JPH0551550B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention is directed to gypsum reinforced with mica.
Regarding the manufacturing method of the hardened slag, more specifically, it does not contain asbestos, has non-combustibility, fire resistance, and dimensional stability,
This invention relates to a method for producing hardened gypsum and slag with excellent flexibility and bendability. [Prior art] Fiber-reinforced plaster-based hardened materials have been developed as interior and exterior materials for buildings, and applications have been published (Japanese Patent Publication No. 55
-46985). The manufacturing method for this hardened gypsum/slag body is as follows:
The main ingredients are dihydrate gypsum and crushed blast furnace slag, and an alkali salt substance is added as a stimulant for the blast furnace slag.
Furthermore, aluminum sulfate and its compounds are added as a reaction accelerator, and asbestos, glass fiber, carbon fiber, pulp, synthetic fiber, etc. are added and mixed as reinforcing fibers, and the mixture is processed by paper making, extrusion, molding, etc. It is manufactured. Materials produced by this method have high strength, quick hardening, water resistance, weather resistance, and excellent workability, but on the other hand, they have the drawback of being hard and brittle. In order to solve such problems, the inventor of the present invention, in Japanese Patent Application No. 60-295342 and Japanese Patent Application No. 61-162100, developed fiber-reinforced plaster with high flexibility. A method for producing a cured product was provided. The gist of this is that in conventional fiber-reinforced gypsum-based hardened products, part of the main raw material, dihydrate gypsum, is replaced with calcined gypsum, and a setting retardant is added. be. However, existing reinforcing fibers for interior and exterior materials for buildings are mostly non-combustible inorganic interior and exterior materials that use asbestos, but this asbestos has recently been said to be a carcinogen, and it has become a problem in the working environment of manufacturing plants. In addition to the regulations of
Due to restrictions on its use in building materials, it is no longer possible to use asbestos-free materials for ships unless they contain asbestos. Under these circumstances, glass fiber, carbon fiber,
Research and development of other organic synthetic fibers is progressing, but these fibers are not only expensive but also lack long-term material stability, and are not widely used due to the adaptability of existing equipment. Recently, some asbestos has been replaced with a mixture of organic fibers and mica, which is said to be effective in reducing asbestos as a reinforcing material for cement-based building materials. is something that does not exist yet. Also,
In the method of manufacturing cement-based building materials by replacing a portion of asbestos with a mixture of organic fibers and mica, even if laminates are manufactured using the papermaking method, the interlaminar strength is low and there is a phenomenon of delamination between the layers. ,
It was unsuitable as a building material. [Problems to be Solved by the Invention] The present inventor has developed a needle-shaped crystal produced by a paper-making method using calcined plaster and slag as the main raw materials for a matrix, and mixing organic and inorganic fibers and mica. We have developed a newly developed hardened material composed of gypsum dihydrate, ettringite, and calcium silicate gel. This is a material for interior and exterior use that is soft and flexible without containing asbestos, and is reinforced with mica. The purpose is to provide In addition, the present invention creates a gypsum/slag hardened body by a papermaking method,
The aim is to provide materials suitable for building materials that do not contain asbestos. Furthermore, it is an object of the present invention to provide a method for easily producing a hardened gypsum/slag material with good flexibility and workability using mica and glass fibers, steel fibers, or organic fibers as reinforcing materials. do. [Means for Solving the Problems] The present invention involves mixing 2 to 8 parts by weight of calcined plaster and 8 to 2 parts by weight of pulverized blast furnace slag, and adding 2 to 10% by weight of mica, glass fiber, Steel fiber, organic fiber or a combination of two or more thereof 4-10% by weight, setting retarder 0.1-1.0% by weight, flocculant 10-10%
100ppm, aluminum sulfate and its compounds 0.1~
This is a method for producing a hardened gypsum/slag body, which is characterized by mixing 5% by weight of an alkali salt substance and 0.1 to 5% by weight of an alkali salt substance with water to prepare a floc-like raw material slurry, and molding this raw material slurry by a papermaking method. [Function] According to the present invention, plaster and slag are used as a matrix, inorganic fibers and organic fibers excluding mica and asbestos are used as reinforcing materials, and water is added to this.
Further, a set retardant and a flocculant are added and mixed to create a floc-like slurry, and the slurry is molded by a papermaking method.In the hardened gypsum/slag material, the matrix is ettringite and calcium silicate hydrate. Both of the dihydrate gypsum produced from calcined gypsum are acicular crystals, and by growing these crystals larger, the bending strength of the hardened gypsum/slag product was increased, and the amount of deflection was also increased. According to the present invention, the structure of the material manufactured as a hardened gypsum/slag material is such that the hardened material from calcined plaster and slag is used as a matrix, and inorganic and organic fibers excluding mica and asbestos are used as reinforcing materials. Water is added to the mixture, and a setting retardant and a flocculant are added and mixed to form a floc-like slurry, and this slurry is formed by a papermaking method. This molded body is a hardened body composed of acicular crystal dihydrate, ettringite, and calcium silicate gel. Through the above manufacturing method, a method for manufacturing a building material that does not contain asbestos, is nonflammable, flexible, and flexible has been established. As the main raw materials, 2 to 8 parts by weight of calcined plaster and 8 to 2 parts by weight of pulverized blast furnace slag are mixed to form a matrix, and this powdery mixture matrix is 100% by weight.
