KR100455472B1 - Calcium silicate board and method of manufacturing same - Google Patents

Abstract

The present invention provides a method for producing a calcium silicate plate having a volume specific gravity of about 0.5 to 0.8 to reduce the volume specific gravity of the plate and increase the matrix strength without lowering the productivity, and also to produce the calcium silicate plate by the above method. It's about doing. The method for producing calcium silicate plate according to the present invention comprises 5 to 30 wt% of calcium silicate hydrate slurry as a solid component, 17 to 50 wt% of calcite raw material, 13 to 45 wt% of siliceous raw material, and 2 to 8 wt% Slurry raw material containing a fibrous raw material and 5 to 40 wt% of an inorganic filler is molded by a conventional process, and the molded body is hydrothermally reacted in a pressure vessel.

Description

Calcium silicate plate and its manufacturing method {CALCIUM SILICATE BOARD AND METHOD OF MANUFACTURING SAME}

Conventionally, calcium silicate plates have been widely used as building materials, and in particular, they are widely used as inner materials because of their lightness, excellent processability and spatial stability, and also incombustibility.

Calcium silicate plates for building materials are formed using a molding process such as a press mold process or a Hatschek sheet metal machining process, which is a single layer mold process, and is also manufactured by the following method. That is, the molded body is molded from inorganic fillers such as lime raw materials, siliceous raw materials, reinforcing fibers and lightweight aggregates, and is then generally cured by saturated steam in a pressure vessel. In general, the volume specific gravity of the calcium silicate plate is in the range of 0.7 to 1.2.

Since calcium silicate plates are used for interior materials such as ceiling materials and wall materials, hard boards are preferred, but according to the above method, it is necessary to mix a considerable amount of lightweight aggregate so that the specific gravity of the volume is 0.5 to 0.8, and consequently the specific strength of the plates. Results in a decrease.

In particular, when a lightweight calcium silicate plate having a volume specific gravity of 1.0 or less is produced by a sun sheet mechanical process, the following problems sometimes occur. That is, due to the low strength of the molded body and the high water content before the hydrothermal reaction, excess water thermally expands or increases the vapor pressure during the hydrothermal reaction, resulting in problems of delamination or fracture.

In some methods, in order to solve the above problem, the molded body is compressed after molding and then hydrothermally reacted or tensioned by a turnbuckle during the hydrothermal reaction. However, according to the above method, there is a problem of increasing the specific gravity of the volume and requiring more labor in manufacturing.

Incidentally, an extra water removal method was disclosed in Japanese Patent Laid-Open No. 6-287083, but was not generally used because a specific pressure vessel or steam heater was required.

In addition, conventionally, slurry stocks containing amorphous lime stock and amorphous silicic acid stocks are heated at normal pressure during gelation to make hard plates. However, according to the above method, the strength of the plate is absolutely reduced, and the raw material is so soft that the problem of being easily shaved during polishing occurs. Thus, the problem arises that the cellulose fiber is extremely fluffed to such an extent that the surface smoothness is impaired when the plate is used after coating.

In addition, a method in which calcium silicate plates showing good strength can be obtained by adding xontlite, which is one kind of calcium silicate hydrate, or crystalline calcium slurry, has been disclosed in Japanese Patent Laid-Open Nos. 52-105926 and 52-135330. Since the productivity decreases because of the above method, an improvement is required in view of the manufacturing cost.

Incidentally, in Japanese Patent Laid-Open Nos. 5-213657 and 7-41354, the inventors of the present invention have already disclosed a method of adding a gelatinized slurry and a crystalline calcium silicate hydrate slurry composed of a lime raw material and an amorphous silicic acid raw material. However, in the case of plates laminated by a hex thin sheet machine process, the problem of delamination and fracture occurs even in the above method of adding a gel.

In addition, Japanese Patent Publication 58-30259 discloses a method for producing a calcium silicate molded article having the following characteristics. The siliceous raw material and the calcareous raw material are solid component raw materials and are dispersed in water having a weight of 15 times or more than the weight of these raw materials, and the obtained mixture is heated and reacted at 130 ° C. or higher under pressure, and the silicic acid composed of CSH or tobermorite A water-soluble slurry having a sedimentation volume of 15 cm 3 / g or more containing calcium is formed, asbestos is added to the water-soluble slurry, further dehydrated, and the calcium silicate hydrate is transformed into steam curing under pressure. However, the calcium silicate molded article obtained by the above method is used as a heat insulating material or a heat insulating material, and according to the embodiment of the above publication, the volume specific gravity is as small as 0.1 to 0.2 g / cm 3. The calcium silicate molded body cannot be used for calcium silicate plates used for building materials.

