JP2023086166A - Ink composition and sheet body - Google Patents

Abstract

To provide an ink composition which is provided in a base material sheet, and thereby facilitates manufacture of a sheet body that has good blocking resistance and suppresses curling.SOLUTION: An ink composition contains a binder resin, at least one inorganic particle of a phosphate glass particle containing a silver oxide and a zirconium phosphate particle supporting a silver ion, and a lubricant, wherein the binder resin contains a combination of an acrylic resin and a vinyl chloride-vinyl acetate-based copolymer resin; an average particle diameter of the inorganic particle is 0.1-20 μm; a content of the inorganic particle is 1-15 mass% based on the mass of the solid content of the ink composition, and the lubricant contains at least one selected from the group consisting of a polyolefin wax and a fatty acid amide.SELECTED DRAWING: None

Description

The present invention relates to an ink composition and a sheet body.

BACKGROUND ART Inks are widely used in various industrial fields for printing on substrates, imparting information, decorating, surface protection, and the like. For example, as a substrate on which ink is applied, such as a packaging material, a film-like or sheet-like substrate (base sheet) such as paper or a plastic film is often used.

In the case of industrially mass-producing a sheet body having an ink layer provided by coating or printing ink on a base sheet, a plurality of the sheet bodies are often stacked and left in that state for a while. There are many. As a result, a phenomenon (blocking) may occur in which the ink layers in the sheet body or the ink layer and the surface of the base sheet adhere to each other and cannot be easily peeled off. In this way, the ink provided on the base sheet is required to have a performance (blocking resistance) that does not adhere to each other or does not easily adhere to each other when the ink layers or the surface of the ink layer and the base sheet are in close contact. .

As one means for improving the anti-blocking property of ink, it has been practiced to incorporate silica into the ink. For example, Patent Document 1 discloses a laminating gravure ink for forming a printed layer of a given laminate, which contains an organic pigment, a given binder resin, an organic solvent, and a given amount of silica particles and fatty acid amide. What does is disclosed.

JP 2018-135411 A

The present inventors applied or printed an ink composition on a substrate sheet to produce a sheet provided with a dry coating layer (ink layer) of the ink composition, and found that the blocking resistance of the sheet was improved. In order to improve it, an investigation was conducted using an ink composition containing silica. As a result, when the ink composition contains silica in order to improve blocking resistance, the type of binder resin contained in the ink composition and the type of substrate sheet on which the ink composition is applied are also affected. However, it has been found that the edge of the base sheet provided with the ink layer may warp (hereinafter sometimes referred to as "curling").

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an ink composition which, when applied to a substrate sheet, facilitates the production of a sheet having good blocking resistance and suppressed curling.

The present invention provides an ink composition comprising a binder resin; inorganic particles of at least one of phosphate glass particles containing silver oxide and zirconium phosphate particles supporting silver ions; and a lubricant. The binder resin includes a combination of an acrylic resin and a vinyl chloride-vinyl acetate copolymer resin, the average particle size of the inorganic particles is 0.1 to 20 μm, and the content of the inorganic particles is The lubricant is 1 to 15% by mass based on the mass of the solid content of the ink composition, and the lubricant comprises at least one selected from the group consisting of polyolefin waxes and fatty acid amides.

According to the present invention, it is possible to provide an ink composition which, when applied to a substrate sheet, facilitates the production of a sheet having good anti-blocking properties and suppressed curling.

Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments.

As described above, the present inventors used silica to improve the anti-blocking property of the sheet body when manufacturing the sheet body provided with the dry film layer by coating or printing the ink composition on the base sheet. was investigated using an ink composition containing As a result, the anti-blocking property of the sheet body was good due to the addition of silica. In comparison, it was found that the sheet body tends to curl.

When the sheet body is curled, it not only impairs its appearance, but may also cause poor product performance and workability depending on the use of the sheet body. The phenomenon of curling is caused by the absorption of ink into the base sheet (e.g. paper), the difference in properties (e.g. expansion coefficient) between the base sheet (e.g. plastic film) and the ink layer, and the effects of residual volatile components. The cause is thought to be shrinkage of the layer, environmental changes such as temperature and humidity, and the like. However, it is considered that these causes may change depending on the type of product, the production situation, etc., and curling may occur due to multiple causes. Further, the phenomenon of curling is considered to occur more easily as the thickness of the base sheet is thinner, and thinning of products typified by electrical and electronic parts is also required for products in various fields. From the above, it is considered that an ink composition capable of not only improving blocking resistance but also suppressing curling is industrially useful.

Therefore, the present inventors have made intensive studies using various inorganic particles instead of silica for the purpose of providing an ink composition that facilitates the production of a sheet body with good blocking resistance and suppressed curling. piled up. As a result, the present inventors found that both blocking resistance and curl suppression can be achieved by including a specific amount of specific inorganic particles together with a specific binder resin and a lubricant in the ink composition, leading to the present invention. rice field.

That is, the ink composition of one embodiment of the present invention comprises a binder resin, and inorganic particles of at least one of phosphate glass particles containing silver oxide and zirconium phosphate particles carrying silver ions. , and a lubricant. The binder resin includes a combination of acrylic resin and vinyl chloride-vinyl acetate copolymer resin. The average particle size of the inorganic particles is 0.1 to 20 μm, and the content of the inorganic particles is 1 to 15% by mass based on the mass of the solid content of the ink composition. The lubricant contains at least one selected from the group consisting of polyolefin waxes and fatty acid amides. In this specification, the phosphate glass particles containing silver oxide and the zirconium phosphate particles carrying silver ions may be collectively referred to simply as "inorganic particles".

By applying the ink composition to a substrate sheet described below by a technique such as coating or printing, a sheet body (coated or printed matter) in which a dry film layer of the ink composition is provided on the substrate sheet can be obtained. . The ink composition contains a combination of an acrylic resin and a vinyl chloride-vinyl acetate copolymer resin as a binder resin, and polyolefin wax and/or fatty acid amide as a lubricant. In addition, the ink composition contains inorganic particles having an average particle size of 0.1 to 20 μm of at least one of phosphate glass particles containing silver oxide and zirconium phosphate particles supporting silver ions. It contains 1 to 15% by mass in the solid content of the product. Therefore, it is possible to obtain a sheet body having good blocking resistance and suppressed curling. From the viewpoint of easily exhibiting this effect, a preferable configuration of the ink composition and the like will be described below.

