JP2013155062A - Surface-coating material of concrete structure and abnormality-detecting method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface-coating material of a concrete structure enabling to obtain abnormality detection over a long period of time without deteriorating the quality of concrete.SOLUTION: This surface-coating material comprises a combination of a polymer surface-coating material as a coating material and defect-control type strontium aluminate as a stress illuminant material. Fine particles of the defect-control type strontium aluminate are added by 0.3-20 wt.% to the polymer surface-coating material.

Description

  The present invention detects abnormal deformations and cracks generated in a concrete structure simply by applying it to the concrete structure, and displays it quickly by light so that it can be visually confirmed. The present invention relates to a surface covering material that can prevent damage to the surface and a method for detecting deformation of a concrete structure using the surface covering material.

  In order to detect abnormal deformations and cracks that occur in concrete structures and prevent damage by preventing the destruction of concrete structures, the stress generated in the concrete structure is applied to the concrete structure. Surface coating materials that can emit light and can notify the occurrence of abnormal deformation and cracks have already been proposed.

  As a conventional surface coating material, it has a structure in which a stress luminescent material is added to an aqueous coating composition or ink composition to be a coating material, and the aqueous coating composition includes an acrylic resin, an acrylic silicon resin, A urethane-based resin and a vinyl acetate-based resin are used, and a colorless and transparent medium is used as the ink composition.

  Here, as a stress-stimulated luminescent material having excellent light emission luminance, defect control type strontium aluminate and the like are already known, and surface coating is performed by mixing an appropriate amount thereof with the above-described aqueous coating composition or ink composition. (For example, refer to Patent Document 1 or 2).

  When such a surface coating material is applied to the surface of a concrete structure, if abnormal deformation or cracks occur in the concrete structure, mechanical strain energy is added to the stress-stimulated luminescent material to cause a light emission phenomenon. Thus, the abnormal deformation generated in the concrete structure can be visually confirmed, and the collapse of the concrete structure can be prevented.

JP 2011-94041 A JP 2001-49251 A

  By the way, since the above-mentioned conventional surface coating material uses a water-based paint composition or an ink composition as a coating material, the coating film has water shielding properties and is contained in concrete in a state where it is applied to a concrete structure. There is a problem that the quality of the concrete is deteriorated.

  In addition, since the water-based paint composition or ink composition is weak in light resistance and easily hardens, for example, the followability to cracks generated in a concrete structure is not short-term, and long-term deformation detection is performed on the concrete structure. Is something you can't get.

  Therefore, an object of the present invention is to provide a surface covering material for a concrete structure and a deformation detection method using the same, which can obtain long-term deformation detection without deteriorating the quality of the concrete.

  In order to solve the above problems, the invention of claim 1 is obtained by adding a stress luminescent material to a polymer surface covering material as a coating material.

  The invention according to claim 2 uses defect-control strontium aluminate as the stress-stimulated luminescent material, and 0.3 to 20% by weight of the defect-control strontium aluminate fine particles are added to the polymer surface coating material. Is.

  In the invention of claim 3, when the surface covering material according to claim 1 or 2 is applied to the surface of a concrete structure and the concrete structure is deformed or cracked, the crack emits stress through the coating film. The stress-stimulated luminescent material is caused to emit light by the stress applied to the body material so that a crack generated in the concrete structure can be visually confirmed.

  Here, the coating film made of the polymer surface coating material is not only excellent in the function of blocking various deterioration factors such as rainwater, ultraviolet rays, heat, and carbon dioxide gas, but also has the property that only water vapor can be selectively passed. Therefore, the moisture content inside the concrete can be reduced when applied to the concrete structure, and the quality of the concrete is not deteriorated.

  Moreover, since the coating film made of the polymer surface coating material is excellent in light resistance, it can maintain flexibility for a long period of time and has a long-term followability to cracks in the concrete structure.

