JPS5950391B2 - Method of applying mortar to polyurethane resin waterproof layer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of applying mortar to a waterproof layer of a polyurethane resin coating.

In recent years, polyurethane resin coating waterproofing materials have been widely used for rooftop waterproofing, balconies, washrooms, toilets, basements, bathrooms, wall surfaces, etc. due to their excellent rubber elasticity, workability, water resistance, and durability. ing.

When used for these purposes, polyurethane resin-based waterproof coatings have rarely been used as a finished surface layer, and generally mortar is placed on the surface of the waterproof coating. and further tiling as necessary.

However, the adhesion between the waterproof polyurethane resin coating layer and the mortar is usually poor, and the two do not actually adhere to each other, forming a so-called floating structure. The placed mortar is prone to cracking and eventually causes complete peeling.

Such cracks are likely to occur, for example, at corners where a vertical surface and a horizontal surface are in contact with each other, such as on a balcony, and seriously impair the appearance. On the other hand, if the adhesion between the polyurethane resin waterproof coating layer and the mortar is very strong, this is not preferable since the polyurethane resin coating waterproof layer will break due to the difference in thermal expansion coefficient and strength difference between the two.

In view of these circumstances, the present inventors have conducted various studies and found that after the polyurethane resin coating waterproofing material is semi-cured or hardened, a polyurethane resin coating material is applied to the polyurethane resin coating waterproofing layer, The nonwoven fabric is crimped while it is uncured, and after the polyurethane resin coating material has hardened, an emulsion such as polyethylene vinyl acetate copolymer emulsion is further applied, and after drying and film formation, mortar is applied. The present inventors have discovered that it is possible to prevent the occurrence of such cracks in mortar, and have completed the present invention.

That is, the present invention provides a method for applying mortar to a polyurethane resin waterproof coating layer, in which a semi-cured or hardened waterproof layer formed by applying a polyurethane resin coating waterproofing material is subjected to 1) curing with respect to the waterproof layer; The adhesive strength after is 2, Okg/'
2) applying a nonwoven fabric to the uncured layer of the coating material; and 3) applying at least one radically polymerizable ethylenic material to the layer formed by curing the coating material. Applying an emulsion obtained by emulsion polymerization of an unsaturated monomer, drying it to form a film, and (4) applying mortar to the formed film. The present invention provides a method for coating.

The present invention will be explained in detail below.

The polyurethane resin coating film waterproofing material used in the method of the present invention is a normal polyurethane paint used as a waterproofing material, and can be either a two-component type (two-component type) or a one-component type (one-component type). include.

Two-component coating film waterproofing materials consist of an isocyanate prepolymer (usually referred to as the base agent) and a crosslinking agent such as aromatic amine and/or polyol as a hardening agent, and the base agent and hardener are mixed at the construction site and applied. It is constructed on the surface. mosquito·
Two-component coating waterproofing materials are usually divided into the following three types based on their formulation.

1. Tar urethane waterproofing material containing anhydrous tar as a filler 2. Non-tar urethane waterproofing material that does not use anhydrous tar 3. Modification/filling material containing a colorless inorganic filler and pigment, polyol crosslinking or amine crosslinking or Colored urethane waterproofing material that crosslinks both.

When carrying out the method of the present invention, any type of these materials may be used, such as the commercially available Cosmo Flex 3x R-1.
0, Cosmoflex R-10N (all manufactured by Sumitomo Chemical Co., Ltd.), etc. are used.

Furthermore, oil-denatured type, moisture curing type, and block type waterproofing materials are known as one-component urethane resin coating waterproofing materials, and any of these waterproofing materials can be used in the method of the present invention. Moisture-curing waterproofing materials with low isocyanate content are preferably used.

There are particular restrictions on the polyurethane resin coating material used in the method of the present invention, as long as it has an adhesive strength of 2.0 kg/CIn2 or more after curing to the polyurethane resin coating waterproof layer. Although the material can be appropriately selected from the above-mentioned polyurethane resin-based coating film waterproofing materials, moisture-curable urethane resin-based primers (or sealers) are preferred.

For example, commercially available Cosmo Prime C (manufactured by Sumitomo Chemical Co., Ltd.) is suitably used. The adhesive strength of the polyurethane resin coating material to the polyurethane resin coating waterproof layer after curing is an essential element for the present invention.
If CIn is less than 2, peeling easily occurs and the object of the present invention cannot be achieved.

The polyurethane resin coating material is applied at a rate of 50 to 600 g/m after semi-curing or curing to the extent that the polyurethane resin coating waterproofing material can withstand pressure bonding of the nonwoven fabric.

In this case, if the coating amount of the coating material is less than 50 g/m2, sufficient adhesion of the nonwoven fabric cannot be obtained, and if it exceeds 600 g/m2, the nonwoven fabric will be completely buried in the polyurethane resin coating material, so it is preferable. do not have. The nonwoven fabric is pressed onto the polyurethane resin coating material when the polyurethane resin coating material is in an uncured state and preferably has a viscosity in the range of 5000 Cps to 100,000 CPS.

