JP2022133633A - Overprint varnish, printed matter, paper substrate or plastic substrate - Google Patents

Abstract

To provide an overprint varnish that has high antibacterial and antivirus effect and prevents printed matter from yellowing over time.SOLUTION: Provided are an overprint varnish, which is an overprint varnish containing a rosin-modified phenolic resin-containing varnish, a dryer and wax, and contains at least one inorganic solid acid selected from the group consisting of an inorganic phosphoric acid compound, an inorganic silicic acid compound and an inorganic oxide by 0.5 to 15 mass%, and a paper substrate or plastic substrate using the same. The inorganic solid acid preferably is an inorganic phosphoric acid compound.SELECTED DRAWING: None

Description

The present invention relates to an overprint varnish that dries to form a varnish film.

Overprint varnish (also referred to as overcoat varnish, hereinafter sometimes referred to as OP varnish) is used after printing for the purpose of improving the glossiness of the printed matter and protecting the film of the printed matter. Specifically, colorless and transparent OP varnish is printed after each color of printing ink is printed. As the OP varnish, a solvent type OP varnish is known which contains an organic solvent and is dried to form a varnish film. (See Patent Document 1, for example)

On the other hand, in recent years, there is a demand for the addition of functionality to the surface of various substrates, and it is necessary to improve the surface properties of not only printed matter, but also plastic materials, molded products, paper substrates, film substrates, packaging materials, etc. there is
Especially in recent years, in addition to physical functionality such as gloss improvement and film protection, hygienic functions such as antibacterial and antiviral functions are also desired. There is an urgent need for antiviral (virus inactivating) measures as measures against viral infections.

As an OP varnish composition having antiviral performance, for example, an OP varnish composition characterized by containing polytetrafluoroethylene particles and an antibacterial agent in OP varnish is known (see, for example, Patent Document 2). . However, the zeolite-based inorganic antibacterial agent used in Patent Document 2 has a large antibacterial effect but a small antiviral effect, and there is a problem that the printed matter tends to yellow over time.

JP 2019-94443 A JP-A-11-80643

The problem to be solved by the present invention is to provide an overprint varnish that has a large antibacterial and antiviral effect and prevents printed matter from yellowing over time.

The present inventors have solved the problem by providing an overprint varnish containing a specific amount of at least one inorganic solid acid selected from the group consisting of inorganic phosphoric acid compounds, inorganic silicic acid compounds and inorganic oxides.

That is, the present invention provides an overprint varnish containing a varnish containing a rosin-modified phenolic resin, a drier, and wax, wherein at least one selected from the group consisting of inorganic phosphoric acid compounds, inorganic silicic acid compounds and inorganic oxides. An overprint varnish containing 0.5 to 15% by mass of three inorganic solid acids is provided.

The present invention also provides an overprint varnish containing 0.5 to 15% by mass of an inorganic phosphoric acid compound as the inorganic solid acid.

Further, according to the present invention, the varnish is a varnish containing a rosin-modified phenolic resin and a rosin-ester resin, wherein the mass ratio of the rosin-modified phenolic resin:rosin-ester resin is 7:3 to 3:7. to provide an overprint varnish as described in .

The present invention also provides a printed matter comprising a substrate and a coating of the above-described overprint varnish disposed on the substrate.

The present invention also provides a paper substrate or a plastic substrate obtained by applying the above-described overprint varnish to a paper substrate or a film.

The present invention also provides containers and packaging materials using the above-described paper base material or plastic base material.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to obtain an overprint varnish that has a large antibacterial and antiviral effect and prevents printed matter from yellowing over time.

(overprint varnish)
The overprint varnish of the present invention is not particularly limited except that it contains an inorganic solid acid, which will be described later. Generally, a varnish containing a varnish, a drier and a wax, and a rosin-modified phenolic resin is used as the varnish. Also, organic solvents or vegetable oils are used for the purpose of adjusting the viscosity.

