JP4599476B2 - Paper with antibacterial function - Google Patents

Description

  The present invention relates to a paper paint, a paper product, a paper packaging container, and a method for manufacturing a paper product.

  There are various microorganisms such as bacteria and mold in our living space. These microorganisms often cause food to spoil and generate bad odors, and also cause adverse effects such as food poisoning on the human body.

  By the way, with the development of transportation means and commodity distribution networks, most commodities ranging from industrial products to daily goods are transported in a form protected by packaging materials, and this situation is no exception in the food field.

  Paper packaging materials are frequently used in packaging and packing of foods such as high-class Japanese sweets and cakes that are mainly taken out and fruits. Since these foods require freshness, special attention must be paid to hygiene management during transportation. For these reasons, there is an increasing demand for paper packaging materials having excellent antibacterial properties.

  As antibacterial agents for imparting antibacterial properties to paper, conventionally, quaternary ammonium salts such as benzalkonium chloride (see Patent Document 1), phenol, isopropylmethylphenol, chlorhexidine derivatives (see Patent Document 2), and the like have been disclosed. ing.

  However, although these antibacterial agents can impart excellent antibacterial properties to paper, the safety to the user's human body may be insufficient. Therefore, a technique for impregnating paper with an antibacterial liquid in which a glass antibacterial agent containing monovalent silver ions is dispersed has been developed (see Patent Document 3). According to this technique, since monovalent silver ions having a small adverse effect on the human body are used, safety can be improved and antibacterial properties can be imparted.

  On the other hand, as a method for supplying an antibacterial agent to paper, a method of spraying an antibacterial agent on paper in a conventional manner is generally performed. However, since a significant part of the expensive antibacterial agent is scattered and lost to the surrounding environment, it is not economical, and if the application amount is reduced to improve economy, the amount of antibacterial agent is insufficient and sufficient antibacterial Sex cannot be obtained. Then, the method of making paper after adding an antibacterial agent to a paper raw material is proposed (refer patent document 4). According to this technique, since the whole antibacterial agent to be used is contained in the paper, the antibacterial property can be improved economically.

JP 2006-149989 A JP 2000-191511 A JP 2002-69897 A JP-A-2005-232636

  However, in the technique disclosed in Patent Document 3, the resin is cured in a short time by the catalytic action of silver ions. For this reason, since the lifetime of an antibacterial liquid is very short and it is necessary to manufacture an antibacterial liquid frequently, manufacturing cost will become great.

  Moreover, in the technique shown by patent document 4, when the printing process etc. are further performed on the surface, the formed printing layer coat | covers the surface of a printing part, and inhibits an antimicrobial effect. Thereby, sufficient antibacterial properties may not be obtained.

  The present invention has been made in view of the above circumstances, and is a safe and inexpensive paper coating that can sufficiently impart antibacterial properties to paper, a safe and inexpensive paper product that has sufficient antibacterial properties, and paper packaging. It is an object of the present invention to provide a container and a production method capable of producing a safe paper product having sufficient antibacterial properties at a low cost.

  The present inventors have found that antibacterial properties can be sufficiently imparted to paper by using silver zeolite in combination with other components in a predetermined combination, and the present invention has been completed. More specifically, the present invention provides the following.

  (1) A paper paint applied to the surface of paper, which contains silver zeolite, a water-soluble varnish, and a metal chelating agent.

  According to the invention of (1), since silver zeolite recognized as a safe antibacterial agent is contained, antibacterial properties can be safely imparted to paper. For example, “Zeomic” (manufactured by Sinanen Zeomic), a type of silver zeolite, is approved by the US Food and Drug Administration (FDA) as a food contact substance (Food Contact Substance Notification FCN000047) and can be applied to packaging resins for all foods. There is a track record.

  In addition, since the water-soluble varnish itself has a viscosity, the paint is given a viscosity and, for example, is easily wetted with a printing roll of a printing press. Thereby, since a coating material is uniformly apply | coated to the surface of paper, antibacterial property can fully be provided to paper.

  And since viscosity is provided even if it does not contain a thickener further, manufacturing cost can be reduced. However, a thickener may be further contained in order to obtain a desired viscosity, and paper paints containing a thickener are not excluded.

  The paper surface to which the paper paint is applied is coated with a layer of silver zeolite and water-soluble varnish to impart water resistance. For this reason, since it is not necessary to perform special ground processing, the manufacturing cost of paper products can be reduced and the manufacturing line can be simplified.

However, in general, there is a problem that the compatibility between the silver zeolite and the water-soluble varnish is insufficient.
Therefore, according to the invention of (1), since the metal chelating agent is contained, the compatibility between the silver zeolite and the water-soluble varnish is improved, and the dispersibility of the silver zeolite is improved. Thereby, since precipitation of silver zeolite is suppressed, the life of the antibacterial liquid is prolonged. Therefore, it is not necessary to remanufacture the antibacterial liquid frequently, and the manufacturing cost can be reduced.

  In fact, when no metal chelating agent is added, silver zeolite precipitates and begins to solidify overnight after preparation, but when a metal chelating agent is added, it can be simply circulated internally, for example, in a paint tank of a printing press. In addition, almost no precipitation or solidification of silver zeolite is observed.

  The “paper paint” as used herein can be applied to any application where antibacterial properties are required, particularly products that are expected to be in direct or indirect contact with the human body. Specifically, wrapping paper represented by cardboard and cardboard (especially food), water retaining materials used in humidifiers and humidity controllers, hygiene-related products (for example, wet tissues, hand towels), and building-related wall materials , Flooring materials, anti-condensation materials, agricultural water-retaining bodies, air conditioning or water treatment filters, water antibacterial treatment materials, and the like.

  The “coating” as used herein is not particularly limited as long as the antibacterial effect is imparted to the paper surface. For example, it may be impregnation, transfer by a printing roll, or spraying.

  (2) The paper coating material according to (1), wherein the metal chelating agent has a propylene glycol group in the molecule.

According to the invention of (2), since the metal chelating agent having a propylene glycol group in the molecule is employed, a complex is formed by the silver ion in the silver zeolite and the propylene glycol group in the molecule. Thereby, in the state disperse | distributed to the liquid, the resin hardening action which silver ion has is weakened.
Moreover, the propylene glycol group acts as a hydrophilic group, and the water dispersibility of the silver zeolite itself is improved.
Therefore, the lifetime of the antibacterial liquid is further prolonged, so that the manufacturing cost can be further reduced.

  (3) The paper coating material according to (1) or (2), wherein the metal chelating agent has a triple bond and an ethylene oxide group in the molecule.

According to the invention of (3), since a metal chelating agent having a triple bond and an ethylene oxide group in the molecule is employed, a complex is formed by the silver ion in the silver zeolite and the triple bond and the ethylene oxide group in the molecule. Is done. Thereby, in the state disperse | distributed to the liquid, the resin hardening action which silver ion has is weakened.
In addition, triple bonds and ethylene oxide groups act as hydrophilic groups, and the water dispersibility of the silver zeolite itself is improved.
Therefore, the lifetime of the antibacterial liquid is further prolonged, so that the manufacturing cost can be further reduced.

  (4) The paper paint according to any one of (1) to (3), wherein the water-soluble varnish is acrylic.

  According to the invention of (4), since the acrylic type is adopted as the water-soluble varnish, the polymerization rate at the time of curing is increased as compared with a thermosetting resin having an epoxy group or the like in the molecule. Thereby, since the curing time is shortened, not only the production efficiency can be improved, but also the warping of the paper can be suppressed.

  (5) A paper product in which the paper paint according to any one of (1) to (4) is applied to the surface of paper.

  According to the invention of (5), since the paper paint according to any one of (1) to (4) is applied on the surface, a safe and inexpensive paper product having sufficient antibacterial properties can be provided. This paper product can be applied to various fields where antibacterial properties are required.

  (6) A paper packaging container formed of the paper product according to (5).

  (7) The paper packaging container according to (6), which is used for food packaging.

  According to the invention of (7), since the paper product described in (6) is used, a safe and inexpensive paper packaging container having sufficient antibacterial properties can be provided. This paper packaging container can be used for packaging various products that require antibacterial properties. In particular, it can provide a highly sanitary environment required for food.

  (8) A method for manufacturing a paper product, comprising: an application procedure for applying the paper paint according to any one of (1) to (4) to a paper surface; and a curing procedure for curing the paper paint. Method.

  According to the invention of (8), since the paper paint described in any one of (1) to (4) is adopted as the paper paint, a safe and inexpensive paint is uniformly applied to the paper surface in the application procedure. The Therefore, a safe and inexpensive paper product to which antibacterial properties are sufficiently imparted can be manufactured through a curing procedure.

  The paper coating material may be cured by various conventionally known methods such as hot air drying and active energy ray irradiation. Of these, irradiation with active energy rays (for example, far infrared rays) is preferable in that damage to paper products due to heat can be suppressed.

  (9) The manufacturing method according to (8), wherein the application procedure is performed after a printing procedure for performing a printing process on a paper surface.

When the printing process is performed after the paper paint is applied, the formed printed layer covers the surface of the printed portion and inhibits the antibacterial effect. Thereby, there is a concern that sufficient antibacterial properties cannot be obtained.
Therefore, according to the invention of (9), since the application procedure is provided after the printing procedure, the paper paint is applied to the entire surface including the print portion. Therefore, antibacterial properties can be further improved.

  The printing procedure prints characters, patterns, and colors. Examples of the printed content include information on the contents to be packaged, and specifically include a picture of a packaged food, a product name, a production place, a distributor, and the like.

  (10) The production according to (8) or (9), wherein the application procedure is a procedure in which the paper surface is brought into contact with a printing roll having a flat surface and the paper paint is adhered to the surface. Method.

  According to the invention of (10), the paper paint adhered to the roll surface is transferred to the paper surface in contact with the printing roll. Thus, since the paper coating material is used without waste, it is economical.

  Further, since the paper paint is attached to the flat surface, the paper paint is transferred to the entire surface in contact with the roll. Therefore, antibacterial properties can be further improved.

