JPH04178476A - Coating agent for preventing cargo shifting of paper container and anti-slip corrugated board case coated with the agent - Google Patents

Abstract

PURPOSE:To obtain the subject coating agent having excellent anti-slip property, abrasion resistance, etc., by mixing a self-crosslinking emulsion to a vinyl acetate copolymer emulsion protected by a polyvinyl alcohol colloid having a specific glass-transition temperature. CONSTITUTION:The objective coating agent has a pH of <=7 and a thixotropy index of 1.2-3.0 and is composed mainly of a mixture of (A) 50-100 pts.wt. of a vinyl acetate copolymer emulsion protected by a polyvinyl alcohol colloid having a glass transition temperature of -5 to +10 deg.C and (B) 0-50 pts.wt. of a self-crosslinking emulsion having a glass transition temperature of 0-30 deg.C. The vinyl acetate copolymer emulsion of the component A is preferably an ethylene-vinyl acetate copolymer emulsion wherein the sum of the vinyl acetate unit and the ethylene unit is >=50wt.% of the total resin component.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention has excellent suitability for high-speed printing with flexo printing machines, etc.
By simply coating the surface of paper containers such as paper containers such as cardboard and cartons, and paper bags such as kraft heavy goods, it is possible to prevent these paper containers from collapsing, and the effect of preventing collapsing can be maintained. The present invention relates to an anti-slip coating agent that has good properties and does not cause blocking (adhesion of cargo boxes to each other) during unpacking, and an anti-slip corrugated cardboard case that has the effect of preventing the cargo from collapsing by applying the coating agent.

[Conventional technology]

Currently, food and beverages are mostly transported in cardboard packaging, and resins, grains, etc. are often transported in kraft heavy packaging. In addition, these paper containers are usually stacked individually on pallets for storage and transportation, but the collapse of the cargo during this process has become a problem. Especially in recent years,
Mechanization has progressed due to high labor costs and labor shortages, and with the automation of packaging lines, efficiency improvements in transportation lines, and the development and speeding up of unmanned automated warehouses, not only cargo collapses, but even the slightest shift of cargo is subject to trouble. As a method to prevent these cargoes from collapsing or shifting, fixing them with wooden frames,
Mechanical methods such as binding with banding tape or covering with shrink film or sheets, methods of temporarily bonding the upper and lower containers with adhesive, and coating the surface of the container with an anti-slip coating to prevent cargo from collapsing. There are ways to do this.

Mechanical methods and adhesive methods require the work to be carried out at the same time as loading, making it difficult to work at high speeds, and unpacking is complicated. Prevention processing must be applied. Furthermore, in the case of mechanical methods, cleaning up the crates, bands, films, or sheets that are no longer needed after unpacking is a major problem. In addition, in the case of adhesive method,
Since the surface of the paper container is damaged during unpacking and adhesive remains on the surface, it is completely unsuitable for 2g containers that require aesthetic appearance.

These problems can be solved by applying a coating agent to prevent cargo from collapsing. In other words, food and beverages can be packed in slip-proof containers coated with a coating agent to prevent cargo from collapsing using flexographic printing, etc., and can be prevented from collapsing simply by stacking them, making the work fast and easy. No waste will be generated and the surface of the container will not be damaged. Furthermore, since all the containers are anti-slip treated, the effect of preventing cargo from collapsing does not deteriorate even after reloading (this is the most desirable method).

This coating agent to prevent load collapse is broadly divided into hot melt type and emulsion type, but hot melt type requires special hot melt coating equipment, and the high heat can cause warping of cardboard etc. There is a risk of burns to workers, and is it necessary to use toluene to clean the printing press?
Since H agent is used, there is a risk of fire. For this reason, there are many problems when using them for flammable paper containers, and emulsion-type coating agents are currently the main choice.

