JPS647007B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a carbonized carbon sheet and a method for producing the same, and more specifically, carbonized carbon sheets made of carbonized carbon sheets selected from phenolic resins, melamine resins, and urea resins among thermosetting resins.
The present invention relates to a carbonized carbon sheet made by impregnating a fiber cloth with a three-component dispersion of mixed resin powder and hard carbon powder, and heating and firing the fiber cloth under pressure, and a method for producing the same. [Prior art] Conventionally, fiber paper or cloth is coated (impregnated) with a coating liquid consisting of a solvent solution of a thermoplastic synthetic resin or its copolymer or a thermosetting synthetic resin, etc., and carbon black, and then heated or heated and pressurized. Various materials and methods for producing the same are known. For example, Japanese Patent Publications No. 13057/1983, Japanese Patent Publication No. 23591/1982, and Publication No. 38949/1987 have been published on fabrics using thermoplastic resins or copolymers thereof, and furthermore, they have been published in Japanese Patent Publications No. 51-13057, Japanese Utility Model Publication No. 51-38949, using thermosetting resins or their copolymers. Tokuko Sho 59 on the impregnated material.
There are publications such as No. 2843. [Problems to be Solved by the Invention] However, although conventionally known products of this kind can be provided with certain desired physical properties, they do not have the electrical conductivity performance and mechanical strength that are intended by the present invention. It has excellent flexibility, water resistance, heat resistance, flame resistance, etc., and cannot be said to be weather resistant. Therefore, it cannot be used as an interior material for adhesion to ceilings, walls (including wainscoting, floorboards), etc. Moreover, it is not suitable for so-called multi-purpose use, where it can simultaneously exhibit the above-mentioned characteristics by being applied as an underlay, or as an exterior material or other radio wave shielding material, for example, to the inner wall of a broadcasting room in a broadcasting station or a radio room in a ship. Therefore, from this point of view, in order to satisfy some of the above characteristics at the same time, at least some kind of secondary measures (processing) corresponding to the purpose of use are required. There were always problems in terms of quality and cost, and there were also technical problems in manufacturing. [Means for Solving the Problems] As a result of conducting various experimental studies to solve the above-mentioned problems, the inventors have developed a thermosetting resin selected from phenolic resins, melamine resins, and urea resins. Two-part mixed resin (both powder)
By selecting these three types, consideration was given to complementing or aggravating the advantages and disadvantages of the characteristics of the two, and in addition, by effectively utilizing the electrical conductivity peculiar to carbon, hard carbon powder Based on the viewpoint that electrical conductivity can be further improved by mixing a predetermined amount of carbon black (not carbon black), we developed a coating liquid (described below) consisting of these mixed powders (three-component powder). ) was impregnated into a fiber cloth and then heated and fired under pressure to examine the physical properties of a carbonized carbon sheet, which was found to have almost all of the desired electrical conductivity, mechanical strength, and other properties. It was confirmed that the above-mentioned defects could be solved at once, and the present invention was completed. The first feature of the present invention is that hard carbon powder is mixed with each of the two-component mixed resins, and the second feature is that the three-component mixed powder obtained as described above is mixed with hard carbon powder. Impregnate the fiber cloth with the dispersion,
This is heated and fired under pressure to form a carbonized carbon sheet. That is, in the present invention, one or three of the two-component mixed resin powder of phenolic resin and melamine resin, phenol resin and urea resin, and melamine resin and urea resin selected from phenolic resin, melamine resin, and urea resin is hard carbon powder. The present invention relates to a carbonized carbon sheet in which a fiber cloth impregnated with a dispersion of a three-component mixed powder mixed with a carbon fiber is heated and fired under pressure. 2 consisting of a phenolic resin and a melamine resin, a phenolic resin and a urea resin, and a melamine resin and a urea resin selected in the invention.
