KR100990529B1 - Coating for paper, paper product, and process for producing paper product - Google Patents

Abstract

PURPOSE: Paint for paper, paper product and a method for manufacturing the paper product is provided to use fluid paraffin, sucrose fatty acid ester jointly, thereby giving the paper an excellent water resistance. CONSTITUTION: Paints for paper is spread on the paper. The paint for the paper includes fluid paraffin, sucrose fatty acid ester, water-soluble resin. By the water-soluble resin, the paint is uniformly spread on the surface of the paper. The fluid paraffin give water-proofing and oil resistance to the paper product. The sucrose fatty acid ester improves the dispersibility of the fluid paraffin. The sucrose fatty acid ester has HLB value lower than six.

Description

COATING FOR PAPER, PAPER PRODUCT, AND PROCESS FOR PRODUCING PAPER PRODUCT}

TECHNICAL FIELD This invention relates to the coating material for paper, paper products, and the manufacturing method of paper products.

Crustaceans such as crabs and shrimps are commonly frozen after they have been sufficiently wetted with water in order to suppress discoloration called a freezer burn. For this reason, since sufficient water resistance is required for the container for freezing a shellfish, the container made from foamed styrol has been used conventionally (for example, refer patent document 1).

However, since the container made of foamed styrol cannot be folded and transported, the transportation cost is high and the waste plastic waste must be disposed of as plastic waste, and thus, the disposal cost and the cost of reuse are also high. In addition, when it is desired to display certain information (for example, the contents of crab or shrimp contents) on the container, it is technically difficult to perform a clear print on the surface of the foamed styrol, so that the contents of the foamed styrole container are clearly printed. It is necessary to change to the paper container (for example, the paper container for store sales) etc. which were implemented.

Japanese Patent Publication No. 1995-10179

From this situation, it is desired to construct a container for paper to replace the container made of foamed styrol, but paper products have a problem of low water resistance.

An object of the present invention is to provide a coating material for paper capable of improving the water resistance of a paper product, a paper product excellent in water resistance, a paper packaging container, and a manufacturing method of the paper product.

MEANS TO SOLVE THE PROBLEM The present inventors discovered that the coating material of the emulsion state fully disperse | distributed to the water-soluble resin is obtained by using a liquid paraffin and sucrose fatty acid ester together as a component of a coating, and it can complete | finish this invention by providing excellent water resistance to paper. It came to the following. The present invention specifically provides the following.

(1) Paint for paper containing liquid paraffin, sucrose fatty acid ester, and water-soluble resin, and apply | coating to the surface of paper.

(2) The paint for paper according to (1), wherein the sucrose fatty acid ester has an HLB value of 6 or less.

(3) The coating material for paper as described in (1) or (2) whose solid content of the said liquid paraffin is 5 mass% or more and 50 mass% or less with respect to solid content of the said water-soluble resin.

(4) To any one of (1) to (3), which further contains shellac resin or vinyl acetate resin having a solid content of 5% by mass to 50% by mass relative to the total mass of the paint for paper. Paint for paper described.

(5) The paint for paper according to any one of (1) to (4), further comprising silver (Ag) zeolite in an amount of 2% by mass to 15% by mass with respect to the total mass of the paper coating for paper.

(6) The coating material for paper as described in (5) which further contains the dispersing agent containing the compound represented by following formula (1).

Wherein R ³ and R ⁶ are methyl or ethyl groups which may be the same or different, R ⁴ and R ⁵ are straight or branched alkyl groups which may be the same or different, and m and n may be the same or different It is a natural number of 100 or less.)

(7) The coating material for paper as described in (6) whose m or n in General formula (1) is four or more.

(8) A paper product, wherein the coating material for paper according to any one of (1) to (7) is applied to the surface of the paper.

(9) The paper product according to (8), wherein the crease is formed.

(10) A paper packaging container formed of the paper product according to (8) or (9).

(11) A paper packaging container formed from the paper product according to (9), which is bent along the folds.

(12) The paper packaging container according to (10) or (11), which is used for packaging food.

(13) As a manufacturing method of a paper product,

A manufacturing method comprising the coating step of applying the coating material for paper according to any one of (1) to (7), and the curing step of curing the coating material for paper.

(14) The manufacturing method according to (13), further comprising a step of forming a crease on the paper after the paper coating is cured.

According to the present invention, by using together liquid paraffin and sucrose fatty acid ester as components of the paint, an emulsion paint sufficiently dispersed in a water-soluble resin can be obtained, and excellent water resistance can be imparted to paper.

EMBODIMENT OF THE INVENTION Hereinafter, although embodiment of this invention is described, this invention is not limited to this.

The paint for paper according to the present invention contains a liquid paraffin, sucrose fatty acid ester, and a water-soluble resin, and is applied to the surface of paper. Since the liquid paraffin having water resistance and oil resistance is sufficiently mixed and dispersed with the water-soluble resin by the action of the sucrose fatty acid ester, the coating material for paper according to the present invention can impart excellent water resistance and oil resistance to the paper.

The water-soluble resin may be a polyvinyl alcohol resin, an acrylic resin, an epoxy resin, a vinyl acetate resin, a water-soluble varnish or the like conventionally used in paints. Since these water-soluble resins have predetermined viscosity, viscosity is imparted to the coating material, so that the water-soluble resin is easily wetted by a printing roll of a printing machine, for example. Thereby, since a coating material is apply | coated uniformly to the surface of paper, water resistance etc. can be fully provided to paper. On the other hand, although solid content content of water-soluble resin is not specifically limited, It is good in about 3 mass%-about 50 mass% with respect to the whole coating material for paper.

Liquid paraffins impart water resistance and oil resistance to paper products. Although content of a liquid paraffin is not specifically limited, When too small, water resistance and oil resistance are hardly provided enough, When too large, it is difficult to form the film | membrane which consists of a paint in paper products. Therefore, it is preferable that the minimum of content of a liquid paraffin is 1 mass% with respect to solid content of all resin, ie, a water-soluble resin, and the shellac resin or vinyl acetate resin, when it contains, More preferably, it is 5 mass% Most preferably, it is 10 mass%. It is preferable that the upper limit of solid content of a liquid paraffin is 50 mass% with respect to solid content of all resin, More preferably, it is 45 mass%, Most preferably, it is 42 mass%.

Although it does not specifically limit as a liquid paraffin, One or more types, such as a normal paraffin, an isoparaffin, a cycloparaffin, have a viscosity of 15-88 mm <^2> / S at 37.8 degreeC. Thereby, viscosity is provided to a coating material, for example, it becomes easy to get wet on the printing roll of a printing press, and since a coating material is apply | coated uniformly to the surface of paper, water resistance etc. can be fully provided to paper.

Here, the liquid paraffin has very low compatibility with the water-soluble resin and has a property that is hardly dispersed in the water-soluble resin. Therefore, in order to use together with the water-soluble resin, it is necessary to improve the dispersibility in the water-soluble resin. Therefore, since the coating material for paper which concerns on this invention contains a sucrose fatty acid ester further and this improves the dispersibility to a water-soluble resin of a liquid paraffin, water resistance etc. can be fully provided to paper.

Mixing common surfactants with liquid paraffin (usually by agitation at rotation speeds above about 10000 rpm using a homogenizer) creates a large amount of foam, which can cause leakage to the outside from the stirring device. Therefore, it is essential to use an antifoaming agent together. However, since sucrose fatty acid ester is highly suppressed foaming even when mixed with liquid paraffin, it is possible to reduce the amount of antifoaming agent (do not need to use antifoaming agent), which can be expected to reduce the manufacturing cost of paper coating material and improve safety. have. Moreover, since sucrose fatty acid ester itself is excellent in safety, it is especially advantageous when manufacturing the paper packaging container which wraps food.

Specific examples of sucrose fatty acid ester include sucrose dioleic acid ester, sucrose distearic acid ester, sucrose dipalmitic acid ester, sucrose dimyritic acid ester, sucrose dilauric acid ester, sucrose monolauric acid ester, sucrose monooleic acid ester, sucrose monostearic acid ester, Sucrose monopalmitic acid ester, sucrose monomyritic acid ester, sucrose monolauric acid ester, etc. are mentioned, These can be used individually by 1 type or in combination of 2 or more types.

The sucrose fatty acid ester is different depending on the characteristics of the liquid paraffin to be used. However, the sucrose fatty acid ester can preferably have a HLB value of 6 or less from the viewpoint of further improving the dispersibility of the liquid paraffin. Examples of such sucrose fatty acid esters include those in which 2 to 5 hydroxyl groups in sucrose are esterified with fatty acids. The content of the sucrose fatty acid ester may be appropriately set depending on the characteristics of the sucrose fatty acid ester to be used and the liquid paraffin, but is preferably 0.3% by mass or more and 1.5% by mass or less with respect to the solid content of the liquid paraffin.

Although the detail of a procedure is mentioned later, the paper product in which the coating film was formed in the paper surface can be manufactured by apply | coating and hardening the coating material for paper containing said component on paper. Since such paper products are excellent in water resistance, they are useful as materials for packaging containers made of paper. However, in order to manufacture packaging containers from paper products, it is common to form molds that form folds (usually plural). to be. However, when a crease is formed, a crack occurs in a coating film, and there exists a problem that water resistance etc. fall easily.

Therefore, it is preferable that the coating material for paper which concerns on this invention further contains the shellac resin or vinyl acetate resin of solid content of 5 mass% or more and 50 mass% or less with respect to the total mass of paper coating material. Thereby, since formation of the crack by mold formation is suppressed, the paper packaging container which is more excellent in water resistance etc. can be manufactured. As for the minimum of solid content of shellac resin or vinyl acetate resin, it is more preferable that it is 20 mass% with respect to the total mass of paper coating material, and it is more preferable that an upper limit is 45 mass% with respect to the total mass of paper coating material.

Shellac resin is obtained by refining resin produced in the body by lac shellfish in Thailand and India, and its safety is also recognized by JECFA, FDA, EU, etc. In addition to showing guidelines for the handling of shellac to be used, both the "Ames test" and "Bivariate Protozoan Tests for Mammalian Cultured Cells" of Food Additives by Ministry of Health, Welfare and Welfare (Dec. 1980). The result was negative. Since safety is established in this way, it is used frequently conventionally (the Nippon Shellac Industrial Co., Ltd., lock glaze catalog page 1).

It is preferable that the paint for papers further contains silver zeolite of the quantity of 2 mass% or more and 15 mass% or less with respect to the total mass of paper paint. Thereby, the curvature of the paper product at the time of drying can be suppressed, and also antibacterial property can be provided to a paper safely. For example, "zeomic" (manufactured by Cinnanen Zeomic Co., Ltd.), which is a kind of silver zeolite, is applied to the US Food and Drug Administration (FDA) as a food contact substance notification (FCN000047), and can be adapted to all food packaging resins. There is a track record to say. It is more preferable that the minimum of content of silver zeolite is 5 mass% with respect to the total mass of the coating material for paper, and, as for an upper limit, it is more preferable that it is 10 mass% with respect to the total mass of paper coating material.

However, if silver zeolite is used, the paint may gel or solidify in a short time due to the catalytic action of silver ions, and the operability may deteriorate. Therefore, it is necessary to constantly flow the paint or to prepare and fix the paint frequently. The manufacturing cost is high. Therefore, it is preferable that the coating material for papers further contains the dispersing agent represented by General formula (1).

[Formula 1]

Wherein R ³ and R ⁶ are methyl or ethyl groups which may be the same or different, R ⁴ and R ⁵ are straight or branched alkyl groups which may be the same or different, and m and n may be the same or different It is a natural number of 100 or less.)

