Restoration paints and restoration methods

Abstract

To provide a restoration paint capable of forming a repair layer with an excellent appearance without forming an uneven pattern on the surface of the repair layer when forming a repair layer on the surface of a polyvinyl chloride waterproof sheet that has deteriorated over time due to the volatilization of the plasticizer, and a restoration construction method of forming a repair layer with excellent appearance over the surface of a polyvinyl chloride waterproof sheet that has deteriorated over time by using the restoration paint.SOLUTION: A disclosed restoration paint is used for forming a restoration layer over the surface of a polyvinyl chloride waterproof sheet that has deteriorated over time by drying after feeding the same. The restoration paint contains a resin material, a plasticizer, a filler, water, and a thickener. An emulsion that contains the resin material and water is formed in the restoration paint.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a restoration coating material used to form a restoration layer on the surface of a polyvinyl chloride waterproof sheet that has deteriorated over time, and a restoration application method. [Background technology]

[0002] In recent years, with the demand for buildings to be more durable, sheet waterproofing structures in which polyvinyl chloride waterproof sheets are laid and constructed have been adopted on the rooftops, balconies, etc. of many buildings (see, for example, Patent Document 1).

[0003] In this sheet waterproofing structure, for example, a steel plate (placement component) formed to correspond to the shape of the boundary between the rooftop floor and a wall section erected along the outer edge of the floor is placed, and at least a portion of the steel plate, the floor section, and the wall section are covered with a polyvinyl chloride-based waterproof sheet (hereinafter sometimes simply referred to as a "waterproof sheet") containing a vinyl chloride resin and a plasticizer, thereby waterproofing the rooftop.

[0004] In this sheet waterproofing structure, as time passes after construction, the plasticizer evaporates from the waterproof sheet due to exposure to sunlight and rainwater (muddy water), resulting in a decrease in the flexibility of the waterproof sheet. This causes stress in the waterproof sheet, which can cause cracks in the waterproof sheet and prevent it from achieving a high level of waterproofing.

[0005] The occurrence of cracks in this waterproof sheet is due to the evaporation of plasticizer from the waterproof sheet, so for example, Patent Document 2 proposes applying a repair paint containing an emulsion and a plasticizer to the surface of the waterproof sheet and then drying it to form a repair layer (film formation).

[0006] By forming a repair layer on the waterproof sheet using the repair paint in this way, the plasticizer derived from the repair paint is contained in the repair layer, and the plasticizer can be migrated (diffused) into the waterproof sheet. Therefore, the flexibility of the waterproof sheet can be restored to excellent levels. As a result, the generation of stress in the waterproof sheet can be eliminated, and the occurrence of cracks in the waterproof sheet can be accurately prevented or suppressed.

[0007] However, in the repair layer formed using the repair paint described in Patent Document 2, an uneven pattern with multiple deep vertical grooves like the bark of a cedar tree is formed on the surface, resulting in a poor appearance of the waterproof sheet on which the repair layer is formed.

[0008] Therefore, the formation of a repair layer on a waterproof sheet using such a repair paint is almost limited to sheet waterproof structures applied to buildings that are rarely seen by the public, such as the rooftops of government buildings, and there has been a problem that it tends to be avoided in sheet waterproof structures applied to balconies of ordinary houses, which are often seen by the public. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2007-070877 A [Patent Document 2] JP 2005-021868 A Summary of the Invention [Problem to be solved by the invention]

[0010] The object of the present invention is to provide a repair paint that, when forming a repair layer on the surface of a polyvinyl chloride-based waterproof sheet that has deteriorated over time due to the volatilization of plasticizer, can provide a repair layer with excellent appearance without forming an uneven pattern on the surface of the repair layer, and a repair construction method that uses such repair paint to form a repair layer with excellent appearance on the surface of a polyvinyl chloride-based waterproof sheet that has deteriorated over time. [Means for solving the problem]

[0011] Such an object can be achieved by the present invention described in (1) to (10) below. (1) A restoration paint used to form a restoration layer on the surface of a polyvinyl chloride waterproof sheet that has deteriorated over time by applying it and then drying it. The repair paint contains a resin material, a plasticizer, a filler, water, and a thickener, and the repair paint forms an emulsion containing the resin material and the water, The ratio of the content of the plasticizer to the total weight of the repair paint is 15% by weight or more and 30% by weight or less; The ratio of the content of the filler to the total weight of the repair paint is 15 .7 % or more by weight and 22% or less by weight.