Accordingly, an object of the present invention is to provide a method for producing a calcium silicate plate having a volume specific gravity of about 0.5 to 0.8 in order to obtain a volume specific gravity reduction effect and a synergistic effect of matrix strength without lowering productivity, and also produced by the above method. To provide a calcium carbonate plate.

Another object of the present invention is that the strength of the molded body (raw plate) is improved by using a raw material having good reactivity with the siliceous raw material and by primary curing before the hydrothermal reaction. It is to provide a method for producing a calcium silicate plate having a volume specific gravity of 1.0 or less to solve the problem.

In addition, in a method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less by using a gel consisting of a gelling raw material for gelling and a siliceous raw material for gelling, another object of the present invention is to provide a method for preparing a calcium silicate plate before hydrothermal reaction in order to avoid peeling and breaking during hydrothermal reaction. The present invention provides a method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less and an excellent interlaminar peeling strength in which the above-mentioned problem is solved by increasing the strength of a molded product by increasing the curing.

Means to solve the problem

Slurry consisting of 5 to 30 wt% calcium silicate hydrate slurry, 17 to 50 wt% calcareous raw material, 13 to 45 wt% siliceous raw material, 2 to 8 wt% fibrous raw material and 5 to 40 wt% inorganic filler as solid components A method for producing a calcium silicate plate, which comprises forming a raw material by a conventional process and hydrothermally reacting a molded product obtained in a pressure vessel (hereinafter referred to as first invention).

In addition, the present invention relates to a calcium silicate plate having a volume specific gravity of 0.5 to 0.8 and a wear index of 0.3 to 2 produced by the above method (hereinafter referred to as second invention).

The wear index is obtained by a test of 1,000 cycles at a load of 1,000 g using a wear ring of CS-10, and is also calculated by the formula of wear index = weight loss (g) / volume specific gravity. Evaluated according to standard KIS04.

In addition, the present invention defines a slurry raw material comprising 17 to 50 wt% of a calcined raw material, 15 to 45 wt% of a siliceous raw material, 2 to 8 wt% of a fibrous raw material and 5 to 40 wt% of an inorganic filler as a solid component. A method for producing a lightweight calcium silicate plate (hereinafter referred to as calcium silicate plate) comprising the steps of forming into a form and hydrothermally reacting a formed article obtained in a pressure vessel, wherein the silicate raw material is not less than 1 m 2 / g. 2 to 20 wt% of at least one amorphous silicic acid raw material and a silicate raw material each having a specific surface area are used, and before the hydrothermal reaction, the molded body is first cured under the conditions of (cure temperature-15) x curing time ≥ 120 ° C. It relates to a manufacturing method (hereinafter referred to as third invention).

Incidentally, the present invention is a solid component of 5 to 35 wt% lime material, 5 to 40 wt% siliceous material, 2 to 8 wt% fibrous material and 5 to 40 wt% inorganic filler and 2 to 20 wt% 0.70 comprising forming a slurry raw material in a lamination by a hot-plate lamination process of a slurry raw material comprising a gel obtained from a gelling calcined raw material and a 3 to 25 wt% gelling siliceous raw material, and a hydrothermal reaction of a molded product obtained in a pressure vessel. In the method for producing a calcium silicate plate having a volume specific gravity below, 2 to 20 wt% of one or more amorphous silicic acid raw materials and silicate raw materials each having a specific surface area of 1 m 2 / g or more is used as a part of the siliceous raw material, and before hydrothermal reaction The molded body was first cured under the conditions of (curing temperature -15) x curing time ≥ 120 deg. C. hours, and the bending strength of the molded body was 7 / ㎠ or more or a method for producing becomes equal to or greater than 1.3 times the flexural strength before the primary curing (hereinafter referred to as a fourth invention).

In addition, the present invention is a solid component of 5 to 35 wt% lime material, 5 to 40 wt% siliceous material, 2 to 8 wt% fibrous material and 5 to 40 wt% inorganic filler and 2 to 20 wt% gelling Forming a slurry raw material by laminating a slurry raw material comprising a molten lime raw material and a gel obtained from a 3 to 25 wt% silicate raw material for gelling by a hot-plate lamination process; and hydrothermally reacting a molded product obtained in a pressure vessel. In the method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less, 2 to 20 wt% of one or more amorphous silicic acid raw materials and silicate raw materials each having a specific surface area of 1 m 2 / g or more is used as a part of the siliceous raw material, and the slurry The raw material comprises up to 20 wt% of a curing agent selected from the group consisting of Portland cement, alumina cement, and granular furnace slag, and Before the hydrothermal reaction, the molded body was first cured under the conditions of (curing temperature -10) x curing time ≥ 120 ° C.times, and the bending strength of the molded body in the wet state was 7 kg / cm 2 or more, or 1.3 than the bending strength before the primary curing. It relates to a manufacturing method which is twice or more (hereinafter referred to as the fifth invention).