2 to 10% by weight of mica, 4 to 10% by weight of glass fiber, steel fiber, organic fiber or a combination of two or more thereof, 0.1 to 1.0% by weight of setting retarder, 10 to 100ppm of flocculant, aluminum sulfate and its 0.1 to 5% by weight of the compound and 0.1 to 5% by weight of the alkali salt substance are mixed with water to prepare a floc-like raw material slurry, and this raw material slurry is shaped by a papermaking method. That is, the matrix consists of calcined plaster and ground blast furnace slag. To this, 2 to 10% by weight of mica is added. If it is less than 2% by weight, no effect on physical properties is observed, and if it is more than 10% by weight, no further effect of improving physical properties is observed.
The reason why the addition weight percentage of glass fiber etc. was set to 4 to 10 weight percent is that if it is less than 4 weight percent, no improvement in physical properties such as strength is observed, and if it is more than 10 weight percent, there is a significant increase in physical properties. It was something I didn't have. Also,
The same thing can be seen with respect to the limited range of each additive, which is limited to the above range. The matrix raw material powder mixture is put into a wet mixing tank, and glass fiber, carbon fiber, steel fiber, pulp fiber, aramid fiber, vinylon fiber, etc.
Two or more types of fibers are selected from acrylic fibers, polypropylene fibers, nylon fibers, natural vegetable fibers, etc., and added to the powder mixture in an amount of 2 to 10% by weight, preferably 4 to 8% by weight, and mica has a particle size. Maximum 3mm~
It is crushed mica with a particle size range of at least 0.1mm,
2 to 10% by weight, preferably 4 to 8% by weight, one or more selected from alkali citrate, peptone, gelatin, and amino acid derivatives as a setting retarder for plaster, 0.1 to 1.0% by weight , preferably,
Add 0.3-0.6% by weight. Further, as a reaction accelerator between slag and plaster, one or more selected from aluminum sulfate and its compounds, such as aluminum sulfate, anhydrous aluminum sulfate, sodium alum, and potassium alum, preferably 0.1 to 5% by weight. is added in an amount of 0.5 to 2.0% by weight, and one selected from among alkaline salt substances such as sodium sulfate, potassium sulfate, caustic soda, caustic potash, and slaked lime as a stimulant for slag, preferably 0.1 to 5% by weight. After adding 0.5 to 2.0% by weight and thoroughly mixing, select one type of flocculant from among polyethylene oxide polymers, polyacrylic polymers, acrylamide/acrylate polymers, 10~100ppm, preferably 25~
Add 50ppm and mix to create a flocculent slurry. The flocculant is added to prevent fine powder from flowing out and to form a flocculent slurry during the papermaking process. Next, the slurry is continuously transported by a paper machine and laminated to a desired thickness to produce a green body. The resulting form is cured naturally or by moist heat curing. After curing, the molded body is dried and made into a product.
The hardened gypsum/slag body of the present invention is a hardened body composed of mica as a reinforcing material, acicular crystal dihydrate gypsum, ettringite, and calcium silicate gel in the matrix, and has soft and flexible inside and outside. It is suitable for use as a non-combustible building material. Noncombustible interior and exterior building materials are typified by cement and asbestos products, and asbestos has been manufactured by various methods because of its good compatibility with cement.