The nonwoven fabric used in the present invention may be either inorganic or organic, but one with excellent physical strength, water resistance, and alkali resistance is preferred. Examples of the emulsion obtained by emulsion polymerization of at least one radically polymerizable ethylenically unsaturated monomer used in the present invention include polyethylene vinyl acetate copolymer emulsion, polyvinyl chloride emulsion, polyacrylic emulsion, etc. be done.

Additives such as stabilizers may be added to these emulsions as necessary.

The coating amount of the emulsion is usually preferably 50 to 600 g/M2; if it is less than 50 g/M2, the emulsion layer will be thin and its effect will not be fully exhibited, and if it exceeds 600 g/M2, the nonwoven fabric will is buried in the film-forming layer of the emulsion, rendering the use of non-woven fabric meaningless and slowing dry film-forming, making it uneconomical.Although it varies somewhat depending on the amount of absorption into the non-woven fabric, it is 100 to 400 g/M2.
The coating amount is more preferable.

The purpose of using the emulsion composition in the present invention is to significantly improve the adhesion of mortar to the nonwoven fabric, and to form a film-forming layer of the emulsion composition inside the nonwoven fabric. The method of the present invention will be explained in detail below with reference to the drawings.

FIG. 1 shows a construction cross section according to the method of the present invention, and 1 indicates the base (surface to be coated). A polyurethane resin coating film waterproofing material is applied to this base 1 by a conventional method to form a waterproof layer 2. After the waterproof layer 2 is semi-cured or hardened, a polyurethane resin coating material is applied by a conventional method to form the layer 3. The nonwoven fabric 4 is pressed onto the uncured layer 3 as soon as possible after applying the coating material. The nonwoven fabric 4 may be crimped by any conventional means known to those skilled in the art, such as by using a roller or the like. After the layer 3 is cured, an emulsion is further applied and dried to form an emulsion film forming layer 5, and then a mortar 6 is applied to form an integral structure with the nonwoven fabric. The most distinctive feature of the present invention is the use of nonwoven fabric and the formation of an emulsion film layer.

In other words, since the constituent fibers of the nonwoven fabric are arranged randomly,
The adhesion between the polyurethane resin coating waterproof layer and the mortar is achieved by having one side of the nonwoven fabric embedded in the polyurethane resin coating material and the other side being integrated with the mortar, creating a strong adhesion between the polyurethane resin coating waterproof layer and the mortar. At the same time, the shrinkage stress between the two is buffered by the emulsion film layer inside the nonwoven fabric. The present invention will be explained below using examples.

Example 1 Commercially available Cosmoflex R-10 [(for horizontal surfaces) two-component polyurethane resin system] was applied as a polyurethane resin coating film waterproofing material to a spread of 30 cm in width centered on the corner where the vertical surface and the horizontal surface touch. , Sumitomo Chemical Co., Ltd. product] and Cosmoflex R-ION [(sag prevention type for vertical surfaces) two-component polyurethane resin system, Sumitomo Chemical Co., Ltd. product] were applied to a thickness of 2 mm on each of the horizontal and vertical surfaces. Hardening and curing was performed.

After that, 100% of the moisture-curing urethane resin coating material Cosmo Prime C- (Sumitomo Chemical Co., Ltd. product 1, resin content 35%) was applied.
g/M2 and directly coated with non-woven fabric #EC-200.
- Kurashiki Textile Processing Co., Ltd. product) was crimped with a roller.

After 60 minutes, the urethane resin coating material Cosmo Prime C was cured with a portion of the nonwoven fabric embedded in the urethane resin coating material Cosmo Prime C.

As an emulsion component, Sumikaflex #400
(Ethylene vinegar beer emulsion - Sumitomo Chemical Co., Ltd. - Solid content 5
5%) was applied at 300 g/m.

After 20 minutes, cement mortar was applied to a thickness of 1 cm using a metal trowel.

The resulting structure was exposed outdoors, but no abnormalities such as cracks or delamination were observed even after 4 months.

Further, when the adhesive strength was measured, an adhesive strength of 6.5 kg/Cm was obtained.

Comparative Example 1 In Example 1, when the structure obtained by applying cement mortar directly to the hardened surface of the polyurethane resin coating waterproofing material was exposed outdoors, after one month, the area where the vertical and horizontal surfaces touched Cracks occurred, and after four months, part of the mortar broke and peeled.

[Brief explanation of the drawing]

Fig. 1 shows a construction cross section according to the method of the present invention, in which 1 is the base material (coated surface), 2 is the polyurethane resin coating waterproof layer, 3 is the polyurethane resin coating material layer, and 4 is the nonwoven fabric layer. , 5 indicates an emulsion film-forming layer, and 6 indicates a mortar layer.

Claims (1)

[Claims] 1 In the method of applying mortar to a polyurethane resin waterproof coating layer, the semi-cured or hardened waterproof layer formed by applying the polyurethane resin coating waterproofing material has 1) adhesive strength after curing to the waterproof layer. A polyurethane resin-based coating material having a thickness of 2.0 kg/cm^2 or more is applied, 2) a nonwoven fabric is pressed onto the uncured layer of the coating material, and 3) at least A polyurethane resin system characterized by applying an emulsion obtained by emulsion polymerization of a type of radically polymerizable ethylenically unsaturated monomer, drying it, forming a film, and then applying mortar to the formed film. How to apply mortar to the waterproof layer of the paint film