Hard carbon powder is mixed with one or three of the mixed powder components, the three-component mixed powder is dispersed in a solvent in the presence of a basic curing agent, and the dispersion is impregnated into a fiber cloth. After drying, the impregnated fiber cloth is heated and fired under pressure. The purpose of the present invention is to have excellent electrical conductivity and mechanical strength (compressive strength, tensile strength, shear strength), flexibility, water resistance, heat resistance, flame resistance, etc., and good weather resistance. It is an object of the present invention to provide a carbonized carbon sheet suitable for various multi-purpose uses at a low cost, and to generally provide a method for manufacturing the same. Each of the thermosetting resin powders used in the present invention has a particle size of 100 to 200 μm obtained by separately grinding and sieving each resin by a conventional method (using a roll mill or ball mill), For the hard carbon powder, a powder with a particle size of 120 to 250 μm obtained by pulverizing a single phenol resin or furfural resin (or a mixture may be used) as described above is electro-sintered in an inert gas atmosphere. Particles with a particle diameter of 110 to 120 μm are used after being heated and fired in a furnace. However, the mixing ratio of the two-component mixed resins that make up the phenolic resin and melamine resin mixed powder, the phenolic resin and urea resin mixed powder, and the melamine resin and urea resin mixed powder is fixed depending on the use and purpose of the product. However, they are usually mixed in a ratio of 100 to 120:100 to 80 parts by weight in a conventional manner. Furthermore, the above 2
Mixing of component-based mixed resin powder and hard carbon powder is carried out by a conventional method, but the mixing ratio varies depending on the product use and purpose as described above. ) 30 to 50 parts by weight, preferably 35 to 50 parts by weight, per 100 parts by weight. In this case, if the blending ratio of hard carbon powder is less than 30 parts by weight, mechanical strength and water resistance may be obtained, but electrical conductivity will be lower than desired, and heat resistance and flame resistance will tend to be lacking. is large, and the increased flexibility makes it unsuitable for practical use. If the blending ratio exceeds the upper limit (50 parts by weight), it is possible to improve the electrical conductivity, heat resistance, flame resistance, etc., but as the curing progresses, it becomes hard and brittle, leading to a significant decrease in flexibility. It's not practical. In the above, each mixed resin powder and hard carbon powder may be mixed by mixing the latter with the former, or by mixing each resin constituting the former and the latter at the same time at the required blending ratio in advance. You can. The selection of phenol resin, melamine resin, and urea resin as the thermosetting resin used here is based on various experiments conducted by the inventor leading to the completion of the present invention. This is based on the viewpoint that it is easier to obtain at a relatively low cost than other resins of this type and their solvents, has less complexity in the manufacturing process, and can provide products with desired characteristics at low cost. The three-component mixed powder obtained as described above is
110 to 150 parts by weight, preferably 120 to 140 parts by weight of a solvent such as methyl alcohol, ethyl alcohol or butyl alcohol (heated at 20°C) per 100 parts by weight, in the presence of a basic curing agent such as ammonium chloride, in a conventional manner. However, in this case, two of the three components, the resin, dissolve and become liquid, but on the other hand,
Alcohol-insoluble hard carbon powder is dispersed into C.
A viscous coating liquid with P.400 to 500 is obtained, and a coating liquid with good adhesiveness and desired properties in addition to electrical conductivity is obtained (first
(see figure). In this case, known dispersants (hexametaphosphate), penetrants (alkyl sulfonates),
One or more of a release agent (stearate) and a filler (talc, bentonite) can also be added. However, in the above, if the amount of solvent used is less than 110 parts by weight based on the mixed resin, uniform impregnation of the fiber cloth (described later) cannot be obtained due to an increase in viscosity, which is unsuitable from both a quality and practical standpoint. Also, the amount of solvent used
If the amount is 150 parts by weight or more, the above points can be avoided, but
Since the desired consistency cannot be obtained, the impregnation of the fiber cloth is limited to mere impregnation, and it is difficult to impart the desired properties to the fiber cloth, particularly electrical conductivity and mechanical strength. I can't. The fiber cloth to be used may be a cotton cloth, a mixed woven cloth woven with natural fibers and synthetic fiber threads, or a nonwoven cloth made of synthetic fibers, and it does not matter whether the weave is coarse or dense. For example, it can be used regardless of plain weave or twill weave, ranging from net-like to closed-weave. However, it is preferable that the fabric is not too woven and that the impregnation time with the coating liquid is relatively short. The above three-component dispersion (coating liquid) on the above fiber cloth
To impregnate the fiber cloth, roll-wound fiber cloth is soaked in a basic curing agent for 20 minutes using a conventional method (dipping method).
The coating liquid heated to ℃ is continuously passed through a rotating roll (or rolls may be multiple) in a vat, impregnated with the coating liquid, and the excess coating liquid is squeezed out via a squeezing roll. do it. In this case, it goes without saying that the degree of impregnation of the coating liquid into the fiber cloth depends on the viscosity of the coating liquid and the length of the impregnation time. An impregnation time of 2 to 5 minutes is sufficient. This impregnated cloth was then dried in a drying oven (100°C constant temperature) as described below.
