JPS6133106B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for repairing an old waterproof sheet that has already been installed on a rooftop such as a flat roof.

Synthetic polymer roofing materials comply with JIS A 6008 and
As stipulated in JIS A 6009, it has been used as a rooftop waterproofing material for a long time, but waterproofing layers that have been used for more than 10 years deteriorate considerably, causing cracks, tears, or joint cracks in places, which can lead to water leakage. This will lead to an accident-prone condition. However, these various defects do not occur over the entire surface of the waterproof layer, but rather occur in areas where distortions in the building or due to thermal expansion and contraction are concentrated, so it is necessary to repair only those areas of the waterproof layer. In other words, it is possible to extend the lifespan by another 3 to 5 years.

However, the surface of an aging waterproof layer that is undergoing such deterioration is often hardened, and in the case of soft vinyl chloride waterproof sheets, the plasticizer component is volatilized and lost, resulting in a considerably rough surface. It's on the surface. Therefore, it is extremely difficult to cover and repair such surfaces with a new waterproof sheet, and as a result, the current situation is to use simple and easy repair methods such as urethane waterproofing. It was hot. However, soft vinyl chloride waterproof sheet,
In particular, when applying a urethane coating to an old PVC waterproof sheet, the physical properties are extremely different, and the adhesion and adhesion of the urethane coating to the surface of the deteriorated PVC sheet is poor. This is not a good idea and can cause the paint film to come back up again within a short period of time, causing a water leakage accident.

The present invention has been made in view of the current situation, and an example of its implementation will be described with reference to a drawing.
An amorphous linear saturated polyester resin solution 2 that has excellent permeability and is activated by heating and exhibits excellent adhesion is applied using a brush or the like, and after sufficiently drying, another new waterproof sheet 3 is applied to the area. The coated film surface and the back surface of the contact waterproof sheet are heated and softened by hot air E such as hot jet D, and at the same time, the heat-activated coated film surface and the back surface of the softened waterproof sheet are brought into contact and pressed to be thermally welded. 4. This is a method for repairing an old waterproof sheet.

The already-constructed waterproof sheet 1 in the present invention is a thermoplastic synthetic resin waterproof sheet such as a soft vinyl chloride resin or EVA type, or a vulcanized synthetic rubber sheet, and is an old and deteriorated waterproof sheet, and is used as a concrete frame A. Although the adhesive layer B is attached to the top, holes or gaps C are generated on the surface due to minute irregularities (in the form of orange skin), minute cracks (hair cracks), or tears.

The amorphous linear saturated polyester resin solution 2 used in the present invention, which has excellent permeability and exhibits excellent adhesion when activated by heating, is, for example, Byron 200 and Byron 300 manufactured by Toyobo Co., Ltd., and Sekaicho Rubber Co., Ltd. Amorphous linear saturated polyester resins such as Polyden, Biden A and Biden HI from Goodyear, Dynapol from Dynamite Nobel, Bostik Polyester from Bostik Japan Co., Ltd., Stafixx from Fuji Photo Film Co., Ltd., methylene chloride, etc. A solution dissolved in an appropriate solvent such as a chlorine-based solvent, a ketone-based solvent such as MEK, or an ester-based solvent such as ethyl acetate is used. Amorphous linear saturated polyester resins are inherently a) Adhesive to various materials such as metals, plastics, wood, and clothb Good weather resistancec Good quality stability with no change over timed Heat-activated adhesives It is.

These properties are known, and it has been used as a film adhesive by being casted on release paper or made into a film by inflation or T-die methods.

In the method of the present invention, this amorphous linear saturated polyester resin is used in the form of a solution dissolved in an appropriate solvent. This polyester solution has a low viscosity of 200 to 1,500 cps even in a 20 to 50% solution, depending on its concentration, and when applied to the wiping surface of an old waterproof sheet, it can be used to remove hair cracks or orange skin.
Penetrates evenly into deteriorated surfaces and exhibits strong paint film adhesion.

This is considered to be due to the use of linear polyester resin as the resin component. A linear polyester solution has a lower viscosity than a polyurethane resin solution at the same concentration. In particular, a solution using a chlorinated solvent such as methylene chloride has a low viscosity and has the property of penetrating into the inside of fine irregularities or hair cracks. However, polyurethane solutions do not exhibit such permeability.