However, conventional emulsion-type coating agents are mainly based on acrylic copolymer emulsions, which utilize the adhesive properties of acrylic copolymers, and have good anti-slip properties (preventing loads from collapsing). In this case, the so-called profking phenomenon occurs, in which the bottom surface of the upper box and the top surface of the lower box of the cargo adhere to each other due to the weight of the container.

Furthermore, if a hard acrylic copolymer that does not cause blocking is used, sufficient anti-slip properties will not be obtained.

For this reason, a mixture of a soft acrylic copolymer and a hard acrylic copolymer is used, or an acrylic copolymer with a core-shell structure in which the core part is hard and the wall part is soft (Japanese Patent Application Laid-Open No. 2-34671), Blending colloidal silica into acrylic copolymer emulsion (Unexamined Japanese Patent Publication No. 2-129
No. 271) or use a composite particle emulsion of colloidal silica and acrylic copolymer (Japanese Unexamined Patent Publication No. 1-3)
08748 Publication) or blending thermoplastic hollow particles (Example 1; J 60 21419 Publication 9) 3)
Coating agents for preventing load collapse, which have both anti-slip and anti-blocking properties, have been developed by blending inorganic particles and thermoplastic hollow particles (Japanese Unexamined Patent Publication No. 1-228834). Products containing inorganic particles such as colloidal silica may damage the printing press, or may fall off due to vibration during transportation or reloading operations, reducing the anti-slip property or blocking resistance. Sexuality may decrease. In addition, since these particles are expensive, the coating agent is also expensive, and hollow particles have low abrasion resistance, so
There is a problem that the abrasion resistance of the coating film decreases. In the case of a blend of soft resin and hard resin or a core-shell structure, the anti-slip and anti-blocking properties are only intermediate between the two, but they do not provide an essential solution. Furthermore, acrylic emulsions are not satisfactory for practical use.Acrylic emulsions have the following serious drawbacks, and even if they are good experimentally, serious problems occur in actual printing lines. That is, acrylic emulsions are generally alkaline in terms of stability. On the other hand, paper containers such as cardboard boxes usually have printing indicating the food or drink being packaged. This printing is done using alkali-soluble water-based ink, and on top of this alkali-soluble water-based ink, a coating agent for preventing load collapse is applied. For this reason, if the coating agent is alkaline, it will re-dissolve the water-based ink and
Bleeding of the water-based ink and coloring of the coating agent due to the water-based ink will occur, severely impairing the appearance of the container.

Furthermore, acrylic emulsion has a low viscosity and cannot be coated in a sufficient amount to provide anti-slip properties.

For this reason, printing is performed by adding an alkali-soluble water-soluble resin as a thickener, but the viscosity of the emulsion thickened with this alkali-soluble water-soluble resin changes depending on the printing speed.
Since the amount of coating also changes, it becomes extremely difficult to control working conditions.

Therefore, there is a product based on an ethylene-vinyl acetate copolymer emulsion that has a soft and tough coating (Japanese Patent Publication No. 63-52065), but this also contains an alkali-soluble water-soluble resin. This includes the aforementioned problems of redissolving the water-based ink and controlling the amount of application.

[Problem to be solved by the invention]

The present invention was completed as a result of repeated research to solve the above-mentioned problems of the conventional technology, and includes: (1) a uniform and stable coating amount that is desirable for achieving performance during high-speed printing; ■No need to re-melt the water-based ink, ■Excellent anti-slip properties, ■Excellent anti-blocking properties, ■Good abrasion resistance and does not reduce load collapse prevention effect due to abrasion.
The purpose of the present invention is to provide a coating agent for preventing paper containers from collapsing and a non-slip corrugated cardboard case, which have the above-mentioned excellent properties.

[Means to solve the problem]

As a result of repeated research to achieve the above objective, it was found that a vinyl acetate copolymer emulsion of polyvinyl alcohol (referred to as PVA) protective colloid with a Tg (glass transition temperature) of -5 to +10°C, preferably 0 to 5°C. It was discovered that it forms a coating film that is tough, has good anti-slip properties, has good anti-blocking properties, has good high-speed printing properties, and does not dissolve water-based inks.

