JPS62288163A - Manufacture of carbonated inorganic formed body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Technical Field of the Invention) The present invention relates to a method for producing a carbonized inorganic molded article, and more particularly, to a method for producing an inorganic fibrous material and a powdery and/or fine fibrous inorganic material. A phenolic resin is pre-contained in a molded article formed by molding an aqueous dispersion containing as a main component a mixture of 10010 to 10/90 in a weight ratio of The present invention relates to a method for producing a carbonized inorganic molded product, which is characterized by carbonizing the phenolic resin by baking in a reducing atmosphere.

(Prior art and problems) It is a known technology to carbonize phenolic resin by firing it in a reducing atmosphere.For example, it has been applied to activated carbon fibers, graphite-based sliding materials, refractories, etc. ing.

These conventional methods for producing carbonized products include kneading phenolic resin and aggregate (for example, clay) and going through the steps of → molding → hardening → firing, and kneading → drying → pulverization → molding → hardening → firing. It is known that some products go through a process called "ceramics", but these manufacturing methods are the same as those for manufacturing so-called ceramics, and carbonized products made by this method are usually called glassy carbon and have properties similar to glass. It had drawbacks such as being brittle and easily cracking.

(Means for Solving the Problems) The present inventors have made extensive studies to solve the problems of the prior art, and as a result, have completed the present invention.

That is, the present invention uses inorganic fibrous material and powdered and/or
or fine fibrous inorganic material in a weight ratio of 10010 to 10/90 as the main component, and further contains an organic binding component, a stringable polymer, an oil-resistant agent, a water-resistant agent, a coupling agent, etc. as necessary. In addition, by forming an aqueous dispersion into a molded product using a wet papermaking method or a method similar thereto, incorporating a phenol resin into the molded product, and carbonizing the phenolic resin by thermosetting and firing in a reducing atmosphere. The drawbacks of conventional technology, such as ease of breakage and brittleness, have been overcome. Examples of the inorganic fibrous materials used in the present invention include glass fiber, micro rascoole, rock wool, mineral wool, alumina silica fiber, alumina fiber, mullite fiber, boron fiber, quartz fiber, fused silica fiber, and potassium titanate fiber. , stainless steel fiber, carbon fiber, etc., but are not limited to these. These inorganic fibrous materials are expected to have a fiber reinforcing effect, and the average rut fiber length is preferably 100 μm or more. Further, powdered and/or fine fibrous inorganic materials that may be used as necessary include silica stone, silica sand, diatomaceous earth, Kibushi clay, Frog's eye clay, kaolin, no-leupite, montmorillonite, and +'l teakide. , bentonite, zeolite, phosphate rock, diaspore, gibbsite, clay mica (sericite, illite) vermiculite, acid clay, pottery stone, waxite, feldspar, limestone, wollastonite, gypsum, dolomite, magnesite, talc, etc. Natural products, metal hydroxides such as aluminum hydroxide, magnesium hydroxide, ferric hydroxide, calcium silicate hydrates, calcium aluminate hydrates, calcium sulfoaluminate hydrates such as topelmonite and xonotrite Hydrates of various oxides such as alumina, silica, magnesia, calcia, zirconia, doria, beryllia, titanium oxide,
Spinel, synthetic cordierite, synthetic mullite, synthetic zeolite, synthetic calcium carbonate, calcium phosphate, various carbides (TiC, ZnC, etc.)

