JPH0531513B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention improves the waterproofness and water repellency of ceramic exterior wall material compositions, particularly conventional ceramic exterior wall materials, thereby preventing water leakage due to water intrusion, rusting of reinforcing bars, etc.
The present invention relates to a ceramic exterior wall material composition that can prevent frost damage. [Conventional technology] There are various types of exterior wall materials for buildings.
In order to preserve the environment, we have adopted Portland cement, blast furnace cement, slag cement,
Cement raw materials such as lime, gypsum, and calcium silicate, silicic acid raw materials such as silica sand, perlite, silica, and calcium silicate, and/or pulp,
Non-asbestos ceramic exterior wall materials made by adding fibrous raw materials such as wood chips, glass fibers, and organic fibers are gaining popularity. However, this type of ceramic exterior wall material has a large number of pores on its surface and inside, so it has high water absorption properties, and therefore cannot prevent water leakage, rusting of reinforcing bars, and frost damage. . Therefore, for this ceramic-based exterior wall material, methods are known and widely used, such as applying siliconate or organosilane to the exterior wall made of this material, or adding silicone oil internally to the exterior wall material composition. . [Problems to be solved] However, since the siliconate waterproofing agent applied to the exterior walls is strongly alkaline, there is a risk that it will corrode the metal fittings to which the boards are attached, and there are restrictions on its handling. Since the surface is easily contaminated, there is an aesthetic problem, and furthermore, it has the disadvantage of poor durability. Furthermore, although the organosilane used for this coating has excellent alkali resistance and resistance to permeation of chlorine ions, the organosilane permeates only into the very surface of the concrete. This has the disadvantage of losing its waterproof properties if it is damaged or deteriorates due to outdoor exposure.
Siliconate and organosilane also have the disadvantage that they require a post-process of coating after constructing the outer wall using an outer wall material. Furthermore, the silicone oil added to the ceramic exterior wall material composition before molding is typically dimethyl silicone oil or long-chain alkyl group-containing silicone oil, which is a chemically inert neutral substance. Because of this, it does not cause corrosion problems, and since it is added internally, it has good water repellency and does not cause any pollution problems to the surrounding environment. It is considered to be publicly known (Special Publication No. 50-27053)
Publication No. 1987-33812, Japanese Patent Publication No. 1983-33812
Publication No. 42272, Japanese Patent Application Publication No. 113655-1987, Japanese Patent Application Publication No. 113655
57-92561, JP-A-59-232954)
However, in these known methods, in order to significantly reduce the water absorption of the exterior wall material obtained from this composition, it is necessary to add a considerably large amount of silicone oil, and therefore it is not economical. It has the disadvantage of being lacking. [Means for Solving the Problems] The present invention relates to a ceramic exterior wall material composition that solves these disadvantages, and which contains a cement raw material as a main component and a silicic acid raw material and/or a fibrous raw material. The non-asbestos ceramic exterior wall material composition has a viscosity of 5 to 25°C at 25°C.
It is 1000cS (Here, R ¹ is a monovalent hydrocarbon group having 1 to 6 carbon atoms, R ² is a hydrogen atom or the same monovalent hydrocarbon group as R ¹ , and R ³ is a monovalent long chain alkyl group having 4 to 12 carbon atoms. The composition is characterized in that a long-chain alkylorganohydrodiene polysiloxane represented by the groups a and b are numbers satisfying 0.50<b/a+b<0.95 is added to and mixed with the composition. That is, as a result of various studies in order to develop a ceramic-based exterior wall material composition that improves the drawbacks of conventional products as described above, the present inventors have developed a composition consisting of a known cement raw material, a silicic acid raw material, and/or a fibrous raw material. When long-chain alkylorganohydrodiene polysiloxane is added to a non-asbestos ceramic exterior wall material composition, the molded product obtained by casting and curing the ceramic exterior wall material composition has sufficient water absorption resistance. In addition, since this long-chain alkylorganohydrodiene polysiloxane is directly added to the ceramic exterior wall material composition, there is no need for post-treatment of applying it to the exterior wall, and this also means that the amount added 5 for ceramic-based exterior wall material compositions
The present invention was completed after confirming that it is economically advantageous since it only requires less than % by weight. [Function] This will be explained in more detail below. The ceramic exterior wall material composition of the present invention is a known non-asbestos ceramic exterior wall material composition to which long-chain alkylorganohydrodiene polysiloxane is added. 100 parts by weight of cement raw materials such as Portland cement, blast furnace cement, slag cement, lime, gypsum, and calcium silicate are combined with silica sand, perlite, silica,
10 to 200 silicic acid raw materials such as calcium silicate
1 to 50 parts by weight and/or fibrous raw materials such as pulp, wood chips, glass fibers, and organic fibers may be mixed uniformly. In addition, the long-chain alkylorganopolysiloxane added to this non-asbestos ceramic exterior wall material composition contains a long-chain alkyl group bonded to a silicon atom and a hydrogen atom in its molecule. formula It is indicated by. Here R ¹ is a methyl group, an ethyl group,
Alkyl groups such as propyl and butyl groups, alkenyl groups such as vinyl and allyl groups, phenyl groups,
Aryl groups such as tolyl groups, or chloromethyl groups, trifluoropropyl groups, cyanoethyl groups, and mercapto groups in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms, cyano groups, mercapto groups, etc. unsubstituted or substituted same or different monovalent hydrocarbon groups having 1 to 6 carbon atoms selected from propyl groups, etc.;
Preferably, the group is a methyl group, R ² is a hydrogen atom or the same monovalent hydrocarbon group as R ¹ , and R ³ is a hydrogen atom or the same monovalent hydrocarbon group as R 1 , and if R 3 has less than 3 carbon atoms, the polysiloxane will be decomposed in the exterior wall material composition; If the number of atoms is 13 or more, the dispersibility of the polysiloxane in the exterior wall material composition decreases, so polysiloxanes with 4 to 12 carbon atoms, such as butyl group, hexyl group, octyl group, decyl group, dodecyl group, etc. Preferably 6 to 10 long chain alkyl groups. Furthermore, when a and b indicate the content of hydrogen groups in the substituents, b/a+b is less than 0.5 or greater than 0.95, sufficient water absorption is imparted to the exterior wall material made from this composition. Since there is no such thing, it is assumed that the number satisfies 0.5 to 0.95. Furthermore, since this long-chain alkylorganohydrodiene polysiloxane imparts water absorption resistance to the exterior wall material made from this composition, it must have a viscosity in the range of 5 to 1000 cS at 25°C. However, from the viewpoint of improving workability, it is better to set it to 100 cS or less. Note that if the amount of the long-chain alkylorganohydrodiene polysiloxane added is less than 0.01% by weight based on the raw material solid content of the ceramic exterior wall material composition, the desired water absorption resistance cannot be obtained, and if it is more than 5% by weight, This will increase costs and make it impractical.
It may be in the range of 0.01 to 5% by weight, preferably 0.01 to 1.0% by weight, more preferably 0.1% by weight.
It may be in the range of ~0.5% by weight. [Example] Next, examples of the present invention will be given. In the examples, % indicates weight %, viscosity indicates a value measured at 25°C, and this water absorption rate indicates a value measured by the following method. It is something that [Measurement of water absorption rate] A molded article made from a non-asbestos ceramic exterior wall material composition was immersed in tap water for 24 hours, and then its weight was measured to determine its water absorption rate. Examples 1 to 9 50g of Portland cement and 50g of silica sand (No. 7)
g, Perlite Topue #31 [product name manufactured by Showa Kagaku Kogyo Co., Ltd.] 10 g, 5.5 g of pulp pieces of 5 x 5 x 0.5 mm,
The long-chain alkyl organohydrogen polysiloxane (siloxane A to D) shown below was added to 80 g of tap water and the total amount of solids excluding tap water.
Ceramic exterior wall material composition I by adding in the amounts shown in the table
I made it. ...Octyl methylhydrodiene polysiloxane [Siloxane A] (viscosity 21cS), ...Octyl methylhydrodiene polysiloxane [Siloxane B] (viscosity 14cS), ...hexylmethylhydrodiene polysiloxane [siloxane C] (viscosity 27cS), ...Decyl methylhydrodiene polysiloxane [Siloxane D] (viscosity 35 cS) Next, this composition was stirred at high speed at 700 rpm for 3 minutes, then poured into a wooden frame and poured into a container at 60°C and 95% relative humidity. It was left to mature for 12 hours, and then dried for 6 hours in a hot air circulation constant temperature bath at 105°C to make a 6 x 4 x 15 cm molded product with a specific gravity of 1.1.The water absorption rate of this product was measured. The results shown in Table 1 were obtained, and all of these had a low water absorption rate of 25% or less, indicating excellent water absorption.

