JP7150577B2 - SOLVENT-BASED GRAVURE PRINTING INK COMPOSITION FOR CONTAINER AND CONTAINER - Google Patents

Description

The present invention relates to a solvent-based gravure printing ink composition for containers and containers. More specifically, the present invention contains a biomass component and has excellent physical properties such as heat resistance, abrasion resistance, stain resistance, alcohol abrasion resistance, water abrasion resistance, etc., and also has excellent printing density. It relates to a solvent-based gravure printing ink composition for containers and containers.

Conventionally, paper substrates such as cigarettes, paper cups, candy boxes and the like are printed by gravure using a solvent type gravure printing ink composition for paper. As such a solvent-type gravure printing ink composition for paper, Patent Document 1 discloses a solvent-type gravure printing ink composition for paper containing nitrocellulose and a polymerized rosin containing a biomass component.

JP 2016-50286 A

However, the ink composition described in Patent Document 1 has room for improvement in various physical properties such as heat resistance, abrasion resistance, and stain resistance. Moreover, when the overcoat is not applied, the resulting container has room for improvement in terms of alcohol resistance and water resistance to abrasion. In addition, when printing is performed on paper in the container laminate, the paper is uncoated paper, and there is room for improvement in the print density obtained.

The present invention has been made in view of such conventional problems, and contains a biomass component and has heat resistance, abrasion resistance, stain resistance, alcohol resistance, and water abrasion resistance. It is an object of the present invention to provide a solvent-type gravure printing ink composition for containers and a container, which are excellent in various physical properties such as a printing density.

As a result of intensive studies to solve the above problems, the present inventors have found that a solvent-type gravure printing ink composition for containers uses wax with a specific particle size, and more preferably silica with a specific particle size. The present inventors have found that the above problems can be solved by using a binder resin containing a vinyl chloride-vinyl acetate copolymer as the binder resin, and have completed the present invention. The present invention for solving the above problems mainly includes the following configurations.

(1) A container laminate having at least a protective layer or a thermoplastic synthetic film, paper, and a printing layer, which are laminated in order, a container solvent-based gravure printing ink composition for forming the printing layer is a substance, comprising a binder resin, a pigment, a wax, and an organic solvent that does not contain an aromatic solvent, the binder resin comprising a vinyl chloride-vinyl acetate copolymer, and a rosin or a rosin derivative; A solvent-type gravure printing ink composition for containers, wherein the wax has a particle size of 30 μm or less.

According to such a configuration, the solvent-type gravure printing ink composition for containers contains wax having a particle size of 30 μm or less. Moreover, the binder resin contains a vinyl chloride-vinyl acetate copolymer. As a result, the solvent-based gravure printing ink composition for containers contains a biomass component, and the obtained container has excellent physical properties such as heat resistance, abrasion resistance, and stain resistance.

(2) The solvent-based gravure printing ink composition for containers according to (1), which further contains silica particles and has a particle size of 3 μm or less.

According to such a configuration, the solvent-type gravure printing ink composition for containers is excellent in printing density when printed on paper or uncoated paper in the laminate for containers.

(3) The binder resin contains a vinyl chloride-vinyl acetate copolymer and rosin or a rosin derivative at a ratio of 80/20 to 60/40 (mass ratio), and the solvent-type gravure printing ink composition for containers. The solvent-based gravure printing ink composition for containers according to (1) or (2), wherein the biomass component in the solid content of is 10% by mass or more.

According to such a configuration, the solvent-type gravure printing ink composition for containers has the advantage that various physical properties are not deteriorated, the substantial amount of carbon dioxide emissions can be reduced, and an environment-friendly ink can be obtained.

(4) The solvent-based gravure printing ink composition for containers according to any one of (1) to (3), wherein the rosin or rosin derivative has an acid value of 100 or less.

According to such a configuration, the solvent-type gravure printing ink composition for containers is more excellent in stability.

(5) The wax includes a large particle size wax having a particle size of 8 to 25 μm and a small particle size wax having a particle size of 0.5 to 3 μm, and the large particle size wax is a solvent-type gravure printing ink composition for containers. 0.05 to 0.5% by mass in the solid content of the product, and the small particle size wax is contained in 0.3 to 3% by mass in the solid content of the solvent-type gravure printing ink composition for containers, ( The solvent-based gravure printing ink composition for containers according to any one of 1) to (4).