The ink composition comprises at least one inorganic particle selected from phosphate glass particles containing silver oxide and zirconium phosphate particles supporting silver ions, and has an average particle size of 0.1 to 20 μm. Contains inorganic particles. The ink composition containing the specific inorganic particles facilitates the production of a sheet body having good blocking resistance and suppressed curling, and in addition, it is possible to form a dry film layer capable of exhibiting antibacterial properties. I can expect it. The zirconium phosphate particles carrying silver ions are particles in which hexagonal zirconium phosphate, which is an inorganic ion exchanger, carries silver ions by ion exchange. In this specification, "silver ion-supported zirconium phosphate particles" may be referred to as "silver ion-supported zirconium phosphate particles". Further, in this specification, "phosphate glass particles containing silver oxide" may be referred to as "phosphate glass particles containing silver oxide" or simply "phosphate glass particles".

Each average particle size of the silver oxide-containing phosphate glass particles and the silver ion-supporting zirconium phosphate particles is 0.1 to 20 μm. From the viewpoint of ease of mixing and dispersing into the ink composition and ease of handling, the average particle size is preferably 0.1 μm or more, more preferably 0.2 μm or more, and more preferably 0.3 μm or more. is more preferable. On the other hand, from the viewpoint of more easily suppressing curling and the viewpoint of improving the abrasion resistance of the dry film layer, the average particle size is preferably 15 μm or less, more preferably 8 μm or less, and 5 μm or less. It is more preferable that the thickness is 2 μm or less. In the present specification, the average particle size means the particle size (median size; _D50 ) at which cumulative 50% of the volume-based particle size distribution is measured by a laser diffraction/scattering method.

The ink composition more preferably contains at least the phosphate glass particles (silver oxide-containing phosphate glass particles) as the inorganic particles. The shape of the silver oxide-containing phosphate glass particles may be spherical, polyhedral, etc. Polyhedrons (eg, 6-20-hedrons) composed of a plurality of angles and faces are preferred.

When the shape of the silver oxide-containing phosphate glass particles is polyhedral, it becomes easier to mix and disperse the silver oxide-containing phosphate glass particles in the ink composition. Further, when the shape of the silver oxide-containing phosphate glass particles is polyhedral, the silver oxide-containing phosphate glass particles are easily dispersed uniformly in the binder resin in the dry film layer (ink layer) of the ink composition. . Furthermore, when the shape of the silver oxide-containing phosphate glass particles is polyhedral, silver oxide-containing phosphate glass particles are difficult to reaggregate during the production of the silver oxide-containing phosphate glass particles or when used as a component of an ink composition. It becomes easier to control the average particle size of the contained phosphate glass particles.

The silver oxide-containing phosphate glass particles contain silver oxide (Ag ₂ O) as a constituent. In the ink composition and/or its dry film layer, the silver oxide-containing phosphate glass particles can dissolve the glass component and elute Ag ions. Due to the presence of Ag ions, it is also possible to form a dry film layer capable of exhibiting antibacterial properties for a long period of time. In the ink composition, the silver oxide-containing phosphate glass particles may exist in a state in which the glass component and silver oxide are dissociated due to the elution of the Ag ions described above. , the ink composition contains silver oxide-containing phosphate glass particles.

The content of Ag ₂ O in the silver oxide-containing phosphate glass particles is preferably 0.2 to 5% by mass, more preferably 1 to 4% by mass, based on the mass of the silver oxide-containing phosphate glass particles. and more preferably 1.5 to 3% by mass.

Silver oxide-containing phosphate glass particles are phosphate glass particles that contain P ₂ O ₅ (diphosphorus pentoxide), which is a glass-forming component. This silver oxide-containing phosphate glass particle is a kind of oxide glass. In general, oxide glass is composed of a glass-forming component (an oxide that forms a network structure), which is a main component required for vitrification, and a modifying component (an oxide that modifies the network structure). Silicate glass when the glass-forming component is silicon dioxide (SiO ₂ ), borosilicate glass when the glass-forming component is boron oxide (B ₂ O ₃ ) + SiO ₂ , and only B ₂ O ₃ as the glass-forming component. If so, it is called a borate glass, and if the glass-forming component is _{P2O5 ,} it is called a phosphate glass. Modification moieties include, for example _, ZnO, CaO, MgO, _V2O5 , and _CeO2 .

The content of P ₂ O ₅ in the silver oxide-containing phosphate glass particles is preferably 30 to 80 mass % based on the mass of the silver oxide-containing phosphate glass particles. The above content of P ₂ O ₅ is preferably 30% by mass or more because the transparency of the silver oxide-containing phosphate glass particles is increased, Ag ions are easily eluted, and the mechanical strength is increased. preferable. On the other hand, the content of P ₂ O ₅ is preferably 80% by mass or less, and 75% by mass, because yellowing of the silver oxide-containing phosphate glass particles is easily suppressed and mechanical strength is increased. % or less, more preferably 70% by mass or less.

The silver oxide-containing phosphate glass particles preferably contain ZnO, CaO, and B ₂ O ₃ in addition to silver oxide (Ag ₂ O) and P ₂ O ₅ . ZnO (zinc oxide) serves as a modifying component in the phosphate glass particles. By containing ZnO as a modifying component, the silver oxide-containing phosphate glass particles tend to have a function of suppressing yellowing of the silver oxide-containing phosphate glass particles, and also have a function of enhancing antibacterial properties. Easy to have. From the viewpoint that ZnO tends to have the above functions, the content of ZnO in the silver oxide-containing phosphate glass particles is preferably 2 to 60% by mass based on the mass of the silver oxide-containing phosphate glass particles. It is preferably from 5 to 50% by mass, and even more preferably from 10 to 40% by mass.

CaO (calcium oxide) serves as a modifying component in the phosphate glass particles. By containing CaO as a modifying component in the silver oxide-containing phosphate glass particles, the heating temperature in producing the silver oxide-containing phosphate glass particles can be lowered, and yellowing occurs together with ZnO. tends to have a function of suppressing From these points of view, the content of CaO in the silver oxide-containing phosphate glass particles is preferably 0.1 to 15% by mass, based on the mass of the silver oxide-containing phosphate glass particles. It is more preferably 10% by mass, and even more preferably 2 to 7% by mass.

B ₂ O ₃ (boron oxide) basically functions as a glass-forming component in oxide glass, but in addition, in silver oxide-containing phosphate glass particles, it has the function of increasing the transparency and the function of Ag ions. It may have the function of increasing dissolution. From these points of view, the content of B ₂ O ₃ in the silver oxide-containing phosphate glass particles is preferably 0.1 to 15% by mass based on the mass of the silver oxide-containing phosphate glass particles. , more preferably 1 to 12% by mass, more preferably 5 to 10% by mass.