[Table] Comparative Examples 1 to 9 Non-asbestos ceramic exterior wall material compositions prepared in Examples 1 to 9, ...Octylmethylpolysiloxane [Siloxane E] (viscosity 55cS), ...Methylhydrodiene polysiloxane [Siloxane F] (viscosity 18cS), ...Dimethylpolysiloxane [Siloxane G]
(viscosity 20cS), ...Ethyl methylhydrodiene polysiloxane [Siloxane H] (viscosity 10cS), ...Tetradecylmethylhydrodiene polysiloxane [Siloxane I] (viscosity 52cS), ... Octyl methylhydrodiene polysiloxane [Siloxane J] (viscosity 36 cS) was added in the amount shown in Table 2 based on the solid content to prepare ceramic exterior wall material compositions, and these were prepared in Examples 1 to 3. A molded body was made in the same manner as in Example 9, and the water absorption rate of this body was measured. The results shown in Table 2 were obtained, and the water absorption rate was 35% compared to those of Examples 1 to 9. It was much bigger than that.

【table】

[Table] [Effects of the Invention] The ceramic exterior wall material composition of the present invention differs from conventionally known non-asbestos ceramic exterior wall material compositions in that it is an organohydrocarbon material containing a long chain alkyl group with 4 to 12 carbon atoms. This composition is made by adding diene polysiloxane, and as this composition has excellent waterproof and water repellent properties, exterior wall materials made from this composition will not leak due to water intrusion. ,
Rust and frost damage to reinforcing bars are effectively prevented. Furthermore, the long-chain alkylorganohydrodiene polysiloxane added in the present invention has the advantage of being excellent in economical efficiency, since only a small amount is required and it only needs to be added to the composition before molding.

Claims (1)

[Scope of Claims] 1. A non-asbestos ceramic exterior wall material composition comprising a cement raw material as a main component and a silicic acid raw material and/or a fibrous raw material, which has a viscosity of 5 to 1000 cS at 25°C. a certain expression (Here, R ¹ is a monovalent hydrocarbon group having 1 to 6 carbon atoms, R ² is a hydrogen atom or the same monovalent hydrocarbon group as R ¹ , and R ³ is a monovalent long-chain alkyl group having 4 to 12 carbon atoms. , a, b are numbers satisfying 0.50<b/a+b<0.95).