JPH10251562A - Electroconductive coating for electromagnetic wave shielding and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electroconductive coating for electromagnetic wave shielding that can be applied to an electromagnetic shielding material, an antistatic agent and the like, thus can improve the long-term quality stability and the productivity of the products, reduce its production cost and enables the diversification of new product development. SOLUTION: Bamboo materials as Sasa kurilensis, Phyllostachys bambusoides, Phyllostachys pubescens or Phyllostachys nigra are baked up at elevated temperature and thoroughly scoured to produce bamboo charcoal with a hexagonal porous structure. This charcoal is crushed with a crusher into fine particle powder. This electroconductive bamboo charcoal powder is mixed with, for example, titanium dioxide, chitosan, silk starch powder and the resultant bamboo powder is mixed with raw materials for coating to produce the objective coating mixture that can be applied to an appropriate base material in 21 coating layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is used for electromagnetic wave shielding materials, antistatic agents and the like in computer-related business, automobile-related business, home electric appliance-related, medical equipment-related, and the like, and is applied to the surface of various devices. The present invention relates to a conductive paint for electromagnetic wave shielding for producing a coated surface having high conductivity and a method for producing the same.

[0002]

2. Description of the Related Art Most of conventional conductive paints are mixed with metallic substances such as copper and nickel. In recent years,
A company represented by Three Bond Co., Ltd. has developed a conductive paint such as Three Bond Paint Acrylic 3350, 3350B or the like on the market.

[0003]

However, in the case of the conventional conductive paint, the product itself is extremely expensive in terms of production cost due to the inclusion of a metallic substance, and thus far, it has been used only in one field of industry. It could only be used, penetrating the end user and making it more accessible. Furthermore, it cannot be provided as an inexpensive paint at business sites such as various factories. In addition, the conventional conductive paint has problems that it has poor durability against oxidation, lacks long-term stability of the product, and is severe for the global environment. Furthermore, in various fields such as recent computer-related business, automobile-related business, home appliance-related, medical equipment-related, etc., while various types of electromagnetic interference are occurring frequently, electromagnetic shielding materials with advanced electromagnetic shielding performance,
For the purpose of being used as an antistatic agent or the like, it has been an issue to produce a coated surface having high conductivity and high electrical storage by applying it to the surface of various devices.

Accordingly, the present invention has been made in view of the above-mentioned problems, and can be applied to, for example, an electromagnetic wave shielding material, an antistatic agent, etc., thereby improving the oxidation durability and the long-term quality of the product. An object of the present invention is to provide a conductive paint for electromagnetic wave shielding that is friendly to the global environment and a method for producing the same, which enables improvement of stability and productivity, reduction of production cost, development of new products, and the like.

[0005]

In order to achieve the above-mentioned object, according to the present invention, bamboo materials such as root bent bamboo, bamboo bamboo, Meng Song bamboo, bamboo bamboo, etc. are baked at a high temperature and sufficiently aimed (refining).
Pulverizing the hexagonal porous structure bamboo charcoal into a fine powder, and mixing at least one of titanium dioxide, chitosan, silk starch, etc. with this conductive bamboo charcoal powder, Producing a bamboo charcoal paint by mixing bamboo charcoal powder and a coating raw material. In addition, bamboo materials such as root bent bamboo, bamboo bamboo, Meng Song bamboo, bamboo bamboo etc. are baked at high temperature, and bamboo charcoal with hexagonal porous structure made by sufficiently aiming (refining) is pulverized into fine powder. At least one of titanium dioxide, chitosan, silk starch, etc. was mixed with the conductive bamboo charcoal powder, and the bamboo charcoal powder was mixed with the coating raw material to create a paint that could be applied to any base material in a film form. A characteristic feature is a conductive paint for electromagnetic wave shielding.

