Antibacterial-antiviral varnish composition

Abstract

To provide an aqueous antibacterial-antiviral varnish composition with antibacterial-antiviral properties, exhibiting excellent storage stability.SOLUTION: An antibacterial-antiviral varnish composition may contain an antibacterial-antiviral agent, an acrylic resin, and an aqueous solvent, where the antibacterial-antiviral agent may contain all of silver oxide, calcium phosphate, zinc phosphate and aluminium phosphate, or may contain silver oxide and zinc phosphate calcium. The antibacterial-antiviral varnish composition of such a composition exhibits superior storage stability.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an antibacterial and antiviral varnish composition. [Background technology]

[0002] In recent years, interest in infection control measures, including hand disinfection and wearing masks, has increased in response to the global spread of infectious diseases caused by viruses such as new strains of influenza, SARS (Severe Acute Respiratory Syndrome), and COVID-19. Against this background, active efforts are being made to give antibacterial and antiviral properties to objects that people directly touch, such as the use of antibacterial and antiviral materials for train straps, to improve the sense of security for users.

[0003] One such item that people touch directly is a printed matter printed on a paper substrate. Examples of such printed matter include commercial printed matter such as booklets, catalogs, flyers, and calendars, and it is known that bacteria such as E. coli and viruses adhere to the surface of printed matter when users touch them directly. For example, in the case of the new coronavirus, it is known that the virus remains active for several days on the surface it is attached to, so it is possible that printed matter with these bacteria or viruses attached to it could be the cause of new infections.

[0004] In light of this, it has been proposed to impart antibacterial and antiviral properties to printed matter by applying an overprint varnish or coating agent containing an antibacterial or antiviral agent to the surface of offset printed matter (see, for example, Patent Document 1). The invention described in Patent Document 1 is said to impart antibacterial properties by adding a nanosilver dispersion to an oil-based overprint varnish. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2010-194723 A Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, when applying varnish to a printed matter, in addition to the above-mentioned overprint varnish, an aqueous varnish composition containing a resin emulsion may also be used. Such a varnish composition provides a printed matter with a high gloss and durable film (hereinafter also referred to as a varnish film), and is therefore useful for obtaining printed matter that requires properties such as cosmetic appearance and abrasion resistance. As described above, this aqueous varnish composition contains a resin emulsion, and this emulsion forms a film as the varnish dries, forming the above-mentioned film on the surface of the printed matter.

[0007] However, in such aqueous varnish compositions, problems may arise such as the resin emulsion being altered by the added compounds, resulting in reduced storage stability, etc. Therefore, even if it is possible to impart antibacterial and antiviral properties to an aqueous varnish composition by adding a known antibacterial and antiviral agent, problems may arise in terms of storage stability.

[0008] The present invention has been made in consideration of the above circumstances, and has an object to provide an aqueous antibacterial and antiviral varnish composition that has antibacterial and antiviral properties and good storage stability. [Means for solving the problem]

[0009] As a result of extensive research into solving the above problems, the present inventors discovered that the storage stability of an aqueous varnish composition is not impaired by using all of silver oxide, calcium phosphate, zinc phosphate and aluminum phosphate, or silver oxide and zinc calcium phosphate, as the antibacterial and antiviral agents in the composition, and thus completed the present invention. Specifically, the present invention provides the following:

[0010] (1) The present invention relates to a composition for producing an antibacterial and / or antiviral agent, an acrylic resin, and an aqueous solvent, The antibacterial and antiviral agent is an antibacterial and antiviral varnish composition characterized in that it contains all of silver oxide, calcium phosphate, zinc phosphate and aluminum phosphate, or silver oxide and zinc calcium phosphate.

[0011] (2) The present invention also relates to an antibacterial and antiviral varnish composition according to item (1), characterized in that the antibacterial and antiviral agent contains silver oxide and calcium zinc phosphate.

[0012] (3) The present invention also relates to an antibacterial and antiviral varnish composition according to item (1) or (2), characterized in that the acrylic resin contains acrylic resin A having a glass transition temperature of less than 50°C and acrylic resin B having a glass transition temperature of 50°C or higher.

[0013] (4) The present invention also relates to an antibacterial and antiviral varnish composition according to any one of items (1) to (3), in which the content of the antibacterial and antiviral agent as a solid content is 0.5% by mass to 10% by mass based on the total mass of the composition.