Rosin-modified phenolic resins are obtained by, for example, resols having an average number of nuclei of 1.5 to 3.0 obtained by the heat reaction of formaldehyde and/or paraformaldehyde and phenols, and by reacting rosins with polyhydric alcohols. A resin obtained by reacting the obtained rosin ester resin, or a resin obtained by reacting a resole having an average number of nuclei of 1.5 to 3.0 with a rosin and then esterifying it with a polyhydric alcohol. can be used.

Phenols used for preparing resol include, for example, phenol, cresol, amylphenol, p-tertiarybutylphenol, p-octylphenol, p-nonylphenol, p-dodecylphenol, bisphenol A, etc. Among them, p-tertiary It is preferable to use an alkylphenol having a substituent having 4 to 12 carbon atoms at the para position, such as butylphenol, p-octylphenol, p-nonylphenol and p-dodecylphenol.

Conventionally known rosins can be used without any particular limitation. Examples thereof include gum rosin, wood rosin, tall oil rosin, polymerized rosin, acid-modified rosin, and products obtained by refining these rosins by distillation or the like.

When acid-modified rosin is used, it is preferable to use a dibasic acid or its anhydride as a compound used for modifying rosin. Examples include fumaric acid, maleic acid, maleic anhydride, adipic acid, itaconic acid, phthalic anhydride, isophthalic acid, terephthalic acid, and trimellitic anhydride, among which fumaric acid, maleic acid, and maleic anhydride are preferably used.

Polyhydric alcohols include, for example, glycerin, diglycerin, trimethylolethane, trimethylolpropane, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, pentaerythritol, dipentaerythritol, sorbitol, etc. Among them, glycerin and pentaerythritol are preferably used.

The weight average molecular weight of the rosin-modified phenolic resin is not particularly limited, but is generally preferably 15,000 or more, more preferably 30,000 or more. Moreover, it is preferable that it is 150,000 or less. In addition, the weight average molecular weight in this specification is a value measured by gel permeation chromatography (GPC) under the following conditions.

Measuring device; HLC-8320GPC manufactured by Tosoh Corporation
Column; TSKgel 4000HXL, TSKgel 3000HXL, TSKgel 2000HXL, TSKgel 1000HXL manufactured by Tosoh Corporation
Detector; RI (differential refractometer)
Data processing; Multi-station GPC-8020modelII manufactured by Tosoh Corporation
Measurement conditions; Column temperature 40°C
Solvent Tetrahydrofuran
Flow rate 0.35 ml/min Standard; Monodisperse polystyrene Sample; 0.2% by mass tetrahydrofuran solution in terms of resin solid content filtered through a microfilter (100 μl)

The rosin-modified phenol resin preferably has a softening point of 150° C. or higher, more preferably 160° C. or higher. Also, the softening point is preferably 200° C. or lower. The softening point in this specification is measured by the ring and ball method in accordance with JIS K5601-2-2. Specifically, a brass ring filled with a sample is held horizontally in a glycerin bath, and the sample is A steel ball of constant weight was placed in the center, and the temperature of the bath was raised at a constant rate. Softening point.

As other resins that can be used in combination with the rosin-modified phenolic resin, conventionally known resins can be used without particular limitation. Rosin resin, rosin-modified phenolic resin, rosin ester resin, petroleum resin, acrylic resin, polyester, alkyd resin, petroleum-resin-modified rosin/phenolic resin, petroleum-resin-modified rosin ester, petroleum-resin-modified alkyd resin, alkyd-resin-modified rosin/phenolic resin , alkyd resin-modified rosin ester, acrylic-modified rosin/phenolic resin, acrylic-modified rosin ester, urethane-modified rosin/phenolic resin, urethane-modified rosin ester, urethane-modified alkyd resin, epoxy-modified rosin/phenolic resin, epoxy-modified rosin ester, epoxy-modified Alkyd resins and the like are exemplified. These resins may be used alone, or two or more of them may be used in combination. Combined use of a rosin-modified phenol resin and a rosin ester resin is preferable because printability can be imparted more effectively. The total resin amount of the rosin-modified phenol resin and the rosin ester resin is preferably 25% by mass or more, more preferably 30% by mass or more, in the overprint varnish.
The mass ratio of rosin-modified phenol resin:rosin ester resin is preferably 7:3 to 3:7, more preferably 65:35 to 35:65, and 55:45 to 45:55. A range is more preferable.