HfC* VeC, TaC, NbC* WC, B4C,
StC, etc.), various nitrides (TIN, V'N, NbN
, TaN, HfN, AbN, BN, Si3N4, etc.),
Lithium oxide, ferrous oxide, ferric oxide, lead oxide, zinc oxide, nickel oxide, manganese dioxide, cupric oxide, cobalt oxide, vanadium oxide, beryllium carbonate, manganese carbonate, mountain bark (sepiolite, attapulgite, palygorskite) ), hydrated swelling mica (sodium tetrasilisichmica, indium or lithium taeniolite,
Sodium or lithium hectorite, etc.), metal titanate (potassium titanate, calcium titanate, sodium titanate, barium titanate, strontium titanate, magnesium titanate, etc.), graphite, activated carbon, carbon black, carbon fiber, metal Powder, powder of artificial inorganic substances such as various inorganic pigments, or powder with a length of approximately 10
Examples include fine fibrous materials with a diameter of 0μ or less. Note that whiskers, scale-like substances, and flake-like substances are also included. These inorganic materials are appropriately selected and used depending on the required function of the molded article after firing. The usage ratio of inorganic fibrous material is inorganic fibrous material/inorganic powder (and/or fine fiber) = 10
A range of 0.010 to 10/90 is appropriate.

In addition to these components, organic binding components that may be added as necessary include long fibers for washi paper such as wood norzo, mitsumata, and kozo obtained from coniferous trees and broad-leaved trees;
Synthetic products such as natural fibers such as hemp and cotton, as well as vinylon, nylon, acrylic, polyester, propylene, polyvinyl chloride, polyfural, human silk, PVA fiber, etc. ! Examples include textiles.

Furthermore, water-soluble urea resin, melamine resin,
Cationized starch, CMC, polyamide polyamine epichlorohydrin resin, ? Wet paper strength agents such as Liimin resin and water-soluble acrylic resin, rosin-based sizing agents, petroleum-based sizing agents, maleic acid-based sizing agents, polymer resin emulsions, latex, and anionic polymer coagulants for stringing. Pa? Limers (e.g. sodium polyacrylate, salts of partial hydrolysates such as polyacrylamide, salts of maleic acid copolymers), cationic polymers (e.g. partial hydrolysates of polyacrylamide, etc.), nonionic polymers ( Examples: polyacrylamide, polyvinyl alcohol,
Natural stringy polymers such as PEO) 6-luor or molasses may also be used.

In addition, fluorine-based oil-resistant agents/mold release agents, silicone-based water repellents/mold release agents, silane coupling agents, sulfuric acid clay, sodium aluminate, sodium polyphosphate, ammonium polyphosphate, etc. can be added.

It is desirable that the amount of additives other than these inorganic substances be as small as possible, 20% by weight or less.

The molded product of the present invention includes the above-mentioned inorganic fibrous materials, inorganic powders,
After dispersing inorganic fine fibers, organic binding components, and optionally added additives in water, a sheet-like or complex three-dimensional unfired molded product is formed by a wet papermaking method or a method similar thereto. Here, the wet papermaking method or a method similar thereto refers to a method in which the aqueous dispersion is poured onto a filter medium such as a strip-shaped, cylindrical, or square-shaped filter screen, filter cloth, or filter plate. This is a general term for a method in which a molded product is obtained by filtering the product, for example, by natural filtration or vacuum filtration after sandwiching it with these filtration media. The molded product obtained in this manner is dried after being peeled off in an F-heating medium, or dried and then peeled off to become a molded product through a drying process. Methods for continuously carrying out these forming processes in the form of sheets include conventionally known wet paper machines such as the Fourdrinier type, the circular mesh type, the cylinder former set, and the diagonal wire mesh type. On the other hand, as a method for intermittently performing these moldings into a three-dimensional object, there is, for example, a pulp molding method. Furthermore, there is also a method in which the above-mentioned sheet-like material is rolled into a paper tube shape, cut, pasted, stacked, bent, folded, and then subjected to secondary processing and molded. The thus obtained molded product is impregnated with 7-enol resin, heated and cured, and then fired in a reducing atmosphere.

Alternatively, after impregnating with a phenol resin, secondary molding may be performed and then heat curing may be performed. In addition, a necessary amount of powdered cylophenol resin may be mixed in the paper making process and then added to the paper making process.

