JP3260274B2 - Flat roof material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a flat roofing material,
In particular, the present invention relates to a flat roof material that is roofed in a state in which a lower layer is partially overlapped with a higher layer.

[0002]

2. Description of the Related Art Conventionally, as a flat roofing material of this type, a flat inorganic plate such as a fiber reinforced cement board mixed with a fiber substance has been frequently used. When these flat roofing materials are installed on the roof, they are installed in a row in a row parallel to the roof ridge, and then in the second row, on the ridge side of the flat roofing material in the first row The parts are partially overlapped, and the roofing work is shifted by about half in the left-right direction, and the third and subsequent rows are similarly finished by partially shifting the roofing work.

[0003] During roofing, the flat roofing material in each row can be roofed by overlapping a considerable portion in the vertical direction (toward the eaves) in order to prevent the ingress of rainwater. There is a problem that rainwater easily enters the interior due to blowing in the rain. this is,
The entire surface of conventional flat roofing materials is often painted with the same water-repellent paint, and the rainwater that hits the exposed parts (the parts that are not superimposed) is round and easy to flow in strong winds. It is easy to penetrate deep into the unexposed part (overlapping part) while maintaining the shape, and the infiltrated rainwater reaches the base plate through the nail hole for fixing to the roof or over the top of the product and causes water leakage Had become.

On the other hand, the water-repellent paint is slippery on the surface, which is dangerous for roofing work and the like, and is expensive.
A flat roofing material in which a water-repellent paint containing sand particles is applied only to the overlapped portion has also been proposed (Japanese Patent Laid-Open No. Hei.
No. 331972). According to this, the space formed by the sand particles and the water repellency of the paint prevent the penetration of rainwater due to the capillary phenomenon, and can prevent excessive wetting of the overlapped portion.

[0005] In this type of flat roofing material, there is also a drawback that rainwater infiltrates also from the abutting portion in the lateral direction, spreads in the lateral direction due to capillary action, and leaks from the nail hole portion for fixing to the roof. Was. As a countermeasure, a flat roofing material is proposed, in which a number of vertically continuous grooves are formed on the superposed upper surface to prevent the rainwater from spreading in the horizontal direction by the grooves to prevent water leakage. (Japanese Utility Model Laid-Open No. 60-35817).

[0006]

SUMMARY OF THE INVENTION The present inventors have been conducting continuous research and development on flat roofing materials. Is effective because it makes it easier for rainwater to flow down.However, if the overlapping portion is also coated with a water-repellent paint as described above, raindrops that become spherical in the exposed portion during strong winds etc. They have experienced deep penetration into certain overlaps, rather than promoting water leakage. In addition, even in the case of a flat roof material in which the water-repellent paint is applied only to the overlapped portion, the rainwater blown into the overlapped portion becomes spherical and easily penetrates into the back.

Furthermore, in the case of a flat roofing material having a number of vertically extending concave grooves formed on the upper surface to be superimposed, it is possible to prevent the spread of rainwater by the capillary phenomenon in the horizontal direction, but it is possible to prevent the spread of rainwater in a strong wind. I also experienced that it was not possible to achieve a sufficient effect on rainwater blowing in the sea. An object of the present invention is to eliminate the above-mentioned inconveniences of a conventionally used flat roof material, and more specifically, to prevent rainwater from leaking in an exposed portion and prevent a strong wind. It is an object of the present invention to provide a flat roofing material that can effectively prevent infiltration of rainwater into a superimposed portion during rain or the like.

[0008]

According to the flat roofing material of the present invention for solving the above-mentioned problems, a coating film is formed on almost the entire surface of the roofing material. Is characterized in that it is a water-repellent coating. The flat roofing material body may be a material forming the main body portion of the conventional flat roofing material body of this type, and a fiber-mixed cement plate containing cement containing pulp fibers as a main component, a cement calcium silicate plate, a slag It may be a cement perlite board, an asbestos cement board or the like.