  According to the present invention, since the polymer surface coating material is used as the coating material of the surface coating material mixed with the stress luminescent material, the concrete structure may be deformed or cracked when applied to the surface of the concrete structure. Occurs, light is emitted by applying stress to the stress-stimulated luminescent material, and the occurrence of deformation and cracks can be visually confirmed by light emission, so that the collapse of the concrete structure can be prevented in advance, and the polymer The surface coating material is not only excellent in the function of blocking various deterioration factors such as rainwater, ultraviolet rays, heat, carbon dioxide gas, etc. The moisture content inside the concrete can be reduced while it is applied to the object, enabling rapid application to the concrete structure immediately after completion, thereby reducing the quality of the concrete. Succoth is not.

  In addition, the coating film made of a polymer surface coating material has excellent light resistance, so it can maintain flexibility over a long period of time, has a long-term followability to cracks in concrete structures, etc. By eliminating the need for repainting, costs can be reduced.

  Embodiments of the present invention will be described below.

  The surface covering material for a concrete structure according to the present invention is formed by adding a stress luminescent material to a polymer surface covering material that is a coating material.

  The polymer surface covering material has flexibility, can follow the deformation and cracks generated in concrete well, and at the same time is excellent in waterproofness and moisture permeability. Examples of the polymer surface covering material include an acrylic rubber composition and a crosslinked product thereof, an acrylic urethane resin and a crosslinked product thereof, an acrylic silicone resin and a crosslinked product thereof, a polyurethane resin composition and a crosslinked product thereof, and the like. These components may be contained alone or in combinations of two or more.

  The acrylic rubber-based composition is preferably made of an acrylic rubber-based copolymer having an alkyl (meth) acrylate having an alkyl group having 4 to 10 carbon atoms and a copolymerization ratio of 30 to 98% by weight. Specific examples of the alkyl (meth) acrylate having 4 to 10 carbon atoms in the alkyl group include n-butyl (meth) acrylate, iso-butyl (meth) acrylate, sec-butyl (meth) acrylate, n-amyl ( (Meth) acrylate, iso-amyl (meth) acrylate, n-hexyl (meth) acrylate, n-hexyl (meth) acrylate, n-pentyl (meth) acrylate, oxoheptyl (meth) acrylate, n-octyl (meth) acrylate , 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate, oxononyl (meth) acrylate, n-decyl (meth) acrylate, oxodecyl (meth) acrylate, and the like. Alkyl (meth) acrylates having an alkyl group with less than 4 carbon atoms are not preferred in terms of alkali resistance, while those with more than 10 carbon atoms are less resistant to cold. The copolymerization ratio of the monomer needs to be 30 to 98% by weight, and preferably 50 to 90% by weight. When this ratio is less than 30% by weight, the coating film has cracks in the underlying crack, water resistance and alkali resistance. On the other hand, if it exceeds 98% by weight, a coating film having sufficient strength may not be obtained.

  In addition to the alkyl (meth) acrylate having 4 to 10 carbon atoms in the alkyl group, the acrylic rubber copolymer is copolymerized with other monomers having an unsaturated ethylene bond copolymerizable therewith. Is done. As this "other monomer", (meth) acrylic acid, styrene, acrylonitrile, vinyl acetate, vinyl chloride, butadiene, (meth) acrylic acid, glycidyl (meth) acrylate, N-methylol (meth) acrylamide and carbon Examples thereof include alkyl (meth) acrylates of 1 to 3.

  The acrylic rubber-based composition is excellent in safety and excellent in workability because it is a one-pack type, and the obtained coating film is not sticky, and has water resistance, chemical resistance, ultraviolet resistance and ozone resistance. It is preferable that it consists of the aqueous emulsion of an acrylic rubber-type copolymer at the point which is favorable. In addition, it is preferable that the ratio of the acrylic rubber-type copolymer in an emulsion is 30 to 70 weight%.

  This acrylic rubber copolymer emulsion is obtained, for example, by emulsion polymerization of the monomer in the presence of a surfactant. As the surfactant, any of anionic, nonionic and cationic can be used. It is preferable that the compounding quantity of surfactant is 0.1 to 10 weight% with respect to 100 weight part of acrylic rubber-type copolymers. When the amount of the surfactant is less than 0.1% by weight, the emulsion lacks stability. On the other hand, when the blending amount exceeds 10% by weight, the drying property and the water resistance of the coating film are lowered.