Vegetable oils include non-drying oils such as castor oil, peanut oil, and olive oil, semi-drying oils such as soybean oil, cottonseed oil, rapeseed oil, sesame oil, and corn oil, drying oils such as linseed oil, perilla oil, and tung oil, and recycled vegetable oils. , plant-derived components such as plant esters, and the like.

Recycled vegetable oils can also be used as vegetable oils. Recycled vegetable oil is vegetable oil that has been recovered from oils used for cooking or the like and regenerated. As the regenerated vegetable oil, an oil that has been regenerated with a water content of 0.3% by mass or less, an iodine value of 90 or more, and an acid value of 3 or less is preferable, and an iodine value of 100 or more is more preferable. By reducing the water content to 0.3% by mass or less, it is possible to remove impurities that affect the emulsification behavior of the ink, such as salt contained in the water. In other words, it is possible to improve the oxidative polymerization property, and furthermore, by selecting and regenerating the vegetable oil having an acid value of 3 or less, it is possible to suppress excessive emulsification of the ink. Examples of methods for regenerating the recovered vegetable oil include filtration, removal of precipitates by standing, and decolorization using activated clay or the like.

Examples of fatty acid esters include soybean oil fatty acid methyl ester, soybean oil fatty acid butyl ester, soybean oil fatty acid isobutyl ester, soybean oil fatty acid 2-ethylhexyl ester, linseed oil fatty acid butyl ester, linseed oil fatty acid isobutyl ester, and tall oil fatty acid butyl ester. Ester, tall oil fatty acid 2-ethylhexyl ester, tall oil octyl ester, tall oil fatty acid pentaerythritol ester, palm oil fatty acid methyl ester, palm oil fatty acid butyl ester, palm oil fatty acid isobutyl ester, palm oil fatty acid 2-ethylhexyl ester, castor oil Examples include fatty acid methyl ester, castor oil fatty acid butyl ester, castor oil fatty acid isobutyl ester, and castor oil fatty acid 2-ethylhexyl ester.

A petroleum-based solvent is usually used as the organic solvent. As the petroleum solvent, a hydrocarbon solvent having 6 to 20 carbon atoms is preferably used. Specifically, paraffinic solvents such as n-pentane, isopentane, n-hexane, 2-methylpentane, n-heptane, n-octane, and trimethylpentane; naphthenes such as cyclohexane, cyclohexylmethane, octadecylcyclohexane, and methylisopropylcyclohexane; Examples of solvent include "AF Solvent No. 4", "AF Solvent No. 5", "AF Solvent No. 6" and "AF Solvent No. 7" manufactured by ENEOS Corporation.

Chelating agents include, for example, derivatives of aluminum n-butoxide, aluminum-iso-butoxide and aluminum-sec-butoxide, wherein one of the n-butoxy, iso-butoxy and sec-butoxy groups is Examples include compounds substituted with ethyl acetate or methyl acetoacetate.

As the dryer, conventionally known ones can be used without particular limitation. For example, metals such as cobalt, manganese, lead, iron, zinc, calcium, cerium, and rare earths, and carboxylic acids such as octylic acid, naphthenic acid, neodecanoic acid, tung acid, linseed acid, soybean oil acid, and resin acid. Salts, that is, metal soaps, or borates with metals such as cobalt, manganese, lead, iron, zinc, calcium, cerium and rare earths can be used. These dryers may be used alone, or two or more of them may be used in combination.