As described above, when the silver oxide-containing phosphate glass particles contain _Ag2O , _P2O5 , ZnO, CaO, and _B2O3 , the mass ratio of ZnO to CaO ( _ZnO / _CaO ) is It is preferably from 1.1 to 15, more preferably from 1.2 to 10, even more preferably from 1.5 to 8. Furthermore, when the silver oxide-containing phosphate glass particles contain Ag ₂ O, P ₂ O ₅ , ZnO, CaO, and B ₂ O ₃ , the glass composition is represented by the following compositional formula (1): is particularly preferred.
1/ _{3Ag2O .} ( _P2O5.ZnO ) _10. ( _2CaO.B2O3 ) _n (1 ₎
(n in the composition formula (1) represents a number from 1.1 to 1.4.)

The silver oxide-containing phosphate glass particles may contain other components in addition to the constituent components described above. Other components include, for example, CeO ₂ , MgO, Na ₂ O, Al ₂ O ₃ , K ₂ O, SiO ₂ and BaO. One or more of these may be contained in the silver oxide-containing phosphate glass particles.

In addition, the silver oxide-containing phosphate glass particles have silver oxide-containing phosphate glass particles as main particles, the main particles, and externally added particles provided around the main particles so as to cover the main particles. is preferably included. The content of the externally added particles in the silver oxide-containing phosphate glass particles is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, with respect to 100 parts by mass of the main particles. is more preferable, and 1 to 10 parts by mass is even more preferable.

Examples of materials for the externally added particles include amorphous silica such as precipitated silica, silica gel, and colloidal silica; resin beads such as acrylic resin, styrene resin, and polycarbonate resin; and titanium oxide, aluminum oxide, and oxide. Examples include zinc, lead oxide, tin oxide, and white carbon. These 1 types can be used individually or in combination of 2 or more types. Among these, the silver oxide-containing phosphate glass particles preferably contain amorphous silica as externally added particles.

Although the method for producing the silver oxide-containing phosphate glass particles described above is not particularly limited, for example, silver oxide-containing phosphate glass particles can be produced by a production method including steps A and B as described below is possible.

In step A, glass raw materials containing Ag ₂ O and P ₂ O ₅ (preferably further ZnO, CaO, and B ₂ O ₃ ) are mixed at a blending ratio that yields phosphate glass particles with a desired glass composition. After obtaining a raw material mixture, the raw material mixture is melted to obtain a glass melt. When mixing the glass raw materials, it is preferable to use a mixing machine (mixer) such as a universal stirrer (planetary mixer), an alumina porcelain grinder, a ball mill, or a propeller mixer. When obtaining the glass melt, the raw material mixture can be melted using, for example, a glass melting furnace. At that time, the melting temperature is preferably 600 to 1500° C., and the melting time is preferably 0.1 to 24 hours. .

Step B is a step of pulverizing the glass melt obtained in step A. In step B, it is preferable to perform a coarse pulverization step, a medium pulverization step, and a fine pulverization step as described below. The coarse pulverization step is a step of pulverizing the phosphate glass so that the average particle size is approximately 10 mm. As the coarse pulverization, it is usually preferable to perform water pulverization by injecting the glass melt into still water to obtain a predetermined average particle size. The intermediate pulverization step is a step of pulverizing the coarsely pulverized phosphate glass so that the average particle size is about 100 μm. As medium pulverization, primary medium pulverized powder of phosphate glass with an average particle size of about 10 mm and phosphate glass with an average particle size of about 1 mm, and phosphate glass with an average particle size of about 1 mm with an average particle size of about 1 mm are used. It is preferable to carry out secondary and medium pulverization into phosphate glass of about 100 μm. For example, a rotating roll or the like can be used for the primary medium pulverized powder. For the secondary and intermediate pulverization, for example, a rotary mill or the like can be used. The fine pulverization step is a step of pulverizing the phosphate glass after medium pulverization so that the average particle size becomes 0.1 to 50 μm. In the fine pulverization step, for example, a rotating mill, rotating roll, vibrating mill, ball mill, sand mill, jet mill, or the like can be used. Polyhedral phosphate glass particles can be obtained through the medium pulverization step and the fine pulverization step.

When obtaining the silver oxide-containing phosphate glass particles containing the main particles and the externally added particles, it is preferable to add the externally added particles to at least one of the above steps A and B. It is more preferable to add externally added particles in the fine pulverization step. This makes it easier to suppress reaggregation of the phosphate glass particles during pulverization.

The content of the inorganic particles in the ink composition is 1 to 15% by mass based on the mass of the solid content of the ink composition. The content of inorganic particles in the ink composition means the total content of silver oxide-containing phosphate glass particles and silver ion-supporting zirconium phosphate particles in the ink composition. For example, when the ink composition contains only silver oxide-containing phosphate glass particles among silver oxide-containing phosphate glass particles and silver ion-supporting zirconium phosphate particles, the ink composition contains inorganic particles. Amount refers to the total content of silver oxide-containing phosphate glass particles in the ink composition. Further, when the ink composition contains only the silver ion-supporting zirconium phosphate particles among the silver oxide-containing phosphate glass particles and the silver ion-supporting zirconium phosphate particles, the inorganic particles are contained in the ink composition. The amount means the total content of silver ion-supporting zirconium phosphate particles in the ink composition. When the ink composition contains both the silver oxide-containing phosphate glass particles and the silver ion-supporting zirconium phosphate particles, the content of the inorganic particles in the ink composition is the silver oxide content in the ink composition. It means the total content of phosphate glass particles and silver ion-supporting zirconium phosphate particles.

The content of the inorganic particles in the ink composition is preferably 1.5% by mass or more, more preferably 2% by mass or more, and 3% by mass or more, since the blocking resistance can be more easily improved. is more preferable. On the other hand, since it is easier to suppress curling, the content of the inorganic particles is preferably 14% by mass or less, more preferably 12% by mass or less, and further preferably 10% by mass or less. preferable.

Also, the content of the inorganic particles in the ink composition is preferably 2 to 20 parts by mass with respect to 100 parts by mass of the binder resin. The content of the inorganic particles is more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more, since the blocking resistance can be more easily improved. On the other hand, the content of the inorganic particles is more preferably 15 parts by mass or less, even more preferably 13 parts by mass or less, because curling can be more easily suppressed.

The content (% by mass) of the inorganic particles in the ink composition is preferably 0.3 to 5 times, more preferably 0.5 to 4 times, the content (% by mass) of the lubricant in the ink composition. 0.5 times is more preferable, and 0.7 to 4.5 times is even more preferable.

