JPS60208237A - Heat-resistant sheet and manufacture thereof - 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 This product is a heat-resistant sheet using organic flame-resistant fibers, a heat-resistant fireproof paper, and a heat-resistant puffing material.

F17 is used in a wide range of applications such as heat-resistant materials for rolls and noncombustible building materials.

Conventionally, many proposals have been made for these heat-resistant sheets.

For example, sheets made of inorganic fibers such as asbestos and glass fibers by wet paper-making, dry paper-making, and other manufacturing methods are conventionally known. However, those using these inorganic fibers each have their own drawbacks. For example, the use of asbestos is regulated due to its carcinogenic properties, and glass fiber is irritating to the skin and lacks yellowing properties. Also, inorganic fibers in general? The sheets used generally have insufficient sinterability and are highly hard, so when used for applications that rub against soft materials, they have disadvantages such as damaging the surface, such as oxidized fibers, novoloid fibers, Heat resistance of aromatic gelamide fibers, etc.
Examples include flame-resistant fibers.

Oxidized fibers are usually obtained by oxidizing polyacrylonitrile fibers at 200-1-400°C in an oxidizing atmosphere. Novoloid fibers are usually obtained by melt-spinning a novolac type phenolic resin and then subjecting it to a curing reaction. Aromatic polyamide fibers can be made into fibers by wet spinning, melt spinning, liquid crystal spinning, dry-wet spinning, etc. can get.

The water-swellable mineral used in the present invention is an inorganic compound having a crystal structure in which the crystal unit cell is repeated in the thickness direction, and has the property of swelling by incorporating water molecules in the crystal layer, and this swelling property is most developed. At this stage, the crystals collapse into ultrafine particles and form a stable lump in water.For example, water-swellable bentonite group (e.g. colloidal bentonite, colloidal sodium montmorillonite, etc.) Natural products such as water-swellable mica group (1+1
Examples include, but are not limited to, compounds such as 1: sodium tetrazolithium, sodium or halitium taeniolite, sodium or lithium hectorite, etc.).

These water-swellable minerals have film-forming and drying properties, so they have the ability to completely bind organic flame-resistant fibers, reducing the g of the sheet.
Contributes to improving the back surface and shape retention when exposed to high temperatures.

The blending ratio of the organic flame-resistant fiber according to the present invention and the hydration-swellable mineral is appropriately determined depending on the intended use of the 4-thermal sheet, but it should be noted that the organic flame-resistant fiber 1001 fat part has a water-swelling mica group of 1 to 100). It is desirable to use it at a ratio of 1.

Other additives that may be used as necessary include:
Synthetic fibers such as lulose fibers, polyamides, polyesters, polyolefins, anionic yarn polymers (e.g. sodium polyacrylic).

Salts of partially hydrolyzed products such as polyacrylamide.

salts of maleic catalyzed copolymers), cationic thread polymers (
Examples: Partial hydrolyzate of polyacrylamide, etc.), nonionic polymers (-1 = polyacrylamide, polyvinyl alcohol, polyethylene oxide, etc.), etc.
Laughing, stringing, synthesis, 1 min i #shuoking 1, or traction-based natural polymers such as egg white, yellow mallow, and okra sara no kekkei, as well as water bathable urea resin, melamine resin, cationized starch, polyamide polyamine. Epichlorohydrin resin, polyimine resin, water bath acrylic resin, methylcellulose.

Ethylcellulose, hydroxyethylcellose.

Paper strength agents such as carboxymethyl cellulose, other maleic acid-based neutral sootening agents, rosin thread soothing agents, petroleum-based sizing agents, and 1-molecule resin emulsions.

Rubber latex etc. are used. However, it is desirable that these organic substances be added in an amount of 3% by weight or less, preferably 20% by weight or less, based on the total weight of the flame-resistant fibers and the water-use swelling compound. If it exceeds 30% by weight, the heat resistance as a heat-resistant sheet will be insufficient and it will not be suitable. Furthermore, other additives include fluorine thread-resistant T-all and mold release agents, silicone thread-resistant water and mold release agents, silane coupling agents, sulfuric acid binders, and aluminum 114 soda.

Sodium polyphosphate, ammonium polyphosphate, etc. may be added as necessary.

The heat-resistant sheet of the present invention comprises organic flame-resistant fibers and water-swellable minerals.
Furthermore, after dispersing other additives in water as necessary, the paper is formed into a sheet by a wet paper-making method or a method similar thereto.