Examples of waxes include natural waxes such as carnauba wax, paraffin wax and microcrystalline wax, synthetic waxes such as Fischer-Tropsch wax, polyethylene wax, polypropylene wax, polytetrafluoroethylene wax, polyamide wax and silicone compounds. These waxes may be used alone, or two or more of them may be used in combination. Fischer-Tropsch wax, polyethylene wax, and composites thereof are preferably used. By using these composites, good abrasion resistance can be obtained. The wax content in the overprint varnish is preferably 1% by mass or more, more preferably 3% by mass or more.

The overprint varnish of the present invention may contain a matting agent in the overprint varnish. By applying such an overprint varnish composition, a matte effect can be imparted to the printed matter. Examples of matting agents include resin particles such as vinyl chloride resins, urea resins, polyethylene resins, polypropylene resins, polystyrene resins, acrylic resins, and polyamide resins. They can be used in combination. Vinyl chloride-based resins and urea-based resins are preferable because they can effectively impart a matting effect. The amount of the matting agent in the overprint varnish is preferably 15% by mass or more, and preferably 30% by mass or less.

Starch can also be preferably used. By using starch in addition to the wax, the set-off resistance can be improved. It is preferable to use one having an average particle diameter D50 of 10 μm or more and 20 μm or less. In the overprint varnish, the total content of particles having an average particle size D50 of 2 μm or more and 7 μm or less and starch having an average particle size D50 of 10 μm or more and 20 μm or less is preferably 1% by mass or more, and 10% by mass or less. Preferably.

Extender pigments can also be preferably used. For example, one or two or more of known clays such as clay such as pyroxene clay, talc, barium sulfate, calcium carbonate, heavy calcium carbonate, barium carbonate, silica, bentonite, and titanium oxide can be used. By containing the extender pigment, the overprint varnish can be set faster, and set-off can be suppressed more effectively. On the other hand, the inclusion of extender pigments reduces the gloss of the overprint varnish. Therefore, the content of the extender pigment may be adjusted according to the effect (gloss/matte) desired to be imparted to the printed matter by the overprint varnish and the degree thereof. Since the extender pigment has the effect of reducing the glossiness of the printed matter, it is desirable to appropriately adjust the amount added according to the desired design.

If there is a risk of scumming during coating, the overprint varnish of the present invention may contain phosphoric acid, an ammonium phosphoric acid, an alkali metal phosphoric acid, or an alkaline earth metal dihydrogen phosphoric acid. , citric acid, ammonium salts of citric acid, alkali metal salts of citric acid, and magnesium salts of citric acid. The content of the antifouling agent particles is preferably 0.01% by mass or more and 0.5% by mass or less, more preferably 0.01% by mass or more and 0.2% by mass or less, of the overprint varnish. The amount of dampening water used during coating can be suppressed, setting delay can be prevented, and set-off resistance can be improved.

The overprint varnish of the present invention may contain other auxiliary agents such as anti-skinning agents, viscosity modifiers, dispersants, antifouling agents other than those mentioned above, emulsification modifiers and antioxidants. As these auxiliary agents, conventionally known ones can be suitably used.

(At least one inorganic solid acid selected from the group consisting of inorganic phosphoric acid compounds, inorganic silicic acid compounds and inorganic oxides)
At least one inorganic solid acid selected from the group consisting of inorganic phosphoric acid compounds, inorganic silicic acid compounds and inorganic oxides used in the present invention (hereinafter sometimes referred to as "inorganic solid acid used in the present invention") is Acts as an antibacterial antiviral agent. The inorganic solid acid used in the present invention is contained in the overprint varnish in an amount of 0.5 to 15% by mass. If the amount is less than 0.5% by mass, the desired antibacterial and antiviral properties cannot be obtained, while if the amount exceeds 15% by mass, the printed matter will turn yellow and the glossiness of the printed matter will decrease. In addition, it is preferable to contain 3 to 10% by mass.