The ink composition contains a binder resin together with at least one inorganic particle selected from the silver oxide-containing phosphate glass particles and the silver ion-supporting zirconium phosphate particles. By including the binder resin in the ink composition, the components such as the inorganic particles contained in the ink composition can be fixed to the object on which the dry film layer of the ink composition is to be formed. The ink composition contains both an acrylic resin and a vinyl chloride-vinyl acetate copolymer resin as binder resins. By using an acrylic resin as the binder resin, it is easy to improve the physical properties (especially heat resistance) of the dry film layer. It is easy to improve blocking resistance.

Acrylic resin is a (meth)acrylic acid ester-based polymer in which a monomer component containing (meth)acrylic acid ester as a main component is polymerized as a polymerizable monomer, and the main structural unit is (meth)acrylic It contains a structural unit derived from an acid ester. Acrylic resins include, for example, homopolymers of (meth)acrylic acid esters; copolymers of multiple types of (meth)acrylic acid esters; (meth)acrylic acid esters, and copolymers with (meth)acrylic acid esters. Possible copolymers with other polymerizable monomers; urethane-modified acrylic resins; and silicone-modified acrylic resins. One or two or more of the above (meth)acrylic acid esters and other polymerizable monomers may be used. For the ink composition, one type of acrylic resin may be used alone, or two or more types may be used in combination. In this specification, the term "(meth)acryl" means that both the term "acryl" and "methacryl" are included.

Examples of (meth)acrylic acid esters include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, hexyl (meth)acrylate, and (meth)acrylic ester. (Meth)acrylic acid alkyl esters such as 2-ethylhexyl acid, lauryl (meth)acrylate, and stearyl (meth)acrylate; (meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate; (meth)acrylic acid (meth)acrylic acid aryl esters such as phenyl and naphthyl (meth)acrylate; (meth)acrylic acid hydroxyalkyl esters such as 2-hydroxyethyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate; Examples include, but are not limited to.

Examples of the other polymerizable monomers include styrene-based monomers such as styrene, α-methylstyrene, vinyltoluene, and derivatives thereof; (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, and unsaturated carboxylic acid-based monomers such as crotonic acid;

The acrylic resin preferably has a hydroxyl group and is preferably an acrylic polyol. The hydroxyl value of the acrylic resin is preferably 1 to 130 mgKOH/g, more preferably 10 to 120 mgKOH/g, even more preferably 50 to 110 mgKOH/g, and 80 to 105 mgKOH/g. is particularly preferred. As used herein, the hydroxyl value of a resin is the content of hydroxyl groups per 1 g of a sample of the resin expressed in terms of mg equivalent of KOH (unit: mgKOH/g), and is defined in JIS K0070-1992. Take the value measured according to the neutralization titration method.

Further, the acid value of the acrylic resin is preferably 0 to 30 mgKOH/g, more preferably 1 to 20 mgKOH/g, even more preferably 2 to 10 mgKOH/g. As used herein, the acid value of a resin is a value measured according to the neutralization titration method specified in JIS K0070-1992.

The glass transition point (Tg) of the acrylic resin is preferably 5 to 100°C, more preferably 10 to 70°C, even more preferably 15 to 40°C, and 20 to 30°C. is particularly preferred. As used herein, the Tg of a resin is a value determined by differential scanning calorimetry (DSC) in accordance with JIS K7121.

The weight average molecular weight (Mw) of the acrylic resin is preferably 10,000 to 300,000, more preferably 20,000 to 280,000, and more preferably 40,000 to 250,000. More preferably, it is particularly preferably from 80,000 to 220,000. In the present specification, the Mw of the resin is a standard polystyrene-equivalent value determined by a gel permeation chromatography (GPC) method.

Vinyl chloride-vinyl acetate copolymer resins include, for example, vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-vinyl acetate-vinyl alcohol copolymer resins, vinyl chloride-vinyl acetate-(meth)acrylic acid hydroxyalkyl ester copolymers. Polymer resins, vinyl chloride-vinyl acetate-dicarboxylic acid copolymer resins, and the like can be mentioned. One of them may be used alone, or two or more thereof may be used in combination. Among vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-vinyl acetate-vinyl alcohol copolymer resin is preferred.

The content of structural units derived from vinyl chloride in the vinyl chloride-vinyl acetate copolymer resin is preferably 50 to 98% by mass, more preferably 70 to 98% by mass, and more preferably 80 to 95% by mass. % is more preferred. Further, the content of structural units derived from vinyl acetate in the vinyl chloride-vinyl acetate copolymer resin is preferably 1 to 20% by mass, more preferably 1 to 10% by mass, and more preferably 1 to 10% by mass. More preferably, it is 5% by mass. The content of structural units derived from vinyl alcohol in the vinyl chloride-vinyl acetate copolymer resin is preferably 0 to 20% by mass, more preferably 1 to 20% by mass, and 2 to 15% by mass. % is more preferred.

The hydroxyl value of the vinyl chloride-vinyl acetate copolymer resin is preferably 20 to 200 mgKOH/g, more preferably 50 to 200 mgKOH/g, from the viewpoint that the desired ink composition can be easily obtained. More preferably 60 to 180 mgKOH/g.

The weight average molecular weight (Mw) of the vinyl chloride-vinyl acetate copolymer resin is preferably from 20,000 to 100,000, more preferably from 30,000 to 80, from the viewpoint of easily obtaining the desired ink composition. 000 is more preferred.

The ink composition may contain a binder resin other than the above acrylic resin and vinyl chloride-vinyl acetate copolymer resin. Examples of other binder resins include polyurethane-based resins, polyester-based resins, polyolefin-based resins, polyamide resins, ethylene-vinyl acetate-based copolymer resins, epoxy resins, and cellulose-based resins.

The form of the binder resin used in the ink composition is not particularly limited, and examples thereof include solids such as powder, dispersions such as emulsions and dispersions, solutions, and liquids such as liquid polymers. can be done. Among these, the acrylic resin described above is preferably in the form of a solution, and the vinyl chloride-vinyl acetate copolymer resin is preferably in the form of powder.

The total content of the acrylic resin and the vinyl chloride-vinyl acetate copolymer resin in the ink composition is preferably 50 to 98% by mass, based on the mass of the solid content of the ink composition, and preferably 60 to 98% by mass. It is more preferably 95% by mass, and even more preferably 65 to 90% by mass. The total content of the acrylic resin and the vinyl chloride-vinyl acetate copolymer resin means the resin content. For example, when the resin in the form of dispersion or solution is used, it means the content of the non-volatile content (solid content), which is the resin content, in the solid content of the ink composition.