After being passed through to volatilize the solvent, it is passed to a primary hot roller press (hereinafter referred to as the first press), and then to a secondary hot roller press (hereinafter referred to as the second press), where it is heated and fired under pressure. When the impregnated resin is cured, a long carbonized carbon sheet with a smooth surface is obtained, which is then wound into a winder or cut into flat sheets (see Figure 2). The thickness of the sheet obtained above can be determined by adjusting the impregnation amount of the coating liquid (three-component system), the roller pressure during firing, etc. within the range of the above conditions, taking into account the thickness of the fiber cloth. It can be obtained from thin sheets to thick sheets. However, in the above, the purpose of passing the fiber cloth impregnated with the coating solution through the first and second presses in sequence is to accelerate the curing of the resin in advance in the first press and at the same time obtain a smooth surface after firing. The roller pressure (linear pressure: the same applies hereinafter), temperature, and time at this time cannot be constant depending on the use and purpose of the product and the amount of coating liquid impregnated into the fiber cloth, but it depends on the amount of impregnation into the fiber cloth. is 800g/ ^m2 and the thickness of the carbonized carbon sheet after the second press is 0.5-0.6mm, the roller pressure is usually 50-60Kg/cm and the temperature in the first press.
The primary resin curing and baking are promoted at 120-130°C for 2-3 minutes. The conditions for the second press are the roller pressure
Firing is completed in 2 to 3 minutes at a temperature of 70 to 150 kg/cm, a temperature of 140 to 150°C, and a smooth carbonized carbon sheet is obtained. The conditions in this case, namely the roll pressure, temperature and time, are interrelated within the ranges mentioned above, and if any of them deviates from the above ranges, not only will it be impossible to obtain a product of the desired high quality, but also the desired physical properties will not be obtained. cannot be equipped with. [Effects of the Invention] (1) The present invention provides a two-component mixed powder consisting of a phenolic resin and a melamine resin, a phenolic resin and a urea resin, and a melamine resin and a urea resin selected from phenolic resins, melamine resins, and urea resins. Or a dispersion liquid in which hard carbon powder is mixed with the three components and the three-component mixed powder is dispersed in a solvent in the presence of a basic curing agent (heated at 20°C)
It is obtained by impregnating a fiber cloth, drying the impregnated fiber cloth, and then heating and baking it under pressure.
In this case, since the dispersion liquid is impregnated into the fiber cloth as an adhesive binder in which hard carbon particles are dispersed, there is no peeling of carbon particles from the carbon sheet after firing. (2) Carbonized carbon sheets obtained from a three-component system consisting of phenolic resin, melamine resin, and hard carbon not only have high electrical conductivity due to the electrical properties of the phenolic resin and the intervening hard carbon particles. , has high mechanical strength supported by the durability (toughness) of phenolic resin,
Moreover, the water resistance is improved by adding water resistance of both of the resins, and at the same time, heat resistance is imparted by the melamine resin, and flame resistance is achieved by the presence of hard carbon particles. Furthermore, the phenolic resin complements well the brittleness of the flexible melamine resin when it is cured, giving it appropriate flexibility. (3) The carbonized carbon sheet obtained from the three components of phenolic resin, urea resin, and hard carbon has high electrical conductivity due to the electrical properties of the phenolic resin and the intervening hard carbon, as in (1) above.
Furthermore, the mechanical strength is high supported by the durability of the phenolic resin, and at the same time, the water resistance can be further increased due to the combination of the great water resistance of the urea resin and the water resistance of the phenolic resin. Heat resistance is imparted by the urea resin, and flame resistance is improved by the presence of hard carbon particles as in (1) above. Furthermore, the flexibility is appropriately adjusted by the phenolic resin. (4) Carbonized carbon sheet obtained from three components: melamine resin, urea resin, and hard carbon,
Good electrical properties (conductivity) are obtained due to the electrical performance of the melamine resin and hard carbon particles, and at the same time, mechanical strength is complemented by the melamine resin, and water resistance and heat resistance are improved by the melamine resin. It is complemented and has appropriate flexibility. Also, as in (1) above, flame resistance is improved by the presence of hard carbon particles. (5) The product of the present invention is suitable for continuous (consistent) production and does not require complicated special equipment, so it can be provided at low cost, and as described above, the product has the desired characteristics. Since it is equipped with almost everything, it can be used as an interior material for ceilings,
In addition to adhering to walls (including wainscoting and floorboards) or underlaying them, when installing or underlaying on or under tatami mats, or when using in beds or mats, the above products are of excellent electrical quality. properties and mechanical strength, as well as being flexible, water resistant, heat resistant, flame resistant and weather resistant, making it compatible with the surface to which it is applied and therefore easy to install or adhere. Furthermore, even if there is high humidity after application, since it does not absorb moisture, mold and the like will not form and corrosion of the base material to which it is applied will be completely eliminated. Furthermore, when this material is used as a substitute for carbonaceous materials conventionally used in house construction sites, it is possible to prevent corrosion of foundation materials and related materials. Furthermore, when this product is buried in the soil as a long sheet or a sheet cut into an appropriate size such as a flat sheet as necessary, it will be effective as a soil improvement material due to the electrical properties of the sheet. You can also do so. What is particularly effective about this product is that it can effectively block radio waves due to the above-mentioned electrical properties, so when it is applied to the inner wall of a broadcasting station (including a broadcasting room), the radio room of a ship, etc. It can be used as the most effective radio wave blocking material, and can exhibit unique effects suitable for multipurpose uses. [Example] An example of the present invention is shown in Fig. 2 (schematic manufacturing process diagram).