In addition, the present invention provides 5 to 35 wt% of calcareous raw materials, 5 to 40 wt% of siliceous raw materials, 2 to 8 wt% of fibrous raw materials and 5 to 40 wt% of inorganic fillers and 2 to 20 wt% of gelling as a solid component. Forming a slurry raw material by laminating a slurry raw material comprising a molten lime raw material and a gel obtained from a 3 to 25 wt% silicate raw material for gelling by a hot-plate lamination process; and hydrothermally reacting a molded product obtained in a pressure vessel. In the method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less, the slurry raw material includes 20 wt% or less of a curing agent selected from the group consisting of Portland cement, alumina cement, and granular furnace slag, and the molded body before hydrothermal reaction. (Curing temperature -10) x bending strength of the molded body in the wet state in the first curing under conditions of curing time ≥ 120 ℃ The 7 ㎏ / ㎠ or more or a method for producing becomes equal to or greater than 1.3 times the flexural strength before the primary curing (hereinafter referred to as the sixth invention).

In addition, the present invention relates to a calcium silicate plate having a volume specific gravity of 0.07 or less produced by the above method, wherein the calcium silicate plate has an interlaminar peel strength of 3% or more of the flexural strength (hereinafter referred to as the seventh invention). ).

Embodiment of the invention

In the method for producing calcium silicate plate according to the first invention of the present invention, a calcium silicate hydrate slurry having a sedimentation volume of 5 to 14 ml / g is used as the calcium silicate hydrate slurry, which is composed essentially of an amorphous raw material, wherein the slurry is Slurry composed of lime and crystalline silicic acid raw materials having a Ca / (Si + Al) molar ratio of 0.3 to 0.8 and water obtained by hydrothermal reaction under conditions in which the reaction rate of crystalline silicic acid raw materials is in the range of 40 to 80% at saturated vapor pressure. It is characterized by.

The calcium silicate hydrate slurry composed essentially of the amorphous raw material according to the first invention of the present invention is composed of a crystalline silica raw material and a crystalline silica raw material having a molar ratio of Ca / (Si + Al) of 0.3 to 0.8. The hydrothermal reaction proceeds at a ratio of water of 10 to 20, at a temperature of 120 to 200 ° C, at a reaction rate of 40 to 80% of the crystalline silica raw material, and for 3 to 8 hours at saturated vapor pressure.

Calcium hydroxide and quicklime are examples of calcareous raw materials. Silica sand and sintered diatomaceous earth are examples of crystalline silicic acid raw materials. When the Ca / (Si + Al) molar ratio of the aforementioned slurry is less than 0.3, since the amount of calcium silicate hydrate produced is small, the specific gravity reduction effect and the matrix strength increasing effect are undesirably reduced. On the other hand, if the molar ratio exceeds 0.8, an increase in sedimentation volume results in undesirable consequences of increased water content and lower productivity.

In addition, when the reaction rate of the crystalline silicic acid raw material is less than 40%, since the production amount of calcium silicate hydrate is small, the specific gravity reduction effect and the matrix strength increase effect are undesirably reduced. On the other hand, if the reaction rate exceeds 80%, due to the increase in sedimentation volume, an undesirable result of an increase in water content and a decrease in productivity is caused. The crystal phase of the crystalline silicic acid raw material is quartz or cristobalite, and the reaction rate can also be evaluated by powder X-ray diffraction method according to the standard addition method. When the crystal phases are quartz and cristoberrite, respectively, the peaks of (10.1) and (101) are used, respectively.

The calcium silicate hydrate slurry consisting essentially of the amorphous raw material produced by the process has a settling volume in the range of 5 to 14 ml / g. When the calcium silicate hydrate slurry is used as a raw material of the calcium silicate plate, the specific gravity reduction effect and the increase in the matrix strength are achieved without a decrease in productivity. The sedimentation volume is obtained by adding 7 g of calcium silicate hydrate slurry consisting essentially of amorphous raw material as a solid component in a 200 ml measuring cylinder, diluted with 200 ml water and left for 3 hours. The volume is measured by this method.

Moreover, the basic composition of the slurry raw material used for the manufacturing method of the calcium silicate plate which concerns on the 1st invention of this invention is as follows. That is, the basic composition of the slurry raw material is 5 to 30 wt% calcium silicate hydrate slurry, 17 to 50 wt% lime material, 13 to 45 wt% siliceous material, 2 to 8 wt% fibrous, which constitutes essentially amorphous raw material as a solid component. Raw materials and 5 to 40 wt% inorganic fillers. After molding, the slurry raw material is hydrothermally reacted in a pressure vessel, and is also formed into a calcium silicate plate through a conventional process. The hydrothermal reaction proceeds in a pressure vessel under saturated water steam at a temperature of 150 to 200 ° C., preferably at 170 to 190 ° C. for 5 to 20 hours, more preferably at 8 to 12 hours.