This "excellent permeability" is extremely important for repairing old waterproof sheets. That is, as mentioned above, in order to firmly and permanently adhere to the deteriorated and roughened surface of an old waterproof sheet, it is necessary to form a coating film in a state where the old waterproof sheet has so-called "legs". This “legged” state is achieved by penetrating into minute irregularities and minute hair cracks. On the other hand, with adhesives such as polyurethane solutions that do not penetrate in this way, the insides of these minute irregularities and minute hair cracks become hollow, and the coating film is formed with defects on the adhesive surface, so it is not sufficient to Adhesive strength cannot be obtained.

In addition, linear saturated polyester resin can be heated to
It is activated, has excellent adhesion to other materials, and, in combination with the above-mentioned permeability, has properties that are extremely suitable as a coating film for repairing old waterproof sheets.
However, polyurethane adhesives lack these characteristics and are adhesives that simply undergo reaction curing.
The adhesive layer shows good adhesion to the new tarpaulin sheet, but the old tarpaulin sheet is in a state of ``no legs'', so peeling occurs when the adhesive layer is attached to the surface of the new tarpaulin sheet.

In addition to these linear saturated polyester resins, vinyl acetate-vinyl chloride copolymers, vinyl acetate-vinyl chloride copolymers containing carboxyl groups (e.g. vinylite VMCH resin), heat-activated acrylic resins, vinyl chloride-vinylidene chloride Resins such as copolymers have similar effects, but their adhesion and adhesive strength are low and they cannot withstand long-term use.

Amorphous linear saturated polyester resin is compatible with various thermoplastic synthetic resins, and by adding, for example, the above-mentioned VMCH, xylene resin, satucalose benzoate, etc., the thermal weldability can be further improved. The welding strength can be further improved by using a reactive urethane resin (for example, Coronate L manufactured by Dainippon Ink).

Amorphous linear saturated polyester resin, such as Vylon 200, is soluble in common solvents such as MEK, toluene, benzol, methylene chloride, and ethyl acetate, and for the purpose of the present invention, a solution with a solid content of approximately 20 to 50% is used. Used in the type of

When applying to an old waterproof sheet, first wipe off any dirt on the area with MEK, methanol, etc. before applying. Next, apply a 20-50% solution of Vylon 200 to the wiped surface with a brush.
-Apply with a target of ^about 200g/m2. The area to be coated should be slightly larger than the area of the welded part. 10-20
After drying for several minutes to completely volatilize the solvent in the solution,
A new waterproof sheet 3 cut to a regular size is placed on the coating film, and as shown in Fig. 1, with the waterproof sheet lifted up, the back side of the waterproof sheet and the surface of the coating film are heated with hot air E from a hot jet D to melt and soften. At the same time, press with a pressure roller or hand to heat weld. The heat-welded portion 4 is completely integrated, resulting in a watertight structure, and the Vylon layer exhibits excellent adhesion to the old waterproof sheet with "legs growing", and is completely heat-welded to the new waterproof sheet 3. 4
, so there is no concern that it will peel off.

Linear saturated polyester resins other than Vylon 200 can be thermally welded using almost the same method. However, it is of course necessary to select the hot jet temperature according to the type of resin used.

In addition, by utilizing the adhesion of the coating film, weld the end of the new tarpaulin sheet with the welding rod 5 to provide even more watertightness and strong welding strength between the old tarpaulin sheet and the new tarpaulin sheet. I can do it.

The amorphous linear saturated polyester resin used in the present invention exhibits excellent adhesion and adhesion to many thermoplastic synthetic resin waterproof sheets, so even if the existing old waterproof sheet is made of EVA resin. Different types of waterproof sheets, such as vinyl chloride resin sheets, can also be used as new waterproof sheets for repair, and by taking advantage of the ability to bond between different types of sheets, old synthetic rubber sheets, which were previously considered impossible, can be used. It can also be used for repair. However, when repairing an aged synthetic rubber sheet, after wiping the aged surface with a solvent,
Pretreatment such as coating with primer and applying polyester solution is required.