[0012] (2) The repair paint according to the above (1), wherein the resin material is at least one of an ethylene-vinyl acetate copolymer resin, an acrylic resin, and a vinyl chloride resin.

[0013] (3) A restoration paint according to the above (1) or (2), wherein the thickener is an associative thickener.

[0014] (4) The repair paint according to any one of (1) to (3) above, further comprising a surfactant.

[0015] (5) A repair paint according to any one of (1) to (4) above, wherein the thickener content is 0.3% by weight or more and 2.0% by weight or less.

[0016] (6) A repair paint according to any one of (1) to (5) above, wherein the water content is from 26% by weight to 33% by weight.

[0017] (7) The filler is Contains hollow silica A restoration paint according to any one of (1) to (6) above.

[0018] (8) A restoration paint according to any one of (1) to (7) above, having a viscosity at 23°C of 1000 mPa·s or more and 6000 mPa·s or less.

[0019] (9) A repair paint according to any one of (1) to (8) above, which is applied to the surface of the polyvinyl chloride waterproof sheet by using a roller brush.

[0020] (10) A repair construction method, characterized in that the repair paint described in any one of (1) to (9) above is applied to the surface of the polyvinyl chloride waterproof sheet that has deteriorated over time, and then dried to form the repair layer. Effect of the Invention

[0021] According to the present invention, when a repair layer is formed using a repair paint on the surface of a polyvinyl chloride waterproof sheet that has been deteriorated over time due to the volatilization of a plasticizer, which is included in a sheet waterproof structure, it is possible to appropriately suppress or prevent the formation of an uneven pattern on the surface of the repair layer, thereby making it possible to form a repair layer with excellent appearance on the surface of the polyvinyl chloride waterproof sheet.

[0022] Therefore, the formation of a repair layer using such a repair paint on a polyvinyl chloride waterproof sheet is not limited to sheet waterproof structures applied to buildings that are rarely seen by the public, such as the rooftops of government buildings, but can also be widely applied to sheet waterproof structures applied to balconies of ordinary houses that are often seen by the public. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The restoration paint and restoration method of the present invention will be described in detail below based on preferred embodiments.

[0024] The repair paint of the present invention is used to form a repair layer by applying it to the surface of a polyvinyl chloride waterproof sheet that has deteriorated over time and then drying it, and is characterized in that it contains a resin material, a plasticizer, a filler, water, and a thickener, and that the repair paint forms an emulsion containing the resin material and the water.

[0025] Here, the polyvinyl chloride waterproof sheet on which the repair layer derived from the repair paint of the present invention is formed is provided in a sheet waterproof structure installed on the rooftop or balcony of a building.

[0026] This sheet waterproofing structure comprises a steel plate (placement component) coated with polyvinyl chloride resin that is positioned at the boundary between the floor of a rooftop, balcony, etc. and a wall section that is erected along the outer edge of the floor section, in a manner that corresponds to the shape of the boundary section, and a polyvinyl chloride waterproof sheet (hereinafter sometimes simply referred to as a "waterproof sheet") containing polyvinyl chloride resin and a plasticizer that covers at least a part of the steel plate, the floor section, and the wall section, thereby forming a structure that provides waterproofing to rooftops, verandas, etc.

[0027] In a sheet waterproof structure having such a configuration, when the waterproof sheet is exposed to sunlight or rainwater (muddy water), the plasticizer contained in the waterproof sheet will volatilize, which may result in cracks in the waterproof sheet and deterioration over time that prevents the sheet from providing a high level of waterproofing.

[0028] By applying the repair coating of the present invention to the surface of the waterproof sheet that has deteriorated over time and then drying it, a repair layer containing a plasticizer is formed, and the plasticizer can be transferred (diffused) from this repair layer to the waterproof sheet. This allows the flexibility of the waterproof sheet to be restored to an excellent state, and the waterproof sheet and the sheet waterproof structure can be repaired.

