JPH0459672A - Lightweight molded laminate - Google Patents

Abstract

PURPOSE:To improve the flexural strength of a layer composed mainly of a powder produced by modifying vitreous blast-furnace slag powder with an alkaline aqueous solution by laminating the above layer with a layer composed mainly of the above powder or hydrated calcium silicate. CONSTITUTION:Powder of vitreous blast-furnace slag having a Blaine specific surface area of >=4,000cm<2>/g is treated with an aqueous solution of an alkali such as NaOH having a concentration of >=0.5N at about 90 deg.C for >=30min to adjust the BET specific surface area to 20-140m<2>/g by a glass-dissolution reaction and a hydration reaction. The treated product is washed with water and dehydrated by heating at about 250-800 deg.C to further increase the specific surface area. A slurry is produced by mixing 100 pts.wt. of a main material composed of the surface-modified slag powder or its mixture with hydrated calcium silicate with 1-20wt.% of a polymer additive, 1-20wt.% of synthetic pulp, 1-20wt.% of reinforcing fiber, proper amount of a cationic polymer flocculent and water. The slurry is poured into a mold, dehydrated under pressure to form a core layer and bonded to a surface layer made of natural stone, metal, etc., to obtain the objective light-weight molded article.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a lightweight molded body used for interior materials, heat insulating materials, fixtures, etc. of buildings.

[Prior Art] A molded article containing a calcium silicate compound as a main component is called artificial wood and is widely used as a building material. The manufacturing method is to first add water to siliceous raw materials and calcareous raw materials to form a mixed slurry, and then
React at around °C to form a gel. This is placed in an autoclave and reacted at 190 to 250°C for several hours to synthesize xonotlite. Glass fibers, surfactants, polymer admixtures, etc. are appropriately added to this zonotrite slurry in order to improve toughness if necessary, and the mixture is stirred and mixed.The slurry is then placed in a mold, subjected to pressure dehydration molding, and dried at approximately 120°C. This is a method to obtain a molded body (cement/concrete,
N (1469, Mar, 1986.P37-43)
.

As an example of a laminate made from this calcium silicate molded body, a cement mortar layer is provided on the calcium silicate molded body, and the surface strength and impact resistance are improved by applying glaze and firing on this cement mortar layer. An example is known (JP-A-63-74983). In addition, a mixed layer of calcium silicate crystals, substances mainly composed of carbon, carbides, nitrides, metal oxides, etc. is formed on at least one surface layer of the calcium silicate molded body to suppress the decrease in bending strength and provide insulation. There are also known examples of improved sex (Japanese Unexamined Patent Publication No. 6151)
Publication No. 337).

On the other hand, molded bodies using slag are molded bodies for building exterior materials that are made by solidifying and hardening steel slag at room temperature using phosphoric acid such as hypophosphorous acid or phosphates such as aluminum phosphate as a binder. It has been known.

It is also known to apply EBC paint, glass coating, enamel coating, etc. to the surface of this molded body (Japanese Unexamined Patent Publication No. 62-235845).

A method of modifying vitreous granulated blast furnace slag powder with an aqueous alkaline solution is already known (Japanese Unexamined Patent Publication No. 1252559), and the present inventors have already completed a molded body using this modified slag powder. (Patent Application No. 1-337818). A polymer admixture is usually added to this molded body. The polymer admixture functions as a binder between surface-modified slag particles, and also functions to improve the processability, bending strength, and surface properties of the molded article.

[Problem to be solved by the invention] As mentioned above, it is necessary to increase the content of the polymer admixture in order to improve processability, bending strength, and surface texture, but increasing the amount of the polymer admixture makes the molded article nonflammable. There was a problem with the loss of sexuality.

[Means to solve the problem]

The present invention has been made to solve the above problems,
The main material is a powder obtained by modifying vitreous blast furnace slag powder with an aqueous alkali solution through a glass melting reaction and hydration reaction, and a layer containing a polymer admixture and a layer containing a vitreous blast furnace slag powder are dissolved in an aqueous alkali solution to melt the glass. It has a layer mainly composed of powder or calcium silicate hydrate obtained by modification by reaction and hydration reaction and containing a polymer admixture in a content different from that of the above layer, and the content of the polymer admixture is This purpose is achieved by using the surface layer with a larger amount of water and the core layer with a smaller amount of material.

In addition, it may have a small layer (or a layer) mainly composed of powder obtained by modifying vitreous blast furnace slag powder with an aqueous alkali solution through a glass dissolution reaction and a hydration reaction, or it may have a layer mainly composed of calcium silicate hydrate. For example, in a lightweight molded laminate having one or more material layers, it is possible to give the surface layer a paper-like texture by reducing the amount of polymer admixture in the surface layer and blending synthetic pulp or non-combustible pulp. In addition, the surface layer made of natural stone, metal, etc. and the core layer made mainly of powder obtained by modifying vitreous blast furnace slag powder with an alkaline aqueous solution through a glass dissolution reaction and a hydration reaction are bonded together. The heat resistance and decorative properties of the surface can be increased by means of a lightweight molded laminate having an adhesively bonded structure.The present invention also provides such means.

Slag (surface-modified slag) powder obtained by modifying vitreous blast furnace slag powder through a glass melting reaction and hydration reaction is produced by treating vitreous blast furnace slag powder with an alkaline aqueous solution. The surface is modified by causing a sum reaction. Its shape differs from that of xonotrite, in that it is spherical or like a bunch of grapes with overlapping spheres. The main hydration product is tobermorite or similar minerals. The raw material vitreous blast furnace slag may be granulated slag, granulated slag, or the like. The particle size should be fine, for example 400 in Blaine specific surface area.
0CIIY/g or more, especially 8000-14000CIl
A value of about 1/g is suitable. In order to obtain particles having such a particle size, they can be pulverized using a pulverizer, classifier, etc., if necessary. The specific surface area of the raw material slag affects the physical properties of the lightweight molded article of the present invention, particularly the bulk specific gravity. The alkaline aqueous solution is preferably a caustic alkaline solution such as caustic soda or caustic potash, and the concentration is preferably 0.5N or higher, particularly IN or higher. In practice, caustic soda is easy to use. A combination of alkalis is also effective. It is also effective to combine an appropriate amount of sodium carbonate with caustic soda. The processing time varies depending on the processing temperature, etc., but is 30 minutes or more, and usually 1 hour to 1 hour.
It takes about 0 hours. In order to promote the reaction, the treatment temperature should be higher, and in practice it is about 90°C.

Alternatively, a hydrothermal reaction over 100°C may be used.

This alkali treatment causes a glass dissolution reaction and a hydrate formation reaction to occur on the surface of the glassy blast furnace slag particles. As a result, the slag surface becomes porous and the BET specific surface area becomes 2.
0 to 140n(/gg, preferably 40%/g or more,
More preferably, it is 90 rrr/g or more.

After alkali treatment, wash with water to remove the alkali before use. The manufacturing method of such surface-modified slag is described in
It is disclosed in Japanese Patent No. 7093 and Japanese Patent Application Laid-open No. 1-252559. This surface modified slag has 250 to 80
By heating and dehydrating at about 0°C, preferably about 450°C, depending on the initial state, for example,
BET specific area 100n (/g is 120~140r
It can be increased to about d/g. At this time, it is important to select temperature and time conditions that will not cause sintering due to heating and dehydration.

Use of this heated and dehydrated slag is preferable because specific strength and moisture absorption and desorption properties can be improved.

Calcium silicate hydrate is obtained by adding water to a siliceous raw material and a calcareous raw material and causing a heating reaction, and acicular or fibrous crystalline ones such as dunotolite and tobermorite are preferable. The blending weight ratio of the surface-modified slag and the above calcium silicate hydrate is 10:0 to 0:10, preferably 9:1 to 1:9, more preferably 7:3 to 3.
The near range is appropriate.

The surface-modified slag or calcium silicate hydrate-based layer of the present invention contains at least one of a polymer admixture, synthetic pulp, or reinforcing fiber.

The polymer admixture is preferably one that adheres uniformly to the surface-modified slag particles, and various rubber latexes, synthetic resin emulsions, etc. can be used. Rubber latex includes, for example, natural rubber latex and styrene-butadiene copolymer,
Synthetic resin emulsions include, for example, ethylene-vinyl acetate copolymer, vinyl acetate polymer, acrylic acid ester polymer, vinylidene chloride polymer,
It is an emulsion of vinyl chloride polymer, etc. The amount of the polymer admixture added is suitably about 1 to 20%, particularly about 3 to 10% by weight of the solids relative to the surface-modified slag or the sum of the surface-modified slag and calcium silicate hydrate. 1
If it is less than %, the improvement in strength and machinability will be insufficient,
On the other hand, if it exceeds 20%, a decrease in fire resistance becomes a practical problem.

Synthetic pulp is made into pulp by imparting hydrophilicity to synthetic resin, mainly polyolefin, and includes polyethylene valves, polypropylene valves, and the like. A suitable weight ratio to the surface-modified slag is about 1 to 20%, particularly about 3 to 10%. If it is less than 1%, improvements in machinability and surface gloss will be insufficient, while if it exceeds 20%, fire resistance will decrease.

The reinforcing fibers include inorganic fibers such as glass fibers and carbon fibers, synthetic fibers, and natural fibers. Synthetic fibers include polyvinyl alcohol fibers, polyethylene fibers, aramid fibers, etc., and natural fibers include pulp, cotton, mineral fibers, etc. Among these, glass fiber is particularly preferred in terms of nonflammability and cost. The amount of reinforcing fibers added depends on the specific gravity of the fibers, but the weight ratio to the surface-modified slag is about 1 to 20%, especially 5 to 1%.
Approximately 0% is appropriate. If it is less than 1%, the reinforcing effect is not practically effective, while if it exceeds 20%, it becomes difficult to ensure uniform dispersion.

The surface-modified slag or silicic acid hydrate-based layer of the present invention can also contain other components. Examples of other components include polymer admixtures, flocculants, lightweight aggregates, dispersants, pigments, hydraulic layer coatings, and the like.

By adding a flocculant to the polymer admixture, the adsorption of the polymer admixture to the surface-modified slag can be increased. Although there are inorganic flocculants such as aluminum sulfate, organic flocculants, particularly cationic polymer flocculants, are preferable for the molded article of the present invention. Examples of cationic polymer flocculants include quaternary amine compounds such as polydialkylaminoalkyl acrylate, polyaminomethylacrylamide, polyvinylpyridinium halide salt, and polyvinylimidacillin. In the case of a cationic polymer flocculant, the amount of flocculant added is 1 part by weight (
It is preferably about 0.05 to 0.2 parts by weight based on the weight of the solid matter.

The lightweight aggregates are pearlite, shirasu balloons, etc., and if the amount added exceeds 100% by weight relative to the surface-modified slag, the strength, workability, etc. of the molded product will decrease, which is not preferred.

The dispersant is added for the purpose of dispersing polymer admixtures, reinforcing fibers, etc., and improving the fluidity of the kneaded slurry, and includes naphthalene sulfonate formalin high condensates, melamine sulfonic acid compounds, and the like.

Pigments are used to color molded objects, and include inorganic pigments such as lead white, red lead, yellow lead, ultramarine blue, navy blue, cobalt oxide, titanium dioxide, titanium yellow, hengara, iron black, molybdenum red, litharge, and aluminum powder; Organic pigments such as ab-based pigments and phthalocyanine-based pigments can be used.

The hydraulic plaster may be any of α-type and β-type hemihydrate stones, anhydrite stones, etc., but from the viewpoint of cost, baked stone plaster containing β-type hemihydrate stones as a main component is preferable. The amount of gypsum added is 10 to 10% by weight relative to the surface-modified slag.
A suitable amount is about 150%, preferably about 30 to 70%. If it is less than 10%, the effect of improving bending strength will be small, while if it exceeds 150%, machinability and specific strength will decrease. If necessary, a setting regulator for gypsum, such as sodium citrate, can be further added.

One embodiment of the laminate of the present invention has at least a layer mainly composed of surface-modified slag powder and a layer mainly composed of surface-modified slag or calcium silicate hydrate. These layers impart different characteristics to the laminate by varying their formulation. For example, wear resistance, bending strength, etc. can be improved by increasing the content of polymer admixtures in the layer used as the surface layer, and by reducing the amount of polymer admixtures in the layer used as the core layer. Moisture properties, nonflammability, etc. can be improved. By reducing the amount of polymer admixtures on the surface layer and adding natural pulp instead, it is possible to give the surface a paper-like texture. Conventionally, molded objects are colored. In some cases, the entire layer contains pigment, but by including pigment in the surface layer, it is possible to color the laminate while minimizing changes in the physical properties of the laminate.A typical embodiment of this is to laminate the surface layer on both sides of the core layer. This is how it was done.