When the content of the calcium silicate hydrate slurry consisting essentially of amorphous raw material is less than 5 wt% as a solid component, the specific gravity reduction effect is small, while if the content exceeds 30 wt%, the volume specific gravity decreases to give the strength of the calcium silicate plate. Is not preferred because is insufficient as a building material.

For example, calcium hydroxide and quicklime can be used as a calcareous raw material. The calcareous raw material in the range of less than 17 wt% or greater than 50 wt% causes problems such as a decrease in flexural strength and an increase in the rate of dimensional change due to water absorption.

In addition, silica sand, fly ash, diatomaceous earth, silicon dust, white carbon, zeolite and montmorillonite are examples of siliceous raw materials. Silicate raw materials in the range of less than 13 wt% or greater than 45 wt% cause problems such as a decrease in flexural strength and an increase in the rate of dimensional change due to water absorption.

In addition, cellulose fibers, polypropylene, vinylon, glass fibers and carbon fibers are examples of fibrous raw materials. Fibrous raw materials with a content of less than 2 wt% are not preferred because of their reduced flexural strength. On the other hand, fibrous raw materials with contents greater than 8 wt% cause non-combustible losses. Incidentally, when polypropylene, vinylon, glass fiber or carbon fiber is used, the preferred content thereof is therefore 5 wt% or less.

In addition, pearlite, wallastonite, mica, talc, calcium carbonate and gypsum are examples of inorganic fillers. Inorganic fillers with a content of less than 5 wt% are undesirable because they cause an increase in the rate of dimensional change due to moisture absorption. Inorganic fillers with a content of more than 40 wt% are undesirable because they reduce the flexural strength.

Incidentally, as the molding method, a conventional molding method such as a hemp thin sheet metal process, a mold press process, and a single layer molding method can be used.

The calcium silicate plate according to the second invention of the present invention has excellent matrix strength and good wear resistance despite the fact that the volume specific gravity thereof is in the range of 0.5 to 0.8.

The basic composition of the slurry raw material used in the calcium silicate plate production method according to the third invention of the present invention is a conventional composition as follows. That is, the composition is a solid component, such as 17 to 50 wt% lime raw material, 15 to 45 wt% siliceous raw material, 2 to 8 wt% fibrous raw material and 5 to 40 wt% inorganic filler.

The same raw material as described above may be used as a calcareous raw material. Lime stocks with a content of less than 17 wt% or greater than 50 wt% are undesirable because they lead to reduced flexural strength and increased rate of dimensional change due to water absorption.

Incidentally, silica sand, fray ash and the like may be used as the siliceous raw material. Silicate raw materials whose contents are less than 15 wt% or greater than 45 wt% are undesirable because they cause a decrease in flexural strength and an increase in the rate of dimensional change due to water absorption.

In addition, the same raw material as the above may be used as the fibrous raw material. Fibrous raw materials with a content of less than 2 wt% are undesirable because of reduced flexural strength, and fibrous raw materials with a content of more than 8 wt% are undesirable because they cause non-combustible losses. Incidentally, when polypropylene, vinylon, glass fiber or carbon fiber is used, it is necessary to set the content of 5 wt% or less.

In addition, the same raw material as mentioned above can be used as the inorganic filler. Inorganic fillers with a content of less than 5 wt% are undesirable because they cause an increase in the rate of dimensional change due to moisture absorption. Inorganic fillers with a content of more than 40 wt% are undesirable because they reduce the flexural strength.

A first feature of the third invention of the present invention is that it is an amorphous silicate raw material or silicate raw material having a specific surface area of 1 m 2 / g or more used as part of the siliceous raw material of the slurry raw material having the above-described composition. The "specific surface area" is measured by the N ₂ gas absorption method. An amorphous silicic acid raw material or silicate raw material having a specific surface area of 1 m 2 / g or less is not preferable because the green sheet cannot obtain sufficient strength due to inferior reactivity before hydrothermal reaction.

In addition, the amorphous silicic acid raw material or silicate raw material content having a specific surface area of 1 m 2 / g is in the range of 2 to 20 wt%. A content of less than 2 wt% is undesirable because of low strength reproducibility, and a content of more than 20 wt% is undesirable because it leads to a decrease in productivity due to a decrease in free water properties. When a raw material having a specific surface area of 1 to 10 m 2 / g is used, the preferred content is 10 wt% or more, and a raw material having a specific surface area of 10 to 100 m 2 / g is preferably 5 wt% or more. In the case of a raw material having a specific surface area of 100 m 2 / g or more, a content of 2 wt% or more is preferable.