With such a configuration, the solvent-type gravure printing ink composition for containers can further improve the heat resistance, abrasion resistance, and stain resistance of the resulting container.

(6) The container laminate is a container laminate in which a protective layer, paper, and a printing layer are laminated in this order, or a thermoplastic synthetic film, paper, a thermoplastic synthetic film, and a printing layer. The solvent-based gravure printing ink composition for containers according to any one of (1) to (5), which is a laminate for containers laminated in order.

According to such a configuration, it is possible to print on paper or a thermoplastic synthetic film, and the container obtained by using it contains a biomass component and has heat resistance, abrasion resistance, stain resistance, printing density, etc. Various physical properties are excellent.

(7) A container printed with the solvent-based gravure printing ink composition for containers according to any one of (1) to (6).

With such a configuration, the container contains a biomass component and has excellent physical properties such as alkali resistance, heat resistance, abrasion resistance, and stain resistance.

According to the present invention, there are provided a solvent-type gravure printing ink composition for containers containing a biomass component and excellent in various physical properties such as alkali resistance, heat resistance, abrasion resistance, and stain resistance, and a container. can be done.

<Solvent gravure printing ink composition for containers>
A solvent-based gravure printing ink composition for containers according to one embodiment of the present invention (hereinafter also referred to as an ink composition) comprises a protective layer or a thermoplastic synthetic film, paper, a thermoplastic synthetic film, and a printing layer in this order. An ink composition for forming a printed layer in a laminated laminate. The ink composition contains a binder resin, pigment, wax, silica particles, and an organic solvent containing no aromatic solvent. The binder resin contains a vinyl chloride-vinyl acetate copolymer and rosin or a rosin derivative. The wax has a particle size of 30 μm or less. Each of these will be described below.

(binder resin)
The binder resin includes a vinyl chloride-vinyl acetate copolymer and rosin and its derivatives.

Vinyl chloride-vinyl acetate copolymer resin As the vinyl chloride-vinyl acetate copolymer resin, copolymers of vinyl chloride monomers and vinyl acetate monomers conventionally used in ink compositions can be used. Among them, the vinyl chloride-vinyl acetate copolymer resin is advantageous in improving the various performances related to the problems of the present embodiment in a well-balanced manner in the organic solvent system of the environmentally friendly ink. - Vinyl acetate copolymer resins are preferred. Vinyl chloride-vinyl acetate copolymer resins having such hydroxyl groups can be obtained, for example, by partially saponifying the acetate moiety. In the case of a vinyl chloride-vinyl acetate copolymer resin having a hydroxyl group obtained by saponifying a part of the acetate moiety, a structural unit based on the reaction site of vinyl chloride in the molecule (formula 1 below), vinyl acetate The physical properties and dissolution behavior of the resin are determined by the ratio of the structural unit (formula 2 below) based on the reaction site of vinyl acetate and the structural unit (formula 3 below) based on the saponification of the reaction site of vinyl acetate. That is, the structural units based on the reaction site of vinyl chloride impart toughness and hardness to the resin film, the structural units based on the reaction site of vinyl acetate provide adhesiveness and flexibility, Structural units based on chemical formulas impart good solubility to environmentally friendly inks in organic solvent systems.
Formula 1 —CH ₂ —CHCl—
Formula 2 —CH ₂ —CH(OCOCH ₃ )—
Formula 3 —CH ₂ —CH(OH)—(polymerized rosin)

The vinyl chloride-vinyl acetate copolymer resin of the present embodiment preferably has a number average molecular weight of 10,000 or more, more preferably 15,000 or more. Also, the number average molecular weight of the vinyl chloride-vinyl acetate copolymer resin is preferably 35,000 or less, more preferably 30,000 or less. When the number average molecular weight of the vinyl chloride-vinyl acetate copolymer resin is within the above range, the ink composition has various physical properties such as heat resistance, abrasion resistance, stain resistance, alcohol resistance, and resistance to organic solvents. can provide good solubility and optimum ink viscosity.