Unlike alkali-soluble water-soluble resins, PVA is stable on the acidic side, and not only provides an emulsion with relatively low thixotropy that has good transferability to paper containers, but also has the excellent properties of a slightly sticky resin. It provides anti-blocking properties and toughness without impairing anti-slip properties.

The vinyl acetate copolymer contains 50% by weight or more of vinyl acetate and contains monomers copolymerizable with vinyl acetate, such as ethylene, ethyl acrylate, butyl acrylate,
Acrylic ester monomers such as 2-ethylhexyl acrylate, methacrylic ester monomers such as methyl methacrylate, octyl methacrylate, and decyl methacrylate, dibutyl maleate, di(
Copolymers with monomers selected from maleate ester monomers such as (2-ethylhexyl), vinyl ester monomers such as vinyl versatate, or unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and maleic acid. It is also possible to use a vinyl acetate resin with a plasticizer added to adjust the Tg to -5 to 10°C, but from the viewpoint of the toughness and blocking resistance of the coating film, vinyl acetate units and ethylene units can be used. Ethylene-vinyl acetate (containing 50% by weight or more of the total resin components)
A copolymer emulsion (hereinafter referred to as EVA) is preferred.

Furthermore, vinyl acetate copolymer emulsions are produced by emulsion polymerization of vinyl acetate copolymer monomers in a PVA solution, rather than by adding PVA to emulsions using surfactants or other protective colloids. Colloidal vinyl acetate copolymer emulsions are desirable because they are excellent in stability (mechanical stability) during high-speed printing, transferability, and transparency and toughness of coating films. This is thought to be due to the formation of a bond (graft bond) between PVA and vinyl acetate.

From the standpoint of stability and transparency, the amount of PVA as a protective colloid should be at least 2 parts by weight based on the resin, but this is usually used in vinyl acetate copolymer emulsions of PVA protective colloids that are reprinted. This is the amount that has been Furthermore, from the viewpoint of high-speed printing performance, toughness, and water washability of the printing machine and printing plate after printing, it is desirable that the amount is 5 parts by weight or more based on the resin. If there are problems with these properties, they can be solved by adding an aqueous PVA solution and adjusting the total amount of PVA to 5 to 40 parts by weight based on the resin content. If PVA exceeds 4oTf11 parts, water resistance and blocking resistance will decrease. The degree of saponification of PVA is preferably 80 to 95%, preferably 85 to 90%. If the degree of saponification is less than 80%, water resistance and blocking resistance will deteriorate, and if it exceeds 95%, water resistance will improve, but
After addition, the transparency of the coating film of the emulsion and the fluidity of the liquid deteriorate, particularly at low temperatures, which is undesirable.

The molecular weight for Pv is 300-1000 (20°C
) 3 to 10 cP in terms of 4% aqueous solution dust) is desirable.

If it is less than 300, water resistance and toughness are insufficient.

If it exceeds 1000, there is no particular problem in terms of characteristics, but
The viscosity of the aqueous solution and the viscosity of the emulsion after addition increase,
It becomes difficult to add, it becomes impossible to print, it becomes impossible to add to the desired PVIJ, or it becomes necessary to lower the solid content (evaporation residue or non-volatile content) in order to lower the viscosity. So, I don't like it very much.

As mentioned above, vinyl acetate copolymer emulsion is PV
Various properties can be improved by using A as a protective colloid or adding PVA, but there is a limit to the amount of PVA due to water resistance, etc., and if the Tg is less than 15°C, the blocking resistance cannot be improved. However, if the Tg exceeds +10°C, it becomes impossible to obtain sufficient anti-slip properties for practical use. An example of a vinyl acetate copolymer weight emulsion of PVA protective colloid that satisfies these conditions is Sumikaflex's 470 ('r
g = ooC, PVA = IO parts by weight), 471 (T
g=8℃, PVA=10fflffi part), 473 (
Tg=-3°c, PVA=10 parts by weight), ■Kuraray's EVA emulsion Panflex 0M-28 (T
g -5°c, PVA = 10 parts by weight), etc.