Explain with reference to. A long cotton cloth (or a non-woven cloth formed in a mesh shape may be used) 2 wound around a winder 1 is passed through a guide roller G and a stretch roller S to pre-mix phenolic resin powder and melamine resin powder (particles). 30 to 50 parts by weight of hard carbon powder (particle size 110 to 120 μm) are mixed with 100 parts by weight of a mixed powder consisting of 100 to 80: The carbon powder dispersion obtained by mixing the mixed powder with 110 to 150 parts by weight of methanol (heated at 20°C) in the presence of ammonium chloride.
In a vat 4 containing a viscous liquid 3 of P.400 to 500, the viscous liquid is guided to a roller 5 (more than one may be used; see figure A) made of an alkali-resistant metal or synthetic rubber that rotates as shown in the figure, and then applied to a cotton cloth 2. 3 is sufficiently impregnated, and the excess impregnating liquid (viscous liquid) impregnated into the cotton cloth 2 through the ironing rollers 6, 6 and the attached liquid 3 adhering to the surface of the impregnated cloth are squeezed off to eliminate uneven impregnation and achieve uniform impregnation. After that, the impregnated cotton cloth 2a is kept at a constant temperature (100
°C) into a drying oven (the heat source can be either electric heat or steam, and this figure uses the former) to volatilize the methanol contained in the impregnated cotton cloth 2a (this volatilized methanol is always exhausted to the outside of the furnace). The vaporized gas is absorbed by the absorbent material by suction into a tank (plurality: not shown) containing the absorbent material by method or other appropriate means). Next, the impregnated cotton cloth 2a impregnated with the viscous liquid 3 after demethanolization is introduced into the first press 8 installed in the hood 11. As shown in the figure, this first press 8 consists of metal heating rollers 8a, 8a of the same diameter that rotate in the same direction within a hood 11, and has a surface temperature of 120 to 130°C (the heat source may be either electric heating or steam). The figure is based on the former) and is introduced between the rollers of the
It takes 3 minutes to fire the resin while promoting hardening of the resin and degassing the carbon odor generated during hot pressing to obtain the primary carbonized carbon sheet 10a which still has a rough surface. After that, the sheet 10a is attached to the hood 1 as described above.
The press 9 is introduced into a second press 9 installed within the interior of the press 1. Like the first press, this second press 9 has a metallic heating roller 9 that rotates in the same direction within the hood 11 and has the same diameter.
It is introduced between rollers with a surface temperature of 140 to 150°C (the heat source can be either electric heating or steam, and this figure is based on the former), and is placed between two to three rollers under a roller pressure of 70 to 150 kg/cm. It took several minutes to complete the firing of the primary carbonized carbon sheet and obtain the desired product 10. The results are shown in the following table for each example. 【table】

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an example of the coating liquid preparation process required in the production of the present invention, Fig. 2 is a schematic explanatory diagram showing the production process of the present invention, and Fig. 2A is a vat containing the viscous liquid. FIG. 2 is a schematic explanatory diagram showing a state in which a long cotton cloth is impregnated with a viscous liquid through a plurality of rollers rotating therein. 1... Winder, 2... Cotton cloth, 3... Viscous liquid (coating liquid), 4... Butt, 5... Roller, 6...
Ironing roller, 7... Drying oven, 8... First press, 8a... Press roller, 9... Second press, 9a... Press roller, 10... Carbonized carbon sheet (final product), 11... Hood .

Claims (1)

[Claims] 1. A phenolic resin and a melamine resin selected from phenolic resins, melamine resins and urea resins,
1 to 3 of two-component mixed resin powder of phenolic resin and urea resin and melamine resin and urea resin
A carbonized carbon sheet characterized in that a fiber cloth impregnated with a dispersion of a three-component mixed powder mixed with hard carbon powder is heated and fired under pressure. 2. Phenol resin and melamine resin selected from phenolic resin, melamine resin and urea resin,
Hard carbon powder is mixed with one or three of the two-component mixed powder of phenolic resin, urea resin, and melamine resin and urea resin, and the three-component mixed powder is dissolved in a solvent in the presence of a basic curing agent. A method for producing a carbonized carbon sheet, which comprises dispersing the dispersion, impregnating a fiber cloth with the dispersion, drying the impregnated fiber cloth, and then heating and firing it under pressure.