Further, the ratio of the content (% by mass) of the acrylic resin to the content (% by mass) of the vinyl chloride-vinyl acetate copolymer resin in the ink composition is preferably from 2 to 7, and from 3 to 5. is more preferable.

The ink composition contains at least one selected from the group consisting of polyolefin waxes and fatty acid amides as a lubricant. By using a polyolefin wax and/or fatty acid amide as a lubricant to be contained in the ink composition, a synergistic effect is likely to occur due to the combination with the above-described inorganic particles, and a synergistic effect is likely to occur due to the combination with the above-described silver oxide-containing phosphate glass particles. effect is more likely to occur.

The ink composition may contain a lubricant other than polyolefin wax and fatty acid amide. Lubricants conventionally used in the field of ink can be used as the lubricant. Lubricants, including the above polyolefin waxes and fatty acid amides, include, for example, hydrocarbon-based, fatty acid-based, higher alcohol-based, fatty acid amide-based, metal soap-based, and ester-based lubricants. These 1 type(s) or 2 or more types can be used.

Examples of hydrocarbon-based lubricants include hydrocarbon-based waxes such as petroleum-derived hydrocarbon-based waxes and synthetic hydrocarbon-based waxes; and hydrocarbon-based oils such as mineral oil and liquid paraffin. The penetration of the hydrocarbon wax at 25° C. measured according to JIS K 2207 is preferably 1-20, more preferably 1-15. Examples of petroleum-derived hydrocarbon wax include paraffin wax and microcrystalline wax. Examples of synthetic hydrocarbon wax include Fischer-Tropsch wax, polyolefin wax (polyethylene wax, polypropylene wax, etc.), polytetrafluoroethylene wax, and the like.

Examples of fatty acid-based lubricants include stearic acid and behenic acid. Examples of higher alcohol-based lubricants include stearyl alcohol. Examples of fatty acid amide-based lubricants (fatty acid amides) include stearic acid amide, oleic acid amide, erucic acid amide, and methylenebisstearic acid amide. Examples of metal soaps include calcium stearate, magnesium stearate, lead stearate, and zinc stearate.

The content of the lubricant in the ink composition is preferably 0.5 to 10% by mass, more preferably 1 to 8% by mass, and more preferably 1 to 10% by mass, based on the mass of the solid content of the ink composition. More preferably, it is 5% by mass.

The form of the ink composition is not particularly limited as long as the ink composition contains the inorganic particles, the binder resin, and the lubricant described above. Examples of the form of the ink composition include solution, paste, and powder. The ink composition is preferably in the form of a solution, since it is easy to use at the time of use (at the time of coating, printing, etc.). The ink composition can contain the above-described inorganic particles, binder resin, and lubricant as solids.

When the ink composition is in the form of a solution, the solid content (nonvolatile content) of the ink composition is preferably 5 to 50% by mass, more preferably 10 to 50% by mass, based on the total mass of the ink composition. More preferably, 20 to 40% by mass is even more preferable.

Since the ink composition is preferably in the form of a solution as described above, it preferably further contains an organic solvent. Any organic solvent that dissolves or disperses the above-described components in the ink composition can be used. When a dispersion or solution is used as the binder resin, the dispersion medium in which the binder resin is dispersed or the solvent in which the binder resin is dissolved may be used as it is as the organic solvent component of the ink composition. can also Examples of organic solvents include ketone-based solvents, hydrocarbon-based solvents, ester-based solvents, ether-based solvents, glycol ether-based solvents, and alcohol-based solvents. can be used in combination.

Examples of ketone-based solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methylcyclohexanone, and diacetone alcohol. Examples of hydrocarbon solvents include aromatic hydrocarbon solvents such as toluene and xylene; aliphatic hydrocarbon solvents such as n-hexane, n-heptane, and n-octane; and cyclopentane, cyclohexane, and methylcyclohexane. , dimethylcyclohexane, and cyclooctane. Examples of ester solvents include methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, and isobutyl acetate. Examples of ether-based solvents include tetrahydrofuran, dioxane, diethyl ether, and methyl ethyl ether. Examples of glycol ether solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, and propylene glycol monomethyl ether. Examples of alcohol solvents include monohydric alcohols such as methanol, ethanol, n-propanol, isopropanol, and n-butanol; and polyhydric alcohols such as ethylene glycol, propylene glycol, and glycerin.

The content of the organic solvent in the ink composition is preferably 50 to 95% by mass, more preferably 50 to 90% by mass, and 60 to 80% by mass, based on the total mass of the ink composition. is more preferable.

The ink composition may contain coloring agents such as pigments and dyes, or may contain no coloring agents. An ink composition that does not contain a coloring agent can be used as a clear ink (also called a medium ink). By providing such a clear ink as a clear ink layer of the top coat on a base layer such as another colored ink layer, it is also possible to obtain a laminated sheet with good blocking resistance and suppressed curling. It is possible.

As the colorant, one or more of various pigments and dyes used in inks and paints can be used, and among them, pigments are preferred. Examples of pigments include titanium oxide, zinc oxide, lead oxide, zinc sulfide, aluminum, mica, titanium oxide-coated mica (pearl pigment), bronze powder, chrome vermilion, yellow lead, cadmium yellow, cadmium red, ultramarine blue, and Prussian blue. , red iron oxide, yellow iron oxide, iron black, and carbon black; extender pigments (inorganic pigments) such as barium sulfate, calcium carbonate, magnesium carbonate, aluminum hydroxide, silica, mica, kaolin, and clay; monoazo Pigments, disazo pigments, condensed azo pigments, phthalocyanine pigments, anthraquinone pigments, quinacridone pigments, isoindoline pigments, isoindolinone pigments, thioindigo pigments, pyrrolopyrrole pigments, azomethine azo pigments, perinone pigments organic pigments such as pigments and perylene-based pigments;

As long as the desired ink composition can be obtained, the ink composition may be used for the purpose of, for example, improving blocking resistance. Inorganic fillers other than zirconium acid particles) may be contained. Examples of inorganic fillers include silica, calcium carbonate, magnesium carbonate, talc, alumina, zirconia, barium titanate, antimony trioxide, titanium oxide, graphite, zinc oxide, precipitated calcium carbonate, gypsum, clay, diatomaceous earth, kaolin, Barium sulfate, aluminum stearate, barite powder and the like can be mentioned. These 1 type(s) or 2 or more types can be used.

