JPH04231545A - Pollution-resistant natural rock material - Google Patents

Abstract

PURPOSE:To obtain a pollution resistant natural rock material excellent in bending strength of an natural rock material, impact resistance, adherence to grounds such as mortar, and provided with excellent characteristics against various kinds of stains from the front and rear of the rock material before and after execution. CONSTITUTION:The rear of an ultrathin rock material 2 is lined and reinforced with coarsely-woven cloth 3 and corrosion-resistant resin 4, the reinforced is uneven and, at the same time, fluorine corrosion resistant layer 1 is formed on the front of the rock material. According to the constitution, bearing strength of the ultrathin natural rock material, impact resistance, adherence and pollution resistance are excellent.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to ultra-thin natural stone. More specifically, the present invention relates to a stain-resistant natural stone that is lightweight, strong, and has excellent workability, and which does not reduce the gloss, hue, and texture of the surface of the natural stone after installation.

0002

[Prior Art] Ultra-thin natural stone has been produced using a thin slicing technique using a diamond cutter.
Although this natural stone has excellent properties in terms of weight reduction, it is extremely thin, so it has low bending strength and impact resistance, and in addition to problems with transportability and workability, it also has problems with ease of transportation and construction. There are problems with dirt due to penetration of various types of sewage and oil, adhesion of dust, and long-term weather resistance due to rainwater and light.

[0003] In order to improve the bending strength and impact resistance in order to improve such drawbacks, there is a method of reinforcing the back side of natural stone with fiber cloth/resin (Japanese Patent Publication No. 51-3873).
No. 1, Japanese Patent Publication No. 51-48972) have been proposed. However, although this method can improve the penetration of sewage from the back side of the stone, it also prevents various types of dirt and grime from entering the stone surface.
For example, it is not possible to greatly improve the long-term weather resistance against stains caused by sewage or oil penetration, or against rainwater, natural light, or artificial light, and it is insufficient for the long-term stable use of ultra-thin natural stones.

0004

[Problems to be Solved by the Invention] The present invention takes advantage of the lightweight characteristics of ultra-thin natural stone, and at the same time significantly improves its bending strength and impact resistance, which are one of its drawbacks.
As it is extremely thin, it is especially easy to get dirt and dust due to penetration of various types of sewage and oil from the front and back surfaces of the stone, as well as damage to the luster, hue, and texture of the stone surface due to long-term exposure to rainwater, light, etc. This effectively prevents deterioration over time. In particular, among natural stones, granite such as marble and white granite are relatively soft and porous, and as they become extremely thin, the strength of the stone decreases.
Stains caused by penetration of sewage, etc. tend to be more noticeable. By solving all the drawbacks of these ultra-thin natural stones, we will be able to improve construction workability by reducing weight, realize design and construction using large-sized natural stones that are difficult to achieve with conventional methods, and provide excellent stain resistance. This effectively and permanently maintains the original texture and luxury of natural stone.

[0005]

[Means to solve the problem] At the same time, the drawbacks of ultra-thin natural stone materials, especially relatively soft and porous granite stones such as marble and white granite, are reduced, such as bending strength, impact resistance, and appearance quality. As a result of intensive research into a method to solve this problem, we have arrived at the present invention. That is, the present invention is an antifouling natural stone material characterized by having a fluorine-based antifouling agent on the surface of the ultra-thin natural stone material, and a coarse reinforcing fabric and a corrosion-resistant resin layer on the back surface.

More specifically, on the surface of ultra-thin natural stone with a thickness of 2 to 12 mm, it has excellent weather resistance (light) and heat resistance.
In addition, while applying a special fluorine-based antifouling agent that has antifouling properties based on water and oil repellency, the back side of the stone is reinforced with coarse reinforcing fabric and corrosion-resistant resin, which eliminates the drawbacks of ultra-thin natural stone. The object of the present invention is to provide a stain-resistant natural stone material that can significantly improve the bending strength and impact resistance, and at the same time, prevent the appearance quality of the stone surface from changing over time after construction.

[0007] The ultra-thin natural stone of the present invention is 2 to 12 mm.
It is a natural stone that is thinly sliced. Applicable raw stones include a wide range of natural stones such as marble, white granite, red granite, black granite, and other granites, but in particular, marble and white granite are relatively soft and porous, and stains are easily noticeable. Effective against colored stones. On the other hand, for hard, dense, and darkly colored stones, changes in gloss and texture over time can be prevented during long-term use, but changes due to various types of sewage and the like are essentially small.

The fluorine-based antifouling agents of the present invention include polytetrafluoroethylene, perfluoroalkyl group-containing acrylic water and oil repellents, perfluoroalkyl group-containing urethane water and oil repellents, and modified products thereof, such as , silicon-modified fluorine-based compounds, alkylene oxide-modified fluorine-based compounds, etc., but especially those that have excellent weather resistance (light) resistance and heat resistance, and also exhibit stain resistance based on water repellency/oil repellency, It is not limited to these. Examples of antifouling agents having such characteristics include emulsified dispersions of polytetrafluoroethylene, high fluorine-containing type (fluorine content in solid content is 35% or more) acrylic water and oil repellents,
Particularly preferred are silicone-modified fluorine-based water and oil repellents.

[0009] Coarse reinforcement fabrics include knitted fabrics and non-woven fabrics composed of glass fibers, carbon fibers, polyester fibers, high strength and high elasticity polyethylene fibers, and aromatic polyamide fibers. Coarse woven fabrics are particularly preferred from the viewpoint of the reinforcing effect of ultra-thin natural stones, which is one of them, and the ease of combining stones and reinforcing fabrics using corrosion-resistant resin. In general, it is preferable for such fabrics to have high strength and low elongation, and to achieve this, it is also effective to use a combination of glass fibers, carbon fibers, etc., and polyester fibers, high strength and high elasticity polyethylene fibers, etc. It is true. Furthermore,
These coarse reinforcing fabrics are made of alkali-resistant resins such as methylolmelamine resins, acrylic resins, unsaturated polyester resins, epoxy resins, and ethylene vinyl acetate resins in order to protect them from cement alkalis and improve workability. It can also be used after hard finishing.

[0010] The corrosion-resistant resin in the present invention is a resin that has excellent chemical resistance to various chemicals such as acids, alkalis, oxidizing agents, reducing agents, various salts, and organic solvents.

Such corrosion-resistant resins are usually saturated polyester resins, unsaturated polyester resins such as het acid polyesters, bisphenol A polyesters, and linear vinyl polyester resins, or epoxy resins such as glycidyl ether resins. , glycidyl ester type, glycidyl amine type, linear aliphatic epoxide type, alicyclic epoxide type resin, etc. are used.
Epoxy acrylate resins and bisphenol A polyester resins are preferred from the viewpoint of adhesion to substrates such as stone, reinforcing fabrics, and mortar, reinforcing effects, chemical resistance, and waterproof properties.

[0012] In particular, by using epoxy acrylate resin with excellent corrosion resistance, good reinforcement /
In order to provide a waterproof effect, a vinyl monomer such as a styrene monomer is added to the resin, and the resin is heated at 20°C for 50 minutes.
After adjusting the viscosity to 0.00 centipoise or less, preferably 100 to 300 centipoise, add the required amount of curing agent or curing accelerator and allow it to penetrate uniformly and sufficiently into the surface layer of the back surface of the stone and the fiber gaps of the reinforcing fabric. It is cured at 140°C for a few minutes to about a week.

Examples of the curing agent and curing accelerator include methyl ethyl ketone peroxide (MEKPO), benzoyl peroxide (BPO), cobalt naphthenate, cobalt octenoate and dimethylaniline. Usually, MEK
PO/cobalt naphthenate type and BPO/dimethylaniline type are used, but especially when room temperature curing is desired,
The use of MEKPO/cobalt naphthenate/dimethylaniline system is effective.

[0014] Next, the method of applying the fluorinated antifouling agent and corrosion-resistant resin in the present invention will be explained. First, fluorine-based antifouling agents are applied only to the surface of ultra-thin natural stone. Specifically, after slicing natural stone to the desired thickness, polishing the surface, and drying, first the back side of the stone is reinforced by lining with a coarse reinforcing fabric and corrosion-resistant resin, and then a fluoride antifouling agent is applied to the surface of the stone. It is applied to form an antifouling layer based on water and oil repellency.

A specific method for applying such an antifouling agent is to apply a specified fluorine antifouling agent with water or a water/organic solvent solution.
After dilution to 1-20% by weight, preferably 2-10% by weight, the equivalent of 20-300 g/m2, preferably 50
Apply an amount equivalent to ~200g/m2 evenly to the stone surface,
After drying, temperature is higher than room temperature and lower than 140℃, preferably 40-1
Cures and forms a film at 00°C for several minutes to several hours. From the viewpoint of ensuring surface quality, it is desirable to apply such an antifouling agent uniformly to the extreme surface layer of the stone surface without any penetration spots.

[0016] In general, natural stone materials with poor homogeneity have slightly different penetration rates of antifouling agent depending on their type, thickness, and degree of dryness. It is difficult to give. In order to solve these problems, it is extremely important to control the degree of dryness of the stone and the viscosity of the antifouling agent liquid, in addition to the type and concentration of the antifouling agent. The degree of dryness of the stone varies depending on the curing conditions of the corrosion-resistant resin used to reinforce the back side of the stone, but after curing, the stone is usually cured at room temperature for at least 24 hours before being subjected to antifouling treatment. In addition, the viscosity of the antifouling agent solution varies somewhat depending on the type and concentration of the antifouling agent used, but in order to prevent excessive penetration from the stone surface and penetration spots, the viscosity should be controlled at 100 to 3000 centipoise, preferably 2.
It is desirable to use it in the range of 00 to 1000 centipoise. If the viscosity of the antifouling agent liquid is less than 100 centipoise, penetration spots will occur, whereas if it is more than 3000 centipoise,
Surface adhesion spots of antifouling agents are likely to occur.

Next, a method of applying a corrosion-resistant resin to the back surface of a stone according to the present invention will be explained. Such application methods include (1) a method in which a coarse reinforcing fabric is laminated on the back side of an ultra-thin natural stone, and then a corrosion-resistant resin is applied or injected; ■A method in which a corrosion-resistant resin is applied to the back side of ultra-thin natural stone, a coarse reinforcing fabric is laminated, and then another corrosion-resistant resin is applied or injected. ■
There is a method of pre-impregnating and curing a coarse reinforcing fabric with a corrosion-resistant resin to form a sheet-like prepreg, then applying the corrosion-resistant resin to the back side of an ultra-thin natural stone material, and laminating and adhering the prepregs. The amount of corrosion-resistant resin applied varies depending on the type and thickness of the applied natural stone, the type of reinforcing fabric, and the purpose of the stone, but usually
100-1500g/m2, preferably 200-50
Select and use within the range of 0g/m2. The curing conditions for the corrosion-resistant resin are preferably 20 to 140°C, particularly 20 to 60°C, from the viewpoint of preventing warping of the lining and reinforcing stone and maintaining the physical properties of the stone and surface quality, such as gloss and hue. The back surface of the natural stone material to be reinforced with backing has an appropriate roughness, and exhibits better adhesion as it dries sufficiently.

In the present invention, one of the methods for improving the adhesion between the reinforcing lining surface and mortar cement or dry adhesive is to form irregularities on the reinforcing lining surface using a corrosion-resistant resin. Such methods include: (1) A method of controlling the amount of corrosion-resistant resin applied by utilizing the height difference of the coarse reinforcing fabric. ■ Add 100 to 1500 inorganic particles such as silica sand that have good adhesion to the base such as mortar on the surface of the corrosion-resistant resin.
A method of applying an amount equivalent to g/m2 and then curing it. (2) A method can be applied in which a releasable uneven sheet or plate is pressed onto the surface of a corrosion-resistant resin, and after curing, it is peeled off and shaped.

[0020] In the present invention, the surface of natural stone means the normally polished surface, and the back surface means the rough surface.

[0021]

[Examples] The present invention will be specifically explained with reference to Examples below. In the examples, all percentages are by weight.

[0023] The properties of the antifouling natural stone were measured by the following method.

1. Bending strength (bending breaking load) After cutting each stone into a size of 5 cm wide x 20 cm long, J
It was measured by the method specified in IS A 1408 (sample size: 5 cm x 20 cm, bending speed: 1 mm/min, radius of curvature of bending bar: 5 mm, distance between fulcrums: 15 cm).