In the conductive paint for electromagnetic wave shielding and the method of manufacturing the same according to the present invention, for example, the conductive paint for electromagnetic wave shield applicable to various products made of bamboo charcoal powder, which is a natural material, can be used, for example, to provide an electromagnetic wave shielding material. It can be applied as an antistatic agent, etc., enabling long-term quality stability and productivity improvement of products, reduction of manufacturing costs, development of new products, etc. In particular, because the paint itself is made of bamboo charcoal powder with a porous structure, in addition to the adsorption action, humidity control action to adjust the humidity in the air, mineral hot spring action, deodorant action, microwave,
It has an ion manipulation function that shields extremely low frequency electromagnetic waves and changes ions in the air from positive to negative, and neutralizes positive ion phenomena generated by environmental factors such as home appliances, office automation equipment, and mobile phones. At the same time, balance the air and maintain all equipment from electromagnetic interference.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

(How to make bamboo charcoal)
Shin bamboo, Moso bamboo, Tan bamboo, etc. are used. In particular, Moso bamboo, which can take bamboo shoots, is generally baked as black charcoal, but it is baked at a high temperature of about 1000 degrees C like white charcoal, enough The bamboo charcoal with the aim (refining) has properties similar to Bincho charcoal. Specific bamboo charcoal production
Baking in a black charcoal kiln or mechanical baking using a carbonization furnace is the mainstream method. Bamboo has a property that it has less tar content and more pyrolysis components than charcoal compared to charcoal. In particular, bamboo materials contain a large amount of hemicellulose, and a large amount of highly corrosive organic acids such as formic acid are generated in the initial components of thermal decomposition, so it is necessary to use materials such as stainless steel with excellent acid resistance for the carbonization furnace equipment. . And in the case of bamboo charcoal, about 4 low-temperature charcoal in the same kiln
00 ° C, medium-temperature coal is about 600 to 700 ° C, and high-temperature coal is about 1000 ° C or more. This bamboo charcoal baking process first starts with a smoking operation, which involves drying the steam while rotating it inside the kiln. It takes 3 to 4 days while raising the temperature of the kiln by about 1.5 degrees C. Do it. Next, in the carbonization operation, the carbonization takes about 40 to 50 hours, about half the time of charcoal, and the refining operation takes about 4 to 5 hours.

(Characteristics of bamboo charcoal) It has been confirmed by experiments that the combustion efficiency of bamboo charcoal drops to about one-third if it is used side by side, but the fire life is about three times that of charcoal if it is used vertically. ing. The ash content of bamboo charcoal is 2-4%, which is slightly higher than charcoal, especially silica content. Also, bamboo charcoal 1 produced by the above method
As shown in the structure of the photomicrograph of FIG.
It has a hexagonal porous structure and its surface area is about 200 to 300 m 2 per gram of bamboo charcoal.
Bamboo charcoal 1 (see FIG. 1a) baked at a high temperature close to degree C has about ten times the adsorption power of Bincho charcoal 2 (see FIG. 1b). Examination of the adsorption rate by an analysis method called the BET method reveals that in the case of Bincho charcoal 2, it is about 2 to 5 m 2,
Bamboo charcoal 1 baked at a high temperature of about C is about 50-60 m2. For comparison, a micrograph of pine charcoal (coniferous tree) 3 is shown in FIG. 1 (c). The innumerable pores P of the bamboo charcoal 1 are likely to be populated by useful microorganisms, and the microorganisms act as a habitat for the pores P, and the impurities adsorbed on the bamboo charcoal 1 cause dirt and odor in the air. And has the effect of decomposing harmful substances and the like. In addition, the bamboo charcoal 1 has various excellent properties such as air permeability and hygroscopicity, an infrared ray effect, a dehumidifying deodorizing effect, a negative ion effect, an electromagnetic wave shielding effect, a massage effect and the like.

(Results of analysis of bamboo charcoal) As shown in FIG. 2, according to the water quality test report, bamboo charcoal contains a large amount of silicic acid in addition to calcium, magnesium, sodium, potassium, etc. Understand. FIG. 3 shows the spectrum data of the bamboo charcoal by Raman spectroscopy.
There is a single peak with a relative intensity of m-1 indicating that the bamboo charcoal is made of pure carbon C. In addition, since the peak is quite sharp, it can be seen that there are almost no impurities.
Furthermore, the result of measuring the infrared emissivity of bamboo charcoal by FT-IR shows that the measurement temperature is about 39.8 to 39.9 ° C (JEOL FT-IR).
6500: IRR-200 measuring device is used). FIG. 4 shows reference comparison data for each of the two types of charcoal, such as long charcoal, oak charcoal, and miscellaneous wood, for each wave check by a resonance magnetic field analyzer (MRA).