However, as mentioned above, this asbestos is becoming unusable due to pollution regulations. Various fibers have been proposed as alternative fibers with good compatibility, but no method has been found to efficiently produce products that are made of noncombustible materials and have good compatibility with the matrix and reinforcing fibers. According to the present invention, an asbestos-free noncombustible fireproof material was obtained as a flexible noncombustible material using a hardened gypsum/slag matrix. Generally, when manufacturing cement-based or calcium silicate-based products that do not contain asbestos using the papermaking method, organic fibers, especially pulp fibers, are added at least several percent by weight to prevent the powdery matrix from flowing out. Paper is made by adding and mixing. Since this organic fiber is a flammable substance, it does not meet the nonflammability test for building materials stipulated by the Building Standards Act, and if it is to meet this requirement, the content must be extremely reduced. Therefore, papermaking becomes difficult. However, the gypsum/slag hardened body of the present invention,
Even if 5% by weight or more of these organic fibers are added and mixed, the nonflammability test can be met. This is because in the presence of mica, the organic fibers become intertwined with needle-like crystals of dihydrate gypsum and ettringite, and are coated with calcium silicate hydrate gel, and this hydrate contains a large amount of crystal water. Because of this, it does not burn and exhibits the same performance as a reinforced structure made of asbestos fibers. Next, a flocculant, which is one of the conditions of the present invention, is added, and the action of the addition causes the mixed matrix and fibers to form a floc consisting of fine particles. This prevents solids from flowing out of the system during papermaking, improves papermaking efficiency, and further increases the strength of the formed intermediate product, that is, the interlaminar strength. In addition, the two types of needle-shaped crystals of dihydrate and ettringite in the matrix surrounding mica and organic fibers are intertwined with each other, and the surroundings are further bonded by calcium silicate hydrate, so it is highly flexible. Provides water resistance and maintains high strength. The addition of mica is said to have effective reinforcing properties in the coexistence of asbestos and pulp fibers in cement systems and calcium silicate systems, but actual operational data shows that mica does not have the adsorption function of matrix like asbestos fibers. It's impossible. However, in the hardened body of the present invention using gypsum/slag as a matrix,
Mica crystals, dihydrate gypsum and ettringite crystals are intertwined with each other to form a special integrated structure, providing a cured body that is flexible and pliable and can maintain high strength. The hardened gypsum/slag body of the present invention is a material that has flexibility, flexibility, and can maintain strength.
It is suitable for interior and exterior building materials and building components, and even without asbestos fibers, it retains the high strength of conventional products, has excellent water resistance and weather resistance, and has excellent bending strength and bending workability. It is something that gives characteristics. Therefore, the gypsum/slag hardened body obtained by the present invention meets social needs and satisfies the demands of consumers. Furthermore, the gypsum/slag hardened body of the present invention is
It has excellent properties that allow it to be slightly moistened and flexed. In addition, the method for manufacturing the gypsum/slag hardened body of the present invention is as follows:
It provides an inexpensive way to produce a flexible, non-combustible material that retains its strength, expanding the range of industrial building materials available. Next, the method for producing a hardened gypsum/slag body according to the present invention will be explained using specific examples, but the present invention is not limited to the following examples. [Example] As a matrix raw material, calcined plaster and pulverized blast furnace slag were mixed in the proportions shown in the table below, this mixture was put into a wet mixing tank, and the types of fibers and mica shown in the table were used as auxiliary raw materials. In addition, as additives, setting retarders, flocculants, aluminum sulfate and its compounds, and alkali salt substances are added in the types and amounts shown in the table, and approximately 5
A floc-like raw material slurry was prepared by adding twice the amount of water, and at this time also adding about 30 ppm of an acrylamide/acrylate polymer, and this raw material slurry was molded by a papermaking method. The formed raw boards were cured under moist heat at 50℃ for 48 hours.
Cured at room temperature for 3 weeks. Fresh boards that have been cured
Various tests were conducted on the dried material in a dryer at 100°C. As shown in the table, the molded, cured, and prepared cured product was measured for its bending strength, deflection, bulk specific gravity, length change rate, as well as its physical properties upon water absorption, bending strength, deflection, etc. Examples numbered 5 to 9 in Table 1 are comparative examples for the hardened gypsum/slag products of the present invention, and even those with no added asbestos have almost the same physical properties such as bending strength and deflection as those containing asbestos. It is clear that something with this was created.

[Table] [Effects of the Invention] The method for producing a hardened gypsum/slag material of the present invention does not use asbestos as a reinforcing material, and instead contains acicular crystals of dihydrate gypsum and ettringite in the matrix around mica, and fibers. We created a hardened material by intertwining them and surrounding them with calcium silicate hydrate. Firstly, we created a hardened product that had the same high strength as conventional products without asbestos, and was flexible and flexible. We were able to provide a material with a new composition that is suitable for certain building materials and interior and exterior materials.Secondly, we were able to provide a method for producing a hardened material that uses gypsum/slag as a matrix without asbestos reinforcement and does not reduce interlaminar strength. , Thirdly, it is possible to provide a cured body of a non-combustible material that does not contain harmful asbestos and has bending strength, flexibility, flexibility, and bendability. Fourthly, it is possible to bend the molded body by slightly moistening it. Fifthly, we have been able to provide a hardened gypsum/slag material with excellent properties that allow for
Technical effects such as being able to provide a method for producing hardened slag bodies at low cost were obtained.

Claims (1)

[Claims] 1 2 to 8 parts by weight of calcined plaster and 8 parts of crushed blast furnace slag
~2 parts by weight of mica and 2 parts by weight of mica to the mixture.
-10% by weight, 4-10% by weight of glass fiber, steel fiber, organic fiber or a combination of two or more thereof, 0.1-1.0% by weight of setting retarder, 10-100ppm of flocculant, 0.1-5% by weight of aluminum sulfate and its compounds. ,
Mixing 0.1 to 5% by weight of an alkaline salt substance with water,
A method for producing a hardened gypsum/slag body, which is characterized by creating a floc-like raw material slurry and molding this raw material slurry by a papermaking method.