[0009] The paint applied to substantially the entire surface of the flat roofing material body may be the same kind of paint or different kinds of paints, but at least other portions except for almost the entire overlapping portion. That is, a portion corresponding to the exposed portion is coated so that a water-repellent coating film is formed. The method of forming the water-repellent coating film is arbitrary. When the same type of coating material is used, the overlapped portion and the exposed portion are separately applied. Alternatively, a mixture of a water-repellent such as wax may be used, or a non-water-repellent paint may be applied to the entire surface, and then the exposed portion may be over-coated with the water-repellent paint.

In another aspect of the present invention, the flat roofing material has a coating film formed on almost the entire surface thereof, and the coating film at least over substantially the entire overlapping portion is different from the coating film of the other portion. A coating film having a smaller contact angle with water is used.

Also in this case, after the same type of water-repellent paint is applied to almost the entire surface of the flat roofing material body, water is applied to at least almost the entire area of the overlapped portion (or almost the entire other area). May be overcoated with another paint that forms a coating film having a smaller contact angle with respect to (or another paint that forms a coating film with a larger contact angle with water),
Further, by changing the types and amounts of the components of the paint forming the coating film and the coating material forming the coating film of the remaining portion (mainly the exposed portion) in at least almost the entire area of the overlapping portion,
Thereby, the contact angles to water may be different from each other.

[0012] As an example of differentiating the components, a coating applied to an exposed portion, that is, a coating for forming a coating film having a large contact angle with water is used as a silicone-based defoaming agent or leveling agent. Alternatively, a material having a water-repellent function, such as an aqueous dispersion of wax, may be included. In addition, examples of different blending amounts include extender pigments that are usually mixed as a blending component in paints,
Pigment dispersing agents, emulsifiers, or thickening and anti-settling agents, etc., increase the amount of materials that have the function of dispersing and uniforming the paint in paints to be applied to overlapping parts compared to paints to be applied to exposed parts, Thereby, the contact angle of the coating film with water in at least almost the entire area of the overlapped portion may be made smaller than that of the coating film in other portions.

According to the flat roofing material of the present invention, when the upper flat roofing material is partly overlapped with the lower flat roofing material, the exposed portion becomes a water-repellent coating film when the roofing work is performed. Rainwater drops are easy to flow and do not easily fall and cause water leakage. On the other hand, the non-exposed portion, which is the overlapping portion, is a non-water-repellent coating film or has a contact angle smaller than the contact angle of the exposed portion of the coating film with water. For this reason, in the event of wind and rain, rainwater droplets that infiltrate by blowing from the shingled portion (the end of the overlapping portion),
Alternatively, rainwater that enters due to capillary action becomes harder to flow upward (harder to penetrate) due to increased resistance to upward flow, and the infiltrated rainwater spreads laterally at that location, resulting in the eaves building direction ( Infiltration of rainwater into the roof (in the depth direction) is prevented.

In other words, in the unexposed area, the rainwater does not become granular but spreads laterally on the coating film surface, and a so-called waterproof film is formed there. Therefore, rainwater that is going to infiltrate thereafter is also blocked there, and it hardly penetrates into the nail hole portion fixing the flat roof material, and the waterproofness is improved.

[0015]

【Example】

Example 1 A flat roofing material body 10 made of a fiber-mixed cement board mainly composed of cement mixed with wood pulp and having a shape shown in FIG. 1 was formed, and an upper portion 1 (hatched portion) of the surface was formed. Paints with A composition shown in Table 1 below (A1, A
2), and the lower portion 2 was coated with a paint of B composition (B1, B2), and dried to obtain a flat roof material. In the figure, reference numeral 3 denotes a nail hole for fixing the flat roof material 10 to a field board or the like.

As shown in FIG. 2, the flat roofing material 10 is provided with an asphalt roofing 5 on a base plate 4 by a normal construction method, and the lower portion 2
With the upper flat roofing material 10b partially overlapping the lower flat roofing material 10a (preferably, the upper flat roofing material is applied to part of the coating film portion of the formulation B applied to the lower portion 2). The roofing work is performed in such a manner that the front ends of the members 10b are overlapped) and the roof member is shifted by half (FIG. 3a) or about 1/3 (FIG. 3b) in the lateral direction.

As for the coating, a black type paint containing A is applied to the entire surface of the flat roofing material 10 having a predetermined shape, and after drying, the lower part 2 is applied with a similar color paint containing B and dried. Alternatively, the upper portion 1 may be coated with the paint containing A, and the lower portion 2 may be coated with the paint containing B.