A complex is formed from the polyethyleneglycol structure in the molecule | numerator of this dispersing agent, and silver ions in silver zeolite. Thereby, in the state disperse | distributed to the liquid, the resin hardening effect which silver ion has becomes weak. Moreover, a propylene glycol group acts as a hydrophilic group, and the water dispersibility of silver zeolite itself improves. Therefore, since the lifetime of the coating material for papers becomes longer, a manufacturing cost can be reduced. In addition, since there is no need to provide a mechanism such as a circulation device for flowing the paint, a conventional printing press can be used.

In addition, if the surface of the paper becomes hydrophobic when the printing process is performed with ink or the like, the wettability of the water-based paint to the paper surface is reduced, whereby the water-based paint is not uniformly applied to the paper surface, thereby forming a uniform coating film. There is concern that it will be difficult to do. On the other hand, if only the wettability to the hydrophobic surface is pursued, the dispersibility of the silver zeolite in the aqueous system is lowered, which may make it difficult to form a homogeneous coating film. However, since the dispersing agent represented by the formula (1) has a polyethylene glycol structure and an acetylene glycol structure in the molecule, the compatibility of the water and the hydrophobic paper surface is improved by the polyethylene glycol structure, so that the water-based paint on the hydrophobic paper surface Can improve the wettability. Moreover, dispersibility to water of silver zeolite improves by the acetylene glycol structure. Thereby, even if a paper surface is hydrophobic, a uniform and homogeneous coating film can be formed.

On the other hand, if m or n in the general formula (1) is too small, the compatibility between the water and the hydrophobic paper surface is not sufficiently improved, so that the wettability of the water-based coating on the hydrophobic paper surface may not be sufficiently improved. do. Therefore, it is preferable that m or n is four or more. Thereby, the wettability of the water-based paint on the hydrophobic paper surface can be sufficiently improved, and a more uniform coating film can be formed.

When the addition amount of low boiling alcohols, such as ethanol, is changed, the viscosity of paper coating materials will increase and decrease. Therefore, by setting the addition amount of ethanol suitably, the coating material for paper which has a desired viscosity can be manufactured, and a uniform amount of coating material can be easily printed on paper. In addition, since low boiling point alcohols, such as ethanol, are dried in a short time after application | coating, the flipping of paper products etc. by long time drying can be suppressed.

Moreover, when a dispersion medium remains in the paper product to which the coating material for paper was apply | coated, it is feared to impair the characteristic (particularly the taste and aroma of food) of a packaging object. However, according to the low boiling point alcohols, such as ethanol, since it is quick-drying and there is no toxicity to a human body, remaining in a paper product can be suppressed and safety can be improved.

In addition, what is necessary is just to use low boiling point alcohols, such as ethanol, as an addition amount used as a solvent of shellac resin, and to be 25-50% of resin.

The coating material for paper which concerns on this invention containing the above components etc. can be manufactured, for example by the following method. First, the liquid paraffin is mixed with water, and the mixture is added and mixed with sucrose fatty acid ester to obtain an emulsion (usually by stirring at a rotation speed of about 10000 to 20000 rpm or more using a homogenizer). This emulsion is mixed with a solution such as a water-soluble resin (preferably known by stirring), and each component is dispersed to prepare a paint for paper.

The "paper coating" used in this specification can be applied to all uses for which antimicrobial activity is required, especially a product in which direct or indirect contact with the human body is expected. Specifically, a packaging paper (especially food) represented by corrugated cardboard or thick paper, a building-related wall material, a flooring material, etc. are mentioned.

The present invention includes a paper product in which the above paint for paper is applied to the surface of paper. Here, the "application" is not specifically limited as long as an antimicrobial effect is provided to the surface of paper. For example, it is good for impregnation, transfer by a roll for printing, spraying by spray, and the like. Moreover, as a "paper", a coated card paper, a Japanese paper, a nonwoven fabric, a corrugated cardboard, etc. are mentioned.

The paper product which concerns on this invention is useful as raw materials, such as a paper packaging container. When using as a raw material, such as a paper packaging container, it is preferable that a crease is formed in a paper product. Thereby, it is easy to bend a paper product according to a crease, and a packaging container can be manufactured easily.

