JP2006088106A - Coating method of concrete floor surface - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a colored coated layer having excellent durability in coating on a floor surface such as a concrete slab. <P>SOLUTION: In a state that a concrete surface is semidry after the lapse of about 1-3 hours after surface finishing after placing the concrete on the floor surface, a concrete floor surface coating is performed with a coating mixed with a transparent lithium-containing solution or colored lithium containing-solution. As a result, parts of the coating coated on the concrete surface is penetrated in the concrete surface, and at the same time, a coated surface of sufficient thickness can be formed on the concrete surface as a coating film, and colored coated layer having excellent durability can be formed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for coating a concrete floor surface, and after forming a floor surface concrete such as a concrete slab, a colored coating film is formed on the floor surface within a predetermined time before the concrete is hardened. The present invention relates to a method for coating a concrete floor surface that forms a colored layer rich in properties.

  For example, in the coating of concrete floors and the like, it is important to perform an appropriate surface treatment so that the coating film is sufficiently adhered to the concrete substrate and can be colored with a strong and predetermined color. If this substrate adjustment is insufficient, there is a problem in that deterioration of coloring unevenness, hue difference, peeling of the coating film, cracking, blistering, choking, etc. occur at an early stage. Therefore, in the past, in the construction work of buildings such as concrete, in the building construction standard specification / comment (JAS18), etc., the usable coating materials and processes are stipulated in detail for each painting object. .

  In the concrete coating floor process, various proposals have been made regarding a base coating material for enhancing the adhesion between the coating film and the concrete substrate, and a coating process (Patent Document 1, Patent Document 2).

  Patent Document 1 discloses a construction method in which, for example, a methyl methacrylate resin is used as a binder in a concrete floor using resin mortar as concrete, and a one-component moisture-curing urethane primer is applied to the surface of the concrete floor.

  In Patent Document 2, after concrete pouring, the concrete is dried until the moisture content of the concrete becomes 5% or less (for example, after 25 days have elapsed from pouring), and then a primer with a predetermined epoxy or urethane primer is used. A processing method is disclosed.

JP-A-6-99137 JP 2000-265654 A

  Since the above-mentioned Patent Document 1 is characterized by using a primer expected for chemical bonding between the resin mortar on the floor side and the base material, the construction method of Patent Document 1 is used as it is for an ordinary mortar concrete base. There is no merit to do.

  Moreover, also in the concrete coating method of patent document 2, the curing period for fully drying concrete is ensured, and after that, an undercoating process and an overcoating process are performed. Therefore, in any case, the concrete substrate and the paint film can be integrated, but the concrete floor construction and the coating substrate adjustment process can be reduced, but at intervals of several hours immediately after the concrete placement. It is not assumed that the painting process will continue.

  By the way, in the case of concrete coating, when the surface treatment process of a concrete base is simplified, the color of the concrete surface and the concrete base may affect the color of the used paint. Also, depending on the type of paint used, the traces of iron and brush coating remain, and so-called unevenness is likely to be formed.

  Therefore, the object of the present invention is to solve the above-mentioned problems of the prior art, and in accordance with the progress of hardening of the concrete surface after placing the concrete, the lithium-containing solution is in a dry state before the occurrence of bleeding water on the concrete surface. By forming a colored coating film with a paint with a base additive, adjustment of the curing of the concrete and the curing of the coating film is achieved, the concrete and the colored coating film are integrated, and the set coloring color is high An object of the present invention is to provide a method for painting a concrete floor surface that is durable.

  As a result of seeking a method for coating a concrete floor surface in which the colored layer of the paint is integrated with the concrete floor and the coating film is durable, the applicant has determined that the lithium-containing solution and It has been found that the above-mentioned problems can be solved by painting with the applied paint. This utilizes the property of absorbing water well when the placed concrete is in a dry state, and the coating film can be stabilized by using a paint containing a lithium-containing solution as a base additive. Characterized by the point found.

  That is, the present invention is a method for painting a concrete floor surface, characterized in that the concrete surface is coated when the concrete surface is dry after about 1 to 3 hours have passed after surface finishing and after surface finishing.

  When finishing the surface after placing the concrete, it is characterized in that it is finished while spraying a paint containing a transparent or coloring material representing the texture, or spraying a fine powder for coloring.

  At this time, it is preferable to use a coating material to which a transparent lithium-containing solution or a colored lithium-containing solution is added.