In addition, the copolymer emulsion of PVA protective colloid is
The purpose can be achieved even if PVA is used as the only protective colloid, or other protective colloids and surfactants are used in combination.

Although the initial objective can be achieved to some extent even when the vinyl acetate copolymer emulsion of PVA protective colloid alone has a Tg of 15°C to +10°C, some concerns remain regarding the bronking resistance. For this reason, if an emulsion with a high Tg is added, the blocking resistance will be improved, but the anti-slip property will be reduced and favorable results will not be obtained.
When a self-crosslinking emulsion is added at a temperature of preferably 5 to 20° C., the anti-blocking property is improved with very little deterioration in the anti-slip property.

This self-crosslinking emulsion has a Tg of O~3
If the emulsion has self-crosslinking properties at 0″C,
Although this objective is achieved, it is a prerequisite that the PVA protective colloid is miscible with the vinyl acetate copolymer emulsion, and for this purpose it is desirable to have vinyl acetate units in the resin component.

Furthermore, it is more preferable if PVA is used as a protective colloid. An example of an emulsion that satisfies this condition is Sumiriki 7 L/, 2.75
2 (Tg=15°C, PV/M: nonionic activator),
701 (Tg=15°C, PVA and nonionic activator and anionic activator), 703 (Tg=I5°C, PV
A and nonionic activators).

In addition, these self-crosslinking emulsions account for 5% of the total resin content.
If it exceeds 0% by weight, the anti-slip properties will be significantly reduced, which is not preferable.

Furthermore, in order to achieve the object of the present invention, the pH should be 7 or less, preferably 4 to 4, due to the problem of redissolving water-based ink.
6.5 is desirable, and in order to obtain excellent high-speed printing suitability for flexo printing etc., thixotropic property (ASTM-D-
2556, using a rotating BM type viscometer at a rotation speed of 6 r.
The value obtained by dividing the viscosity measured in pm by the viscosity measured at 6 Orpm (denoted as T, I value) is 1.2 to 3.0.
, preferably 1.5 to 2.5. T
If the T, I value exceeds 3.0, the viscosity decreases during high-speed printing, making it impossible to obtain a sufficient coating amount or making the coating amount uneven, which is undesirable. If it is less than 2, the coating agent cannot be transferred by the pump of the printing machine, which is undesirable.If the T and I values exceed 3.0, 1) by adding VA or a nonionic activator, etc. T and I values can be lowered. Also,
If the T value is less than 1.2, it is adjusted by adding a thixotropic emulsion, a thickener, etc.

In addition, the load collapse prevention coating agent of the present invention has a vinyl acetate copolymer emulsion of VΔ protective colloid with an rg of 50 to 100 parts (solid content ratio) at 15 to +10°C, and a Tg of 0. Self-crosslinking emul 2570 at ~30°C
~50 parts by weight (solid content ratio) as the main component (preferably, the total amount of the mixture including the additive PVA for adjustment is 70 parts by weight or more of the total solids), has a pH of 7 or less, and has thixotropic properties. is 1.2 to 3.0, the objective is achieved and other additives such as acrylic emulsion, ethylene-acrylic emulsion, styrene-acrylic emulsion, vinyl chloride emulsion, styrene emulsion, urethane emulsion , emulsions and latex such as SBR latex, CR latex, and NBR latex, or as necessary, thickeners, viscosity modifiers, water-soluble polymers, antifoaming agents, dispersants, wetting agents, plasticizers, and film forming aids. agent, solvent, preservative, anti-piping agent, pH adjuster,
Pigments, inorganic powders and particles such as silica, calcium carbonate, and clay; organic powders and particles such as styrene-acrylic resin, polyethylene resin, and methyl meccrylate; or vinylidene chloride-acrylonitrile hollow particles. Thermoplastic hollow particles such as styrene-acrylic hollow particles may be added as long as the properties are not affected.