The content of the vinyl chloride-vinyl acetate copolymer resin is not particularly limited. For example, the content of the vinyl chloride-vinyl acetate copolymer resin is preferably 5% by mass or more, more preferably 8% by mass or more, based on the solid content of the ink composition. Also, the content of the vinyl chloride-vinyl acetate copolymer resin is preferably 20% by mass or less, more preferably 17% by mass or less, based on the solid content of the ink composition. When the content of the vinyl chloride-vinyl acetate copolymer resin is within the above range, the ink composition has various physical properties such as heat resistance, rub resistance, stain resistance, and alcohol rub resistance, and has an optimum ink viscosity. has the advantage of being able to provide

- Rosin or rosin derivative Rosin or a rosin derivative is blended to improve the abrasion resistance of the resulting container.

The rosin or rosin derivative is not particularly limited. Rosins are, for example, polymerized rosins obtained by polymerizing natural rosins such as gum rosin, tall oil rosin and wood rosin in the presence of a non-halogen catalyst. More specifically, rosin and its derivatives are treated in the presence of non-halogen catalysts such as mineral acids such as sulfuric acid, organic acids such as formic acid, and sulfonic acid catalysts such as paratoluenesulfonic acid and methylsulfonic acid. It can be obtained by polymerizing natural rosin in an organic solvent such as toluene or xylene, and then removing the catalyst, solvent and, in some cases, unreacted rosin by means of distillation or the like.

A polymerization method is not particularly limited. For example, the polymerization method may be a method using a polymer catalyst having an acidic functional group such as a sulfonic acid group. The non-halogen catalyst used is preferably a sulfonic acid catalyst, more preferably paratoluenesulfonic acid or methylsulfonic acid.

The rosin of the present embodiment may be various derivatives instead of the above rosin. To give an example, the rosin derivative may be various modified products of polymerized rosins, such as stabilized polymerized rosins obtained by disproportionating or hydrogenating polymerized rosins, and unsaturated carboxylic acids in polymerized rosins. Unsaturated acid-modified polymerized rosins obtained by adding acids may also be used. These derivatives can be obtained by various known methods. Examples of unsaturated carboxylic acids include maleic acid, maleic anhydride, fumaric acid, itaconic acid, crotonic acid, cinnamic acid, acrylic acid and methacrylic acid. About 1 to 30 parts by mass of the unsaturated carboxylic acid can be used with respect to 100 parts by mass of the starting rosins. The resulting polymerized rosin has two or more carboxyl groups in its molecule.

The number average molecular weight of the rosin or rosin derivative of the present embodiment is preferably 500 or more, more preferably 800 or more. Also, the number average molecular weight of the rosin or rosin derivative is preferably 7,000 or less, more preferably 5,000 or less. When the number average molecular weight of the rosin or rosin derivative is within the above range, the ink composition has various physical properties such as good solubility in organic solvents and heat resistance, rub resistance, stain resistance, and alcohol rub resistance. There is an advantage that it is possible to achieve both

The acid value of the rosin or rosin derivative is preferably 200 or less, more preferably 100 or less. When the acid value is within the above range, the stability of the ink composition is improved.

The content of rosin or rosin derivative is not particularly limited. For example, the content of rosin or rosin derivative is preferably 13% by mass or more, more preferably 15% by mass or more, based on the solid content of the ink composition. The content of rosin or rosin derivative is preferably 30% by mass or less, more preferably 25% by mass or less, based on the solid content of the ink composition. When the content of the rosin or rosin derivative is within the above range, the ink composition contains 10% by mass or more of the biomass component and is advantageous in terms of resolubility.

The binder resin of the present embodiment preferably contains a vinyl chloride-vinyl acetate copolymer and rosin or a rosin derivative in a ratio of 80/20 to 60/40 (mass ratio). By containing the vinyl chloride-vinyl acetate copolymer and the rosin or rosin derivative in such a ratio, the ink composition does not deteriorate in various physical properties, can substantially reduce carbon dioxide emissions, and is an environmentally friendly ink. has the advantage of obtaining

The binder resin of the present embodiment contains the vinyl chloride-vinyl acetate copolymer and the rosin or rosin derivative in the above ratio, so that the content of the biomass component is 10% by mass in the solid content of the ink composition. It can be more. The content of the biomass component is preferably 10% by mass or more, more preferably 11% by mass or more. It is preferable to adjust the content and ratio of the rosin and its derivative so as to achieve such a biomass component content.