  In addition, the crosslinked product of the acrylic rubber-based composition was obtained by polymerizing the above-described alkyl (meth) acrylate having an alkyl group having 4 to 10 carbon atoms and (meth) acrylate having a glycidyl group. A reaction product obtained by reacting a copolymer with a compound having a hydroxyl group or an amino group; the alkyl (meth) acrylate having an alkyl group having 4 to 10 carbon atoms and a hydroxyl group as described above; And a reaction product obtained by reacting a copolymer obtained by polymerizing (meth) acrylate and the like with a compound having a glycidyl group. Examples of the compound having a hydroxyl group, glycidyl group or amino group include glyoxal, ethylene glycol, (poly) ethylene glycol diglycidyl ether, (poly) propylene glycol diglycidyl ether, (di) glycerol polyglycidyl ether, and polyglycerol poly. A glycidyl ether, epichlorohydrin, ethylenediamine, etc. are mentioned.

  As the acrylic urethane resin, the ester portion has a hydrocarbon group having 1 to 18 carbon atoms, preferably 4 to 10 carbon atoms, and one hydrogen atom contained in this hydrocarbon group is substituted with a hydroxyl group. Examples thereof include resins obtained by reacting a hydroxyl group-containing (meth) acrylic acid ester compound with an isocyanate group-terminated urethane prepolymer.

  Examples of the crosslinked product of the acrylic urethane resin include a reaction product obtained by reacting the above acrylic urethane resin and polyisocyanate; a resin obtained by reacting acrylic polyol and polyisocyanate;

  The acrylic polyol can be obtained by radical polymerization of an acrylic monomer having a hydroxyl group alone, or this acrylic monomer and another polymerizable monomer having an unsaturated carbon-carbon bond. Acrylic polyol can be used, and other polyester-modified acrylic polyols can be used.

  The polyisocyanate is not particularly limited as long as it has two or more isocyanate groups. 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 2 , 4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, and the like; hexamethylene diisocyanate (HMDI), tetramethylene diisocyanate, 2-methyl-pentane-1 , 5-diisocyanate, 3-methyl-pentane-1,5-diisocyanate, lysine diisocyanate, trioxyethylene diisocyanate and other aliphatic diisocyanates; xylylene-1,4-diisocyanate, Aroaliphatic diisocyanates such as silylene-1,3-diisocyanate (XDI) and tetramethylxylylene diisocyanate; isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated tetramethylxylylene diisocyanate And alicyclic diisocyanates such as Isocyanurates and piurets of these compounds can also be used.

  Acrylic silicone resins include (co) polymers obtained by radical polymerization of (meth) acrylic monomers having an alkoxysilyl group in the side chain; (meth) acrylic monomers having an alkoxysilyl group in the side chain. A copolymer obtained by radical polymerization of a monomer and another polymerizable monomer having an unsaturated carbon-carbon bond; unsaturated carbon-carbon in the presence of one of these (co) polymers (Meth) acrylic silicone graft resin obtained by radical polymerization of a polymerizable monomer having a bond; (Me) a (co) polymer containing a structural unit derived from an acrylic monomer and polyorganosiloxane And a block polymer or graft polymer obtained by reacting with.

  The other polymerizable monomer having an unsaturated carbon-carbon bond is not particularly limited as long as it is an unsaturated compound having radical polymerizability. For example, aromatic vinyl compounds, vinyl compounds having amino groups, vinyl compounds having amide groups, vinyl compounds having alkoxyl groups, conjugated diene compounds, maleimide compounds, vinyl ester compounds, vinyl ether compounds, vinyl compounds having glycidyl groups, Examples thereof include monoalkyl esters of unsaturated dicarboxylic acids and dialkyl esters of unsaturated dicarboxylic acids. These can be used alone or in combination of two or more.

  Examples of the crosslinked product of the acrylic silicone resin include reaction products obtained by reacting the acrylic silicone resin with polyisocyanate.

  The polyurethane resin is not particularly limited as long as it has two or more urethane bonds in the molecular chain. A polyol having an unsaturated carbon-carbon bond, a polyisocyanate, and a chain used as necessary. Examples thereof include a polyurethane resin obtained by reacting with a long extender.

  The polyol having an unsaturated carbon-carbon bond has at least one polymerizable unsaturated carbon-carbon bond and two or more hydroxyl groups. Specific examples thereof include hydroxyl group-containing polybutadiene, hydroxyl group-containing Examples thereof include hydroxyl group-containing diene polymers such as polypentadiene, hydroxyl group-containing polyhexadiene, and hydroxyl group-containing polybutadiene / polyisoprene. The position of the hydroxyl group in the hydroxyl group-containing diene dish break is not particularly limited. Accordingly, a diene polymer having hydroxyl groups at both ends of the molecular chain main chain, a diene polymer having hydroxyl groups at both the molecular chain side chain terminal and the molecular chain main chain terminal can be used.

  As the polyisocyanate, the compounds exemplified above can be used.

Examples of the chain extender include low molecular weight polyols and low molecular weight polyamines.
Examples of the low molecular weight polyol include ethylene glycol, diethylene glycol, triethylene glycol, propanediol (1,2-propanediol, 1,3-propandiol, 2-methyl-1,3-propanediol, etc.), dipropylene glycol, Butanediol (1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 2,3-dimethyl-2,3-butanediol, etc.), neopentyl glycol, Diols such as pentanediol, hexanediol, heptanediol, octanediol, 1,6-cyclohexanedimethylol, aniline diol, bisphenol A diol; triols such as glycerin, trimethylolpropane, hexanetriol; pentaerythris Tall, tetraol or hexanol, etc. sorbitol. Examples of the low molecular weight polyamine include aliphatic polyamines such as ethylenediamine, propylenediamine, petitylenediamine and hexamethylenediamine; alicyclic polyamines such as isophoronediamine and piperazine; aromatic polyamines and the like.

  As a crosslinked product of a polyurethane resin, the above-described polyurethane resin may have a crosslinked structure formed using an unsaturated carbon-carbon bond portion derived from a polyol. Such a crosslinked structure can be formed by using, for example, a radical polymerization initiator, an organic sulfur compound, or the like. Specific examples of the crosslinked structure include reacting polyurethane shelves in the presence of radical polymerization initiators such as organic peroxides and azo compounds to directly bond unsaturated carbon-carbon bonds derived from polyols. Cross-linking structure; in the presence of a cross-linking agent such as an organic peroxide or an organic sulfur compound, the polyurethane shelf essences are reacted with each other so that unsaturated carbon-carbon bonds derived from the polyol are cross-linked with a cross-linking agent such as an organic sulfur compound. And a crosslinked structure crosslinked through a structure part derived from the above.

  Moreover, as a crosslinked polyurethane, what was obtained using the isocyanate group terminal urethane prepolymer and the hardening | curing agent may be used.

  As the isocyanate group-terminated urethane prepolymer, one obtained by reacting a polyol and a polyisocyanate can be used.

  As the polyol, one or more of low molecular polyols such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, cyclohexanedimethanol, glycerin, 1,1,1-trimethylolpropane, and the like , Glutamic acid, adipic acid, pimelic acid, suberic acid, sebacic acid, terephthalic acid, isophthalic acid, dimer acid and other low molecular weight carboxylic acids and oligomers with one or more condensation polymers, propion Polyester ether polyols such as ring-opening polymers such as lactone, valerolactone, caprolactone, etc .; polyethylene glycol, polypropylene glycol, polypropylene triol, polyglycerin, polytrimethylolpropane, polyhexanetriol, polybutanediol, poly Hydroxyphenyl methane, poly dihydroxyphenyl propane, polyether polyols such as polyoxytetramethylene oxide; polymer polyols; polycarbonate polyols; polybutadiene polyols, hydrogenated polybutadiene polyols; and the like.

  As the polyisocyanate, the compounds exemplified above can be used.

  Examples of the curing agent used for forming the crosslinked polyurethane include polyamines having two or more amino groups, polyols having two or more hydroxyl groups, polymercaptans, and phenol resins.