An anti-slip container can be obtained by applying the anti-slip coating of the present invention to at least one of the outer surface of the top and outer surface of the bottom of a paper container such as a cardboard. It may be applied to the entire coated surface or partially to the coated surface.

Partially means coating only the center of the coated surface,
There are methods such as coating only on the periphery, coating in several stripes vertically, horizontally or diagonally, coating in a grid or halftone pattern, etc., but with a small amount of coating. Halftone dot printing with an area ratio of 20 to 50% at lO to 40 lines/inch is particularly preferred from the viewpoint of providing excellent anti-slip properties and excellent anti-blocking properties.

As for the amount of coating, it is necessary to find the optimum conditions, as too much will reduce blocking resistance, and too little will not provide sufficient anti-slip properties. The optimal conditions will vary depending on the case of single-sided coating, full-surface coating and partial coating, the coating change for partial coating, the shape and surface condition of the paper container, etc. -For boat fishing, the solid content is 1~
10 g/rrr, preferably 2 to 5 g/nr [Function] As explained above, the coating agent for preventing cargo collapse for paper containers according to the present invention has a
The protective colloid vinyl acetate copolymer emulsion has toughness, excellent anti-slip properties, and good anti-blocking properties.
It takes advantage of the excellent high-speed printing suitability and non-re-dissolving properties of water-based inks, and by incorporating a self-crosslinking emulsion with a Tg of 0 to 30°C, it has excellent blocking resistance without impairing other physical properties. This coating agent for paper containers and anti-slip cardboard has excellent high-speed printing suitability, anti-slip properties, anti-blocking properties, and anti-abrasion properties without re-dissolving water-based ink. The case can be provided at a low cost.

〔Example〕

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Example 1 Panflex 0M-28 [-PvA HojI manufactured by Kuraray
A colloidal EVA emulsion containing 10 parts of PVA (parts by weight based on the resin content, the same below), a Tg of 5°C, and 1100 parts by weight of a solid content of 55% (by weight, the same below). 15 parts of water was added to obtain the coating agent shown in Table 1. The viscosity listed in Table 1 is the viscosity measured at 20°C and 30 rpm using a BM type viscometer with rotor Nα2.
10 parts of a 30% aqueous solution of -205 (1 polyvinyl alcohol manufactured by Kuraray, saponification degree 88%, 4% aqueous solution viscosity 5 cP) and 15 parts water were added to obtain the coating agent shown in Table 1.

Example 3 To 90 parts of Panflex 0M-28, 1 part of Sumikaflex 701 (self-crosslinking EVA emulsion manufactured by Sumikagaku Kogyo ■, Tg 15°C, solid content 50%) was added.
0 parts and 10 parts of water were added to obtain the coating agent shown in Table 1.

Example 4 10 parts of Sumikaflex 701 and 12 parts of water were added to Panflex 0M-28 so ar+ to obtain the coating agent shown in Table 1.

Example 5 Sumikaflex 471 (P manufactured by Sumikagaku Kogyo I (1)
EVA emulsion of VA protective colloid, PVA is 1
Sumikaflex 752 (self-crosslinking EVA emuldigon manufactured by Sumikagaku Kogyo ■, Tg is 15°C, solid content is 50%) is added to 95 parts of Sumikaflex 752 (self-crosslinking type EVA emuldigon, Tg is 15°C, solid content is 50%). 5 parts and 10 parts of water were added to obtain the coating agent shown in Table 1.

Example 6 70 parts of Sumikaflex 473 (an EVA emulsion of PVA Ho 55 colloid manufactured by Sumikagaku Kogyo ■, containing 10 parts of PVA and 57% solid content at Tg of 13°C) was mixed with Sumikaflex 703 (Sumikaflex 703) Self-crosslinking EVA emulsion manufactured by Kagaku Kogyo W, Tg is 15°C, solid content is 5.
0%) and 0 parts of Suiko were added to obtain the coating agent shown in Table 1.