In addition to the vinyl chloride-vinyl acetate copolymer, rosin or rosin derivative, the binder resin may include, for example, nitrocellulose resin, acrylic resin, urethane resin, and the like.

The content of the binder resin during printing is not particularly limited. For example, the content of the binder resin in the ink composition is preferably 5% by mass or more, more preferably 8% by mass or more. Also, the content of the binder resin is preferably 20% by mass or less, more preferably 17% by mass or less, in the ink composition. When the content of the binder resin is within the above range, the resulting ink composition exhibits good physical properties of the coating film in the printed matter and has an appropriate viscosity range.

(pigment)
Pigments are exemplified by various inorganic pigments, organic pigments, etc. that can be generally used in ink compositions. Examples of inorganic pigments include titanium oxide, red iron oxide, antimony red, cadmium red, cadmium yellow, cobalt blue, Prussian blue, ultramarine blue, carbon black, and graphite. Examples of organic pigments include soluble azo pigments, insoluble azo pigments, azo lake pigments, condensed azo pigments, copper phthalocyanine pigments, and condensed polycyclic pigments.

The content of the pigment during printing is not particularly limited. For example, the organic pigment is preferably 5% by mass or more, more preferably 7% by mass or more, in the ink composition. Moreover, the organic pigment is preferably 13% by mass or less in the ink composition. The content of the inorganic pigment in the ink composition is preferably 5% by mass or more, more preferably 7% by mass or more. Moreover, the inorganic pigment is preferably 35% by mass or less in the ink composition. In addition, since the coloring power differs depending on the pigment, when a pigment with high coloring power such as carbon black is used, the content may be in the range of 5 to 13% by mass. The content may be in the range of 15 to 35% by weight when a pigment having a low tinting strength is used, as in the case of the present invention. If the content of the pigment in the ink composition is less than the above range, the resulting printed matter tends to have a low optical density. On the other hand, when the content of the pigment in the ink composition is more than the above range, the viscosity of the ink composition becomes high regardless of the pigment, and the printed matter tends to be easily stained. Also, if necessary, a dye may be used together with the pigment.

(wax)
Wax is added to improve the heat resistance, abrasion resistance and stain resistance of the resulting container.

Wax is not particularly limited. Exemplary waxes include polyethylene wax, polyethylene terephthalate (PTFE) wax, polycarbonate wax, melamine wax, and the like.

The particle size of the wax may be 30 μm or less, and more preferably 20 μm or less. Moreover, the lower limit of the particle size of the wax is not particularly limited. When the particle size of the wax is within the above range, the obtained container has excellent heat resistance, abrasion resistance and stain resistance.

The wax content is not particularly limited. For example, the wax content is preferably 0.5% by mass or more, more preferably 1% by mass or more, based on the solid content of the ink composition. The wax content is preferably 10% by mass or less, more preferably 7% by mass or less, based on the solid content of the ink composition. When the content of the wax is within the above range, the obtained container has excellent heat resistance, abrasion resistance and stain resistance.

It is more preferable that the wax of this embodiment contains a large particle size wax having a particle size of 8 to 25 μm and a small particle size wax having a particle size of 0.5 to 3 μm.

The particle size of the large particle size wax is preferably 8 μm or more, more preferably 10 μm or more. Moreover, the particle size of the large particle size wax is preferably 25 μm or less. When the particle size of the large particle size wax is within the above range, the obtained container has excellent abrasion resistance and stain resistance.

The content of the large particle size wax is not particularly limited. For example, the content of the large particle size wax is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, based on the solid content of the ink composition. Also, the content of the large particle size wax is preferably 0.5% by mass or less in the solid content of the ink composition. When the content of the large particle size wax is within the above range, the obtained container has excellent heat resistance.

The particle size of the small particle size wax is preferably 0.5 μm or more. Further, it is more preferable that the particle size of the small particle size wax is 3 μm or less. When the particle size of the small-particle-size wax is within the above range, the obtained container has excellent abrasion resistance and stain resistance.