The ink composition may further contain other additives as needed. Other additives include, for example, pigments, dyes, plasticizers, anti-blocking agents, dispersants, surfactants, anti-settling agents, leveling agents, anti-foaming agents, matting agents, pH adjusters, curing agents, cross-linking agents, agents, antioxidants, ultraviolet absorbers, light stabilizers, preservatives, antifungal agents, antirust agents, flame retardants, color developers, chelating agents, coupling agents, and the like. One or more of other additives can be used.

A mixture is prepared by blending the aforementioned specific inorganic particles, a binder resin, and a lubricant, which are essential components of the ink composition, and further blending an organic solvent, a colorant, other additives, etc. as necessary. Thus, an ink composition can be produced.

When preparing the mixture, it is preferable to mix each component using a disperser so that the inorganic particles and the like can be uniformly dispersed. Dispersers include, for example, paint shakers, ball mills, attritors, sand mills, bead mills, dyno mills, roll mills, ultrasonic mills, and high-pressure collision dispersers. One or two or more dispersers may be used. Further, the dispersion treatment may be performed once or multiple times using one type of dispersing machine, or the dispersion treatment may be performed multiple times using two or more types of dispersing machines in combination.

When using the ink composition in a technique such as coating or printing, when preparing the mixture or after preparing the mixture, an organic solvent for dilution may be added to the mixture to dilute it to a desired viscosity. preferable. As a result, the desired ink can be produced by diluting the ink composition with an organic solvent until the viscosity of the ink composition becomes suitable for the method of coating or printing.

The ink composition can be made into a solution form with an organic solvent and then applied or printed onto the substrate sheet to form a dry film layer. Therefore, it is possible to obtain a sheet body (coated matter or printed matter) including the substrate sheet and the dried film layer of the ink composition provided on the substrate sheet. Since the ink composition contains a specific amount of specific inorganic particles together with a specific binder resin and a lubricant, it is possible to obtain a sheet having good blocking resistance and suppressed curling.

The above sheet body is manufactured by a manufacturing method including applying or printing the ink composition on the base sheet and then removing the volatile components in the ink composition by drying to form a dry film layer of the ink composition. can do. The thickness of the dry film layer is preferably in the range of 0.1 to 20 μm, more preferably in the range of 0.5 to 10 μm, even more preferably in the range of 1 to 5 μm. The dry film layer can be provided on the whole or part of the base sheet, and may be provided on one side of the base sheet, may be provided on both sides, may be provided on the whole of one side, or may be provided on one side of the base sheet. may be provided in the department.

In forming a dry film layer of the ink composition on the substrate sheet, the method of applying or printing the ink composition is not particularly limited, and various known coating methods and printing methods can be used depending on the purpose. method can be used. Examples of the coating method include bar coater, gravure coater, comma coater, roll coater, air gun coating, and dip coating. Examples of printing methods include gravure printing, flexographic printing, offset printing, letterpress printing, and screen printing. Among these, the printing method is preferable, and the ink composition is more preferably for gravure printing or flexographic printing from the viewpoint that mass production is possible at low cost for a suitable base sheet to be described later. . In addition, the ink composition can form a dry film layer that can exhibit antibacterial properties by containing a specific amount of silver oxide-containing phosphate glass particles and/or silver ion-supporting zirconium phosphate particles. It is preferably for surface printing so as to make the most of its properties.

The base sheet is not particularly limited as long as it is film-like or sheet-like. Paper or a plastic film is suitable as the base sheet because the ink composition can improve blocking resistance and suppress curling. From the viewpoint of making full use of the properties of the ink composition, the thickness of the base sheet is preferably 5 to 200 μm, more preferably 5 to 100 μm, even more preferably 5 to 50 μm. , 5 to 30 μm.

Examples of paper used for the base sheet include art paper, coated paper, high-quality paper, gravure paper, Japanese paper, and synthetic paper. Examples of plastic films used for the base sheet include polyester films such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN); low-density polyethylene (LDPE), linear low-density Polyolefin films such as polyethylene (LLDPE), high density polyethylene (HDPE), and polypropylene (PP); cellulose films such as cellophane; polystyrene (PS) films; ethylene-vinyl acetate copolymer resin films; ethylene-vinyl alcohol copolymer resins Films; polyamide films such as nylon (Ny) films; polycarbonate films; polyimide films; polyvinyl chloride films; For example, both stretched and unstretched plastic films can be used, such as biaxially stretched PP films and unstretched PP films. A base material provided with a metal vapor deposition layer such as aluminum vapor deposition, or a base material provided with a transparent vapor deposition layer of alumina, silica or the like can also be used. Furthermore, the surface of the base material may be subjected to various surface treatments such as corona discharge treatment, plasma treatment, flame treatment, solvent treatment, and coating treatment, as well as various decorations such as printing using colored ink. good.

In the sheet body described above, a resin layer may be further provided on the side of the base sheet on which the dried film layer of the ink composition is provided, thereby forming a sheet body having a laminated structure (laminated sheet). That is, the sheet body may include a substrate sheet, a resin layer, and a dry film layer of an ink composition provided between the substrate sheet and the resin layer. It is preferable to have an adhesive layer or an anchor coating agent layer between the dry film layer of the ink composition and the resin layer. As the resin layer, it is possible to use the resin of the material described for the plastic film that can be used as the base sheet. As a method for laminating the resin layer, there is a dry lamination method in which a plastic film (resin layer) is laminated via an adhesive layer on the dry film layer provided on the base sheet, or a dry lamination method in which an anchor coating agent layer is added as necessary. A known lamination method such as an extrusion lamination method in which a molten resin is laminated via an intervening layer can be used. The thickness of the resin layer is not particularly limited, and is, for example, preferably 1 to 300 μm, more preferably 5 to 200 μm, even more preferably 10 to 100 μm.

The use of the sheet body is not particularly limited. Moreover, the form of the sheet body can take various forms such as a film form, a sheet form, a bag form, a box form, a pouch form, a pack form, and the like, depending on the application. Furthermore, the sheet body may have a configuration provided with a pressure-sensitive adhesive layer or an adhesive layer (for example, tape, liner, label, sticker, etc.) depending on the application. Examples of applications for sheet materials include packaging materials (for example, packaging materials for food, beverages, cosmetics, pharmaceuticals, medical materials, and electrical and electronic parts), electrical and electronic parts, and various sanitary products. Goods can be mentioned.

In addition, as described above, an embodiment of the present invention can have the following configuration.
[1] An ink composition comprising:
binder resin; inorganic particles of at least one of phosphate glass particles containing silver oxide and zirconium phosphate particles supporting silver ions; and a lubricant,
The binder resin includes a combination of acrylic resin and vinyl chloride-vinyl acetate copolymer resin,
The inorganic particles have an average particle size of 0.1 to 20 μm,
The content of the inorganic particles is 1 to 15% by mass based on the mass of the solid content of the ink composition,
The ink composition, wherein the lubricant contains at least one selected from the group consisting of polyolefin waxes and fatty acid amides.
[2] The ink composition according to [1] above, which contains at least the phosphate glass particles as the inorganic particles.
[3] The ink composition according to [2] above, wherein the phosphate glass particles have an average particle size of 0.3 to 15 μm.
[4] The ink composition according to [2] or [3] above, wherein the phosphate glass particles contain ZnO, CaO, and B ₂ O ₃ in addition to the silver oxide and P ₂ O ₅ .
[5] The ink composition according to any one of [2] to [4] above, wherein the glass composition of the phosphate glass particles is represented by the following compositional formula (1).
1 _{/ 3Ag2O} .( _P2O5.ZnO ) _10. ( _2CaO.B2O3 ) _n (1 ₎
(n in the composition formula (1) represents a number from 1.1 to 1.4.)
[6] The ink composition according to any one of [1] to [5] above, wherein the content of the inorganic particles is 2 to 20 parts by mass with respect to 100 parts by mass of the binder resin.
[7] The total content (% by mass) of the acrylic resin and the vinyl chloride-vinyl acetate copolymer resin is 50 to 98% by mass based on the solid content of the ink composition,
The ink composition according to any one of [1] to [6] above, wherein the content (% by mass) of the lubricant is 0.5 to 10% by mass based on the mass of the solid content of the ink composition. .
[8] The content (% by mass) of the inorganic particles in the ink composition is 0.3-5 times the content (% by mass) of the lubricant in the ink composition [ 1] to the ink composition according to any one of [7].
[9] The ink composition according to any one of [1] to [8] above, which further contains an organic solvent.
[10] The ink composition according to any one of the above [1] to [9], which is for gravure printing or flexographic printing.
[11] A sheet body comprising a base sheet and a dry film layer of the ink composition according to any one of [1] to [10] provided on the base sheet.

EXAMPLES Hereinafter, the matte coating agent according to one embodiment of the present invention will be described in more detail with reference to examples and comparative examples, but the matte coating agent is not limited to the following examples.

<Preparation of ink composition>
1. Binder Resins The following binder resins were used.
(1) Acrylic resin 1; trade name "Acrynal #6600" manufactured by Toei Kasei Co., Ltd. (acrylic polyol; hydroxyl value (solid value): 100 mg KOH / g, acid value (solid value): 4.3 mg KOH /g, Tg: 25 ° C., Mw: 200000, Solid content: 35% by mass, Containing solvent: ethyl acetate)
(2) Acrylic resin 2; trade name "Acryt 6BF-400" manufactured by Taisei Fine Chemical Co., Ltd. (acrylic polyol; hydroxyl value (solid value): 58.2 mg KOH / g, acid value (solid value): 4.9 mg KOH / g, Tg: 24 ° C., Mw: 46000, solid content: 51% by mass, solvent contained: ethyl acetate)
(3) Acrylic resin 3; trade name "Acryt 6KW-083E" manufactured by Taisei Fine Chemical Co., Ltd. (acrylic polyol; hydroxyl value (value in solid): 19.6 mg KOH / g, acid value (value in solid): 5.9 mg KOH / g, Tg: 40 ° C., Mw: 25000, Solid content: 51% by mass, Containing solvent: ethyl acetate)
(4) Vinyl chloride-vinyl acetate copolymer resin 1 (hereinafter referred to as VC-VAc copolymer resin 1); trade name "Solbin A" manufactured by Nissin Chemical Industry Co., Ltd. (vinyl chloride-vinyl acetate-vinyl alcohol Polymerized resin; vinyl chloride (VC) content: 92% by mass, vinyl acetate (VAc) content: 3% by mass, vinyl alcohol (VA) content: 5% by mass, hydroxyl value (solid value): 69. 3 mgKOH/g, Tg: 76°C, Mw: 73000, Mn: 35000)
(5) Vinyl chloride-vinyl acetate copolymer resin 2 (hereinafter referred to as VC-VAc copolymer resin 2); Nissin Chemical Industry Co., Ltd. trade name "Solbin TA3" (vinyl chloride-vinyl acetate-hydroxyalkyl acrylate Copolymer resin; vinyl chloride (VC) content: 83% by mass, vinyl acetate (VAc) content: 4% by mass, hydroxyalkyl acrylate content: 13% by mass, hydroxyl value (solid value): 63 mgKOH/g , Tg: 65°C, Mw: 64000, Mn: 32000)

2. Lubricants The following lubricants were used.
(1) Polyethylene wax; trade name "High Wax 220P" manufactured by Mitsui Chemicals, Inc. (molecular weight (viscosity method): 2000, density (JIS K7112): 920 kg/m ³ , degree of crystallinity (X-ray diffraction method), melting point (DSC method): 110°C, softening point (JIS K2207): 113°C, penetration (JIS K2207): 1.3 mm)
(2) Fatty acid amide; trade name "ALFLOW S-10" manufactured by NOF Corporation (stearic acid amide, transparent melting point: 100-105°C, acid value: 2 mgKOH/g or less)

3. Inorganic Fillers Inorganic fillers 1 to 6 below were used.
(1) Inorganic fillers 1 to 3; silver oxide-containing phosphate glass particles (manufactured by Koa Glass Co., Ltd.) having an average particle size of 1 μm (inorganic filler 1), 3 μm (inorganic filler 2), or 10 μm (inorganic filler 3) Product name "Million Guard"; 97% by mass or more of silver-containing phosphate glass powder, less than 3% by mass of amorphous silica-based grinding aid, chemical properties (glass component notation): 1/3 Ag ₂ O (P _{2 O5.ZnO ) 10.} ( _2CaO.B2O3 ) _1.1-1.4 )
(2) Inorganic filler 4: Silver ion-supporting zirconium phosphate particles having an average particle size of 0.9 μm (trade name “Novaron AG300” manufactured by Toagosei Co., Ltd.)
(3) Inorganic filler 5: Silver ion-supporting zirconium phosphate particles having an average particle size of 1.3 μm (trade name “Novaron AGZ330” manufactured by Toagosei Co., Ltd.)
(4) Inorganic filler 6: Gel type silica (trade name “NIPGEL AZ204” manufactured by Tosoh Silica Co., Ltd., average particle size: 2.9 μm)