Examples of amorphous silicic acid raw materials having a specific surface area of 1 m 2 / g or more are diatomaceous earth, silicon powder, fray ash and white carbon. Incidentally, examples of silicate raw materials having a specific surface area of 1 m 2 / g or more include zeolite, allophane, montmorillonite, chlorite mineral and attapulgite and the like. Two or more kinds of the above raw materials may be used in combination.

The second feature of the third invention of the present invention is that the raw thin plate (molded body) does not undergo a hydrothermal reaction except that it is subjected to primary curing, and the raw thin plate is formed by forming a slurry raw material composed of the above-described raw material composition. Equally, for example, it is formed and obtained in a form defined by a hessian thin sheet machine process. Primary curing is carried out under the following conditions. That is, it proceeds under the conditions of (cure temperature-15) x curing time ≥ 120 ° C.hr. Since curing is insufficient and the raw sheet cannot obtain sufficient strength, primary curing is not preferable under the conditions of 120 ° C · hr or less. Primary curing requires a curing temperature greater than 15 ° C., and it is preferable to proceed under conditions of 240 ° C. · hr or more in a curing temperature range of 30 to 80 ° C.

After the above mentioned primary curing, the raw thin plate undergoes a conventional hydrothermal reaction and is also formed into a calcium silicate plate by a conventional process. The hydrothermal reaction can be carried out in a pressure vessel under saturated steam at a temperature of 150 to 200 ° C., and the preferred hydrothermal reaction is carried out in a pressure vessel under saturated steam for 5 to 20 hours at 170 to 190 ° C., more preferably hydrothermal. The reaction is when running in a pressure vessel under saturated steam for 8 to 12 hours.

According to the manufacturing method of the 3rd invention of this invention, a calcium silicate plate which has a volume specific gravity of 1.0 or less can be produced.

The basic composition of the slurry raw material used for the calcium silicate plate production method according to the fourth to sixth invention of the present invention is a conventional composition as follows. That is, the composition is 5 to 35 wt% calcite raw material, 5 to 40 wt% siliceous raw material, 2 to 8 wt% phosphorus raw material, 5 to 40 wt% inorganic filler, and 2 to 20 wt% gelling raw material and 3 to 3 wt% 25 wt% gel obtained from siliceous raw material for gelation. Incidentally, the aforementioned slurry raw material may include up to 20 wt% of a curing agent.

The same raw materials described above can be used as the calcareous raw materials. Lime stocks with a content of less than 5 wt% or greater than 35 wt% are undesirable because they cause a decrease in flexural strength and an increase in the rate of dimensional change due to water absorption.

Incidentally, silica sand, fray ash and the like may be used as the siliceous raw material. Silicate raw materials whose contents are less than 5 wt% or greater than 40 wt% are undesirable because they cause a decrease in flexural strength and an increase in the rate of dimensional change due to water absorption.

In addition, the same raw material as the above may be used as the fibrous raw material. Fibrous raw materials with a content of less than 2 wt% are undesirable because of reduced flexural strength, and fibrous raw materials with a content of more than 8 wt% are undesirable because they cause non-combustible losses. In other words, when polypropylene, vinylon, glass fiber or carbon fiber is used, it is necessary to set the content of 5 wt% or less.

In addition, the same raw materials described above can be used as the inorganic filler. Inorganic fillers with a content of less than 5 wt% are undesirable because they cause an increase in the rate of dimensional change due to moisture absorption. Inorganic fillers with a content of more than 40 wt% are undesirable because they reduce the flexural strength.

According to the method according to the fourth to sixth inventions of the present invention, an amorphous silicic acid raw material or a silicate raw material having a specific surface area of 1 m 2 / g or more may be formed of a siliceous raw material of a slurry raw material having the above-described composition similar to the third invention of the present invention. Used as part.

The content of amorphous silicic acid raw material or silicate raw material having a specific surface area of 1 m 2 / g or more is in the range of 2 to 20 wt%, similar to the third invention of the present invention.

The same raw material as described above may be used as an amorphous silicic acid raw material having a specific surface area of 1 m 2 / g or more.

In the method according to the fourth to sixth inventions of the present invention, the method is, for example, at 75 to 95 ° C. for 1.5 to 4 hours, 2 to 20 wt% of the calcined calcareous raw material and 3 to 25 wt% The gel obtained by gelation of the siliceous raw material for gelation is essentially used. Calcium silicate plates having a volume specific gravity of 0.7 or less can be easily obtained by using the aforementioned gel for slurry raw material to produce calcium silicate plates. None of the gelling calcined raw material and the gelling siliceous raw material is limited to the kind of specific raw material, and any conventional raw material may also be used. For example, calcium hydroxide and quicklime can be used as a calcareous raw material for gelling. Silicon powder, prey ash, white carbon, etc. may be used as the siliceous raw material for gelling.