2. Impact resistance Based on the method specified in JIS A 1421 (sample size: 20 cm x 20 cm, sample support: full support on sand, weight: W1 -1000 g, falling height: 100 cm)
), those with no change in the stone surface after the impact test were rated ○, those with cracks were △, and those with broken stones were rated ×.

3. Adhesive A compounded mortar equivalent to a thickness of 50 mm (Adkeep: manufactured by Tokuyama Soda Co., Ltd.) was adhered to the back of a 10 cm square stone, and after curing at room temperature for 3 weeks, the adhesive strength was tested using a Kenken tensile tester. It was measured.

4. Stain resistance: 2 cc/liter (l) of blue ink, 5 cc/l of heavy oil B, and 100 g of clay on the front and back surfaces of a 10 cm square stone.
Drop an amount equivalent to 10 cc of contaminated water containing /l, cover with a film, leave it at room temperature for one week, wipe it off with a wet towel, and after drying, check the degree of contamination on the front and back of the stone. , Those with stains were rated △, and those with noticeable stains were rated ×.

5. Water-repellent small droplets of isopropyl alcohol/water mixed were dropped onto the surface of a stone measuring 10 cm square in length and width, and the state of wetting was rated from grade 1 (poor) to grade 5 (good).

[0028]

[Table 1]

6. Oil repellency The oil repellency of the stone surface was measured in accordance with the AATCC-118-1975 oil repellency evaluation, and was graded 1st grade (poor) to 8th grade (good).
I judged it.

7. Field stain resistance After adhering the back side of a 50 cm square stone horizontally to the mortar cement base, after an outdoor exposure test for 2 years, there was no change in the appearance quality (gloss, hue) of the stone surface. What you don't have ◎,
Visual judgment was made as ○ if the change was subtle, △ if the change was small, and × if there was a change.

8. Workability This is a comprehensive indication of the difficulty of horizontal lifting workability and adhesion workability when using mortar adhesive construction using stone materials with a width of 1m x length of 1.5m, compared to stones with a thickness of 12mm or more. If it was easy, it was marked as ○, and if it was difficult, it was marked as ×.

Example 1 Polyester long fibers (1
000d-192f, yarn strength 8 g/denier) coarse woven fabric (weave density 20 fibers/inch in length and width) was layered, and 100 parts of epoxy acrylate corrosion-resistant resin (Neopol 8250L, manufactured by Nippon U-Pica Co., Ltd.), 8% naphthenic acid was layered. After applying an equivalent amount of 450 g/m2 of a mixed solution consisting of 0.1 part of cobalt and 1.0 part of 55% methyl ethyl ketone peroxide (Permec N: manufactured by NOF Corporation), it was cured at 25°C for 5 days to form fine particles on the back surface. A reinforcing layer with roughness was formed.

Next, a polytetrafluoroethylene (PTFE) antifouling agent (solid content 2
0%, water/isopropyl alcohol = 80%/20% dispersion) 100 parts, water/turpentine oil = 70 parts/30 parts of a mixed liquid consisting of 100 parts of a W/O type emulsion liquid, an equivalent amount of 200 g/m2. After coating and drying, 100℃
A fluorine-based antifouling layer was formed on the surface of the stone by heat treatment for 30 seconds.

Example 2 Polyester long fibers (1
000d-192f, yarn strength 8 g/denier) coarse woven fabric (weave density 20 fibers/inch in length and width) was layered, and 100 parts of epoxy acrylate corrosion-resistant resin (Neohole 8250L, manufactured by Nippon U-Pica Co., Ltd.), 8% naphthenic acid was layered. Cobalt 0.1 part, 55% methyl ethyl ketone peroxide (Permec N: NOF Corporation) 1.0 part, 1
After applying a mixed solution consisting of 0.01 part of 0.00% dimethylaniline (reagent) in an amount equivalent to 450 g/m2, it was cured at 25° C. for 3 days to form a reinforcing backing layer having fine irregularities on the back surface.

Next, a perfluoroalkyl group-containing acrylic water and oil repellent (LS32
0: Meisei Chemical Industry Co., Ltd.) 100 parts, W/O emulsion liquid 10 consisting of water/turpentine oil = 70 parts/30 parts
A mixed solution consisting of 0 parts was applied in an amount equivalent to 300 g/m2, dried, and then heat treated at 100° C. for 30 seconds to form a fluorine-based antifouling layer on the stone surface.