4. Other Additives The following additives were used.
· Plasticizer; N-ethyl-o/p-toluenesulfonamide

5. Organic solvent The following mixed solvent was used.
Mixed solvent; mixed solvent of ethyl acetate (65.4% by mass)/methyl ethyl ketone (20.2% by mass)/propyl acetate (14.4% by mass)

(Test Examples 1 to 17)
After mixing each component (unit: parts by mass) shown in the upper part of Tables 1 to 3, the mixture was kneaded with a paint shaker to prepare an ink composition. The ink compositions obtained in Test Examples 1 to 17 are described as ink compositions 1 to 17, respectively. The amounts (unit: parts by mass) of binder resins and inorganic fillers shown in the upper part of Tables 1 to 3 are converted values of solid content or active ingredients. For example, when a solution of the binder resin is used, the amount of the binder resin means the resin content, that is, the amount of solid content in the solution. Further, for example, the amounts of inorganic fillers 1 to 6 mean the amounts of inorganic compounds that are active ingredients (main ingredients) in the inorganic fillers. In the middle of Tables 1 to 3, the content (% by mass) of inorganic fillers 1 to 6 in the solid content of the ink composition, the content (parts by mass) of inorganic fillers 1 to 6 with respect to 100 parts by mass of the binder resin, and the ratio (fold) of the content (% by mass) of the inorganic fillers 1 to 6 to the content (% by mass) of the lubricant.

<Production of sheet body>
(Test Examples 1 to 17)
In Test Examples 1 to 17, ink compositions 1 to 17 were used to produce sheet bodies in which a dry film layer of the ink composition was provided on a base sheet. Specifically, the ink composition was applied to the treated surface of a corona discharge-treated PET film (manufactured by Toyobo Co., Ltd., trade name "Toyobo E5102", thickness: 12 µm) using a bar coater #10 (manufactured by RD SPECIALITIES). ), and then dried at 40° C. for 10 minutes to form a dry film layer having a thickness of about 5 μm to obtain a sheet.

<Evaluation>
Using the sheet bodies produced in Test Examples 1 to 17, blocking resistance and curl resistance were evaluated as described below. Evaluation results are shown in the lower part of Tables 1 to 3.

(Blocking resistance)
A sample sheet was prepared by cutting a sheet body into a size of 5 cm in width and 5 cm in length, and the dry film layers of the ink composition of the two sample sheets were overlapped with each other, and a load of 4 kgf/cm ² was applied. and placed in a constant temperature bath at 40° C. for 24 hours. After that, the blocking resistance was evaluated according to the following evaluation criteria with respect to peeling resistance depending on the degree of peeling of the dry film layer and sticking between the dry film layers when the two sample sheets were peeled off. A and B in the following evaluation criteria were judged to have good blocking resistance.
A: There is no peeling of the dry film layer and almost no peeling resistance.
B: There is no peeling of the dry film layer, and the peeling resistance is slight.
C: Slight peeling of the dry film layer is observed, and there is peeling resistance.
D: There is a large peeling resistance.

(curl height)
A sample sheet having a width of 2.5 cm and a length of 15 cm was cut from the sheet body and placed in an environment of 25° C. and 60% RH for 1 hour. After that, the sample sheet was placed on a flat table with the curled side facing up, and how much the both ends of the sample sheet were lifted from the table (curl height) was measured. Three sample sheets are prepared for each test example, and the left and right sides of both ends in the width direction of the sample sheet are measured (3 sheets x 2 (left and right) = 6 points), and the average value of those measured values was calculated as the curl height.

(Curl resistance)
Based on the curl height in each test example, the curl suppressing effect (curl resistance) was evaluated according to the following evaluation criteria. When the curl height was less than 3 mm, it was indicated as "○" and it was judged that the curl resistance was good.
◯: The curl height is less than 3 mm.
x: The curl height is 3 mm or more.

In Test Examples 1 to 13, acrylic resin, vinyl chloride-vinyl acetate copolymer resin, and at least one lubricant selected from polyethylene wax and fatty acid amide were contained, and the average particle size was 0.1 to 20 μm. By using an ink composition containing a specific amount of inorganic particles of at least one of silver oxide-containing phosphate glass particles and silver ion-supporting zirconium phosphate particles within the range, blocking resistance and curl resistance are improved. It was confirmed that a sheet body having good properties could be obtained.

Claims (11)

An ink composition comprising:
binder resin; inorganic particles of at least one of phosphate glass particles containing silver oxide and zirconium phosphate particles supporting silver ions; and a lubricant,
The binder resin includes a combination of acrylic resin and vinyl chloride-vinyl acetate copolymer resin,
The inorganic particles have an average particle size of 0.1 to 20 μm,
The content of the inorganic particles is 1 to 15% by mass based on the mass of the solid content of the ink composition,
The ink composition, wherein the lubricant contains at least one selected from the group consisting of polyolefin waxes and fatty acid amides. 2. The ink composition according to claim 1, comprising at least the phosphate glass particles as the inorganic particles. The ink composition according to claim 2, wherein the phosphate glass particles have an average particle size of 0.3 to 15 µm. The ink composition according to _claim 2 or ₃ , wherein the phosphate glass particles contain ZnO, CaO and _B2O3 in addition to the silver oxide and _P2O5 . The ink composition according to any one of claims 2 to 4, wherein the glass composition of the phosphate glass particles is represented by the following compositional formula (1).
1 _{/ 3Ag2O} .( _P2O5.ZnO ) _10. ( _2CaO.B2O3 ) _n (1 ₎
(n in the composition formula (1) represents a number from 1.1 to 1.4.) The ink composition according to any one of claims 1 to 5, wherein the content of the inorganic particles is 2 to 20 parts by mass with respect to 100 parts by mass of the binder resin. The total content (% by mass) of the acrylic resin and the vinyl chloride-vinyl acetate copolymer resin is 50 to 98% by mass based on the mass of the solid content of the ink composition,
The ink composition according to any one of claims 1 to 6, wherein the content (% by mass) of the lubricant is 0.5 to 10% by mass based on the mass of the solid content of the ink composition. The content (% by mass) of the inorganic particles in the ink composition is 0.3 to 5 times the content (% by mass) of the lubricant in the ink composition. The ink composition according to any one of . The ink composition according to any one of claims 1 to 8, further comprising an organic solvent. The ink composition according to any one of claims 1 to 9, which is for gravure printing or flexographic printing. A sheet body comprising a substrate sheet and a dry film layer of the ink composition according to any one of claims 1 to 10 provided on the substrate sheet.