The content of the small particle size wax is not particularly limited. For example, the content of the small particle size wax is preferably 0.3% by mass or more, more preferably 0.5% by mass or more, based on the solid content of the ink composition. Also, the content of the small particle size wax is preferably 3% by mass or less, more preferably 2% by mass or less, based on the solid content of the ink composition. When the content of the small particle size wax is within the above range, the obtained container has excellent abrasion resistance and stain resistance.

The method of mixing the large particle size wax and the small particle size wax is not particularly limited.

(silica particles)
The particle size of the silica particles is preferably 3 μm or less, more preferably 1 μm or less. If the average particle size exceeds 3 μm, the alcohol rubbing resistance tends to decrease when the resulting ink composition is used. In addition, the lower limit of the average particle size of the silica particles is not particularly limited.

The content of the silica particles is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, in the ink composition from the viewpoint that the resulting ink composition has excellent printability. In addition, the content of silica particles is preferably 2.0% by mass or less, more preferably 1.0% by mass or less. When the content of the silica particles is within the above range, the resulting ink composition is excellent in printability and the alcohol rubbing resistance of the resulting container.

(Organic solvent containing no aromatic solvent)
The organic solvent used in this embodiment does not contain an aromatic solvent. The organic solvent is blended to dissolve the pigment and binder resin. The organic solvent is not particularly limited. Examples of organic solvents include ketone organic solvents (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), ester organic solvents (methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, isobutyl acetate, etc.), Non-aromatic organic solvents such as alcoholic organic solvents (methanol, ethanol, n-propanol, isopropanol, butanol, etc.). By using these non-aromatic organic solvents, the ink composition is advantageous from an environmental point of view.

As for the organic solvent, in consideration of environmental issues and printability and drying properties of the ink, a mixed organic solvent of an ester organic solvent and an alcohol organic solvent is used. It is preferably used in the range of 40/60 to 95/5.

The content of the organic solvent is preferably 15.0% by mass or more in the ink composition from the viewpoint of excellent printability of the resulting ink composition. Moreover, the content of the organic solvent is preferably 90% by mass or less in the ink composition. When the content of the organic solvent is within the above range, the ink composition has excellent printability and can easily obtain sufficient color development.

(Optional component)
Various additives such as a plasticizer, a tackifier, a cross-linking agent, a lubricant, an anti-blocking agent, an antistatic agent, and a surfactant may be blended in the ink composition of the present embodiment.

A plasticizer is preferably blended in order to reduce residual solvent in the ink composition. The plasticizer is not particularly limited. By way of example, plasticizers are dioctyl sebacate, epoxidized soybean oil, fatty acid triglycerides, ethyltoluenesulfonic acid amide, acetyl tributyl citrate, stearic acid 2-ethylhexyl ester, palmitic acid 2-ethylhexyl ester, and the like.

When a plasticizer is included, the content of the plasticizer is not particularly limited. For example, the content of the plasticizer in the ink composition is preferably 0.1% by mass or more, more preferably 0.5% by mass or more. Also, the content of the plasticizer is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, in the ink composition. When the content of the plasticizer is within the above range, the residual solvent in the resulting ink composition is likely to be reduced.

The method for producing the ink composition of this embodiment is not particularly limited. To give an example, the ink composition is produced by stirring and mixing binder resin, pigment, wax, silica particles, organic solvent and various optional components, and then producing a masterbatch using various dispersing/kneading devices. It can be manufactured by adding and adjusting the remaining ingredients. In addition, when the viscosity of the ink composition is low, there is a possibility that the dispersion stability of the pigment and the like is lowered. On the other hand, when the viscosity is high, the ink composition requires a large amount of dilution in order to obtain a viscosity suitable for printing, which may make it difficult to handle printing plates using shallow plates. Therefore, the viscosity of the ink composition is preferably adjusted within the range of 3 to 20 mPa·s.

The ink composition has an appropriate number of seconds depending on the printing conditions at the ambient temperature during printing. It is preferably diluted with an organic solvent, if necessary, to the desired degree. Alternatively, the ink composition may be prepared by mixing materials without going through a masterbatch or the like, instead of using the above manufacturing method.