In addition, the curing agent may be added to the slurry raw material according to the fourth to sixth inventions of the present invention. Portland cement, alumina cement and granular furnace slag may be used as hardeners to increase the flexural strength by primary curing. When using a curing agent, the content of the curing agent is 20 wt% or less, preferably in the range of 3 to 20 wt%. When the content exceeds 20 wt%, the volume specific gravity of the calcium silicate plate increases, and it is undesirably impossible to produce calcium silicate plates having a volume specific gravity of 0.70 or less. If the content is less than 3 wt%, the effect of adding the hardener is sometimes hindered.

According to the fourth to sixth inventions of the present invention, a slurry raw material of this kind is formed between layers by a hessian thin sheet mechanical process, and this slurry raw material has a gel as part of it, and has a specific surface area of 1 m 2 / g or more. It contains or does not include amorphous siliceous raw materials or silicate raw materials having, and also contains or does not contain a curing agent. The present invention is not limited to the hex sheet metal machine process, and any conventional process may be used.

A feature of the fourth to sixth inventions of the present invention is similar to that of the third invention of the present invention, except that the molded article obtained by the above method does not undergo a hydrothermal reaction except that it is subjected to primary curing. If the slurry raw material does not contain a curing agent, the primary curing proceeds under the following conditions. That is, (cure temperature-15) x curing time≥120 degreeC * hr. Since the molded body cannot obtain sufficient strength due to lack of curing, primary curing conditions of less than 120 ° C · hr are undesirable. Primary curing requires a curing temperature of 15 ° C. or higher, and preferably proceeds under conditions of 240 ° C. · hr or more at curing temperatures in the range of 30 to 80 ° C. In addition, when the slurry raw material includes a curing agent, primary curing may proceed under the following conditions. That is, it is a condition of (cure temperature-10) x curing time≥120 degreeC * hr. This is the reason why the reaction using the curing agent can proceed easily at low temperatures as compared with the lime raw material, siliceous raw material, especially amorphous silica raw material and silicate raw material. In the above case, the primary curing requires a curing temperature of 10 ° C. or more, and preferably proceeds under a condition of 240 ° C. · hr or more in a curing temperature range of 25 to 80 ° C.

By performing the above-mentioned primary curing, the bending strength of the molded body in the wet state is increased by 7 kg / cm 2 or more, and 1.3 times more than the bending strength before the primary curing.

After the above-mentioned primary curing, the molded body can undergo a conventional hydrothermal reaction and can also form a calcium silicate plate by a conventional process. The hydrothermal reaction can be carried out in a pressure vessel under saturated steam at a temperature of 150 to 200 ° C., preferably at 170 to 190 ° C. for 5 to 20 hours, more preferably 8 to 12 hours.

According to the manufacturing method according to the seventh invention of the present invention, a calcium silicate plate having a volume specific gravity of 0.70 or less is obtained, and clearly excellent interlaminar peel strength (absolutely under dry conditions) of 3% or more of flexural strength (absolutely under dry conditions). ). In this case, flexural strength was measured according to Japanese Industrial Standard A5418 using specimen 3, and a 30 × 30 mm specimen was used for the interlaminar peel test.

The present invention relates to a method for producing a calcium silicate plate and a calcium silicate plate obtained by the method.

Calcium silicate production method according to the present invention will be understood in more detail by the following description taken in conjunction with the examples and comparative examples.

Example 1 and Comparative Example 1

An embodiment of the preparation of calcium silicate hydrate slurries consisting essentially of amorphous raw materials.

A slurry consisting essentially of an amorphous raw material is obtained as follows. That is, calcium hydroxide and silica sand are mixed according to the formulation shown in Table 1. Each mixture is mixed in an amount of 13 times the amount of water, and after stirring each resultant mixture is hydrothermally reacted according to the mutual conditions indicated in Table 1. Experimental pressure cookers are used for hydrothermal reactions.

Experiment number One 2 3 4 5 6 Raw material Calcium tetrahydrate Ca / (Si + Al) molar ratio temperature (℃) time (hr) water stirring speed (m / min) 0.4 180 6 13 100 0.6 180 4 13 100 0.8 150 4 13 100 0.2 180 6 13 100 1.0 150 4 13 100 0.6 180 10 13 100 Crystalline Silicate Raw Material Reaction Rate 48 57 78 31 95 73 Sedimentation volume (ml / g) 6.4 7.1 9.0 5.8 14.5 15.8

Raw materials were prepared according to the formulations shown in Table 2. Each raw material was formed into a slurry having a solid concentration of 10%, press-molded into pieces of 30 × 30 × 0.8 cm at a press pressure of 10 kg / cm 2, and then hydrothermally reacted at 180 ° C. for 10 hours under saturated water vapor. .

Table 2 shows volume specific gravity, flexural strength (absolutely under dry conditions) and wear index.