[0011] As described above, bamboo is baked at a high temperature and sufficiently aimed (refined), and then bamboo charcoal having a hexagonal porous structure is pulverized into fine powder by a pulverizer to produce bamboo charcoal powder. Then, by mixing this conductive bamboo charcoal powder with, for example, titanium dioxide, chitosan, silk starch, and the like, and further mixing the bamboo charcoal powder with a coating material, a conductive paint having high conductivity and high stability for electromagnetic wave shielding is obtained. And
Simply applying various types of conductive paint for electromagnetic wave shielding using bamboo charcoal powder, which is such a natural material, to various products can shield electromagnetic waves and prevent generation of static electricity. For example, exterior parts of computer equipment, label sheets for word processors, ceramic substrates, fiber sheet base materials, air-permeable sheet members, bodies of automobiles, ships, airplanes, etc., exterior parts of home appliances, building materials, exterior parts of medical equipment, exterior parts of mobile phones If applied to the case or the like by spraying or brushing, it protects equipment from obstacles caused by external electromagnetic waves and prevents generation of static electricity. As a coating material, for example, as a paint containing a pigment, an oil-based or water-based paint or enamel, an oil-soluble paint using a synthetic resin as a coloring agent, a water-dispersible emulsion paint in which fine particles of a synthetic resin are emulsified in water, a paint color There are water-soluble paints in which carboxyl groups and the like in the agent are neutralized with amines, and varnishes that provide a transparent film without containing pigments include oil varnishes, resin varnishes, and alcoholic varnishes. In another embodiment of the present invention, for example, vegetable fiber such as natto fungus is used, silk powder is kneaded with the fiber, and hot water at about 50 ° C. to 60 ° C. is applied. Then, about 0.5% of titanium dioxide may be mixed with bamboo charcoal powder containing silicic acid and potassium to contain water.

[0012]

The present invention is configured as described above.
For example, it can be applied to electromagnetic wave shielding materials, antistatic agents, etc.
It is possible to improve the oxidation durability, improve the long-term quality stability and productivity of products, reduce manufacturing costs, develop new products, etc., and provide a conductive paint for electromagnetic wave shielding that is friendly to the global environment. . In particular, the conductive paint for electromagnetic wave shielding has an adsorption effect, a humidity control effect to adjust the humidity in the air,
In addition to mineral hot spring action and deodorant action, it has the function of shielding microwaves and ultra low frequency electromagnetic waves, and the ion manipulation action of changing ions in the air from positive to negative, and is used for home appliances, OA equipment, mobile phones, etc. By neutralizing the positive ion phenomenon caused by environmental factors, the air can be balanced and at the same time, all equipment can be maintained from electromagnetic interference.

[Brief description of the drawings]

FIG. 1 is a configuration diagram based on a micrograph showing an embodiment of the present invention.

FIG. 2 shows a water quality test result.

FIG. 3 is also spectral data of bamboo charcoal by Raman spectroscopy.

FIG. 4 shows an MRA check test result.

[Explanation of symbols]

 P… Pore 1… Bamboo charcoal 2… Bincho charcoal 3… Pine charcoal

Claims (2)

[Claims] 1. A hexagonal porous structure bamboo charcoal made by baking bamboo materials such as root bent bamboo, bamboo bamboo, meng bamboo bamboo, and bamboo bamboo at a high temperature and sufficiently aiming (refining) into fine powder. And mixing the conductive bamboo charcoal powder with at least one of titanium dioxide, chitosan, silk starch and the like, and mixing the bamboo charcoal powder with a coating material to form a bamboo charcoal paint. A method for producing a conductive paint for electromagnetic wave shielding, comprising: 2. A hexagonal porous structure bamboo charcoal made by baking bamboo materials such as root bent bamboo, bamboo bamboo, meng bamboo bamboo, and bamboo bamboo at a high temperature, and sufficiently sintering (refining) into fine powder. Then, titanium dioxide, chitosan,
A conductive paint for electromagnetic wave shielding, wherein at least one of silk starch and the like is mixed, and a bamboo charcoal powder and a coating material are mixed to prepare a paint that can be applied in a film form to an arbitrary base material.