As described above, according to the present embodiment, it is possible to obtain an ink composition containing a biomass component and having various physical properties such as alkali resistance, heat resistance, abrasion resistance, and stain resistance, and excellent printing density.

<Print method>
A printing method according to one embodiment of the present invention is a method of printing the ink composition described above on a printing substrate by a gravure printing method using a gravure plate. That is, a general gravure printing method can be adopted for the ink composition. The conditions of the gravure printing method are the same as those of conventionally known methods and conditions. Uncoated paper, coated paper, and laminated paper are used as printing substrates.

The printing plate to be used may be a conventional plate cylinder (an intaglio plate made by a normal gravure plate making method, and the plate making method can be exemplified by engraving gravure, etc.), which forms cells shallower than the conventional plate cylinder ( shallow version) may be used. In the printing method of the invention of the present embodiment, the laminate can be obtained by printing the ink composition at the time of printing using the conventional printing plate or the shallow printing plate. can.

<Laminate>
The container laminate of one embodiment of the present invention is a container laminate in which a protective layer, paper, and a printing layer are laminated in order, or a thermoplastic synthetic film, paper, a thermoplastic synthetic film, It is a lamination for a container in which a printed layer is laminated in order. The ink composition is used to form a printed layer in such a laminated body for containers.

First, a laminate for a container in which a protective layer, paper, and a printing layer are laminated in order will be described. For the protective layer, wax or the like conventionally used for container laminates can be used. The paper is not particularly limited as long as it is paper that has been conventionally used for laminates for containers. The paper may be appropriately selected according to the application. For example, when the laminate is used as a beverage container, uncoated or coated paper having a basis weight of 50 to 500 g/m ² is used in terms of workability and shape retention. paperboard or the like.

Next, a laminate for a container in which a thermoplastic synthetic film, paper, a thermoplastic synthetic film, and a printed layer are laminated in this order will be described. The thermoplastic synthetic film that constitutes the laminate is not particularly limited. For example, thermoplastic synthetic films include polyolefins such as polypropylene and polyethylene; polyesters such as polyethylene terephthalate and polyethylene naphthalate; polyamides such as nylon 6 and nylon 66; polyvinyl chlorides such as hard vinyl chloride and soft vinyl chloride; Polystyrene and the like. In addition, the thermoplastic synthetic film is blended with various additives such as various rubbers, tackifying resins, softeners, coloring pigments, antioxidants, antistatic agents, slip agents, weather stabilizers, etc., as necessary. good too. Such thermoplastic synthetic films are placed on both sides of the paper. A method for laminating these is not particularly limited, and a conventionally well-known lamination method can be adopted. The paper is not particularly limited as long as it is conventionally used for laminated paper.

The container laminate is a paper or thermoplastic synthetic film further provided with a printed layer. The printed layer is a layer to which the ink composition is applied. The method for printing the ink composition is as described above.

The container laminate of the present embodiment may further include an overcoat layer that covers the printed layer.

The container laminate is appropriately molded and processed into a container. The container is suitably used as a beverage container such as a cup or a cup.

As described above, according to the present embodiment, it is possible to obtain a container containing a biomass component and having various physical properties such as heat resistance, abrasion resistance, and stain resistance, and excellent print density.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is by no means limited to these examples. Unless otherwise specified, "%" means "% by mass" and "parts" means "parts by mass".

The raw materials and preparation methods used are shown below.
<Pigment>
PY14
PR48
<Vinyl chloride vinyl acetate copolymer>
Solbin A (manufactured by Nissin Chemical Industry Co., Ltd.)
Solbin TA5R (manufactured by Nissin Chemical Industry Co., Ltd.)
<Rosin and its derivatives>
Maleic acid-modified rosin ester (acid value 39 mgKOH/g or less, manufactured by Arakawa Chemical Industries, Ltd.)
Maleic acid-modified rosin ester (acid value 100 mgKOH/g, manufactured by Arakawa Chemical Industries, Ltd.)
Maleic acid-modified rosin ester (acid value 170 mgKOH/g, manufactured by Harima Kasei Co., Ltd.)
<Wax>
Over 30 μm average particle size (manufactured by Polycon Co., Ltd.)
Average particle size 15 μm (manufactured by Polycon Co., Ltd.)
Average particle size 10 μm (manufactured by Nippon Shellac Industry Co., Ltd.)
Average particle size 8 μm (manufactured by Sasol)
Average particle size 1 to 2 μm (manufactured by Gifu Shellac Manufacturing Co., Ltd.)
Average particle size 2 μm (manufactured by Nippon Shokubai Co., Ltd.)
<Silica particles>
Average particle size: 0.016 μm (manufactured by Nippon Aerosil Co., Ltd.)
Average particle size: 0.028 μm (manufactured by Nippon Aerosil Co., Ltd.)
Average particle size: 0.115 μm (manufactured by Nippon Aerosil Co., Ltd.)
Average particle size: 2.7 μm (manufactured by Fuji Silysia Chemical Co., Ltd.)
Average particle size: 3.9 µm (manufactured by Fuji Silysia Chemical Co., Ltd.)