  Among the polyamines, amine compounds having two amino groups include ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6- Hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,12-dodecanediamine, 1,14-tetradecanediamine, 1,16-to Xadecanediamine, hexamethylenediamine, trimethylhexamethylenediamine, iminobispropylamine, methyliminobispropylamine, 1,5-diamino-2-methylpentane, isophoronediamine, 1,3-bisaminomethylcyclohexane 1-cyclohexylamino-3-aminopropane, 3 Aliphatic diamines such as aminomethyl-3,3,5-trimethyl-cyclohexylamine, dimethyleneamine having a norbornane skeleton, and metaxylylenediamine (MXDA); 3,3′-dichloro-4,4′-diaminodiphenylmethane ( MOCA), 4,4′-diaminodiphenylmethane, 2,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 2,2′-diaminopiphenyl, 3,3 '-Diaminobiphenyl, 2,4-diaminophenol, 2,5-diaminophenol, 0-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,3-tolylenediamine, 2,4-tolylenediamine, 2,5-tolylenediamine, 2,6-tolylenediamine, 3,4-toluene Aromatic diamines such as phenylenediamine and the like.

  Among the polyamines, examples of the amine compound having three or more amino groups include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine.

As the polyamine, a ketimine in which the amino group in the exemplified compounds is blocked with a ketone or an aldimine blocked with an aldehyde can be used.
The above exemplified compounds can be used as the polyol.
Examples of the polymercaptans include polymercaptocarboxylic acid amides.

  The polymer surface coating material is blended with a filler for the purpose of toughening the coating layer obtained from the coating material, reducing the adhesiveness of the coating layer surface, and improving the workability. Also good. The blending amount of the filler is preferably 30 to 300 parts by weight, and more preferably 50 to 150 parts by weight with respect to 100 parts by weight of the acrylic rubber copolymer.

  When the blending amount of the filler exceeds 300 parts by weight, the adhesion, elongation and waterproof function of the coating layer may be impaired. Specific examples of the filler include cinnabar, talc, calcium carbonate, kaolin, gypsum, diatomaceous earth, titanium oxide, and one or more cements such as various Portland cement, blast furnace cement, and alumina cement.

  In addition, when mix | blending cements as a filler, it is preferable that the compounding quantity shall be 10-200 weight part with respect to 100 weight part of acrylic rubber-type copolymers. When the blending amount is less than 10 parts by weight, the strength of the coating layer is undesirably lowered. On the other hand, if the blending amount exceeds 200 parts by weight, the flexibility of the coating layer is lowered, the followability to cracks is insufficient, and the waterproof property may be impaired. Moreover, a viscosity stabilizer, an antifoamer, etc. can be mix | blended with the said acrylic rubber-type composition in the range of 5 weight part or less with respect to 100 weight part of acrylic rubber-type copolymers as needed.

  The coating layer formed from the polymer surface coating material preferably has a tensile elongation at break of 100% to 2,000%, more preferably 200% to 1,000%, and more preferably 200% to More preferably, it is 500%. When the tensile elongation at break of the film is within the above range, the following property to the crack of the concrete is good, and sufficient waterproofness is obtained. The tensile elongation at break is a measured value according to JIS A 6021 using a film having the preferred thickness.

The water vapor permeability of the coating layer formed from the polymer surface coating material is preferably 5 g / m ² · day or more. If the water vapor permeability is 5 g / m ² · day or more, moisture inside the concrete can be released and the concrete can be dried. For this reason, there is no possibility of inducing an alkali aggregate reaction, swelling of the coating layer due to moisture from the inside of the concrete, or deterioration of the resin forming the fiber reinforced resin layer.

  The thickness of the coating layer is preferably 0.2 to 5 mm, and more preferably 0.5 to 2 mm. If the thickness is less than 0.2 mm, the followability with respect to the cracks of the concrete may be insufficient, and waterproofness may not be obtained.

  On the other hand, if the thickness exceeds 5 mm, the water vapor permeability becomes small, so that the inside of the concrete cannot be dried, and there is a possibility that an alkali aggregate reaction is induced or the coating layer is swollen.

  In order to form a coating film layer from this polymer surface coating material, for example, an ordinary method such as coating with a trowel, brush or roller, or spraying with a machine such as a ricin gun or a spray gun may be used. The viscosity at the time of coating varies depending on the construction method, but it is preferably 300 cps or more (B-type viscometer, 12 rotations, rotor No. 4, 20 ° C.) because of excellent workability, more preferably 1000 to 50000 cps. It is. If the viscosity is less than 300 cps, it is difficult to apply a thick coat at once. When the viscosity exceeds 50000 cps, there is an advantage that thick coating can be performed, but there is a case where a difficulty occurs in construction.