The first feature of the present invention is that it makes it possible to partially repair an already installed old waterproof sheet, which was previously considered impossible.

As a method for this purpose, it easily penetrates into the minute irregularities (yuzu skin) and minute hair cracks that occur on the surface of the old waterproof sheet, causing the so-called "legs to grow" on the surface of the old waterproof sheet. The point is to use an amorphous linear saturated polyester resin solution that exhibits a state of adhesion and has heat-activated adhesion that can be heat-welded to the new waterproof sheet that comes into contact with it for repair.

This characteristic allows the old waterproof sheet and the new waterproof sheet to be firmly and completely adhered to each other.

The second feature of the present invention is that hot air is used to bond an old waterproof sheet that has already been installed to a new waterproof sheet for repair. As a method for this purpose, the amorphous linear saturated polyester resin solution, which is the first feature of the present invention, is applied to the repaired area with a brush or the like in a somewhat wider area, and after sufficiently drying, a new A waterproof sheet is brought into contact, and the coated surface is brought into contact.Both sides of the back of the waterproof sheet are heated by blowing hot air from a hot jet, etc., and the heat-activated coating surface and the heat-softened back surface of the waterproof sheet are brought into contact.・Press to complete the adhesion between the two.

This method has no limitations on pot life or adhesion time like conventional reaction-curing polyurethane adhesives, and eliminates the fogging phenomenon (open time) on the adhesive surface that occurs with ordinary solution-based adhesives. There is no phenomenon in which water condenses on the surface of the adhesive due to the cooling phenomenon caused by solvent volatilization during the adhesive process, and there is no need for double-sided coating as is the case with contact-type rubber adhesives. In addition, bonding can be completed by simply pressing the two together after heating with hot air, which has the advantage that it is extremely simple and can be carried out at any temperature.

The third feature of the present invention is that it is possible to bond an already installed old waterproof sheet to a new waterproof sheet to be repaired and abutted even if they are different types of resin sheets. For example, if the existing waterproof sheet is an EVA-based resin sheet, and the deteriorated parts are due to wear and tear caused by people walking, it may be possible to use a PVC sheet, which has better abrasion resistance than the EVA-based resin sheet. Even in such cases, the amorphous linear saturated polyester resin coating has excellent adhesion to both of these, so it can be easily coated using the methods described in the first and second characteristics. Moreover, it is possible to adhere completely.

It is surprising that this adhesion between different materials is also possible between an aged synthetic rubber sheet and a thermoplastic synthetic resin waterproof sheet.

The fourth feature of the present invention is that after a new contact tarpaulin sheet is adhered onto the old tarpaulin sheet, the ends of the new tarpaulin sheet are welded using a welding rod to obtain even more watertightness. It is possible to do this. This is because the amorphous linear saturated polyester resin solution is applied to the repaired area somewhat widely, so even if a new waterproof sheet is applied, the amorphous Since the linear saturated polyester resin coating layer is present, the welding rod is firmly bonded to the coating layer and at the same time is melted and bonded to the abutting waterproof sheet layer. This is completely unthinkable with conventional methods using adhesives, and is only possible with the method of the present invention.

[Brief explanation of the drawing]

The drawings show an example of the implementation of the method of repairing an old waterproof sheet according to the present invention, and FIG. 1 is a cross-sectional view of a state in which heat welding has been performed, and FIG. 2 is a cross-sectional view of a state before heat welding. Middle 1 is old waterproof sheet, 2 is painted surface,
3 is the new waterproof sheet in contact, 4 is the heat welded part, E
is hot air.

Claims (1)

[Claims] 1. After wiping the surface of the repaired part of the existing old waterproof sheet using an appropriate solvent, apply an amorphous substance with excellent permeability and excellent adhesion to the wiped surface to some extent and activated by heating. After applying a linear saturated polyester resin solution using a brush or the like and drying thoroughly, another new waterproof sheet is brought into contact with the area, and hot air such as hot jet is blown on the coated surface and the back side of the contact waterproof sheet. A method for repairing an old waterproof sheet, which is characterized in that the surface of the heat-activated coating film and the back surface of the softened waterproof sheet are brought into contact and pressed together to heat-weld them.