<Examples 1 to 21, Comparative Examples 1 to 4>
(Preparation of solvent-based gravure printing ink composition for containers)
Each material was kneaded with a paint conditioner according to the mass ratio (% by mass) shown in Table 1 below to prepare an ink composition. The obtained ink composition was evaluated for stability over time. Also, the resulting ink composition was subjected to gravure printing under the following conditions to obtain a laminate. Adhesion, rub resistance, water rub resistance, alcohol rub resistance, stain resistance, heat resistance, and print density were evaluated for the resulting laminate according to the following evaluation methods. Table 1 shows the results.

<Stability over time>
For the ink compositions of Examples 1 to 21 and Comparative Examples 1 to 4, the change in viscosity value before and after aging at 40 ° C. for 7 days (ink viscosity measurement data at 30 rpm with a Brookfield viscometer) indicates the viscosity stability over time. Evaluation was performed and evaluated according to the following evaluation criteria.
(Evaluation criteria)
A: The viscosity ratio after aging/before aging was less than 1.5.
B: The viscosity ratio after aging/before aging was 1.5 or more and less than 3.0.
C: The viscosity ratio after aging/before aging was 3.0 or more.

(Gravure printing conditions)
Structure of Laminate As a base material for printing, polylaminated paper obtained by laminating a paper layer surface with a polyethylene layer, and uncoated paper, which is not laminated with a resin layer on the paper layer surface and is not coated with a resin, were used. A printing layer was formed on the printing substrate under the following conditions.

(Conditions for forming printed layer)
100 parts by mass of each of the ink compositions of Examples 1 to 21 and Comparative Examples 1 to 4 was further diluted with a mixed solvent according to the formulation shown in Table 1, and the viscosity was adjusted to 15 using Zahn Cup No. 3 manufactured by Rigo Co., Ltd. adjusted to seconds. Each ink composition is printed on polylaminated paper and uncoated paper using a gravure printing machine under the following conditions and dried, and then a laminated white ink composition for flexible packaging is printed and dried under the following conditions to obtain printed matter. After obtaining, a print evaluation was performed. A specific evaluation method is shown below.
(Printing method/Printing conditions)
Coating machine: Gravure printing machine Coating speed: 150 m/min Printing plate: Printing plate: Direct 175-line solid plate Drying temperature: 55°C

<Adhesion>
Adhesiveness was evaluated from the ratio of the area where the ink film was peeled off from the adherend when a cellophane tape was attached to the printed surface of each printed matter immediately after printing and peeled off.
(Evaluation criteria)
A: It was not peeled off at all.
B: A part was peeled off.
C: All peeled off.

<Abrasion resistance>
Each printed matter obtained was evaluated using a Gakushin type fastness to rubbing tester.
Evaluation conditions: 500 g × 50 times, this paper: fine paper (evaluation criteria)
A: The printed surface could not be removed even after rubbing 50 times or more.
B: The printed surface was removed by rubbing 10 to 49 times.
C: The printed surface was removed by rubbing 1 to 9 times.

<Stain resistance>
Each printed matter obtained was evaluated using a Gakushin type fastness to rubbing tester.
Evaluation conditions: 500 g × 50 times, this paper: fine paper (evaluation criteria)
A: The paper was not stained even after rubbing 50 times or more.
B: Ink adhered to the paper after rubbing 10 to 49 times.
C: Ink adhered to the paper after rubbing 1 to 9 times.