In that case, calcium silicate hydrate can be used as the main material for one or both of the surface layers, and surface-modified slag can be used as the main material for the core layer. Another embodiment is a two-layer laminate consisting of one surface layer and one core layer.

An example of how this laminate is used is to attach the core layer to the framework of the building. In these embodiments, the surface layer may have a thickness of about 1 to 3 layers, and the core layer may have a thickness of about 5 to 20 layers. Yes. Two or more core layers can be provided. Bending strength can be increased by laminating roving cloth or the like between the surface layer and the core layer.

The method for forming this laminate includes surface-modified slag,
A mixture containing calcium silicate hydrate, polymer admixture, etc., and water is first kneaded. When reinforcing fibers, flocculants, synthetic pulp, lightweight aggregates, thickeners, dispersants, pigments, etc. are added, they are added before or during kneading. If there is a risk that air bubbles may be mixed into the kneaded slurry and cause defects in the molded product, an antifoaming agent may be added or defoaming may be carried out under reduced pressure during or after kneading. The slurry obtained by kneading is usually sequentially poured into a mold such as a mold, and pressure dehydration is repeated. Depending on the composition of the slurry or the equipment used, it is also possible to first form a laminate of the slurry and then pressurize and dehydrate it to form a laminate all at once.

In order to improve uniform dewatering and molding efficiency, wire mesh, filter paper, filter cloth, perforated plates, etc. are used on the pressurizing surface, units that can perform vacuum dehydration and defoaming are incorporated, and embossing is used to improve the design of the surface. You can also incorporate plates. Further, the molded product after pressure dehydration can be cut into a predetermined shape. Pressurization should be done at a pressure that allows dehydration to a specified degree.
For example, the bulk specific gravity of the molded article may be adjusted to a predetermined value, which is usually 10 to 100 kgf/cm2, preferably 20 to 60 kgf/crA.

Drying should be performed to the extent that moisture inside the molded body can be removed and crystallization water of the surface-modified slag remains, for example, 100 to 180%.
It may be dried by heating at about 110 to 150°C, preferably about 110 to 150°C. In order to prevent the molded product from cracking due to drying, it is also preferable to first pre-dry it at about 60 to 80°C. The lightweight molded product thus obtained has a composition obtained by removing water from the kneaded material, and has a bulk specific gravity of 0.2 to Ig/c.
It is a porous body of about Ill, preferably about 0.4 to 0.6 g/c111.

The surface of this laminate can be finished by pasting a metal sheet, thermally spraying ceramic, or applying paint.

Another embodiment of the present invention has a structure in which one surface layer made of natural stone, metal, etc. and one core layer mainly made of surface-modified slag powder are joined via an adhesive. In this embodiment, adhesive is applied to natural stone, metal, etc., slurry is poured onto the adhesive, pressure dehydration molding is performed, and then drying is performed. Pressurized dehydration conditions and drying conditions may be the same as described above.

[Effect]

By providing a layer mainly made of surface-modified slag powder, the weight of the laminate is reduced and its bending strength, moisture control properties, etc. are improved. By combining this with a layer mainly composed of surface-modified slag powder or calcium silicate hydrate, various physical properties of the laminate are improved or various functions are imparted. For example, the core layer can be primarily responsible for lightness, workability, humidity control, nonflammability, etc., and the surface layer can be responsible for aesthetics, scratch resistance, precision, etc.

〔Example〕

Example 1 Glassy blast furnace slag (Shinmanufactured by Nippon Kokan Keihin Steel, granulated blast furnace slag) was milled in a ball mill to a Blaine specific surface area of 4500c1.
The powder was pulverized to 11/g and used as a raw material for classification using an air classifier to obtain fine powder slag with a Blaine specific surface area of 14,000 cffl/g.