[0029] In addition, the repair paint of the present invention contains a resin material, a plasticizer, a filler, water, and a thickener, and forms an emulsion containing the resin material and water in the repair paint. Even if the emulsion is formed, the viscosity of the repair paint is set within an appropriate range by including a thickener. Therefore, when a repair layer is formed on the surface of a waterproof sheet using the repair paint of the present invention, the formation of an uneven pattern on the surface of the repair layer can be appropriately suppressed or prevented. As a result, a repair layer with excellent appearance is formed on the surface of the waterproof sheet.

[0030] Therefore, the formation of a repair layer using such a repair paint on a polyvinyl chloride waterproof sheet is not limited to sheet waterproof structures applied to buildings that are rarely seen by the public, such as the rooftops of government buildings, but can also be widely applied to sheet waterproof structures applied to balconies of ordinary houses that are often seen by the public.

[0031] <Restoration paint> In this embodiment, the repair paint contains a resin material, a plasticizer, a filler, water, a thickener, and a surfactant. Each of the components constituting the repair paint will be described in detail below.

[0032] The resin material is included as the main material of the repair paint, and it maintains the shape of the repair layer that is formed by drying the repair paint, and also functions as a base for supplying plasticizer from the repair layer to the waterproof sheet that has deteriorated over time.

[0033] The resin material is not particularly limited, but for example, ethylene vinyl acetate copolymer resin (EVA resin), acrylic resin, vinyl chloride resin, etc. are preferably used, and one or more of these can be used in combination. That is, one type of polymer alone or a mixture of two or more types of polymers can be used.

[0034] Examples of EVA-based resins include copolymers containing ethylene and vinyl acetate, and copolymers containing ethylene, vinyl acetate, and other monomers such as vinyl chloride and propylene.

[0035] The acrylic resin may be, for example, a polymerized acrylic polymerizable component. The acrylic polymerizable component may be at least one of acrylic acid, acrylic acid derivatives, methacrylic acid, and methacrylic acid derivatives.

[0036] Examples of the acrylic acid derivatives include acrylic acid esters, acrylamides, and acrylonitrile, and examples of the methacrylic acid derivatives include methacrylic acid esters, methacrylamides, and methacrylonitrile.

[0037] Examples of vinyl chloride resins include monomeric polymers of vinyl chloride, and copolymers of vinyl chloride with vinyl acetate, ethylene, propylene, or the like.

[0038] By using these materials as the resin material, the plasticizer contained in the repair layer can be reliably transferred to the waterproof sheet.

[0039] The plasticizer is contained in the repair layer, i.e., the repair paint, in order to improve the flexibility of the waterproof sheet that has deteriorated over time by migrating from the repair layer formed using the repair paint to the waterproof sheet.

[0040] The plasticizer is not particularly limited, but examples thereof include phthalate ester plasticizers such as DOP (dioctyl phthalate), DBP (dibutyl phthalate), DIBP (diisobutyl phthalate), and DHP (diheptyl phthalate), aliphatic dibasic acid ester plasticizers such as DOA (di-2-ethylhexyl adipate), DIDA (diisodecyl adipate), and DOS (di-2-ethylhexyl sebacate), aromatic carboxylate ester plasticizers such as ethylene glycol benzoates, and trimellitic acid ester plasticizers such as TOTM (trioctyl trimellitate), and the like, and one or more of these can be used in combination. By using these as plasticizers, when the plasticizer migrates from the repair layer to the waterproof sheet, the flexibility of the waterproof sheet that has deteriorated over time can be reliably improved again.

[0041] The content of the plasticizer is, for example, preferably 15% by weight to 30% by weight, more preferably 22% by weight to 26% by weight, based on the total weight of the repair paint, which allows a sufficient amount of plasticizer to migrate from the repair layer formed using the repair paint to the waterproof sheet.

[0042] The filler is included in the repair layer, i.e., the repair paint, to keep the plasticizer in the repair layer formed using the repair paint without the plasticizer prematurely migrating to the waterproof sheet.