<Water and abrasion resistance>
Each printed matter obtained was evaluated using a Gakushin type fastness to rubbing tester.
Evaluation conditions: 200 g × 5 times, this paper: 5 drops of water dropped on kanakin cloth (evaluation criteria)
A: The printed surface could not be removed.
B: Part of the printed surface was removed.
C: The entire printed surface was removed.

<Alcohol resistance to abrasion>
Each printed matter obtained was evaluated using a Gakushin type fastness to rubbing tester.
Evaluation conditions: 200 g × 5 times, this paper: 5 drops of a mixture of ethanol / water = 8/2 dropped on Kanakin cloth (evaluation criteria)
A: The printed surface could not be removed.
B: Part of the printed surface was removed.
C: The entire printed surface was removed.

<Heat resistance>
Using a heat seal tester equipped with a hot plate having a thermal gradient of 100° C., the printed surface of each printed matter was pressed against the aluminum foil at a pressure of 2.0 kg/cm ² for 1 second.
(Evaluation criteria)
A: The coating film on the printed surface was not removed.
B: Part of the coating film on the printed surface was removed.
C: All of the coating film on the printed surface was removed.

<Print Density>
The printing density of the resulting prints was evaluated in comparison with products on the market.
(Evaluation criteria)
A: The printing density was higher than that of products on the market.
B: The printing density was equivalent to that of the market product.
C: Concentration was lower than the marketed product.

As shown in Table 1, the ink compositions and printed matter of Examples 1 to 21 had excellent adhesion, rub resistance, water rub resistance, alcohol rub resistance, stain resistance, heat resistance, and print density. was also good. On the other hand, the ink composition and the printed matter of Comparative Example 1, in which the average particle diameter of the wax used was too large, were not excellent in stain resistance. The ink composition and the printed material of Comparative Example 2, in which the average particle size of the silica particles used was too large, were not excellent in rub resistance and alcohol rub resistance, and the print density was low. The ink composition and printed matter of Comparative Example 3, which did not use wax, were inferior in rub resistance, water rub resistance, alcohol rub resistance, stain resistance and heat resistance. The ink composition and printed material of Comparative Example 4, which did not use silica particles, had low print density.

Claims (6)

A container laminate having at least a protective layer or a thermoplastic synthetic film, paper, and a printing layer and laminated in order,
A solvent-type gravure printing ink composition for containers for forming the printing layer,
including a binder resin, a pigment, a wax, and an organic solvent that does not contain an aromatic solvent;
The binder resin contains a vinyl chloride vinyl acetate copolymer and rosin or a rosin derivative,
The wax has a particle size of 30 μm or less ,
Furthermore, a solvent-type gravure printing ink composition for containers, which contains silica particles, and the particle size of the silica is 3 μm or less . The binder resin contains a vinyl chloride-vinyl acetate copolymer and rosin or a rosin derivative in a ratio of 80/20 to 60/40 (mass ratio),
The solvent-type gravure printing ink composition for containers according to claim 1 , wherein the biomass component in the solid content of said solvent-type gravure printing ink composition for containers is 10% by mass or more. 3. The solvent-based gravure printing ink composition for containers according to claim 1 , wherein said rosin or rosin derivative has an acid value of 100 or less. The wax includes a large particle size wax with a particle size of 8 to 25 μm and a small particle size wax with a particle size of 0.5 to 3 μm,
The large particle size wax is contained in the solid content of the solvent type gravure printing ink composition for containers in an amount of 0.05 to 0.5% by mass, and the small particle size wax is contained in the solvent type gravure printing ink composition for containers. The solvent-based gravure printing ink composition for containers according to any one of claims 1 to 3 , which is contained in a solid content of 0.3 to 3% by mass. The container laminate is a container laminate in which a protective layer, paper, and a printing layer are laminated in order, or a thermoplastic synthetic film, paper, a thermoplastic synthetic film, and a printing layer are laminated in order. The solvent-based gravure printing ink composition for containers according to any one of claims 1 to 4 , which is a laminated body for containers. A container printed with the solvent-based gravure printing ink composition for containers according to any one of claims 1 to 5 .