The arrangement of the folds may be appropriately selected depending on the dimensions of the packaging container to be manufactured. The number of fold marks is not particularly limited, and may be one or plural. The fold marks may be continuous or may be interrupted.

The paper product according to the present invention is produced by a manufacturing method comprising a coating step of applying a coating material for paper to a paper surface and a curing step of curing the coating material for paper.

What is necessary is just to apply the paper coating material by a conventionally well-known method, for example, what is necessary is just to transfer the paper coating material which adhered to the roll surface to the paper surface which contacted the printing roll. According to this method, since the paper coating is economical because it is used without waste, and the paper coating is attached to a flat surface, the paper coating is transferred to the entire surface in contact with the roll. Therefore, water resistance etc. can be improved more. Here, the "flat surface" refers to the surface on which the unevenness | corrugation for printing is not performed. In addition, although the method of "contacting" is not specifically limited, For example, it is good as the system which lets paper pass while crimping | bonding to a printing roll.

Hardening of the coating material for paper may be performed by various conventionally well-known methods, such as hot air drying and active energy ray irradiation. Among these, active energy ray (for example, far-infrared) irradiation is preferable at the point which can suppress the damage of a paper product by heat.

On the other hand, a letter, a pattern, and a color can also be printed on the paper surface. As printing contents, the information of the content to be packaged is mentioned, for example, The pattern of a food to be packaged, a brand name, a production place, a distributor, etc. are mentioned. Although printing may be performed before application | coating so that the characteristic (especially antimicrobial property) of a coating film may be exhibited without covering a coating film, it is not limited to this and may be performed after hardening of a coating material. In either aspect, printing on paper can be facilitated unlike printing on foamed styrol.

Moreover, this invention includes the paper packaging container formed from the above paper product. The "paper packaging container" may be any shape such as a box shape or a bag shape. On the other hand, disassembling (for example, returning a part or all of the bending) of the paper packaging container to return to the paper product, and to reuse the paper product to produce a paper packaging container of the paper packaging container according to the present invention Corresponds to the manufacture.

Example

&Lt; Example 1 >

Distilled water and liquid paraffin were mixed at a mass ratio of 1: 1, and thereafter, sucrose fatty acid ester "F-20W" (manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd .; HLB value is 6) was added in an amount of 0.35% by mass with respect to the mixed solution. A liquid paraffin wax emulsion (hereinafter referred to as an emulsion) was obtained by stirring over 45 minutes at a rate of 20,000 revolutions per minute at room temperature using a moisturizer. Next, polyvinyl alcohol resin (10% aqueous solution), shellac resin (50% ethanol solution), and the emulsion were added at a ratio of 10: 10: 5 by mass, respectively, followed by stirring and dispersing the mixture uniformly using a conventional stirring method. The paint used was manufactured.

As a printing roll of the gravure printing machine, using the flat printing surface roll, the said paint for paper was affixed on the roll surface, and it was transferred to the paper surface. Thereafter, the paper was placed in an atmosphere at 120 ° C. for 3 seconds, and then a paper product was produced by blowing air over 7 seconds.

<Example 2>

Except that the acrylic resin varnish `` F-68 '' (manufactured by T & K Tocker, 40% resin component), shellac resin (50% ethanol solution), and the emulsion obtained in Example 1 were added at a mass ratio of 20: 4: 2, respectively. In the same manner as in Example 1 to prepare a coating material for paper and paper products.

<Example 3>

The polylactic acid monomer (70% aqueous solution), shellac resin (50% ethanol solution), and the emulsion obtained in Example 1 were added in the same order as in Example 1 except that the emulsion was added in a ratio of 20: 4: 2. Used paints and paper products were prepared.

<Example 4>

The procedure was the same as in Example 1 except that the vinyl alcohol resin (10% aqueous solution), the vinyl acetate emulsion (50% dispersion), and the emulsion obtained in Example 1 were each added in a ratio of 50: 15: 5 by mass. Paper coatings and paper products were manufactured.