[0043] The filler is not particularly limited, but examples thereof include titanium oxide, clay, silica, calcium carbonate, barium sulfate, silica sand, talc, etc., and one or more of these can be used in combination. Among them, titanium oxide, silica, silica sand, and talc are preferable. By using titanium oxide as a filler, in addition to the above function, the weather resistance of the repair layer can be improved. In addition to the above function, by using silica, the antifouling property of the repair layer can be improved. Furthermore, by using silicate compounds such as silica sand and talc, in addition to the above function, the occurrence of cracks in the repair layer can be appropriately suppressed or prevented.

[0044] The content of the filler is preferably, for example, 15% by weight or more and 25% by weight or less based on the total weight of the repair coating material, which allows the filler to reliably exhibit its function as a filler in the repair layer.

[0045] Water is contained in the repair paint in a sufficient amount to form an emulsion containing at least water and a resin material, and to appropriately suppress or prevent the formation of an uneven pattern having multiple deep vertical grooves, like the bark of a cedar tree, on the surface of the repair layer formed using the repair paint.

[0046] The water content is, for example, preferably 26% by weight to 33% by weight, more preferably 26% by weight to 31% by weight, based on the total weight of the restoration paint. If the water content is less than the lower limit, depending on the type of resin material contained in the restoration paint, it may be difficult to form an emulsion containing at least water and a resin material in the restoration paint. If the water content exceeds the upper limit, depending on the type of thickener contained in the restoration paint, the viscosity of the restoration paint may be too low, making it impossible to form a restoration layer with the desired thickness on the waterproof sheet.

[0047] The thickener is contained in the repair layer, i.e., the repair paint, to increase the viscosity of the repair paint and to accurately suppress or prevent the formation of an uneven pattern in the repair layer formed using the repair paint, so that a repair layer of the desired thickness can be formed on the waterproof sheet even if the repair paint contains a sufficient amount of water.

[0048] The thickener is not particularly limited, but examples thereof include association type thickeners that have at least one hydrophilic part and one hydrophobic part in one molecule, and that exhibit a thickening effect by adsorbing the hydrophobic part to the surface of emulsion particles in water, inorganic thickeners such as silicate, metal silicate, and colloidal alumina, polyacrylic acid thickeners such as copolymers of (meth)acrylic acid and (meth)acrylic acid ester, cellulose derivative thickeners such as carboxymethylcellulose, and protein thickeners such as casein and sodium caseinate, and can be used alone or in combination of two or more of these, and among them, association type thickeners are preferable. If the association type thickener is used, the viscosity of the repair paint forming the emulsion can be reliably increased.

[0049] As described above, the associative thickener may have at least one hydrophilic portion and one hydrophobic portion in one molecule, but it is preferable that the associative thickener has a hydrophobic portion at both ends and a hydrophilic portion located therebetween. This allows the hydrophobic portions at both ends to associate with the hydrophobic portion of the emulsion, thereby connecting the two emulsions via the associative thickener, and as a result, a loose network structure is formed in the entire repair paint, thereby increasing the viscosity of the repair paint.

[0050] The associative thickener is not particularly limited, but examples thereof include urethane associative thickeners having hydrophobic groups at both ends and a hydrophilic portion containing a urethane bond in the molecular chain, polycarboxylic acid associative thickeners, polyacrylic acid associative thickeners such as sodium polyacrylate, polyvinyl thickeners such as polyvinyl alcohol and polyvinyl benzyl ether copolymers, and polyether associative thickeners such as polyether dialkyl esters and polyether dialkyl ethers.

[0051] The weight average molecular weight (Mw) of the associative thickener is, for example, preferably 1,000 or more and 200,000 or less, and more preferably 2,000 or more and 150,000 or less.

[0052] The content of the thickener is, for example, preferably 0.3% by weight or more and 2.0% by weight or less, more preferably 0.5% by weight or more and 1.5% by weight or less, based on the total weight of the repair paint. This allows the repair paint to reliably function as a thickener. Therefore, in order to appropriately suppress or prevent the formation of a concave-convex pattern in the repair layer formed using the repair paint, even if the repair paint contains a sufficient amount of water, the viscosity of the repair paint can be increased to form a repair layer having a desired thickness on the waterproof sheet.