Example 7 50 parts of Sumikaflex 473, 30 parts of Sumikaflex 703, and 30% of Poval P VA-205
20 parts of the aqueous solution and 12 parts of water were added to obtain the coating agent shown in Table 1.

Example 8 80 parts of Panflex 0M-28 was mixed with Sumikaflex 850 (a self-crosslinking ethylene-vinyl acetate-vinyl chloride copolymer emulsion manufactured by Sumikagaku Kogyo G.Shu), and T.
30° C., solid content 50%) and 5 parts of water were added to obtain the coating agent shown in Table 1.

Comparative Example 1 50 parts of Acronal YJ-2741D (a styrene-acrylic co-lj emulsion manufactured by Mitsubishi Yuka Birdishe ■, T g - 30" C1 solid content 55%) was added YJ-2730D (Acrylic copolymer emulsion manufactured by Mitsubishi Yuka Pardish ■, T
50 parts of 1% solids) were added to obtain the coating agent shown in Table 1.

Comparative Example 2 Acronal YJ-2715D (styrene-acrylic copolymer emulsion manufactured by Mitsubishi Yuka Verdissier ■,
20 parts of AT-30A (colloidal silica manufactured by Asahi Denka Kogyo ■, solid content 30%) were added to 80 parts of Tg 12°C (solid content 48%), and the coating shown in Table 1 was applied. Comparative Example 3 Sumikaflex 401 (EvA emulsion product manufactured by Sumikagaku Kogyo ■, Tg: 8℃, 1! SJ type content: 55%)
) was added with an aqueous solution (solid content 7.5%, pH 8.5) of an ammonium salt of an alkali-soluble water-soluble mJIi methyl vinyl ether/maleic anhydride copolymer.
By adding 20 parts of this and 12 parts of water, the coating agent shown in Table 1 was obtained.

Comparative Example 4 Boncourt DV-767 (Dainippon Ink Chemical Industry 91)
A colloidal silica-acrylic resin composite particle emulsion manufactured by
10 parts of the aqueous solution of the same alkali-soluble resin used in Comparative Example 3 to obtain the coating agent shown in Table 1.

(Margin below) Table 1 The coating agents of Examples 1 to 8 and Comparative Examples 1 to 4 were applied to the entire surface of a corrugated board sheet (manufactured by Honshu Paper Corporation) whose surface was flexographically printed with blue water-based flexo ink, with a solid content of 4
g/+rr and dried at room temperature, and the evaluation results of the obtained slip-proof corrugated cardboard sheet and the corrugated cardboard sheet before coating are shown in Table 2.

The evaluation items, evaluation method, and judgment criteria in Table 2 are as follows.

A. Effect of preventing load collapse (slip resistance) Two test cardboards cured at 20°C x 65% RH for 24 hours had a coating surface of 10g/cj on the contact surface.
The angle at which the cardboard on top slides (sliding angle) when tilted was measured 50 times with a load of

In this test, the temperature is preferably 45 degrees or more for practical purposes, but 50 degrees or more is more preferable in consideration of variations in the coated product.

B. Abrasion Resistance In the above anti-slip property test, the average value of the 46th to 50th tests was calculated, and the value was subtracted from the above anti-slip property result.

In this test, it is desirable that the slip angle decreases by 2 degrees or less.

C0 Blocking Resistance The coated surfaces of the two test cardboards were placed together at 40°C.
× Applying a load of 320 g/cJ at 90% RH for 24 hours,
Observe the condition when removed. ◎ if there is almost no resistance when peeling off using this method, ○ if there is considerable resistance but no change in appearance, Δ if there is some damage to the surface ink layer, and Δ if the ink layer is severely destroyed. ,
A case where the aesthetic appearance has been impaired is marked as ×.