Example 3 Polyester long fibers (
1000d-192f, yarn strength 8g/denier) coarse woven fabric (weave density 20 pieces/inch in length and width) was layered, and 100 parts of epoxy acrylate corrosion-resistant resin (Neopol 8250L, manufactured by Nippon U-Pica), 8% naphthenic acid was layered. 0.1 part of cobalt, 1.0 part of 55% methyl ethyl ketone peroxide (Permec N: manufactured by NOF Corporation),
After applying a mixed solution consisting of 0.1 part of 100% dimethylaniline (reagent) in an amount equivalent to 550 g/m2, and applying an amount equivalent to 500 g/m2 of silica sand No. , to form a reinforcing backing layer having fine irregularities on the back surface.

[0037] Next, the same PTFE antifouling agent as in Example 1 was applied to the white granite surface (worn side) in an amount equivalent to 300 g/m2, dried, brushed with a cotton cloth, and then heat-treated at 100°C for 30 seconds. A fluorine-based antifouling layer was formed on the stone surface.

Comparative Example 1 Marble backed and reinforced was obtained in the same manner as in Example 1, except that a fluorine-based antifouling layer was not formed on the surface of the stone.

Comparative Example 2 Except for not lining and reinforcing with coarse fabric and corrosion-resistant resin,
In the same manner as in Example 1, marble having antifouling properties only on the stone surface was obtained.

Comparative Example 3 A fluorine-based antifouling layer was formed on the surface of the stone in the same manner as in Example 1, except that the coarse fabric for reinforcement was not used. On the other hand, a corrosion-resistant resin with a flat surface was formed on the back of the stone. Obtained only marble.

[0041] Regarding the various ultra-thin natural stones obtained in the above Examples and Comparative Examples, bending strength, impact resistance, adhesion,
Table 2 summarizes the results of evaluating stain resistance, water repellency, oil repellency, field stain resistance, and workability.

[0042]

[Table 2]

[Effects of the Invention] The antifouling natural stone of the present invention is obtained by adding a fluorine-based antifouling agent to the surface of an ultra-thin natural stone, a coarse reinforcing fabric and a corrosion-resistant resin to the back, and shaping it to have unevenness. The surface of the stone has excellent stain resistance based on water and oil repellency, while the back side of the stone has a good backing reinforcement effect and adhesion to the base, making it excellent against various types of sewage and oils. In addition to exhibiting excellent stain resistance, it can effectively prevent changes in the luster, hue, and texture of stone surfaces over time due to long-term exposure to rainwater, light, etc. It also shows excellent improvement effects on bending strength and impact resistance. Therefore, it is possible to provide a natural stone that is unprecedentedly lightweight, strong, and has excellent stain resistance, which greatly improves workability. It can be used for ceiling materials, exterior wall materials, partition materials, furniture, etc., and its effects are extremely large.

[Brief explanation of the drawing]

[Figure 1]

FIG. 1 is a diagram showing a cross-sectional view of an example of the stain-resistant natural stone material of the present invention, and FIG. 2 is a schematic diagram of the back side of the stone material of FIG. 1.

[Figure 3]

FIG. 3 is a diagram showing a cross section of a stone of Comparative Example 1, and FIG. 4 is a schematic diagram of the back side of the stone of Comparative Example 1.

[Figure 5]

6] FIG. 5 is a diagram showing a cross section of the stone material of Comparative Example 2, and FIG. 6 is a schematic diagram of the back side of the stone material of Comparative Example 2. [FIG.

[Figure 7]

FIG. 7 is a diagram showing a cross section of a stone of Comparative Example 3, and FIG. 8 is a schematic diagram of the back side of Comparative Example 3.

[Explanation of numbers]

1.　Fluorinated antifouling agent 2. Ultra-thin natural stone 3. Coarse fabric for reinforcing lining 4. Corrosion-resistant resin for reinforcing lining

Claims (1)

[Claims] 1. An antifouling natural stone material characterized by having a fluorine-based antifouling agent on the surface of the ultra-thin natural stone material, and a coarse reinforcing fabric and a corrosion-resistant resin layer on the back surface.