[0053] The surfactant is contained in the repair paint in order to function as an emulsifier for forming an emulsion containing at least the resin material and water in the repair paint.

[0054] The surfactant is not particularly limited, but examples thereof include anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc. By including such a surfactant in the repair paint, it is possible to reliably form an emulsion containing at least the resin material and water in the repair paint.

[0055] In addition, in the case where an emulsion containing a resin material and water can be formed in the repair paint even in the absence of a surfactant, the addition of a surfactant to the repair paint can be omitted.

[0056] In addition to the resin materials described above, the repair paint may contain dispersants, antifreeze agents, antifoaming agents, film-forming aids, stabilizers, stabilization aids, ultraviolet absorbers, flame retardants, fiber reinforcing agents, colorants, lubricants, etc.

[0057] Here, in the present invention, in consideration of the safety of the installer and others when forming the repair layer, an emulsion containing at least a resin material and water is formed without containing organic solvents in the repair paint, thereby ensuring the film-forming ability of the repair layer on the waterproof sheet using the repair paint.

[0058] The method for forming a repair layer on a waterproof sheet using a repair paint (the repair application method of the present invention) will be described below.

[0059] [1] First, wash the surface of the waterproof sheet that has deteriorated over time with water using a brush or other tool, then dry it.

[0060] [2] Next, a repair paint is applied onto the waterproof sheet and then dried, forming a repair layer on the waterproof sheet, i.e., on the surface of the waterproof sheet.

[0061] When this repair paint is applied and dried, an emulsion is formed in the repair paint, and since this emulsion is dispersed almost uniformly in the repair paint, a repair layer with an almost uniform thickness can be formed over the entire waterproof sheet.

[0062] As described above, the present invention improves the safety of workers when forming a repair layer because the repair paint does not contain organic solvents. The repair layer can be formed simply by supplying and drying the repair paint containing the emulsion, making the application easy and easy to work with, and allowing efficient repair and application to sheet waterproofing structures.

[0063] The method of supplying the repair paint to the surface of the waterproof sheet is not particularly limited, and examples thereof include a method of applying the paint with a roller brush and a spraying method, among which the method of applying the paint with a roller brush is preferred. By using a roller brush, a repair layer formed to a uniform thickness can be relatively easily formed on the waterproof sheet. Furthermore, in the present invention, the repair paint contains a sufficient amount of water. Therefore, even if a roller brush is used as a supply method, it is possible to appropriately suppress or prevent the formation of an uneven pattern having a plurality of deep vertical grooves, such as the bark of a cedar tree, on the surface of the repair layer to be formed.

[0064] The amount of the repair paint applied to the surface of the waterproof sheet is preferably 200 g / m 2 More than 1800g / m 2 Less than 300 g / m 2 More than 1500g / m 2 The thickness of the repair coating is set as follows. This makes it possible to reliably form a repair layer on the surface of the waterproof sheet with a thickness that allows a sufficient amount of plasticizer to be supplied to the waterproof sheet. In other words, by appropriately setting the amount of repair coating material supplied to the surface of the waterproof sheet, a repair layer with a desired thickness can be formed.

[0065] Furthermore, in the present invention, the repair paint contains a thickener, which suppresses the viscosity of the repair paint from decreasing even if the repair paint contains a sufficient amount of water. Therefore, even if the waterproof sheet of the sheet waterproofing structure is placed on a slope that is inclined for drainage and the repair paint is supplied to the surface of the waterproof sheet in the above-mentioned supply amount, the supplied repair paint can be appropriately suppressed or prevented from flowing down the slope and being unevenly distributed on the waterproof sheet placed on the slope. Therefore, a repair layer with a thickness that can supply a sufficient amount of plasticizer to the waterproof sheet can be reliably formed with a substantially uniform thickness on the surface of the waterproof sheet.

[0066] Specifically, the viscosity (23°C) of such a repair paint is preferably set to 1000 mPa·s or more and 6000 mPa·s or less, more preferably 2000 mPa·s or more and 4100 mPa·s or less. This appropriately suppresses or prevents the formation of an uneven pattern on the surface of the repair paint, and also ensures the formation of a repair layer on the surface of the waterproof sheet that has a thickness that allows a sufficient amount of plasticizer to be supplied to the waterproof sheet.