[0014] (5) The present invention also relates to an antibacterial and antiviral varnish composition according to any one of (1) to (4), further comprising a polyolefin wax.

[0015] (6) The present invention also relates to an antibacterial and antiviral varnish composition according to item (3), characterized in that the acrylic resin B contains an acrylic resin B1 having a glass transition temperature of 50°C or more and less than 100°C, and an acrylic resin B2 having a glass transition temperature of 100°C or more.

[0016] (7) The present invention also relates to an antibacterial and antiviral varnish composition according to item (5), wherein the polyolefin wax is a polyethylene wax.

[0017] (8) The present invention also relates to an antibacterial and antiviral varnish composition according to item (7), characterized in that the polyethylene wax has a particle size of 0.01 μm to 1 μm.

[0018] (9) The present invention also relates to an antibacterial and antiviral varnish composition according to item (8), characterized in that the composition contains 1% by mass to 3% by mass of polyethylene wax having a particle diameter of 0.01 μm to 1 μm, as a solid content. Effect of the Invention

[0019] According to the present invention, there is provided an aqueous antibacterial and antiviral varnish composition that has antibacterial and antiviral properties and good storage stability. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] An embodiment of the antibacterial and antiviral varnish composition of the present invention will be described below. Note that the present invention is not limited to the following embodiment, and can be practiced with appropriate modifications within the scope of the present invention.

[0021] The antibacterial and antiviral varnish composition of the present invention (hereinafter appropriately abbreviated as "the composition of the present invention" etc.) is used to coat the surface of a printed material after printing. A preferred example of such a printed material is a printed material obtained by offset printing, but is not particularly limited. An example of coating the printed material with the composition of the present invention is applying it to the printed material after printing using a known coater. Since the composition of the present invention contains an antibacterial and antiviral agent, the varnish film formed thereby has antibacterial and antiviral properties. Therefore, a printed material on which a varnish film is formed by the composition of the present invention has antibacterial and antiviral properties.

[0022] The antibacterial and antiviral varnish composition of the present invention contains an antibacterial and antiviral agent, an acrylic resin, and an aqueous solvent, and preferably further contains a polyolefin wax. These will be described below.

[0023] [Antibacterial and antiviral agents] The antibacterial and antiviral agent used in the composition of the present invention is characterized by containing all of silver oxide, calcium phosphate, zinc phosphate and aluminum phosphate, or silver oxide and zinc calcium phosphate. That is, the antibacterial and antiviral agent used in the composition of the present invention contains all of the four compounds consisting of silver oxide, calcium phosphate, zinc phosphate and aluminum phosphate, or contains all of the two compounds consisting of silver oxide and zinc calcium phosphate. In the present invention, the term "antibacterial and antiviral" is used to mean "antibacterial and / or antiviral".

[0024] The difference between the former and the latter is that in addition to silver oxide, (1) calcium phosphate, zinc phosphate, and aluminum phosphate are contained, or (2) zinc calcium phosphate is contained. Whether in the form (1) or the form (2), the antibacterial and antiviral effects specified in the present invention can be obtained, the storage stability of the aqueous varnish composition is not impaired, and the light resistance of the formed varnish film is not impaired.

[0025] In the case of the form (1), the mixture ratio of silver oxide, calcium phosphate, zinc phosphate, and aluminum phosphate is optional, and they may be contained in any ratio. In the case of the form (2), the mixture ratio of silver oxide and zinc calcium phosphate is optional, and they may be contained in any ratio. Such antibacterial and antiviral agents are commercially available, and examples of such agents include products such as MP-102SVP05 and Bactekiller BM-102SVP(DH) manufactured by Fuji Chemical Co., Ltd.

[0026] The content of the antibacterial and antiviral agent in the composition of the present invention is preferably 0.5% by mass to 10% by mass, more preferably 0.5% by mass to 7% by mass, and even more preferably 0.5% by mass to 5% by mass, relative to the total composition as a solid content.