<Example 5>

The points obtained by adding the acrylic resin varnish `` F-68 '' (manufactured by T & K Torker Co., Resin Component 40%), vinyl acetate emulsion (50% dispersion), and the emulsion obtained in Example 1 at a mass ratio of 30:70:30 Except for the production of paint and paper products for paper in the same procedure as in Example 1.

<Example 6>

Polylactic acid monomer (70% aqueous solution), vinyl acetate emulsion (50% dispersion), and the emulsion obtained in Example 1 were added in the same order as in Example 1 except that they were added at a mass ratio of 10:25:10. Paper coatings and paper products were manufactured.

[Water resistance evaluation]

1.5 microliters of water droplets were dripped at the paper surface of the paper products manufactured in Examples 1-6, and the contact angle of the droplet was measured 5 minutes later. The results are shown in Table 1.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Contact angle
(°) 77 85 80 79 86 80

As shown in Table 1, it was found that any of the paper products of Examples 1 to 6 had a large contact angle between the droplets and excellent water resistance.

In addition, when the droplets were held on the paper products prepared in Examples 1 to 6, the infiltration of the droplets was not observed even after 1 hour or more in the paper products of Examples 2 and 5. In the paper products of Examples 1, 3, 4 and 6, a slight degree of infiltration of the droplets was observed after about 30 minutes, but the droplets were still present on the paper surface even after 1 hour or more.

[Oil resistance evaluation]

The droplet of 10 microliters of olive oil was dripped at the paper surface of the paper products manufactured in Examples 1-6, and the time until the droplet penetrates paper was measured. In addition, the paper which did not apply the coating material was used as a control.

In contrast, in the paper products of Examples 1-6, droplets were still present on the paper surface, in contrast to the droplets penetrating the paper within 10 seconds and not present on the paper surface. By this, it was found that the paper products of Examples 1 to 6 had excellent oil resistance.

[Crack evaluation]

400 g / cm of a metal plate and a concave shape in the state which sandwiched the paper product manufactured in Examples 1-6 between the convex part of the metal plate of thickness 0.9mm, and the metal concave shape of the groove diameter of 2 mm which is symmetrical with this convex part. By pressing at the press pressure of ² , the crease was formed. The paper product was bent to 90 ° according to the folds, molded into a box, 1 mL of water was added dropwise to the bent portion, and left to stand for 1 hour, after which water permeation was observed. In addition, the paper which did not apply the coating material was used as a control.

In contrast, the water penetrated into the paper within 5 seconds after the dropping, and the strength of the paper was significantly lowered. As a result, the shape of the box could not be maintained. In contrast, in the paper products of Examples 1 to 3, water seeping was observed, but the shape of the box was maintained. In the paper products of Examples 4 and 6, the seepage of water was slightly observed, but the shape of the box was maintained. In the paper product of Example 5, no water seeping was observed, and the strength and shape of the box were almost completely maintained.

<Examples 7 to 12>

43.8% with respect to the mass of the paint prepared in Examples 1 to 6 by mixing an aqueous solution obtained by mixing silver zeolite, water, and polyacetylene glycol ("Suspinol 485" manufactured by Nisshin Chemical Co., Ltd.) at a mass ratio of 15.5: 84.2: 0.31. The paint for paper was prepared by mixing with paint in the quantity of. Examples 7-12 are each using Examples 1-6 sequentially.

Antimicrobial Evaluation

The paper products manufactured in Examples 7 to 12 were evaluated for antimicrobial properties based on "JIS Z2801". Specifically, first, each of the paper products and the untreated papers of Examples 7 to 12 was thermally sterilized (121 ° C. for 15 minutes), and then a predetermined amount of yellow was applied to one side of each paper (4 cm × 4 cm). Staphylococcus or E. coli were inoculated. Then, after hold | maintaining at 35 degreeC for 24 hours, the number of bacteria on each paper was measured. The results are shown in Tables 2-3.