[0067] Although the restoration paint and restoration application method of the present invention have been described above, the present invention is not limited thereto.

[0068] For example, in the repair coating of the present invention, each of the constituent materials contained therein can be replaced with any other material capable of exerting a similar function, or any other constituent material can be added.

[0069] In addition, in the repair construction method of the present invention, a process before process [1], an intermediate process between processes [1] and [2], or a process after process [2] may be added for any purpose. EXAMPLES

[0070] The present invention will be described in more detail below with reference to examples, although the present invention is not limited to these examples in any way.

[0071] 1. Preparation of raw materials First, the raw materials used for preparing the repair paints of the examples and comparative examples are as follows.

[0072] <Aqueous emulsion of EVA resin> EVA emulsion 1 (manufactured by Sumitomo Chemical Co., Ltd., "Sumika Flex S-510HQ", non-volatile component 55% by weight, viscosity 400 mPa·s) EVA emulsion 2 (manufactured by Sumitomo Chemical Co., Ltd., "Sumika Flex S-400HQ", non-volatile component 55% by weight, viscosity 1000 mPa·s)

[0073] <Plasticizer> Plasticizer 1 (DINP, manufactured by Jay Plus Co., Ltd.)

[0074] <Surfactant> Surfactant 1 (alkylolamine salt, manufactured by BYK Co., Ltd., "DISPERBYK-180")

[0075] <Filler> Titanium oxide (manufactured by Ishihara Sangyo Co., Ltd., "CR-super70", average particle size 0.25 μm) Hollow silica (manufactured by Hebei Baisite Technology Co., Ltd., "SA", average particle size 90 μm)

[0076] <Water> Purified water (manufactured by Furukawa Pharmaceutical Co., Ltd.)

[0077] <Thickener> Associative thickener (polyurethane compound, manufactured by BYK Co., Ltd., "RHEOBYK-M2600VF")

[0078] 2. Preparation of repair paints [Example 1] 100 parts by weight of EVA emulsion 1, 45 parts by weight of plasticizer 1, 9 parts by weight of titanium oxide, 22 parts by weight of hollow silica, 1.8 parts by weight of surfactant 1, 6.8 parts by weight of purified water, and 2.3 parts by weight of associative thickener were prepared, and then these were uniformly mixed at 25°C using a mixer to prepare the repair paint of Example 1.

[0079] The viscosity (23° C.) of the restoration coating material of Example 1 was measured using a BH type rotational viscometer (Tokimec Corporation) and was found to be 2400 mPa·s.

[0080] [Examples 2 to 12, Comparative Examples 1 and 2] The restoration paints of Examples 2 to 12 and Comparative Examples 1 and 2 were prepared in the same manner as in Example 1, except that the types of raw materials used in preparing the restoration paints and their contents were changed as shown in Table 1.

[0081] 3. Evaluation 3-1. Surface properties of the repair layer The surface of a soft polyvinyl chloride waterproof sheet with an average thickness of 1.3 mm was washed with water using a brush and then dried. Thereafter, at room temperature (23°C), 400 g / m of the repair paint of each Example and Comparative Example was applied to the surface of the waterproof sheet using a roller brush. 2 After forming a coating film by applying the coating amount of 100g / m2, the coating film was dried to form a repair layer on the surface of the waterproof sheet.

[0082] The surface properties of the repair layers formed using the repair paints of each Example and Comparative Example were then visually observed, and evaluated based on the observation results using the following criteria.

[0083] <Judgment criteria> ◎: No uneven pattern is observed on the surface of the repair layer, and a very smooth surface is formed. ○: Although some vertical grooves are observed on the surface of the repair layer, the surface can be said to be smooth. ×: An uneven pattern having multiple deep vertical grooves is formed on the surface of the repair layer.