  A concrete floor surface placed with normal concrete is “freshly dried” on the surface in about 1 to 3 hours after concrete placement and surface finishing. The elapsed time after finishing the concrete surface where this “raw dry” condition appears depends on the site conditions such as concrete mix, ventilation, temperature, etc., but is approximately 1 to 3 hours after placing concrete, up to 5 hours In between, the concrete surface is in this state. In this “raw dry” state, the concrete surface easily absorbs water in a solution state, and in particular, when a paint containing a lithium-containing solution, which is a feature of the present invention, is applied as a base additive, the cured coating film is cured. It was confirmed to be integrated with the concrete surface on

  Therefore, in the present specification, the “raw dry” state means a concrete surface state that appears within an elapsed time of about 5 hours after concrete placement and surface finishing, in particular, a slight drying on the surface in about 1 to 3 hours. Defined as progressing.

  In general, the time required for the paint used for concrete surface coating to dry and harden and to withstand practical use is shorter than the time required for concrete to harden and reach the specified practical strength. Are known. Therefore, even if the concrete is applied in a freshly dried state after placing the concrete, the surface of the coating film is cured to a sufficient practical strength until the concrete is cured. In the coating method using the coloring material using the lithium-containing solution of the present invention as a base additive, a uniform and uniform colored surface can be easily obtained. If the paint is not colorless and transparent such as varnish, the color of the concrete substrate is less affected.

  Also, as a coating method, in addition to forming a colorless and transparent varnish-type coating film, surface finishing is performed while applying a predetermined coloring to the concrete surface by spraying powder coloring material at the time of finishing, and then in a dry state It is also possible to employ a technique of applying a paint that gives gloss.

  According to the present invention, after the concrete is placed, the concrete surface is in a dry state, and a part of the applied paint penetrates the concrete surface, while a coating surface having a sufficient film thickness is formed on the concrete surface as a coating film. be able to. As a result, since this coating film can also act as a curing film that prevents the dissipation of moisture during the hardening period of concrete, according to the present invention, it is possible to achieve high quality by performing concrete coating during raw drying. Durable concrete floor surface can be formed, subsequent curing work can be omitted, the amount of watering required for curing, etc. can be reduced sufficiently, and the use of adjuvants such as curing agents is not required. The work process of surface finishing work can be greatly shortened.

  In addition, since the concrete floor painted during dryness can prevent surface drying, it is possible to prevent cracking due to volume change due to drying of the concrete surface, drying shrinkage, etc., and cracking during curing. Further, it is possible to prevent a change in hue and a decrease in texture due to the curing of the paint.

  Hereinafter, as the best mode for carrying out the method for coating a concrete floor surface of the present invention, the following embodiments will be described with reference to the accompanying drawings.

  After placing concrete on the concrete floor and finishing the surface, the surface will be in a “raw dry” state in about 1 to 3 hours. In the “raw dry” state, a paint using a lithium-containing solution as a base additive is applied. For concrete floors placed with normal concrete, the elapsed time after finishing the concrete surface where the “raw dry” state appears varies depending on the composition, ventilation, temperature, etc., but approximately 1 to 3 hours after placing concrete It is preferable to apply a paint containing a lithium-containing solution as a base additive within about 5 hours at the maximum.

  In this specification, “freshly dried” means concrete surface condition that appears within an elapsed time of about 5 hours after concrete placement and surface finishing, especially with a slight drying on the surface in about 1 to 3 hours. It indicates a certain state.

  In general, the time required for the paint used for concrete surface coating to dry and harden and to withstand practical use is shorter than the time required for concrete to harden and reach the specified practical strength. Are known. Therefore, even if the concrete is applied in a freshly dried state after placing the concrete, the surface of the coating film is cured to a sufficient practical strength until the concrete is cured.

  For coating with a lithium-containing solution as a base additive, adjusting the viscosity and fluidity of the paint used with an appropriate solvent enables various applications such as soldering, sponge coating, brush coating, roller coating, spraying, spray coating, etc. A painting method can be adopted. Needless to say, when a plurality of coating processes such as intermediate coating and finish coating are set, the coating methods can be properly used. Further, at the time of final finishing, it is possible to disperse the surface by spraying a liquid coloring material on the concrete surface. In this case, it is preferable to use an air-drying paint containing a colored lithium-containing solution.

