

<Example 2> Food packaging paper (coated paper)

The base paper is made of bleached softwood pulp and hardwood pulp at a weight ratio of 50:50, and is refined according to the test method of TAPPI T200 using a valley beater experimental beater to 250ml CFR. ㎡ of aquatic plants were produced. For coating, 10.0 g/m2 of the coating agent prepared in Example 1 was coated on the surface of the base paper using a coating bar commonly used in paper coating experiments, based on the dry coating amount. Food packaging paper (coated paper) with a total weight of 70 g/m2 was manufactured.

<Example 3> Food packaging paper (coated paper)

The same conditions and method as in Example 2 were used, but the coating amount was 20.0 g/m2. Food packaging paper (coated paper) with a total weight of 80 g/m2 was manufactured.

<Example 4> Food packaging paper (coated paper)

As the base paper, 60g/m2 of glassine from Hansol Paper Co., Ltd. was used, and the coating agent prepared in Example 1 was coated through road coating in a typical papermaking coater. The concentration of the coating agent was maintained between 5% and 18%. The total coating amount was 10.0 g/㎡ based on dry solids. Food packaging paper (coated paper) with a total weight of 70 g/m2 was manufactured.

<Example 5> Food packaging paper (coated paper)

The same conditions and methods as in Example 4 were used, but the coating amount was 20.0 g/m2. Food packaging paper (coated paper) with a total weight of 80 g/m2 was manufactured.

<Comparative Example 1>

Among seasoned seaweed packaging materials commonly available on the market, a packaging material in which polyethylene and polypropylene were multilayer bonded to aluminum foil (thickness 7㎛) was used as a comparative example.

<Comparative Example 2>

Ramen bag packaging commonly available on the market was purchased and used as a comparative example.

<Comparative Example 3>

6.5oz paper cup paper (basis weight 190 g/m2), commonly available on the market, was purchased and used as a comparative example. The paper cup paper was measured to be laminated with a polyethylene (PE) film with a thickness of approximately 11㎛.

Materials prepared through Examples and Comparative Examples were tested for physical properties under the same conditions, and the results are summarized in [Table 2] below.

item Example Comparative example 2 3 4 5 One 2 3 Oxygen permeability (1) 1.5 1.5 1.4 1.6 4.5 5.0 17000 Water resistance (2) 25 12 26 20 3 7 55 Oil resistance (3) 8 10 7 10 12 12 11 Tear strength (4) 19 20 21 18 17 16 7 Material recyclability (5) 97 97 99 98 Not measurable Organic recyclability (6) 90 90 90 90 0 0 0 unit (1) Oxygen permeability (test method: ASTM D3985): ㎤/㎡/day
(2) Cobb size chart (Test method: TAPPI T441): g/㎡, (test in 95℃ water for 30 minutes)
(3) 3M Kit No. (Test Method: TAPPI T559): Numbers 1 to 12
(4) Tear Index (Test method: TAPPI T 414): mN·㎡/g
(5) Pulp fiber acceptability (test method: TAPPI T275): %
(6) Industrial compostability (Test method: EN13432 (2000): %

From the results in [Table 2], the eco-friendly food packaging produced by the method of Examples 2 to 5 according to the present invention has excellent oxygen barrier properties and tear strength corresponding to the existing composite flexible packaging materials corresponding to Comparative Examples 1 to 3. It has excellent oil resistance and water resistance. In particular, it was confirmed to be an excellent material as an environmental substitute due to its excellent material recyclability and organic recyclability.

The scope of protection of the present invention is not limited to the description and expression of the embodiments explicitly described above. In addition, it is added once again that the scope of protection of the present invention may not be limited due to changes or substitutions that are obvious in the technical field to which the present invention pertains.

100: base
200: coating layer

Claims (14)

As a coating agent for the coating layer formed on the base paper,
Contains acrylic polymer resin and polyvinyl alcohol,
Characterized in that the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight to 50% by weight: 50% by weight based on dry weight.
A coating composition for papermaking with oxygen barrier properties. According to paragraph 2,
Characterized in that the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight.
A coating composition for papermaking with oxygen barrier properties. original paper; and
It includes a coating layer formed on the base paper,
The coating layer is,
Contains acrylic polymer resin and polyvinyl alcohol,
Characterized in that the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight.
Food packaging paper with oxygen barrier properties. According to paragraph 3,
Characterized in that the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight.
Food packaging paper with oxygen barrier properties. According to paragraph 3,
Characterized in that the basis weight of the base paper is 30 to 120 g/m2,
Food packaging paper with oxygen barrier properties. According to paragraph 3,
The base paper is characterized in that it contains a mixture of softwood pulp and hardwood pulp in a weight ratio of 70:30 to 50:50.
Food packaging paper with oxygen barrier properties. According to paragraph 3,
The freeness of the base paper is 200ml to 300ml,
Characterized in that the tear index of the base paper is 15 mN·m2/g or more,
Food packaging paper with oxygen barrier properties. According to paragraph 3,
Characterized in that the coating amount of the coating layer is 5 to 20 g/m2,
Food packaging paper with oxygen barrier properties. providing base paper;
Forming a coating layer on the base paper; and
Comprising the step of drying the coating layer,
The coating layer is,
Contains acrylic polymer resin and polyvinyl alcohol,
Characterized in that the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight to 50% by weight: 50% by weight based on dry weight.
Method for manufacturing food packaging with oxygen barrier properties. According to clause 9,
Characterized in that the mixing ratio of the acrylic polymer resin and polyvinyl alcohol is 80% by weight: 20% by weight to 72% by weight: 28% by weight based on dry weight.
Method for manufacturing food packaging with oxygen barrier properties. According to clause 9,
Characterized in that the basis weight of the base paper is 30 to 120 g/m2,
Method for manufacturing food packaging with oxygen barrier properties. According to clause 9,
The step of providing the base paper is,
Softwood pulp and hardwood pulp are mixed at a weight ratio of 70:30 to 50:50,
Characterized in that it includes refining the freeness to 200 to 300 ml in a paper refining facility.
Method for manufacturing food packaging with oxygen barrier properties. According to clause 9,
Characterized in that the coating amount of the coating layer is 5 to 20 g/m2,
Method for manufacturing food packaging with oxygen barrier properties. According to clause 9,
Characterized in that the drying temperature in the drying step is 105 to 150 ° C.
Method for manufacturing food packaging with oxygen barrier properties.