Example Comparative Example One 2 3 4 One 2 3 4 5 Compound (wt%) Calcium Oxide Hydrate Slurry Experiment No. Content (Solid Components) 1 28 2 7 3 15 1 7 2 35 4 28 5 15 6 7 2 3 Calcium Hydroxide Wollastonite Pearlite Calcium Pulp Glass Fiber 32 24 10--5 1 28 26 20 5 10 3 1 29 28 10-10 7 1 34 33 10-10 5 1 26 23 10--5 1 35 21 10--5 1 29 28 10-10 7 1 28 26 20 5 10 3 1 41 40 10--5 1 Volumetric specific gravity bending strength (kg / ㎠) 0.55 92 1.8 0.68 115 0.43 0.63 122 1.1 0.78 118 0.32 0.48 88 2.3 0.73 104 0.27 0.61 111 1.4 0.64 118 1.2 0.82 126 0.20 productivity ○ ○ △ ○ × ○ × × ○

In Table 2, when a 1 liter slurry with a concentration of 4.2% as a solid component is placed in a Buchner funnel with a diameter of 16 cm and filtered at 50 cm Hg, the filtration rate (ml / sec) is filtered It is defined as the value of water (ml) / filtration time (seconds). Filtration speeds of 30 or more were indicated by o, 20 or more and less than 30 were indicated by △, and less than 20 by x.

Example 2 and Comparative Example 2

Calcium hydroxide, silica sand, wallastonite, pearlite, pulp, amorphous silicic acid raw materials and silicate raw materials are mixed according to the combinations shown in Table 3, and then each of the mixtures is mixed and stirred in a 12-fold amount of water.

By further adding water thereto, a slurry raw material having a solid concentration of about 3 wt% is obtained, and is formed to a sheet thickness of 6 mm by a hemp thin sheet mechanical process.

Subsequently, each synthetic raw thin plate is subjected to hydrothermal reaction for 10 hours at 180 ° C. under saturated steam after primary curing according to the conditions of temperature and time shown in Table 3.

Table 3 shows the peeling and breaking of the raw thin plate after the hydrothermal reaction, and also shows the volume specific gravity and the bending strength of the calcium silicate plate obtained under absolute dry conditions.

In Table 3, 20 m 2 / g of diatomaceous earth, 20 m 2 / g of silicon powder, 220 m 2 / g of white carbon and 6.5 m 2 / g of zeolite specific surface area were measured by the N ₂ gas absorption method. In addition, ○ indicates good productivity and × indicates poor productivity.

Example 3 and Comparative Example 3

Each raw material prepared according to the formulation shown in Table 4 is mixed and stirred in 12 times the amount of water. The gel used here is obtained by gelation of calcium hydroxide and diatomaceous earth in a weight ratio of 1: 1, and the gelation proceeds at a water ratio of 5 times, 90 DEG C and 2 hours. In the table, the gel concentration is expressed as a solid component.

By further adding water, a slurry raw material having a solid concentration of about 3 wt% is obtained, and is formed into a thin plate thickness of 6 mm by a hess thin plate mechanical process.

Subsequently, each synthetic raw thin plate is subjected to hydrothermal reaction for 10 hours at 180 ° C. under saturated steam after primary curing according to the conditions of temperature and time shown in Table 4.

Table 4 shows the bending strength of the molded body after the primary curing, and also shows the volume specific gravity after the hydrothermal reaction, the bending strength and the interlaminar peel strength measured under the absolute dry state.

In Table 4, 20 m 2 / g silicon powder, 6.5 m 2 / g zeolite and 2.0 m 2 / g diatomaceous earth specific area were measured by N ₂ gas absorption method.

effect

According to the method for producing calcium silicate according to the first invention of the present invention, a calcium silicate plate having good matrix strength and wear resistance can be produced despite the fact that the volume specific gravity is in the range of 0.5 to 0.8.

According to the method for producing a calcium silicate plate according to the third invention of the present invention, it is possible to improve the strength of a raw thin plate obtained by molding a slurry raw material into a prescribed form, whereby peeling, breaking, etc. of the raw thin plate during hydrothermal reaction can be achieved. You can prevent it.

According to the calcium silicate plate production method according to the fourth to sixth inventions of the present invention, it is possible to improve the strength of the raw thin plate obtained by molding the slurry raw material into a prescribed form. By this method, peeling, breaking, etc. of the raw thin plate during the hydrothermal reaction are prevented, and the interlayer peel strength of the calcium silicate plate having a volume specific gravity of 0.70 or less is improved.