A wet paper making method or a similar method is, for example, an aqueous dispersion applied on a filter medium such as a circular filter mesh, a square filter mesh, a filter cloth, or a filter plate. It is a general term for the method of forming a sheet-like material by pouring it into a sheet with a thickness of 100 ml, or by sandwiching it between these filtration media, and then filtering it by natural filtration or vacuum filtration. .

The sheet-like material obtained in this manner undergoes a drying process such as P-running, medium removal, drying, and peeling after drying to become a sheet. As a method for continuously forming these into sheets, there are known wet paper machines such as the elongated one-circle mesh type, the one-circle net pongee former set, and the #4 diagonal wire type.

The granite obtained in this way can be further processed with sonic waves or coated, embossing, etc.
It can be corrugated with a corrugator, laminated with other mats, or cut to an appropriate size, folded, bent, or pasted to perform secondary uO processing.

It has excellent hardness and low surface hardness, and its uses include heat-resistant punching materials, roll materials, brake friction materials, heat-resistant coating materials for rolls, welding spatter, and protective sheets.

It can be used for heat shielding sheets, heat insulating sheets, etc., but is not limited to these.

Example 1 Flame-resistant fiber (Pyromex manufactured by Toho Rayon: #Waicho 63
+11) To 100 parts by weight dispersed in water, 10 parts by weight of indium montmorillonite (NIVIA F manufactured by Kunimine Industries), which is a kind of water-swellable bentonite mineral, was swollen in water and mixed. Furthermore, 3 parts by weight of polyamide polyamine epichlorohydrin resin and then anionic polyacrylamide resin were added and mixed with 21 parts of Ibe, and 'rap' was added.
After the entire sheet was formed using a pi rectangular sheet machine, it was dried using a cylinder dryer to obtain a sheet having a thickness of RL and 5 mm with good flexibility. The sheet thus obtained and
After further heating at 400° C. for 30 minutes, the strength was measured and the results are shown in Table 1. This result shows that the heat-resistant sheet of the present invention has excellent heat resistance and is highly practical.

Example 2 IT&Fiber (Toho Rayon Pyromex: Fiber length 9
m) 1011 M g part dispersed in water,
A type of hydration-swellable mica mineral;
One part (20 weight) of Japanese squid was moistened with water and mixed. 51 parts of cationized starch was dissolved in 80°C hot water and stirred to form a Tappi Millumin square sheet machining product.After that, it was dried in a cylinder dryer and dried with a cylinder dryer. 3J, flexible notebook? Obtained.

The strength, etc. of the sheet thus obtained and the sheet ignited in the same manner as in Example 1 were measured, and the results are shown in Table 1. From this result, it can be seen that the obtained sheet is highly practical as a heat-resistant sort.

Example 3 Flame-resistant fiber (Toho Rayon Pyromex: fiber length 6i
m) 100 parts by weight of colloidal bentonite 3, which is a type of water-swellable bentonite mineral, is dispersed in water.
0 parts by weight was swollen in water and mixed.

6 parts of polyamide polyamine epichlorohydrin resin and 31 parts of carboxymethyl cellulose were added to the mixture, stirred and formed into a sheet using a 'J'appi square sheet machine, dried with a cylinder dryer and buried.
, 15 sheets were obtained. The strength, etc. of the thus obtained sheet and the sort that had been ignited in the same manner as in Example 1 were measured, and the results are shown in Table 1. From this result, the obtained sheet is highly practical as a heat-resistant sheet and has a soft texture.

Comparative Examples 1 to 3 Sheets '1 were prepared using exactly the same formulation as in Examples 1 to 3, except that the water-use swelling minerals were omitted.

Table 1 shows the results of measuring the strength of this sheet, which was ignited in the same manner as in Example 1. As can be seen from these results, the strength of nonahydrated specimens without hydrating minerals was significantly reduced by ignition.

It can also be seen that the strength before ignition treatment is lower than that of the corresponding examples.

Claims (2)

[Claims] (1) A heat-resistant sheet characterized by containing at least organic flame-resistant fibers and water-swellable minerals. (2) Claims (1) characterized in that at least organic flame-resistant fibers and water-swellable minerals are dispersed in water and formed into a sheet-like product by a wet papermaking method or a method similar thereto.
) The method for manufacturing the heat-resistant sheet described in item 2.