(inorganic solid acid)
The inorganic solid acid used in the present invention is an inorganic solid acid having antibacterial and antiviral properties. It preferably has a point. This acid site concentration is preferably more than 0.005 mmol/g in order to preferably exhibit the effect of inactivating viruses (hereinafter referred to as "antiviral effect").

The inorganic solid acid is preferably an inorganic compound having a structure in which proton-donating or proton-accepting substituents are arranged on the surface with which the virus comes into contact. Specific examples of the inorganic solid acid include zirconium phosphate, hafnium phosphate, phosphate compounds of titanium group elements such as titanium phosphate, and inorganic phosphate compounds such as aluminum phosphate and hydroxyapatite (phosphate minerals); Inorganic silicate compounds such as magnesium silicate, silica gel, aluminosilicate, sepiolite (hydrous magnesium silicate), montmorillonite (silicate mineral), zeolite (aluminosilicate); alumina, titania, hydrous titanium oxide, etc. , and inorganic oxides having an acid point concentration of 0.005 mmol/g or more. Among these, α-type or γ-type zirconium phosphate, α-type or γ-type titanium phosphate, amorphous magnesium silicate, active titanium oxide, etc. have an acid site concentration of more than 0.005 mmol/g, and are suitable for use in the present invention. It is preferable as an inorganic solid acid contained in antiviral agents. Among them, inorganic phosphoric acid compounds are preferred. The inorganic phosphoric acid compound is preferably contained in the overprint varnish in an amount of 0.5 to 15% by mass.

The inorganic solid acid used in the present invention can contain silver or copper, or both. The inorganic solid acid used in the present invention may contain an inorganic solid acid having silver ions (silver atoms) or copper ions (copper atoms) in its structure. , a mixture with an inorganic solid acid that does not contain silver and copper. Antiviral agents containing silver or copper have excellent antiviral effects. The total content of silver or copper, or a compound thereof in such an antiviral agent is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and still more preferably 1% by mass or more. be. Examples of the inorganic solid acid having silver ions (silver atoms) or copper ions (copper atoms) in its structure include silver zirconium phosphate and copper zirconium phosphate.

The inorganic solid acid used in the present invention is preferably in powder form so that it can be processed into various materials and forms. The powdery inorganic solid acid preferably has an average particle size of 0.01 to 50 μm, more preferably 0.1 to 20 μm. A powder having an average particle size of 0.01 μm or more is difficult to agglomerate and thus has the advantage of being easy to handle.
The average particle diameter can be measured with a laser diffraction particle size distribution analyzer or the like, and is a median diameter analyzed on a volume basis.

Although the color tone of the inorganic solid acid used in the present invention is not limited, it is preferably white or a light color with high brightness so that it can be processed into various materials and forms. The lightness is preferably 80 or more, more preferably 85 or more, and even more preferably 95 or more as an L value measured with a colorimeter.

The inorganic solid acid used in the present invention tends to exhibit an antiviral effect when it has a certain water content. The water content is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 3% by mass or more. In addition, the hygroscopic inorganic solid acid can retain moisture in the inorganic solid acid even when it is mixed with other materials or when the humidity of the atmosphere changes. It is excellent in that the inorganic solid acid itself has the necessary moisture.

Such inorganic solid acids are also commercially available. For example, Novaron series manufactured by Toagosei Co., Ltd. can be used as a preferable inorganic solid acid.

(Manufacturing method of overprint varnish)
The overprint varnish of the present invention can be produced by a conventionally known method using the raw materials described above. In the case of an overprint varnish with a matting effect, for example, resins containing the rosin-modified phenolic resin, vegetable oils or fatty acid esters, or mixtures thereof, and if necessary, petroleum solvents, chelating agents, and other aids. Additives and the like are added to the varnish prepared by heating and dissolving the agents and the like, and the mixture is thoroughly premixed with a stirrer, and then kneaded with a shot mill, roll mill, or the like. After kneading, auxiliary agents such as varnish, petroleum solvent, vegetable oil, other waxes, antioxidants and emulsification modifiers are added and thoroughly stirred and mixed. The inorganic solid acid and wax may be added during premixing or after kneading.