[0084] 3-2. Flowability of repair paint on slopes The surface of a soft polyvinyl chloride waterproof sheet with an average thickness of 1.3 mm was washed with water using a brush and then dried. Thereafter, the waterproof sheet was placed on an inclined surface at an inclination angle of 15°, and 400 g / m of the repair paint of each Example and Comparative Example was applied to the surface of the waterproof sheet using a roller brush at room temperature (23°C). 2 After forming a coating film by applying the coating amount of 100g / m2, the coating film was dried to form a repair layer on the surface of the waterproof sheet.

[0085] Then, the repair layers formed using the repair paints of each Example and Comparative Example were visually observed for the presence or absence of uneven distribution on the downstream side of the slope due to the repair paint (coating film) flowing down the slope, and were evaluated based on the observation results using the following judgment criteria.

[0086] <Judgment criteria> ◎: No uneven distribution of the repair layer on the downstream side was observed. A repair layer of uniform thickness is formed. ○: Although some uneven distribution on the downstream side of the repaired layer is observed, It can be said that a repair layer with a nearly uniform thickness has been formed. ×: Clear uneven distribution of the repair layer on the downstream side was observed. It was not possible to form a repair layer with a uniform thickness.

[0087] 3-3. Hardening of restoration paint The surface of a soft polyvinyl chloride waterproof sheet with an average thickness of 1.3 mm was washed with water using a brush and then dried. Thereafter, at room temperature (23°C), 400 g / m of the repair paint of each Example and Comparative Example was applied to the surface of the waterproof sheet using a roller brush. 2 A coating film was formed by coating in an amount of 1000g / g.

[0088] The coating was then dried for 12 hours at room temperature (23°C), after which the state of the repair layer obtained by drying and hardening was visually observed, and the results were evaluated using the following criteria.

[0089] <Judgment criteria> ◎: The coating is almost completely dry (hardened). A dry repair layer is formed on the tarpaulin ○: There are some areas of the coating that are not yet dried, It can be said that a dry repair layer has formed on the waterproof sheet. ×: The coating film is clearly not dry (hardened), It was not possible to form a repair layer on the waterproof sheet.

[0090] 3-4. Weather resistance of repair layer The surface of a soft polyvinyl chloride waterproof sheet with an average thickness of 1.3 mm was washed with water using a brush and then dried. Thereafter, at room temperature (23°C), 400 g / m of the repair paint of each Example and Comparative Example was applied to the surface of the waterproof sheet using a roller brush. 2 After forming a coating film by applying the coating amount of 100g / m2, the coating film was dried to form a repair layer on the surface of the waterproof sheet.

[0091] The repair layers formed using the repair paints of each of the Examples and Comparative Examples were then subjected to a metal halide lamp test (black panel temperature: 80°C, irradiance: 81 W / cm 2 After 600 hours of exposure to water (water spray: 2 minutes out of 120 minutes), the repair layer was visually observed to see if it had peeled off from the waterproof sheet, and the results were evaluated using the following criteria.

[0092] <Judgment criteria> ◎: No peeling of the repair layer from the waterproof sheet is observed ○: Some peeling of the repair layer from the waterproof sheet is observed, but this does not affect use. ×: Clear peeling of the repair layer from the waterproof sheet is observed

[0093] 3-5. Stain resistance of the repair layer The surface of a soft polyvinyl chloride waterproof sheet with an average thickness of 1.3 mm was washed with water using a brush and then dried. Thereafter, at room temperature (23°C), 400 g / m of the repair paint of each Example and Comparative Example was applied to the surface of the waterproof sheet using a roller brush. 2 After forming a coating film by applying the coating amount of 100g / m2, the coating film was dried to form a repair layer on the surface of the waterproof sheet.

[0094] The repair layers formed using the repair paints of each Example and Comparative Example were left in a sunny place for one month in July (summer), and then visually observed for the presence or absence of dirt on the surface of the repair layer and the presence or absence of mold growth.Based on the observation results, they were evaluated using the following criteria.

[0095] <Judgment criteria> ◎: No dirt or mold is found on the surface of the repair layer ○: There is some dirt and mold on the surface of the repair layer, but No problems with use ×: Dirt and mold are clearly observed on the surface of the repair layer.