  As the base additive to be added to the paint used in the present invention, a transparent lithium-containing solution or a colored lithium-containing solution exhibiting a texture is effective. The type of coating material is not limited as long as it is a coating material having a fluidity and viscosity that can be applied during raw drying using a lithium-containing solution as a base additive. For example, it is also possible to use a paint mixed with a lithium-containing solution, such as the trade name “Pentola Seal” of Suruga Kogyo Co., Ltd. It is also possible to add a “pentora seal” just before application. If a lithium-containing solution is used as a base additive, different types of paint can be applied repeatedly. Emulsion paints and water-soluble paints are ready-made paints and can be easily applied to concrete surfaces in a dry state when a lithium-containing solution is used as a base additive.

As the coloring material used in the present invention, a transparent or colored lithium-containing solution is effective. For example, the trade name “AST COLOR” of AST UNION Co., Ltd., which is mainly composed of a mixture of lithium and styrene maleic acid is suitable. This colorant is used for spraying on the concrete surface immediately after placing and coloring the concrete surface during surface finishing. Its application rate, the mixing of concrete, the concrete foundation colors, varies depending on subsequent method painting, coating unit amount per example 3~12m ² / liter, preferably sprayed on the floor area of about 5~9m ² / l ( Application) makes it possible to form a required coating film.

[Concrete crack prevention coating]
In the present invention, when the concrete surface is in a dry state, a lithium-containing solution is used as a base additive, and a coating film is formed and applied to the surface.
(1) Suppression of cracks due to drying shrinkage
(2) Prevention of cracks that may occur due to insufficient curing
(3) Suppression of cracks caused by volume changes due to drying
(4) An effect of suppressing plastic shrinkage cracking can be obtained.

  In other words, drying shrinkage occurs from the surface of the member under the influence of the strain gradient introduced in the cross section of the member when the moisture in the concrete escapes from the surface of the member. When deformation occurs and is constrained, tensile stress is generated leading to cracks that penetrate the entire cross section. As in the present invention, it is preferable to promote the effect as a sealing curing by forming a coating film on the concrete surface during dry drying.

  Also, insufficient curing increases the degree of cracking that occurs in the hardened concrete. Early truncation of the curing increases the shrinkage of the concrete at the young age. Insufficient cement hydration due to drying not only reduces long-term strength, but also impairs durability. Therefore, it is preferable to form a coating film on the concrete surface when the concrete surface is dry.

  When the internal stress due to concrete creep, temperature difference and drying shrinkage acts on the concrete volume change due to concrete hardening, cracks are easily generated in concrete slabs whose ends are supported and constrained. Therefore, by forming a coating film on the concrete surface when these concrete surfaces are dry, an effect as a sealing curing can be obtained, and cracks caused by volume changes due to drying from the concrete surface can be prevented.

  Plastic shrinkage cracks occur when moisture buildup from cast concrete that has not yet solidified is faster than the bleeding speed to the concrete surface. It is known that this plastic shrinkage crack starts to occur immediately after the concrete is cast. Therefore, by forming a coating film on the concrete surface when the concrete surface is dry, the evaporation rate from the concrete surface can be reduced and plastic shrinkage cracks can be suppressed.

  In addition, when the concrete surface is dry, forming a coating film on the concrete surface also has an effect of advancing the final finishing time. Therefore, when the concrete reaches a predetermined practical strength, the coating surface also reaches a sufficient strength.

  As a sealer using a lithium-containing solution as a base additive used for coloring a concrete surface in a concrete floor surface or a general concrete hardening process according to the present invention, for example, lithium silicate of Suruga Kogyo Co., Ltd. is mainly used. It is preferable to use a concrete surface hardener as a component, a trade name “Pentra Seal” or “Pentra Seal 244”. Thereby, more excellent durability, weather resistance, surface hardness, and abrasion resistance can be improved on the concrete surface.

Hereinafter, the example which confirmed the effect by this invention by the some construction example applied to the concrete floor surface of various structures is shown.
[Construction Example 1]

  Reinforced concrete two-story building half-precast concrete slab floor (slab thickness 22cm, precast concrete slab thickness 8cm), unit cement amount 360kg, fine aggregate rate 55%, water cement ratio 45%, slump 16cm concrete The site was placed in two days. The second floor is covered with a slate roof, and concrete is supplied by pumping up to the second floor height. The color of the concrete substrate handed over twice was quite different. After placing the concrete divided into two days, the concrete surface was ready to dry in about 90 minutes after placing.