The content of the phenolic resin is controlled depending on the amount of residual carbon in the phenolic resin or the required functions of the molded product after carbonization. In addition to pure phenol resin, the types of phenolic resins include resorcin modified resin, cresol modified resin, rose alkyl phenol resin, cashew modified phenol resin, aromatic hydrocarbon resin, modified resin, melamine modified resin, urea modified resin, and oil modified resin. , furan-modified resins, aniline-modified resins, lignin-modified resins, epoxy-modified resins, etc. In addition, there are resol type and tumelac type of these resins. It is appropriately selected from these as necessary. Firing in a reducing atmosphere may be carried out in nitrogen gas, or even in the presence of oxygen, the molded body may be placed in a closed box, sprinkled with coke powder, etc., and then steamed.

(Effects of the Invention) The carbonized inorganic molded product thus obtained has significantly stronger physical strength, thermal strength, etc. than those of the prior art, and can be used as a heat-resistant material, a friction material, a conductive material, etc. It can now be applied to a wide range of applications, including infrared radiation materials, chemical-resistant materials, and sliding materials.

(Example) Next, the present invention will be specifically explained with reference to Examples.

Example 1 and Comparative Example 2 Sheets made using a wet papermaking method with a thickness of 0.3 mm and mainly composed of ceramic fibers (Corselan C-30 manufactured by Kojin Co., Ltd.)
After impregnating 50 layers of phenolic resin straight resin (manufactured by Sumitomo Duress) and drying, 100XX1
Stack 20 sheets cut to size 00X to make 1
Hot pressing was carried out at a temperature of 50°C. 3 vm jl after pressing
It became a board. This plate was sealed in a stainless steel box with a lid, and while it was filled with coke powder, the temperature was gradually raised to 1200° C. in an electric furnace, maintained for 2 hours, and then cooled, and the plate was removed.

On the other hand, as a comparative example, kaolin clay and the phenolic resin used in Example 1 were kneaded at a ratio of 1:1, and a thickness of 3III was obtained.
The material was molded into a plate shape of I, dried and cured by heating at 150°C, and then subjected to reduction firing in the same manner as in Example 1, and the physical properties of the finished plates were compared. The results were as shown in Table-1.

From the results in Table 1, it is clear that the sample 7'' of Example 1 according to the present invention is significantly superior to the conventional product (San 7'AI of comparative example 1) in all aspects of the tested items. It became.

Example 2 and Comparative Example 2 Mullite fiber (manufactured by Mitsubishi Chemicals, average fiber length 3 tm
K Fjr4) 100 parts by weight and wood/# A/ 7
'5 parts by weight of colloidal bentonite and 10 parts by weight were dispersed in water and molded into a crucible shape by a pulp molding method. To this, the same phenolic resin as in Example 1 was added at a content rate of 3011.
It was impregnated in an amount of L, and after drying, it was heated and cured at 160°C. Then, it was fired at 1600° C. in a reducing atmosphere in the same manner as in Example 1. On the other hand, as comparative example 2, comparative example 1
The same kaolin clay and phenol resin were kneaded in a ratio of kaolin clay phenol resin = 7/3, molded into a crucible shape, dried and cured by heating at 160°C, and then reduced and fired in the same manner as in Example 2. The results of comparing the performance of the completed crucibles are shown in Table 2.

Table-2 0υ0 Shrinkage rate after firing...measured by volume of water 0
Heat shock resistance...Zero drop test in which something heated to 1200℃ is rapidly cooled...The crucible is dropped from a height of 30cm onto a concrete floor.

Claims (1)

[Claims] An aqueous dispersion containing as a main component a mixture of an inorganic fibrous material and a powdery and/or fine fibrous inorganic material in a weight ratio of 100/0 to 10/90 is prepared by wet papermaking method or the like. 1. A method for producing a carbonized inorganic molded article, which comprises incorporating a phenol resin into a molded article molded by a similar method, heat-curing it, and then firing it in a reducing atmosphere to carbonize the phenol resin component.