  Here, the “flat surface” refers to a surface on which printing unevenness is not formed. The “contact” method is not particularly limited, and for example, it may be a method of passing paper while being pressed against a printing roll.

  (11) The said hardening procedure is a manufacturing method in any one of (8) to (10) performed in 70-120 degreeC hot air.

  According to the invention of (11), since hot air drying that is most widely used as a curing method is adopted, there is no need to newly establish or change a production line, which is economical.

  However, if the hot air temperature is too low, curing will be insufficient, while if it is too high, the paper may be damaged. Then, according to invention of (11), since it hardens | cures in a 70-120 degreeC hot air, the damage given to paper can be suppressed and it can fully harden | cure.

  (12) The manufacturing method according to (11), wherein the curing procedure is performed for 5 to 60 seconds.

  If the treatment time in hot air is too short, curing will be insufficient, while if it is too long, the paper may be damaged. Therefore, according to the invention of (12), since the treatment time in hot air is set to 5 to 60 seconds, damage to the paper can be suppressed and the paper can be sufficiently cured.

  According to the present invention, a safe and inexpensive paper coating that can sufficiently impart antibacterial properties to paper, a safe and inexpensive paper product that has sufficient antibacterial properties, a paper packaging container, and a sufficient antibacterial property. In addition, it is possible to provide a manufacturing method that can manufacture a safe paper product at a low cost.

<Example 1>
First, 5 parts by mass of silver zeolite was added to 10 parts by mass of distilled water, and the mixture was stirred and mixed. Next, 0.1 part by mass of “Surfinol 485 (trade name)” (manufactured by Nissin Chemical Industry Co., Ltd.), which is a metal chelating agent having a triple bond and an ethylene oxide group in the molecule, was added and stirred at room temperature for 15 minutes. . Thereafter, 60 parts by mass of “Aqua Pack Varnish F-68 (trade name)” (manufactured by T & K TOKA), which is an acrylic water-soluble varnish, was added with stirring to obtain a paper paint.

Next, a printing roll with a flat printing surface of a gravure printing machine was used, and a paper paint was applied to the surface at a rate of 15 g / m ² (application procedure). By passing the paper surface through this roll, the paper paint was transferred to the paper surface, and then air-dried at 120 ° C. for 3 seconds and then for 7 seconds (curing procedure) to obtain a paper product.

<Example 2>
Instead of “Surfinol 485 (trade name)” (manufactured by Nissin Chemical Industry Co., Ltd.), “Surfinol 104 (trade name)” (manufactured by Nissin Chemical Industry Co., Ltd.), which is a metal chelating agent having a propylene glycol group in the molecule. ) Was used in the same procedure as in Example 1 except that

[Evaluation]
The paper products obtained in Examples 1 and 2 were evaluated for antibacterial properties based on “JIS Z2801”. Specifically, first, each of the paper products of Examples 1 and 2 and untreated paper was sterilized by moist heat (121 ° C., 15 minutes), and then a predetermined amount of yellow grapes was placed on one side of each paper (4 cm × 4 cm). Inoculated with cocci or E. coli. Subsequently, after maintaining at 35 ° C. for 24 hours, the number of bacteria on each paper was measured. The results are shown in Table 1.

  As shown in Table 1, in the untreated paper, the number of bacteria after holding increased compared to the initial number of bacteria, but in the paper products obtained in Examples 1 and 2, after holding compared to the initial number of bacteria. The number of bacteria was significantly reduced. Specifically, in the paper products of Examples 1 and 2, Staphylococcus aureus disappeared and the number of E. coli was drastically reduced. Thus, it was confirmed that the paper products of the examples of the present invention have particularly excellent antibacterial properties.

Claims (11)

A paper paint applied to the surface of paper,
A paper paint containing silver zeolite, a water-soluble varnish, and a metal chelating agent having a propylene glycol group in the molecule . A paper paint applied to the surface of paper,
A paper paint containing silver zeolite, a water-soluble varnish, and a metal chelating agent having a triple bond and an ethylene oxide group in the molecule . The paper paint according to claim 1 or 2 , wherein the water-soluble varnish is acrylic. A paper product in which the paper paint according to any one of claims 1 to 3 is applied to the surface of paper. A paper packaging container formed of the paper product according to claim 4 . The paper packaging container according to claim 5, which is used for packaging food. A method of manufacturing a paper product,
The paper coating according to any one of claims 1 3 and Application Procedure to be applied to the paper surface,
A curing procedure for curing the paper paint. The manufacturing method according to claim 7 , wherein the coating procedure is performed after a printing procedure for performing a printing process on a paper surface. The manufacturing method according to claim 7 or 8 , wherein the application procedure is a procedure in which the paper surface is brought into contact with a printing roll having a flat surface and the paper paint is adhered to the surface. The said hardening procedure is a manufacturing method in any one of Claim 7 to 9 performed in a 70-120 degreeC hot air. The manufacturing method according to claim 10 , wherein the curing procedure is performed for 5 to 60 seconds.