Further, the paints containing B include sand, silica sand,
Aggregates such as mica and iron powder may be mixed in an amount of about 10 to 30% by weight. Also, prior to painting the B-containing paint,
A moisture-curable solvent-type paint may be applied only to the lower part 2 so that the adhesion between the A-containing paint and the B-containing paint is improved, and the base material (the flat roof material body) and the coating film are coated. Adhesion can be greatly improved.

[0019]

[Table 1]

The surface of the base material (flat roofing material main body) was painted by appropriately combining the above A-containing paints (A1, A2) and B-containing paints (B1, B2). -4 and Comparative Examples 1 and 2 were prepared. The flat roof material as each test piece was constructed at an inclination angle of about 17 degrees (three-dimensional slope of the roof) as shown in FIG. After construction, water was sprinkled under the conditions shown in Table 3, and the permeation state of water was compared and observed. Table 4 shows the results.

[0021]

[Table 2]

[0022]

[Table 3]

[0023]

[Table 4]

[Consideration] As shown in the test results, when the wind speed is 30 m / sec, water reaches the nail hole in Comparative Example 1, and reaches the top of the product in Comparative Example 2. On the other hand, in Examples 1 to 3 (Example 1) or almost (Examples 2 and 3), water did not reach and there was no water leakage. That is, a coating film having a large contact angle with water (a coating film having high water repellency—paint B1,
The flat roofing material (comparative example) on which the coating film (B2) was formed,
It shows that the waterproofness is inferior to that of a coating film of the present invention (the coating film of A1 and A2) having a lower contact angle (the coating film of the present invention), which demonstrates the superiority of the present invention.

When a coating film having a large contact angle with water is formed on the non-exposed portion and a coating film having a small contact angle with water is formed on the exposed portion as in Comparative Example 2, the coating reaches the top of the product. Water has reached, and it can be seen that the conventionally known flat roofing material does not exhibit effective waterproofness during heavy rain.

In the case of the wind speed of 50 m / sec, the water reaches the nail hole in the fourth embodiment, but does not reach the uppermost part, and the one of the fourth embodiment has practically sufficient waterproofness. It can be said that.

[0027]

According to the present invention, it is possible to obtain a flat roofing material having high waterproofness even in a strong wind and rain. Further, since the area for forming the coating layer having a large contact angle with the water coating is substantially only the exposed portion, the area for applying the expensive paint is reduced, and the flat roof material can be produced at low cost. .

Further, when a large amount of extender pigment is mixed in for the purpose of lowering the contact angle of water with the coating film, the paint having a large amount of extender tends to have a porous surface, which may be an intermediate coat (for example, a wet coat). As a result, the absorption of the curable solvent paint) is increased, and an additional effect that the adhesion is further improved is also exhibited.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a flat roof material according to the present invention.

FIG. 2 is a diagram illustrating a state in which a flat roofing material is laid on a roof.

FIG. 3 is a view for explaining a flat roof material being roofed.

[Explanation of symbols]

10: flat roof material, 1: upper part (overlapping part), 2
... lower part (exposed part), 3 ... nail hole, A: coating film with small contact angle to water, B: coating film with large contact angle to water

Claims (4)

(57) [Claims] 1. A flat roofing material that is roofed in a state in which a lower one is partially overlapped with a higher one,
A coating film is formed on almost the entire surface, and that the coating film in at least almost the entire area of the overlapping portion has a smaller contact angle to water than the coating films of the other portions. Characteristic flat roof material. 2. The flat roofing material according to claim 1, wherein the coating film formed on almost the entire surface is a water-repellent coating film. 3. A paint for forming a coating film on at least almost the entire area of the overlapped portion, as compared with a coating material for forming a coating film on other portions, an extender pigment, a pigment dispersant, an emulsifier, or a thickener. 3. The flat roofing material according to claim 1, wherein at least one of the anti-settling materials is used in a paint having a large amount. 4. A paint containing at least one of a silicone-based defoaming agent or leveling agent, or an aqueous dispersion of wax as a paint for forming a coating film on the other portion. The flat roofing material according to claim 1 or 2, wherein: