JPH08165364A - Production of antibacterial decorative thermosetting - Google Patents

Abstract

PURPOSE: To obtain an antibacterial decorative thermosetting resin laminate by applying an antibacterial composition containing a specified metal to a paper impregnated with a thermosetting resin and used for a surface layer of the decorative laminate and drying the composition to give a prepreg sheet and hot pressing this sheet put on a base plate. CONSTITUTION: This laminate is produced by applying an antibacterial composition containing an inorganic antibacterial agent carrying at least one antibacterial metal selected among silver, zinc and copper to the surface of a paper impregnated with a thermosetting resin and used for forming a first surface layer of the decorative laminate, drying the composition to give a prepreg sheet, and hot pressing this sheet put on a base plate to form an integral cured material. An example of preferable antibacterial compositions is one which consists of an inorganic antibacterial agent and a solvent, alone or together with a resin, and of which the inorganic antibacterial agent comprises at least one of a fired calcium-base ceramic power, a zeolite power and a silica gel power, each carrying the antibacterial metal(s).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an antibacterial thermosetting resin decorative board used for materials such as household appliances, furniture, and furniture. In particular, the thermosetting resin decorative board having antibacterial properties obtained by the present invention can obtain a sufficient antibacterial effect even if a relatively small amount of antibacterial agent is used, and antibacterial agents for hospitals, public facilities, cooking facilities, etc. It is useful for applications requiring sex.

[0002]

2. Description of the Related Art Thermosetting resin decorative boards are used for heat resistance, hardness,
Its excellent properties such as abrasion resistance, water resistance, and stain resistance have a wide range of applications, including warm and humid conditions such as bathroom walls, toilets, washbasins, kitchens, sinks, and tabletops. It is often used under conditions suitable for the growth of mold and bacteria due to adhesion and contamination. Further, in various facilities in hospitals, malignant Staphylococcus aureus (MRSA), which is resistant to antibiotics, is increasing, and nosocomial infections are becoming a problem.

However, a general thermosetting resin decorative board is more resistant to microbes such as mold and bacteria than a decorative laminated board made of a natural material, but depending on the environment in which it is used, these may not be used. It did not have the necessary antibacterial properties because it could not be prevented from being soaked, bred, or contaminated by the microorganisms.

Further, an inorganic antibacterial agent containing an antibacterial metal is mixed in a resin solution, and titanium paper is dipped in the mixed solution and dried to obtain an impregnated paper, and the impregnated paper is a plywood or fiber board. A method for producing an antibacterial decorative board by integrally heat-curing wood chips and other base materials is disclosed in JP-A-06-19.
8607 publication.

[0005]

Conventionally, a general thermosetting resin decorative board is often used in an environment suitable for the growth of bacteria, such as a hot and humid bathroom, a washroom, a kitchen, and kitchen equipment. In applications such as a dining room table, foods and other nutrients necessary for the propagation of bacteria are liable to adhere, and the use of ordinary veneer is not always preferable.

[0006] Furthermore, in the case of a decorative plate used in facilities in hospitals and geriatric facilities, malignant Staphylococcus aureus (MRSA)
It is easy to be exposed to the contamination of pathogenic bacteria such as that, and nosocomial infection has become a serious problem, and the use of an antibacterial decorative board has been desired.

In the method of adding an organic antibacterial agent to a thermosetting resin, the antibacterial agent is often harmful to the human body, is generally unstable to heat, and deteriorates in the heat molding process. The effect is likely to be lowered, and when used for a long period of time, it is easily affected by ultraviolet rays and the like. Further, there is a problem that the surface appearance of the decorative plate is impaired due to discoloration or the like.

An inorganic antibacterial agent containing an antibacterial metal is mixed with a thermosetting resin solution, titanium paper is dipped, impregnated and dried to obtain impregnated paper, and the impregnated paper is integrally heated to plywood and other base materials. In the pressure molding method, a resin containing an antibacterial agent is attached to both front and back surfaces of titanium paper, but the antibacterial agent in the resin adhered to the back side is effective against bacteria on the surface of the decorative sheet. It did not work and wasted expensive antimicrobial agents.

The present invention has the appearance and performance required as a thermosetting resin decorative board, does not easily discolor by heat or ultraviolet rays, and is efficient even when a relatively small amount of antibacterial agent is used. The purpose of the present invention is to obtain a decorative board having various antibacterial effects.

[0010]

The present invention provides a thermosetting resin-impregnated paper which constitutes the first layer on the surface side of a decorative board, after impregnating the paper with a thermosetting resin liquid A step of applying an antibacterial composition containing an inorganic antibacterial agent carrying at least one antibacterial metal of copper to the surface and then drying to obtain a prepreg sheet, and placing the prepreg sheet on a substrate A method for producing an antibacterial thermosetting resin decorative board, characterized in that the thermosetting resin of the thermosetting resin-impregnated paper is a melamine resin. , Diallyl phthalate resin, unsaturated polyester resin, acrylic resin, the inorganic antibacterial agent carrying an antibacterial metal, calcium-based ceramics firing powder, zeolite powder, sili Consists of at least one gel powder, further, the supported amount of antibacterial metal of the inorganic antimicrobial agent 0.2
10 to 10% by weight, and the inorganic antibacterial agent is 0.05 to 10 g /
The desired antibacterial thermosetting resin decorative board is efficiently obtained by applying the antibacterial composition so that the applied amount is m ² .

The thermosetting resin-impregnated paper forming the first layer on the surface side of the decorative sheet of the present invention forms the surface of the decorative sheet after molding. Specifically, the surface of the decorative sheet is protected. The overlay-impregnated paper of interest, or when the overlay-impregnated paper is not needed, as a decorative paper, a desired color, or a pattern, etc. impregnated with a titanium paper to which a design property has been impregnated with a resin,
It is a so-called loose pattern-impregnated paper.

As the overlay paper in the present invention, thin paper having a basis weight of 18 to 40 g / m ^{2 which} is transparent by impregnation with a resin is suitable, and the decorative paper is a mixture of titanium dioxide and a coloring pigment. The pattern is printed by gravure printing.

The above-mentioned overlay paper or pattern paper, which constitutes the first layer on the surface side of the decorative board, is first impregnated with a thermosetting resin liquid by a generally-used impregnation method to obtain an undried state. ,
Alternatively, after drying with hot air, the surface of the impregnated paper is coated with an antibacterial composition using a coating device such as a spray gun, a flow coater, or a roll coater, and then dried with hot air to form a decorative sheet. Get the prepreg sheet of.

The thermosetting resin used in the present invention has a good impregnating processability for paper in the form of a solution and can be made into a dry prepreg sheet by drying. Appropriate as a plate surface material can be obtained, and a desired prepreg sheet can be obtained by using at least one kind of melamine resin, diallyl phthalate resin, unsaturated polyester resin and acrylic resin. These resins are dissolved in water or an organic solvent such as methanol, acetone or toluene to impregnate overlay paper or pattern paper.

The antibacterial composition applied to the surface after overlay paper or pattern paper is impregnated with the above resin is an inorganic antibacterial agent added to a solvent or a solution consisting of the solvent and the above resin. It is preferable that the compounding amount be adjusted so that an antibacterial property is obtained, and the viscosity is adjusted so that the desired coating amount can be applied.

The inorganic antibacterial agent used in the present invention carries at least one kind of antibacterial metal such as silver, zinc and copper, and the amount of these antibacterial metals carried is from 0.2 to 10.
The inorganic antibacterial agent is used in an amount of 0.05 to 10 g / wt.
By applying the antibacterial composition so that the coating amount is m ² , excellent results can be obtained in terms of its antibacterial effect as well as its durability and discoloration resistance to heat.

When the amount of the antibacterial metal supported is 0.2% by weight or less, the amount of the antibacterial agent to be applied is large, so that the transparency of the surface resin layer of the decorative board is lowered, and the designability is easily impaired. ,
When it is 10% by weight or more, it is not economically advantageous and the appearance such as yellowing due to heat tends to deteriorate. The amount of the inorganic antibacterial agent applied is determined by the relationship with the amount of the antibacterial metal carried by the inorganic antibacterial agent, but if the amount applied is 0.05 g / m ² or less, uneven distribution and deterioration of the antibacterial property tend to occur. When it is m ² or more, the transparency of the resin layer on the surface layer of the decorative plate is deteriorated, and problems such as yellowing due to heat and deterioration of light resistance are likely to occur.