[0027] [Acrylic resin] The acrylic resin is used in the form of an emulsion in an aqueous solvent, or in the form of a varnish in which the acrylic resin is neutralized and solubilized in an aqueous solvent. Various types of such emulsions are commercially available. The acrylic resin in the present invention is a polymerized material using at least one of acrylic acid, acrylic acid esters, methacrylic acid, and methacrylic acid esters as a monomer, and may be a homopolymer, a copolymer containing a plurality of these monomers, or a copolymer with other monomers such as styrene. In this way, even if it is a copolymer with a monomer different from acrylic acid, acrylic acid esters, methacrylic acid, and methacrylic acid esters, the one containing at least one of acrylic acid, acrylic acid esters, methacrylic acid, and methacrylic acid esters as a monomer component is called an acrylic resin in the present invention.

[0028] The acrylic resin used in the present invention is preferably a combination of an acrylic resin A having a glass transition temperature of less than 50° C. and an acrylic resin B having a glass transition temperature of at least 50° C. The use of an acrylic resin with a low glass transition temperature is preferable because it improves the leveling of the formed varnish film and increases the gloss, while the use of an acrylic resin with a high glass transition temperature is preferable because it can suppress blocking of the printed matter on which the varnish film is formed and improves abrasion resistance.

[0029] The acrylic resin B is preferably a combination of an acrylic resin B1 having a glass transition temperature of 50° C. or more and less than 100° C., and an acrylic resin B2 having a glass transition temperature of 100° C. or more.

[0030] The content of the acrylic resin in the composition of the present invention, as a solid content, is preferably 10% by mass to 40% by mass, more preferably 10% by mass to 35% by mass, and even more preferably 13% by mass to 35% by mass, relative to the entire composition.

[0031] Furthermore, when the acrylic resins A and B are used as described above, the solid content ratio of acrylic resin A / acrylic resin B is preferably from 1 to 1.5, and more preferably from 1 to 1.3.

[0032] When the acrylic resins B1 and B2 are used as described above, the solid content ratio of the acrylic resin B1 / the acrylic resin B2 is preferably from 1 to 2, more preferably from 1.2 to 1.8, and even more preferably from 1.3 to 1.7.

[0033] In the present invention, the glass transition temperature is a theoretical glass transition temperature calculated by the following Wood's formula. Wood's formula: 1 / Tg=W1 / Tg1+W2 / Tg2+W3 / Tg3+…+W x / Tg x (In the above formula, Tg1 to Tg x are the glass transition temperatures of the homopolymers of the monomers 1, 2, 3, . . . , x that make up the copolymer, and W1~W x are the mass fractions of monomers 1, 2, 3, . . . , and x, respectively, and Tg is the theoretical glass transition temperature. Note that the glass transition temperature in Wood's equation is an absolute temperature.)

[0034] [Water-based solvent] Next, the water-based solvent will be described. The composition of the present invention is one in which all liquid components evaporate and dry to solidify. The solvent used is a water-based solvent. The water-based solvent is derived from a solvent contained in an acrylic resin emulsion or a solvent added to adjust the viscosity or concentration when preparing the composition.

[0035] The aqueous solvent may be water alone or a mixture of water and one or more water-soluble organic solvents. Examples of such water-soluble organic solvents include alcohols such as methanol, ethanol, n-propanol, n-butanol, n-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonyl alcohol, n-decanol, or isomers thereof, cyclopentanol, and cyclohexanol; polyols such as ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 1,2-pentanediol, 1,5-pentanediol, neopentyl glycol, 1,2-hexanediol, 1,6-hexanediol, 1,2-cyclohexanediol, heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, glycerin, pentaerythritol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, polypropylene glycol, and thiodiglycol; and propylene carbonate.

[0036] [Polyolefin wax] The composition of the present invention preferably contains a polyolefin wax. The polyolefin wax is added mainly to improve the abrasion resistance of the varnish film. As the polyolefin wax, a polyethylene wax can be preferably used.

[0037] The content of the polyolefin wax in the composition of the present invention is preferably 1% by mass to 5% by mass, more preferably 1% by mass to 4% by mass, and even more preferably 1% by mass to 3% by mass, in terms of solid content, relative to the entire composition.

[0038] When a polyethylene wax is used as the polyolefin wax, it is preferable to use one having a particle size of 0.01 μm to 1 μm, and more preferably to use one having a particle size of 0.05 μm to 0.5 μm. In particular, the polyethylene wax having such a particle size range is preferably contained in the composition of the present invention in an amount of 1% by mass to 3% by mass, and more preferably 1.5% by mass to 2% by mass, as a solid content. By containing the polyethylene wax having the above particle size range in this amount, it is preferable because the abrasion resistance of the varnish film can be improved.

[0039] [Other ingredients] If necessary, various additives such as surfactants, plasticizers, polymerization inhibitors, surface conditioners, ultraviolet inhibitors, light stabilizers, antioxidants, etc. may be added to the composition of the present invention within the range that does not impair the effects of the present invention. In addition, the composition of the present invention may contain known inorganic or organic coloring materials.

[0040] [Method of producing the composition of the present invention] The composition of the present invention can be obtained by stirring and mixing the above-mentioned materials, for example, using a stirring blade and a stirrer, etc. The content of the aqueous solvent in the composition of the present invention is the amount obtained by subtracting the total amount of each solid content and other additives used as necessary from the total amount of the composition.

[0041] As described above, the acrylic resin may be used in the form of a varnish obtained by neutralizing and solubilizing the acrylic resin in an aqueous solvent. In this case, the varnish containing the solubilized acrylic resin will be alkaline, and in the composition of the present invention, the pH of the entire composition is preferably 7 to 11, more preferably 7 to 9. By keeping the pH in this range, it is possible to prevent the silver oxide contained in the antibacterial and antiviral agent from becoming discolored due to high pH conditions. EXAMPLES

[0042] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" means "% by mass."

[0043] [Acrylic resin A] An aqueous solution of an ammonia neutralized alkali-soluble resin consisting of 32% by mass of acrylic acid, 14% by mass of styrene, and 54% by mass of α-methylstyrene was prepared as a polymeric emulsion. 39 parts by mass of 2-ethylhexyl acrylate and 31 parts by mass of styrene were added to 30 parts by mass of the resin solid content of this polymeric emulsion, and emulsion polymerization was carried out by a conventional method to obtain an emulsion of acrylic resin A with an acid value of 75 mgKOH / g, a glass transition temperature of 0°C, and a solid content of 48% by mass.

[0044] [Acrylic resin B1] Joncryl PDX-7667 (product name: styrene-acrylic copolymer, acid value of resin solids: 182 mgKOH / g, glass transition temperature: 75° C., solids content: 45% by mass), manufactured by BASF Japan, was used as the emulsion of acrylic resin B1.

[0045] [Acrylic resin B2] 30 parts by mass of JONCRYL 690 (product name: BASF Japan Ltd., copolymer of styrene-acrylic resin, acid value: 240 mgKOH / g, glass transition temperature: 114°C, solid content: 100% by mass) and 60 parts by mass of water were mixed and heated to 90°C with stirring. The acrylic resin was neutralized and dissolved with 25% ammonia water to a pH of 8.5, and an amount of water to adjust the pH was added to obtain a varnish of acrylic resin B2 (solid content: 30% by mass).

[0046] [Preparation of antibacterial and antiviral varnish composition] The components were mixed in the blending ratios shown in Table 1 to prepare varnish compositions of Examples 1 to 5 and Comparative Examples 1 to 4. In Tables 1 and 2, "antibacterial and antiviral agent 1" is manufactured by Fuji Chemical Co., Ltd. under the trade name Bactekilar BM-102SVP(DH) (antibacterial and antiviral agent containing silver oxide and zinc calcium phosphate, solid content 100% by mass), "antibacterial and antiviral agent 2" is manufactured by Fuji Chemical Co., Ltd. under the trade name MP-102SVP05 (antibacterial and antiviral agent containing silver oxide and zinc calcium phosphate, solid content 25% by mass), and "antibacterial and antiviral agent 3" is manufactured by Ishizuka Chemical Industry Co., Ltd. under the trade name ZAF-HS (antibacterial and antiviral agent not containing zinc, which is a particle in which silver is supported on soluble glass and silica particles containing a silver component, solid content 100% by mass). "Antibacterial and antiviral agent 4" is manufactured by Koa Glass Co., Ltd. under the trade name PG711 (antibacterial and antiviral agent made of glass carrying silver ions and containing no aluminum, average particle size 3 μm, solid content 100% by mass), "antibacterial and antiviral agent 5" is manufactured by Koa Glass Co., Ltd. under the trade name PG721F (antibacterial and antiviral agent made of silver glass and containing no aluminum, volume average particle size 1 μm, silver concentration 2.0%, solid content 100% by mass), and "antibacterial and antiviral agent 6" is manufactured by Yamato Chemical Industry Co., Ltd. under the trade name Amolden D-CL50 (antibacterial and antiviral agent made of a cationic polymer and containing no zinc, calcium, or silver, solid content 50% by mass). Of these antibacterial and antiviral agents, "antibacterial and antiviral agent 1" and "antibacterial and antiviral agent 2" are the antibacterial and antiviral agents specified in the present invention.

[0047] In addition, in Table 1, "Wax 1" is a product manufactured by BYK under the trade name of AQUACER 1082 (polyethylene wax, particle size 0.1 μm, solid content 40% by mass), "Wax 2" is a product manufactured by Mitsui Chemicals, Inc. under the trade name of Chemipearl W-400 (polyethylene wax, particle size 4 μm, solid content 40% by mass), and "Additive" is a product manufactured by Nissin Chemical Industry Co., Ltd. under the trade name of Surfynol 104DEG (acetylene diol surfactant).

[0048] [Storage stability evaluation of varnish composition 1 (coloration suppression)] Each of the varnish compositions of the Examples and Comparative Examples was left to stand at 60° C. for 5 days, and then the presence or absence of coloring of the varnish composition was visually confirmed. The evaluation criteria were as follows, and the results are shown in the “Storage stability (coloring)” column in Table 1. ○: No coloring was observed △: Slight yellowing was observed, but not enough to cause any practical problems. ×: Colored brown and unusable

[0049] [Evaluation of storage stability of varnish composition 2 (precipitating inhibition)] Each of the varnish compositions of the Examples and Comparative Examples was left to stand at 60° C. for 5 days, and then the presence or absence of precipitation in the varnish composition was visually confirmed. The evaluation criteria were as follows, and the results are shown in the “Storage stability (precipitation)” column in Table 1. ○: No precipitation was observed ×: Precipitation was observed

[0050] [Evaluation of storage stability of varnish composition 3 (fluidity)] Each of the varnish compositions of the Examples and Comparative Examples was allowed to stand at 60° C. for 5 days, and then the change in fluidity of the varnish composition was confirmed. The evaluation criteria were as follows, and the results are shown in the “Storage stability (fluidity)” column in Table 1. ○: No increase in viscosity was observed △: Viscosity increased, but recovered by shaking, no practical problem ×: The varnish composition solidified and could not be restored even by shaking.

[0051] [Table 1]

[0052] As shown in Table 1, it can be seen that the composition of the present invention exhibits practical storage stability even though it contains an antibacterial and antiviral agent.

Claims

1. Contains an antibacterial / antiviral agent, an acrylic resin, and a water-based solvent, An antibacterial and antiviral varnish composition, characterized in that the antibacterial and antiviral agent contains all of silver oxide, calcium phosphate, zinc phosphate and aluminum phosphate, or silver oxide and zinc calcium phosphate.

2. 2. The antibacterial and antiviral varnish composition according to claim 1, wherein the antibacterial and antiviral agent contains silver oxide and calcium zinc phosphate.

3. 3. The antibacterial and antiviral varnish composition according to claim 1, wherein the acrylic resin contains an acrylic resin A having a glass transition temperature of less than 50°C and an acrylic resin B having a glass transition temperature of 50°C or higher.

4. 3. The antibacterial and antiviral varnish composition according to claim 1, wherein the content of the antibacterial and antiviral agent as solids is 0.5% by mass to 10% by mass based on the total mass of the composition.

5. 3. The antibacterial and antiviral varnish composition according to claim 1 or 2, further comprising a polyolefin wax.

6. 4. The antibacterial and antiviral varnish composition according to claim 3, characterized in that the acrylic resin B contains an acrylic resin B1 having a glass transition temperature of 50°C or higher and lower than 100°C, and an acrylic resin B2 having a glass transition temperature of 100°C or higher.

7. 6. The antibacterial and antiviral varnish composition according to claim 5, wherein the polyolefin wax is a polyethylene wax.

8. 8. The antibacterial and antiviral varnish composition according to claim 7, characterized in that the polyethylene wax has a particle size of 0.01 μm to 1 μm.

9. 9. The antibacterial and antiviral varnish composition according to claim 8, characterized in that the composition contains 1% by mass to 3% by mass of polyethylene wax having a particle size of 0.01 μm to 1 μm, as a solid content.

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