This fine powder slag was added at a rate of 5g to 100g of NaOH solution at a temperature of 90°C and a concentration of 3N, and stirred for 3 hours to achieve a BET specific surface area of 100g/g.
A surface-modified slag was obtained. This surface-modified slag was sufficiently washed with water to remove alkaline content, dried, and used as a raw material for producing a laminate.

For 100 parts by weight of surface-modified slag, 8 parts by weight of E glass fiber, 30 parts by weight of carboxy-modified styrene-butadiene copolymer latex as a polymer admixture, 3 parts by weight of synthetic pulp, 3 parts by weight of cationic flocculant, pigment. The yellow of dipyroxide color (Ti-31-Ni series,
3 parts by weight (manufactured by Dainichiseika Chemical Co., Ltd.) and 350 parts by weight of water were added and kneaded, and this slurry was poured into a mold and gradually dehydrated under pressure to form a surface layer.

100 parts by weight of surface-modified slag, 5 parts by weight of E-glass fiber, and carboxy-modified styrene as a polymer admixture.
5 parts by weight of butadiene copolymer latex, 0.5 parts by weight of cationic flocculant, 710 parts by weight of Shirasu Balu, and 3 parts by weight of water.
70 parts by weight was added and kneaded, and this slurry was injected onto the surface layer and gradually dehydrated under pressure to form a core layer. This pressurized dehydrated body having a two-layer structure was dried at 60°C for 15 hours and then at 110°C for 5 hours to obtain a laminate with a surface layer of 5 mm and a core layer having a valence of 20.

Example 2 Example 2 was carried out in the same manner as in Example 1, except that the polymer admixture in the surface layer was changed from carboxy-modified styrene-butadiene copolymer latex to acrylic-modified epoxy resin emulsion.
A laminate having a layered structure was obtained.

Example 3 After the surface layer was dehydrated under pressure, a glass fiber roving cloth impregnated with 511IIn membrane acrylic modified epoxy resin was laid on top of it, and the core layer slurry was poured over it, but the same as Example 1. A laminate having an intermediate halo ring cloth was obtained.

Comparative Example 1 A single-layer product having the same composition as the surface layer of Example 1 and having a thickness of 25 mm was manufactured in the same manner as in Example 1.

Comparative Example 2 A single-layer product having the same composition as the core layer of Example 1 and having a thickness of 25 circles was manufactured in the same manner as in Example 1.

The physical properties of each of these molded bodies were measured and the results are shown in the table below.

Established.

[Effects of the Invention] According to the present invention, it is possible to improve the surface properties of bending strength while ensuring nonflammability, or it is possible to make improvements such as coloring or giving a paper-like texture to the surface without impairing the physical properties. .

The method for measuring the above physical property values is as follows.

Bending strength + Based on JIS A 1106-1976. The test specimen size is 40II in width! It was set as lTl×length 160 mm.

Processability: Cutability with a saw, cutability with a plane,
The nailing performance was evaluated in four grades: ◎, ○, △, and × in descending order of good.

Surface quality: Visually inspected for gloss, powder, etc. in descending order of ◎,
Evaluation was made in four stages: ○, △, and ×.

Fire resistance: The 1 hour fire resistance was determined according to JIS A 1304.

Claims (3)

[Claims] (1) It has at least one layer mainly composed of a powder obtained by modifying vitreous blast furnace slag powder with an alkaline aqueous solution through a glass dissolution reaction and a hydration reaction, or a layer mainly composed of calcium silicate hydrate. A lightweight molded laminate having one or more layers that (2) The main material is a powder obtained by modifying vitreous blast furnace slag powder with an alkaline aqueous solution through a glass melting reaction and hydration reaction, and a layer containing a polymer admixture and a vitreous blast furnace slag powder are modified with an alkali aqueous solution. The main material is powder or calcium silicate hydrate obtained by modifying glass by melting reaction and hydration reaction, and has a layer containing a polymer admixture in a content different from that of the above layer, one of which is Lightweight molded laminate with one surface layer and one core layer (3) The first surface layer made of natural stone, metal, etc. and the first core layer made of powder obtained by modifying glassy blast furnace slag powder with an alkaline aqueous solution through a glass dissolution reaction and a hydration reaction are bonded together. Lightweight molded laminate with structure bonded via adhesive