Example
1 to 6
(Average) Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 yellow
Grape
coccus
Early
Bacteria 2.1 × 10 ⁵ 1.9 × 10 ⁵ 2.0 × 10 ⁵ 2.3 × 10 ⁵ 2.0 × 10 ⁵ 2.3 × 10 ⁵ 2.1 × 10 ⁵ exam
after
Bacteria 1.6 × 10 ⁶ Not detected Not detected Not detected Not detected Not detected Not detected

Example
1 to 6
(Average) Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Escherichia coli
Early
Bacteria 2.4 × 10 ⁵ 2.1 × 10 ⁵ 2.5 × 10 ⁵ 2.1 × 10 ⁵ 1.7 × 10 ⁵ 2.7 × 10 ⁵ 2.4 × 10 ⁵ exam
after
Bacteria 3.0 × 10 ⁷ Not detected Not detected Not detected Not detected Not detected Not detected

As shown in Tables 2 to 3, in the paper products of Examples 7 to 12, unlike the paper products of Examples 1 to 6, both Staphylococcus aureus and E. coli were extinct. Thereby, it was confirmed that excellent antibacterial property can be provided to a paper product by using silver zeolite in the paper coating material which concerns on this invention.

[Stress Resistance Evaluation]

The coated cardboard (about 0.3 mm thick) was cut into 5 cm x 10 cm, and on one surface thereof, the coating material for paper prepared in Examples 4 to 6 and 10 to 12 was applied in an amount of 20 g / m ² , and naturally dried. Done. The warpage state of the paper after 16 hours was measured. Table 4 shows the differences in warpage between the paper products.

Example 4-Example 10 Example 5-Example 11 Example 6-Example 12 Difference of warpage (mm) 2.59 0.22 1.67

As shown in Table 4, in the paper products of Examples 10-12, the curvature was smaller than the paper products of Examples 4-6, and it turned out that curvature can be suppressed by addition of silver zeolite. On the other hand, the difference in the warpage of Examples 4 and 10, 6, and 12 is greater than the difference in the warpage of Examples 5 and 11 due to the kind of water-soluble resin or the hardness of the coating film (the coating film containing polyvinyl alcohol is , Softer than a coating film containing an acrylic resin and vulnerable to stress).

Claims (14)

A paint for paper containing liquid paraffin, sucrose fatty acid ester, and a water-soluble resin, which is applied to the surface of paper. The method of claim 1,
The paint for paper, wherein the sucrose fatty acid ester has an HLB value of 6 or less. The method of claim 1,
Solid content of the said liquid paraffin is 5 mass% or more and 50 mass% or less with respect to solid content of the said water-soluble resin. The method of claim 1,
The coating material for paper which further contains the shellac resin or vinyl acetate resin of 5 mass% or more and 50 mass% or less of solid content content with respect to the total mass of the said paper coating material. The method of claim 1,
The coating material for paper which further contains silver zeolite of the quantity of 2 mass% or more and 15 mass% or less with respect to the total mass of the said coating material for paper. The method of claim 5, wherein
The paint for papers which further contains the dispersing agent containing the compound represented by following formula (1).
[Formula 1]

Wherein R ³ and R ⁶ are methyl or ethyl groups which may be the same or different, R ⁴ and R ⁵ are straight or branched alkyl groups which may be the same or different, and m and n may be the same or different It is a natural number of 100 or less.) The method according to claim 6,
Paint for paper whose m or n in General formula (1) is four or more. The paper product in which the coating material for paper of any one of Claims 1-7 was apply | coated to the surface of paper. The method of claim 8,
Paper product with creases. A paper packaging container formed of the paper product according to claim 8. A paper packaging container formed from the paper product according to claim 9, which is bent according to the folds. The method of claim 10,
Paper packaging container used for food packaging. A method for producing a paper product, comprising a coating step of applying the paper coating material according to any one of claims 1 to 7 to a surface of the paper, and a curing step of curing the paper coating material. The method of claim 13,
A method for producing a paper product, further comprising the step of forming a crease on the paper after the paper coating is cured.