The amount of these raw materials used is adjusted according to the viscosity and fluidity required for the overprint varnish. Moreover, the timing of addition of these raw materials is not fixed, but is appropriately adjusted based on the state of mixing.

(printed matter)
The printed material of the present invention can be obtained by coating the above-described overprint varnish composition on a printed material printed directly on a substrate or by a lithographic offset printing machine using an oxidative polymerization type offset printing ink composition. . The overprint varnish composition may be applied to the entire surface of the printed matter, or may be applied to only a portion of the printed matter. The amount of coating may be appropriately adjusted depending on the purpose of coating the overprint varnish composition. As an example, the thickness of the coating film of the overprint varnish composition after drying is about 0.5 μm to 1.5 μm. adjust.

The coating method may be a so-called in-line method in which a coating apparatus is installed in a lithographic offset printing machine and the overprint varnish is applied subsequently to printing using a printing ink composition, or lithographic offset printing. A so-called off-line method, in which a coater equipped with a gravure or flexographic coating device is used after printing with a machine, may be used.

(Paper substrate)
The substrate is not particularly limited, and conventionally known substrates can be used, but it is particularly suitable for printing on paper substrates such as coated paper, matte coated paper, and woodfree paper. Backing paper, impregnated paper, cardboard, paperboard and the like can also be used.

(Plastic substrate)
Moreover, you may apply to a plastic base material. The plastic substrate may be a substrate used for substrates such as plastic materials, molded articles, film substrates, and packaging materials. Specifically, for example, polyamide resins such as nylon 6, nylon 66, nylon 46, polyethylene terephthalate (hereinafter sometimes referred to as PET), polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polybutylene terephthalate, Polyester resins such as polybutylene naphthalate, polyhydroxycarboxylic acids such as polylactic acid, biodegradable resins such as aliphatic polyester resins such as poly(ethylene succinate) and poly(butylene succinate), polypropylene, polyethylene, etc. Polyolefin resins, polyimide resins, polyarylate resins, or films made of thermoplastic resins such as polyarylate resins or mixtures thereof, and laminates thereof. Among them, films made of polyethylene terephthalate (PET), polyester, polyamide, polyethylene, and polypropylene can be preferably used. These base films may be either unstretched films or stretched films, and the manufacturing method thereof is not limited. Also, the thickness of the base film is not particularly limited, but it is usually in the range of 1 to 500 μm. Further, the substrate film is preferably subjected to corona discharge treatment, and aluminum, silica, alumina, or the like may be deposited thereon. The base material is a laminate (sometimes referred to as a laminated film) having a laminated structure obtained by laminating the paper base material or film base material by a dry lamination method, a solventless lamination method, or an extrusion lamination method. I don't mind.

The paper substrate or plastic substrate may further have a printing ink layer. The printing ink used for the printing ink layer is not particularly limited, and offset lithographic ink, gravure printing ink, flexographic printing ink, inkjet printing ink, etc. can be applied onto the printing layer. In particular, as described above, the method of applying an oxidative polymerization type offset printing ink composition to a printed matter printed by a lithographic offset printing machine is industrially preferable.

(containers, packaging materials)
The single-layer paper substrate or film substrate and the laminate having a laminated structure are functional films, flexible packaging films, shrink films, packaging films for daily necessities, pharmaceutical packaging films, food products, etc., depending on the industry and method of use. Packaging films, cartons, posters, flyers, CD jackets, direct mail, pamphlets, high-quality paper, coated paper, art paper, imitation paper, thin paper, cardboard, etc. used for packages of cosmetics, beverages, pharmaceuticals, toys, equipment, etc. paper, various synthetic papers, etc., but the overprint varnish of the present invention can be used without any particular limitation. These substrates coated with the overprint varnish of the present invention are molded into containers and packaging materials. It is preferably coated on the surface to be the surface layer.