[0096] 3-6. Resupply of plasticizer from repair layer to waterproof sheet For a waterproof sheet made of soft polyvinyl chloride with an average thickness of 1.3 mm, the content of plasticizer contained in the waterproof sheet was artificially reduced to 60% from the initial content. The surface of this waterproof sheet was washed with water using a brush and then dried. Thereafter, at room temperature (23°C), 400 g / m of the repair paint of each Example and Comparative Example was applied to the surface of this waterproof sheet using a roller brush. 2 After forming a coating film by applying the coating amount of 100g / m2, the coating film was dried to form a repair layer on the surface of the waterproof sheet.

[0097] Then, for the repair layers formed using the repair paints of each Example and Comparative Example, each was left in an oven set to 80°C for 7 days, and the plasticizer content in the waterproof sheet was measured using the Soxhlet extraction method with diethyl ether.The plasticizer recovery rate, calculated based on the measured value, i.e., the plasticizer content in the waterproof sheet after being left alone compared to the initial waterproof sheet, was evaluated using the following criteria.

[0098] <Judgment criteria> ◎: The plasticizer content in the waterproof sheet after standing is 65% or more. ○: The plasticizer content in the waterproof sheet after standing is 62% or more and less than 65%. ×: The plasticizer content in the waterproof sheet after standing is less than 62%.

[0099] The content of the plasticizer in the waterproof sheet was measured by the ether extraction method.

[0100] 3-7. Summary The evaluation results obtained for 3-1. Surface properties of the repair layer, 3-2. Flowability of the repair paint on a slope, 3-3. Hardening of the repair paint, 3-4. Weather resistance of the repair layer, 3-5. Stain resistance of the repair layer, and 3-6. Resupply of plasticizer from the repair layer to the waterproof sheet are shown in Table 1.

[0101] [Table 1]

[0102] As shown in Table 1, the repair paint in each example contains a resin material, a plasticizer, a filler, water, and a thickener. By forming an emulsion containing a resin material and water in this repair paint, the formation of an uneven pattern on the surface can be accurately suppressed or prevented when a repair layer is formed on the surface of the waterproof sheet, and the results show that a repair layer of approximately uniform thickness can be formed even if the waterproof sheet is placed on an inclined surface.

[0103] In contrast, in the case of the repair paints in each comparative example, if the repair paint did not contain a thickener, when the water content was too high, the viscosity of the repair paint became low, resulting in a repair layer of uniform thickness not being able to be formed when the waterproof sheet was placed on an inclined surface; further, when the water content was too low, the viscosity of the repair paint became high, resulting in an uneven pattern being formed on the surface of the repair layer.

Claims

1. A repair paint used to form a repair layer on the surface of a polyvinyl chloride waterproof sheet that has deteriorated over time by applying it and then drying it. The repair paint contains a resin material, a plasticizer, a filler, water, and a thickener, and an emulsion containing the resin material and the water is formed in the repair paint, The ratio of the content of the plasticizer to the total weight of the repair paint is 15% by weight or more and 30% by weight or less, A repair paint, characterized in that the ratio of the content of the filler to the total weight of the repair paint is 15.7% by weight or more and 22% by weight or less.

2. 2. The repair paint according to claim 1, wherein the resin material is at least one of an ethylene-vinyl acetate copolymer resin, an acrylic resin, and a vinyl chloride resin.

3. 3. The repair paint according to claim 1, wherein the thickener is an associative thickener.

4. The repair paint according to any one of claims 1 to 3, further comprising a surfactant.

5. 5. The repair paint according to claim 1, wherein the thickener is present in an amount of 0.3% by weight or more and 2.0% by weight or less.

6. 6. The repair paint according to claim 1, wherein the water content is 26% by weight or more and 33% by weight or less.

7. 7. The repair paint according to claim 1, wherein the filler comprises hollow silica.

8. 8. The repair paint according to claim 1, wherein the repair paint has a viscosity at 23° C. of 1000 mPa·s or more and 6000 mPa·s or less.

9. 9. The repair paint according to claim 1, wherein the repair paint is applied to the surface of the polyvinyl chloride waterproof sheet by using a roller brush.

10. A repair construction method, comprising applying the repair paint according to any one of claims 1 to 9 to the surface of the polyvinyl chloride waterproof sheet that has deteriorated over time, and then drying the paint to form the repair layer.

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