After applying the antibacterial composition, the impregnated paper is dried and, if necessary, wound in a long length or cut into a regular length to obtain a prepreg sheet having an antibacterial resin layer on the surface. obtain.

This prepreg sheet is placed on a base material and laminated by a conventional method, and hot pressing is carried out using a flat press hot press or a continuous press, to obtain an antibacterial thermosetting resin. Get a veneer.

As the base material used in the present invention, known base materials for thermosetting resin decorative boards can be used. Specifically, phenol resin, diallyl phthalate resin, unsaturated polyester resin can be used for paper such as kraft paper. , A method of using a so-called loose core impregnated paper impregnated with melamine resin or the like in a single layer or by laminating a plurality of layers.

A method in which a sheet material such as cloth or non-woven fabric is directly used as a substrate. Alternatively, plywood, medium fiber board, particle board, asbestos cement calcium silicate board, etc. may be used.

[0022]

EXAMPLES All parts and percentages shown below represent parts by weight and percentages by weight. Example 1 As a decorative paper, a white titanium paper having a basis weight of 100 g / m ² was condensed with a resin solution for melamine decorative board, which was condensed so that the molar ratio of formaldehyde and melamine was 1: 1.5. Impregnation was carried out so that the nonvolatile content was 100 g / m ² . next,
The antibacterial composition was applied before drying the resin-impregnated paper.

As the antibacterial agent, silver zeolite having a silver content of 2.5% and an ammonium ion content of 1.5% and an average particle diameter of 0.8 μm has a nonvolatile content of 5%. As described above, the antibacterial composition added to the melamine decorative board resin liquid is uniformly applied using an air spray gun so that the applied amount of the antibacterial agent is 3 g / m ² and 1
It was dried with hot air at 20 ° C. for 2 minutes to obtain a prepreg sheet-impregnated paper for decorative plate surface.

Unbleached kraft paper having a basis weight of 180 g / m ² was impregnated with phenolic resin so that the amount of non-volatile resin adhered was 110 g / m ² , and 5 sheets of impregnated paper for core were stacked on top of it. The above-mentioned impregnated paper for the surface of the decorative plate was overlaid, sandwiched between gloss-finished stainless steel plates, inserted between hot press hot plates, and thermocompression molded for 45 minutes under the molding conditions of temperature 140 ° C. and pressure 60 Kgf / cm ² . Then, it was cooled and taken out to obtain an antibacterial decorative plate having a thickness of 1.2 mm.

Example 2 As an antibacterial composition to be applied after impregnating a decorative paper with a melamine resin, the antibacterial agent used in Example 1 was 5% with respect to water.
The amount of antibacterial agent applied is 3 g /
An antibacterial melamine decorative board was obtained by the same manufacturing method as in Example 1 except that the antibacterial composition was applied so as to give m ² .

Example 3 The same production as in Example 1 except that the antibacterial composition was applied so that the amount of the antibacterial agent applied after impregnating the decorative paper with the melamine resin was 1 g / m ^2. An antibacterial melamine decorative board was obtained by the method.

Comparative Example 1 An antibacterial melamine decorative board was obtained by the same manufacturing method as in Example 1 except that the antibacterial composition was not applied after impregnating the decorative paper with a resin.

Comparative Example 2 An antibacterial melamine decorative board was obtained by the same manufacturing method as in Example 1 except that the antibacterial composition was applied so that the applied amount of the antibacterial agent was 12 g / m ² .

Comparative Example 3 An antibacterial melamine decorative board was obtained by the same manufacturing method as in Example 1 except that the antibacterial composition was applied so that the applied amount of the antibacterial agent was 0.02 g / m ² . . Examples 1 to 3
Tables 1 and 2 show the physical properties and antibacterial property test results of the decorative boards obtained in Comparative Examples 1 to 3.