EXAMPLES The contents and effects of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

<Synthesis of rosin-modified phenolic resin>
1000 parts of para-tertial butylphenol, 360 parts of 92% paraformaldehyde, 1000 parts of xylene and 10 parts of 50% sodium hydroxide are charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction device, After raising the temperature to 95° C. and reacting for 6 hours while maintaining the same temperature, 300 parts of water and 13 parts of hydrochloric acid were mixed and neutralized. The temperature was raised to 120° C. and the mixture was stirred for 30 minutes.

970 parts of gum rosin having an acid value of 165 mgKOH/g and 14 parts of maleic anhydride are charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction device, heated to 180° C., and pentaerythritol 107 is added. and 2 parts of zinc oxide were added, the temperature was raised to 250° C., and the reaction was carried out while maintaining the same temperature until the acid value became 20 mgKOH/g or less. After that, the temperature was lowered to 180 ° C., and while maintaining the same temperature, a resol type phenolic resin was added dropwise using a dropping funnel at a dropping rate of 2.5 parts / minute, and the 25 ° C. Gardner viscosity of the 50% toluene solution became F to G. After 30 minutes, the resin was taken out to obtain a rosin-modified phenolic resin.

<Production of rosin-modified phenolic resin varnish>
440 parts of rosin-modified phenolic resin and 140 parts of soybean salad oil were placed in a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction device, and heated and stirred at 180° C. for 1 hour. After that, 410 parts of AF Solvent No. 6 are added, the temperature is lowered to 160° C., 10 parts of ethylacetoacetate aluminum di-n-butyrate are added, and the temperature is maintained for 1 hour to obtain a rosin-modified phenolic resin varnish (resin content: 44% by mass). rice field.

<Synthesis of rosin ester resin>
1,000 parts of gum rosin (acid value: 165 KOH mg/g) and 106 parts of fumaric acid were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas introduction device, and stirred at 220°C for 1 hour under a stream of nitrogen. After heating and stirring for hours to obtain a reaction mixture containing acid-modified gum rosin and unreacted gum rosin and having an acid value of 242 KOH mg/g, 317 parts of linseed oil and 162 parts of pentaerythritol were added and mixed, and 1.5 parts of magnesium oxide was added as a catalyst. When 5 parts were added and stirred and mixed, the temperature in the reaction vessel reached 161°C. Next, the reaction vessel is heated and reacted while raising the temperature to 270°C at a rate of temperature increase of 30°C/hr, and further reacted at 270°C until the acid value becomes 20 KOHmg/g or less to obtain a modified rosin ester. A rosin ester resin containing resin, unreacted linseed oil and pentaerythritol was obtained.

<Production of rosin ester resin varnish>
520 parts of rosin ester resin, 170 parts of linseed oil, and 300 parts of AF Solvent No. 6 were charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction device, and stirred at 200°C. The viscosity was adjusted within the range of 1,000 to 2,000 dPa·s by keeping the mixture warm for 30 minutes. After cooling to 160° C., 10 parts of ethylacetoacetate aluminum di-n-butyrate was added, the temperature was raised to 200° C., and the temperature was maintained for 60 minutes to obtain a rosin ester resin varnish (resin content: 52% by mass).

<Polyethylene wax compound>
A compound obtained by heating and stirring 35 parts of polyethylene wax and 65 parts of soybean salad oil and then cooling to room temperature was used.

<Manganese octylate solution>
A solution prepared by dissolving 50 parts of manganese octylate in 50 parts of soybean salad oil was used.

<Inorganic solid acid>
An inorganic phosphoric acid compound "Novaron IV1000 (manufactured by Toagosei Co., Ltd.)" was used.

<Organic solvent>
AF No. 6 solvent was used.

<Method for producing overprint varnish>
Various overprint varnishes were obtained by mixing the overprint varnishes of Examples 1 to 8 and Comparative Examples 1 to 5 according to the compositions in Tables 1 and 2 using a stirrer. Blanks in the table are not compounded.