  The surface of each dry concrete placed in two days was brushed twice using the trade name “AST COLOR GRAY” of AST UNION Co., Ltd. A part of the floor area was left uncoated for comparison. The painting work was easy and no unevenness was found on the painted surface. Even in areas where the color was different on the concrete substrate, no difference in hue was observed after painting.

  The structure of Construction Example 1 started to be used as a warehouse 3 weeks after the concrete was placed on the concrete floor, but the painted and unpainted floors had no problem in actual use. The paint was painted in a vivid designated color with the color of the concrete base suppressed, and there were fewer cracks compared to the unpainted part. The cracks that occurred on the unpainted floor were presumed to be due to drying shrinkage, but the progress (width, length, range) of cracks was observed even after 3 months of concrete placement.

[Example 2]
Using concrete with a unit cement amount of 300 kg, a fine aggregate ratio of 60%, a water cement ratio of 50%, and a slump of 16 cm, a concrete running surface of an outdoor parking lot was continuously placed. Since the placement area was large, we received ready-mixed concrete (fresh concrete) from two ready-mixed concrete factories, and finished the surface with the bunnian striker tube method. Both types of ready-mixed concrete differed in aggregate and cement, and the color of the finished concrete substrate surface was quite different. The concrete slab thickness was 12 cm, and the concrete started to dry out after about 60 minutes.

  The freshly dried concrete surface was brushed twice using the trade name “Ast Color Blue” of Ast Union Co., Ltd. There was no unevenness on the painted surface, and there was no difference in hue on the painted surface, despite the difference in color of the concrete substrate, indicating a homogeneous hue and texture.

[Construction Example 3]
An outdoor parking lot was laid with concrete having the same ready-mixed concrete condition (slump 12 cm) as in Construction Example 2. The ready-mixed concrete was directly unloaded from the ready-mixed car and finished with the Bunia striker tube method. The concrete thickness was 12 cm, and the concrete started to dry after about 60 minutes.

  Using a product name “AST COLOR” of AST UNION CO., LTD. In addition, the product name “AST COLOR TOP COAT (with fluorine)” of AST UNION Co., Ltd. was brushed onto the dry painted surface. Although it was a coloring operation close to a continuous process, the painting operation was easy, and no unevenness was observed on the painted surface.

[Construction Example 4]
Using concrete of the same composition as construction example 1, the second floor (deck plate laying, slab thickness 25 cm) of a reinforced concrete two-story building with a similar structure was placed on site for two days. The second floor was covered with a steel ALC panel roof, and concrete was supplied by pumping to the second floor height. The color of the concrete substrate handed over twice was quite different. After placing the concrete divided into two days, after finishing the trowell, the concrete surfaces were both dried and started to dry in about 60 minutes.

  The product name “AST COLOR YELLOW” of AST UNION Co., Ltd. was sprayed twice vertically and horizontally on each freshly dried concrete surface placed in two days. A part of the floor was not painted for comparison. No unevenness was observed on the painted surface. Regardless of the difference in the color of the concrete substrate placed on both days, no difference in hue on the painted surface was observed. Further, a concrete surface hardener mainly composed of lithium silicate from Suruga Kogyo Co., Ltd., trade name “Pentola Seal” was applied to the entire floor surface with a brush after 3 weeks had passed since the concrete was placed.

  The structure of Construction Example 4 began to be used as a warehouse after 6 weeks of placing the second floor concrete. There was no problem in actual use in both painted and unpainted areas, but the colored painted floor had much fewer cracks than unpainted areas. The entire floor was glossy in both painted and unpainted areas, with a so-called mirror finish. The painted part showed a more vivid color. In addition, although the crack which generate | occur | produced in the unpainted floor was based on drying shrinkage | contraction, after 3 months of concrete pouring, a change was not especially recognized, and the water absorption by water washing was not recognized.

Claims (4)

  After placing concrete, after about 1 to 3 hours after surface finishing, when the concrete surface is dry, it is coated with a paint containing a transparent lithium-containing solution or a colored lithium-containing solution. How to paint.   A method for painting a concrete floor, characterized in that, when finishing the surface after placing the concrete, the paint is finished while spraying a paint containing a transparent or colored material representing the texture.   A method for painting a concrete floor, characterized in that, when finishing the surface after placing the concrete, it is finished by spraying fine powder for coloring.   4. The concrete surface according to claim 2 or 3, wherein the concrete surface is painted with a paint added with a transparent lithium-containing solution or a colored lithium-containing solution when the concrete surface is dry after one to three hours have passed since the concrete surface finish. How to paint concrete floor.