Claims (7)

In the manufacturing method of calcium silicate plate, 5 to 30 wt% calcium silicate hydrate slurry as solid component, 17 to 50 wt% lime material, 13 to 45 wt% siliceous raw material, 2 to 8 wt% fibrous raw material and 5 to 40 wt% Molding the slurry raw material including the inorganic filler by a conventional process; Hydrothermally reacting the molded body in a pressure vessel; The calcium silicate hydrate slurry consists essentially of an amorphous raw material, and the calcium silicate hydrate slurry comprises a slurry and water consisting of a calcite raw material and a crystalline silicate raw material having a Ca / (Si + Al) molar ratio of 0.3 to 0.8 at a saturated vapor pressure. A method for producing a calcium silicate, wherein the calcium silicate hydrate slurry has a precipitate volume of 5 to 14 ml / g, obtained by hydrothermal reaction under conditions in which the reaction rate of the crystalline silicate raw material is in the range of 40 to 80%. . Calcium silicate plate produced by the method according to claim 1, wherein the calcium silicate plate has a volume specific gravity in the range of 0.5 to 0.8 and a wear index in the range of 0.3 to 2. Shaping, in a solid form, a slurry stock consisting of 17-50 wt% lime material, 15-45 wt% siliceous material, 2-8 wt% fibrous material, and 5-40 wt% inorganic filler. , And In the method for producing a lightweight calcium silicate plate comprising the step of hydrothermally reacting a molded product obtained in a pressure vessel, As a part of the siliceous raw material, 2 to 20 wt% of at least one amorphous silicic acid raw material and a silicate raw material each having a specific surface area of 1 m 2 / g or more are used, and before the hydrothermal reaction, the molded body is subjected to (curing temperature-15) x curing time ≥ A method for producing a lightweight calcium silicate, characterized in that the first curing under conditions of 120 ℃ time. 5 to 35 wt% of calcite raw material, 5 to 40 wt% of siliceous raw material, 2 to 8 wt% of fibrous raw material and 5 to 40 wt% of inorganic filler and 2 to 20 wt% of gelling raw material and 3 Shaping the slurry raw material in a lamination by using a thin sheet mechanical process, the slurry raw material consisting of a gel obtained from to 25 wt% gelling siliceous raw material, and In the method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less comprising the step of hydrothermally reacting a molded product obtained in a pressure vessel, As a part of the siliceous raw material, 2 to 20 wt% of at least one amorphous silicic acid raw material and silicate raw material each having a specific surface area of 1 m 2 / g or more is used, and the molded body is subjected to (curing temperature-15) x curing time ≥ 120 Silicate having a volume specific gravity of 0.70 or less, characterized in that the cured strength of the molded body is 7 kg / cm 2 or more or 1.3 times or more than the bending strength before the primary curing under primary curing under wet conditions. Calcium plate manufacturing method. 5 to 35 wt% of calcite raw material, 5 to 40 wt% of siliceous raw material, 2 to 8 wt% of fibrous raw material and 5 to 40 wt% of inorganic filler and 2 to 20 wt% of gelling raw material and 3 Shaping the slurry raw material in a lamination by using a thin sheet mechanical process, the slurry raw material comprising a gel obtained from to 25 wt% gelling siliceous raw material, and In the method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less comprising the step of hydrothermally reacting a molded product obtained in a pressure vessel, As a part of the siliceous raw material, 2 to 20 wt% of at least one amorphous silicic acid raw material and silicate raw material each having a specific surface area of 1 m 2 / g or more is used, and the slurry raw material is composed of Portland cement, alumina cement, and granular furnace slag. 20 wt% or less of a curing agent selected from the above, and before the hydrothermal reaction, the molded body is first cured under the conditions of (cure temperature-10) × curing time ≥ 120 ° C. A method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less, characterized in that it is not less than kg / cm 2 or 1.3 times or more than the flexural strength before primary curing. 5 to 35 wt% of calcareous raw material, 5 to 40 wt% of siliceous raw material, 2 to 8 wt% of fibrous raw material and 5 to 40 wt% of inorganic filler and 2 to 20 wt% of gelling raw material and 3 Shaping the slurry raw material in a lamination by using a thin sheet mechanical process, the slurry raw material comprising a gel obtained from to 25 wt% gelling siliceous raw material, and In the method for producing a calcium silicate plate having a volume specific gravity of 0.70 or less comprising the step of hydrothermally reacting a molded product obtained in a pressure vessel, The slurry raw material contains 20 wt% or less of a curing agent selected from the group consisting of Portland cement, alumina cement, and granular furnace slag, and the molded body is subjected to (curing temperature-10) x curing time ≥ 120 ° C · hour before hydrothermal reaction Calcium silicate plate having a volume specific gravity of 0.70 or less, characterized in that the cured strength of the molded body is 7 kg / cm 2 or more or 1.3 times or more than the flexural strength before the first curing in the wet state under primary curing. Way. Calcium silicate plate whose volume specific gravity manufactured by the method in any one of Claims 4-6 is 0.70% or less, The interlaminar peeling strength of a calcium silicate plate is 3% or more of bending strength.