D. Place a drop of coating agent on the blue ink printed edge of a water-based ink redissolved cardboard sheet and spread it over the unprinted area with a glass rod. If the unprinted area is not colored at all, O1 will show some color. If it is marked, it is marked as △, and if it becomes clearly blue, it is marked as ×.

Table 2 Examples 2 to 8 all exhibited excellent properties in terms of anti-slip properties, abrasion resistance, blocking resistance, and water-based ink resolubility.

Although the blocking resistance of Example I was slightly poor, it was within a practical range, and the other properties were completely satisfactory.

Comparative Examples 1 and 2 had insufficient anti-slip properties and abrasion resistance, and had poor water-based ink re-dissolution properties.

Comparative Examples 3 and 4 had relatively good anti-slip properties, abrasion resistance, and anti-blocking properties, but had poor water-based ink redissolution properties.

Coating Test Using Evaluation Examples 4 and 5 and Comparative Examples 3 and 4, water-based/ink printing and application of the anti-slip coating agent were performed consecutively.

The first color unit of a three-color flexo printing machine printed blue water-based ink on the top surface of the box, and the second color unit applied a coating agent.

The coating Everturn was applied by applying a solid coat to the entire bottom surface of the cardboard case, and by applying halftone dots to both the top and bottom surfaces at 20 lines/inch with an area ratio of 40%, and the line speed was 100 m/min.

First, using Example 4, the printing press was adjusted so that the coating amount was 5 g/xd for solid coating and 2 g/nr for halftone dots, and Example 5 and Comparative Example 3 were also used. It was conducted under the same conditions. However, in Comparative Example 4, the liquid did not flow through the printing machine's circulation pump, so the viscosity was lowered to a flowable state and adjusted to obtain the maximum amount of coating, but the solid coating was 2.0 to 2. .5g/n, halftone dot 0.8-1.3
g10f was the limit.

Cut the cardboard from the top and bottom of the 5th and 300th sheets after printing started, and measure the anti-slip properties. At the same time, evaluate by observing the bleeding of water-based ink on the top of the box and the coloring of the coating agent. did.

The results are shown in Table 3.

Examples 4 and 5 have good anti-slip properties and ink re-dissolving properties, and are excellent in high-speed printing suitability.

Comparative Examples 3 and 4 have problems in both anti-slip properties and ink redissolution properties.

Table 3 [Effects of the Invention] As specifically shown in the Examples above, the coating agent for preventing cargo collapse for paper containers according to the present invention has better anti-slip properties, abrasion resistance, and anti-blocking properties than conventional coatings. It has excellent properties, and by coating it, it is possible to obtain high-quality anti-slip cardboard cases.

Furthermore, since it has excellent high-speed printing suitability and water-based ink resolubility, it can be coated simultaneously with water-based ink printing, resulting in extremely excellent workability.

Patent applicant: Cemedine Co., Ltd.

Claims (3)

[Claims] (1) Vinyl acetate copolymer emulsion of polyvinyl alcohol protective colloid with Tg of -5 to +10°C 50 to 1
The main component is a mixture of 0.00 parts by weight (solid content ratio) and 0 to 50 parts by weight of a self-crosslinking emulsion with a Tg of 0 to 30°C, a pH of 7 or less, and a thixotropic property of 1.2 to 3.0.
A coating agent for preventing load collapse for paper containers, which is characterized by: (2) A claim characterized in that the vinyl acetate copolymer emulsion is an ethylene-vinyl acetate copolymer emulsion containing 50% by weight or more of the total resin component of vinyl acetate units and ethylene units. (1) Coating agent for paper containers to prevent cargo from collapsing. (3) The coating agent for preventing cargo collapse for paper containers according to claim (1) or claim (2) is applied entirely or partially to at least one of the upper outer surface and the bottom outer surface of the container. Engineered slip-proof cardboard case.