(Evaluation item)
(1) Table Evaluation The overprint varnish was printed under the following conditions, and the dried prints were evaluated for antibacterial properties, antiviral properties, yellowing, gloss, and abrasion resistance.

<Condition>
・Printing machine: RI tester ・Printing paper: OK Topcoat Plus ・Filling amount: 0.125cc

(antibacterial)
The bacterial solution is dropped on the printed surface of the overprint varnish, and the number of viable bacteria is measured after 24 hours at 35° C. and 90% humidity. When the number of bacteria inoculated was 1/1000 or less, it was marked with ⊚, when it was 1/100 or less, it was marked with x. Two types of bacteria, Staphylococcus aureus and Escherichia coli, were evaluated.

(antiviral)
A virus solution is dropped on the printed surface of the overprint varnish, and the number of viruses is measured after 24 hours at 25°C. When the number of viruses inoculated was 1/1000 or less, it was marked with ⊚, when it was 1/100 or less, it was marked with x, and in other cases, it was marked with x. Two types of viruses, influenza A virus and feline calicivirus, were evaluated.

(Yellowing of printed matter)
After the overprint varnish printed matter was passed through an ultraviolet irradiation device, yellowing of the printed surface was visually evaluated. When yellowing was the same as that of overprint varnish to which no antibacterial agent or antiviral agent was added, it was evaluated as ⊚, when yellowing was slightly observed, it was evaluated as ◯, and when yellowing was observed, it was evaluated as ×.

(gloss)
The gloss of the printed surface of the overprint varnish was visually evaluated. When the gloss was the same as that of the overprint varnish to which no antibacterial agent or antiviral agent was added, it was evaluated as ⊚;

(Friction resistance test)
Using a Gakushin type friction tester, rub the overprint varnish printed material 10 times with a load of 500 g, and if the abrasion is the same as that of the overprint varnish without the addition of antibacterial agents and antiviral agents, ◎ indicates slight abrasion. When there was much wear, it was marked with ◯, and when there was much wear, it was marked with x.

(Printability test)
<Printing conditions>
・ Printing machine: LITHRONE G40 (manufactured by Komori Corporation)
・Paper: OK Top Coat + (manufactured by Oji Paper Co., Ltd.)
Dampening water: Presarto-SD100 2.5% tap water diluted solution (manufactured by DIC Graphics Co., Ltd.)
・Printing speed: 10,000 sheets/hour ・Plate: SONORA (manufactured by Kodak LLC)

The printability was confirmed by printing 5,000 copies of each overprint varnish on the above printer. When the printability was comparable to that of an overprint varnish containing no antibacterial agent or antiviral agent, it was evaluated as ⊚;

Tables 1 and 2 show the results. In addition, the blank is not compounded.

Claims (7)

An overprint varnish containing a varnish containing a rosin-modified phenolic resin, a dryer, and wax, wherein at least one inorganic solid acid selected from the group consisting of an inorganic phosphoric acid compound, an inorganic silicic acid compound and an inorganic oxide is added. An overprint varnish characterized by containing 0.5 to 15% by mass. 2. The overprint varnish according to claim 1, wherein the inorganic solid acid is an inorganic phosphoric acid compound and contains 0.5 to 15% by mass. 3. The overprint according to claim 1, wherein the varnish contains a rosin-modified phenolic resin and a rosin-ester resin, and the mass ratio of the rosin-modified phenolic resin:rosin-ester resin is 7:3 to 3:7. varnish. A printed matter comprising a substrate and a printed coating film of the overprint varnish according to any one of claims 1 to 3 disposed on the substrate. A paper substrate or a plastic substrate obtained by applying the overprint varnish according to any one of claims 1 to 3 to a paper substrate and a film. 6. The paper or plastic substrate according to claim 5, wherein said paper or plastic substrate further comprises a printing ink layer. A container or packaging material using the paper base material or plastic base material according to claim 5 or 6.