[0030]

【Test method】

1. Physical property test for decorative board A test for appearance, boiling resistance, heat resistance, and light resistance is performed by the test method specified in the thermosetting resin decorative board test method (JIS K6902).

2. Antibacterial activity test (1) Test strain E. coli (E · Coli IFO 3301) and Staphylococcus aureus (Stap
hylococcus aureus IFO 12732) (2) Preparation of bacterial solution A test strain, which had been cultured as a single solution at 35 ° C. on an ordinary agar slant medium, was prepared using a sterilized phosphate buffer solution so that the number of bacteria was 10 ⁶ per ml. (3) Test operation Inoculate a specimen (50 mm x 50 mm) with 1 ml of the bacterial solution, and carry out at 35 ° C.
In Example 1, Example 2 and Comparative Example 1, SCDLP was stored at the start of storage and after 24 hours, and in Example 3, Comparative Example 2 and Comparative Example 3 at the start of storage, after 6 hours and after 24 hours. Surviving bacteria were washed out with 10 ml of medium (Nippon Pharmaceutical Co., Ltd.). The viable cell count of this wash-out solution was measured by the agar plate culture method (35 ° C. for 2 days) using a cell count measuring medium, and converted into the viable cell count per sample. Further, the same amount of the bacterial solution as that inoculated to the sample was dispensed into a petri dish and stored, and the viable cell count was measured to serve as a control.

[0032]

[Table 1]

[0033]

[Table 2]

[0034]

In the antibacterial decorative board, only the antibacterial agent contained in the surface layer acts effectively, and the antibacterial agent in the inner layer hardly contributes to the antibacterial effect. Inorganic antibacterial agents containing silver or the like are generally expensive, and the antibacterial agents contained in areas other than the surface layer of the decorative plate are wasted, resulting in a cost increase.

In the present invention, since the antibacterial resin layer is formed only on the surface of the thermosetting resin-impregnated paper forming the first layer on the surface side of the decorative plate, the resin liquid itself containing the antibacterial agent is formed. Compared to a molded prepreg impregnated with, the antibacterial agent is not wasted, and the desired antibacterial effect can be obtained by using a small amount of the antibacterial agent.

Further, the antibacterial agent used in the antibacterial decorative board of the present invention is safer in terms of toxicity and the like as compared with the one using an organic antibacterial agent, is stable against heat and the like, is resistant to discoloration, and is long-term. Even if it is used, its appearance and quality do not deteriorate, and it retains a continuous antibacterial effect.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location A01N 59/20 Z B29C 43/02 7365-4F B32B 27/00 9349-4F // B29K 105: 06

Claims (4)

[Claims] 1. A thermosetting resin-impregnated paper constituting the first layer on the surface side of a decorative board, which is obtained by impregnating a paper with a thermosetting resin solution and then at least one antibacterial property of silver, zinc or copper. Applying an antibacterial composition containing an inorganic antibacterial agent carrying a metal to the surface, and then drying to obtain a prepreg sheet, and placing the prepreg sheet on a base material and thermocompression molding A method for producing an antibacterial thermosetting resin decorative board, which comprises a step of curing and integrating by means of. 2. A calcium-based ceramic firing powder, a zeolite powder, wherein the antibacterial composition is composed of an inorganic antibacterial agent and a solvent or a solvent and a resin, and the inorganic antibacterial agent carries an antibacterial metal, respectively. The method for producing an antibacterial thermosetting resin decorative board according to claim 1, wherein the method comprises at least one kind of silica gel powder. 3. The thermosetting resin of the thermosetting impregnated paper forming the first layer on the surface side of the decorative board is at least one selected from melamine resin, diallyl phthalate resin, unsaturated polyester resin and acrylic resin. It exists, The manufacturing method of the antibacterial thermosetting resin decorative board of Claim 1 or Claim 2 characterized by the above-mentioned. 4. After impregnating the thermosetting resin liquid,
The amount of the inorganic antibacterial agent contained in the antibacterial composition applied to the surface is 0.2 to 10% by weight, and the inorganic antibacterial agent is applied in an amount of 0.05 to 10 g / m ² . 4. The method for producing an antibacterial thermosetting resin decorative board according to claim 1, wherein the antibacterial composition is applied so that