  Next, as the stress luminescent material to be added to the polymer surface coating material, a known stress luminescent material can be used, but since luminescence can be confirmed with the naked eye, it contains europium or cerium as the central ion of the luminescent center. Defect controlled strontium aluminate is preferred. These stress luminescent materials are added to the polymer surface coating material in the form of fine particles. The addition amount is preferably 0.3 to 20% by weight, more preferably 0.5 to 15% by weight, and further preferably 1 to 10% by weight with respect to the polymer surface coating material. preferable.

  The defect-controlled strontium aluminate has a function of emitting green light at a luminance proportional to the stress when mechanical stress is applied. The average particle diameter of the defect-controlled strontium aluminate is preferably 1 to 100 μm, more preferably 5 to 80 μm, and still more preferably 10 to 70 μm. In addition, the average particle diameter in this specification is a value measured by an electrical detection band type particle size distribution measuring device or a laser diffraction type particle size distribution measuring device.

  In addition, when the addition amount of the defect control type strontium aluminate added to the polymer surface coating material is less than 0.3% by weight, the light emission amount in the coating film is small and the visual confirmation becomes difficult. On the other hand, when the amount added exceeds 20% by weight, the tensile elongation at break of the coating layer tends to decrease.

  The polymer surface covering material of the present invention has the above-described configuration, and the surface covering material is provided on a surface of various concrete structures such as bridge piers, sloped slope retaining walls, and buildings with a predetermined thickness. Apply and dry.

  In the surface covering material that covers the surface of concrete structures, the acrylic rubber-based composition that is the base material has not only an excellent function of blocking various deterioration factors, but also has the property that only water vapor can be selectively passed. Therefore, the moisture content inside the concrete can be reduced even after construction, and can be applied to a concrete structure immediately after completion.

  The acrylic rubber-based composition is a water-based material, has almost no organic solvent odor, strange odor, skin irritation, etc., is friendly to the surrounding environment and workers, and has excellent flexibility. Therefore, a seamless coating film can be formed even for a complicated shape, and has a followability to a crack of a concrete structure by maintaining flexibility over a long period of time.

  When a crack occurs in a concrete structure coated with the above surface covering material on the surface, the coating extends along the portion corresponding to the crack, and the coating extends to add to the acrylic rubber-based composition. Some defect-controlled strontium aluminate is subjected to mechanical stress. Therefore, the stress-controlled defect-controlled strontium aluminate emits light, and this light emission causes visual observation of the occurrence of cracks in the concrete structure and the cracked portion. By quickly repairing the cause of cracking, the concrete structure can be prevented from collapsing.

  A mixture of 10 parts of hydroxyethyl methacrylate and 20 parts of hydroxyethyl acrylate as the hydroxyl group-containing (meth) acrylate, 70 parts of 2-ethylhexyl acrylate as the ethylenically unsaturated monomer, and 2,2′-azobisiso as the initiator Polymerization reaction was performed using butyronitrile to obtain a copolymer A. As for the molecular weight of copolymer A, Mn was 8,800, Mw was 19,000, and polydispersity was 2.2. The hydroxyl group concentration was 2.60 meq / g.

100 parts of copolymerization holiday A, 2 parts of propylene glycol, 10 parts of fine powder silica gel (surface area 450 m ² / g, pore volume 0.8 cc / g, refractive index 1.47) with an average particle diameter of 8 μm, polysiloxane antifoaming agent BYK-066 [manufactured by Tetsutani Co., Ltd.] was added to a planetary mixer, stirred at room temperature for 15 minutes, and then kneaded at 70 ° C., followed by dehydration in vacuum for 1 hour to obtain a mixture B It was.

  Next, 100 parts (2.34 meq / g) of the mixture B, and defect-controlled strontium aluminate containing europium with the average particle size and addition amount changed as shown in Table 1 below as the luminescence center were added, and further hexane was added. A methylene diisocyanate isocyanurate (Sumijour N3300, NCO group content 21.8 meq / g, manufactured by Sumitomo Bayer Urethane Co., Ltd.) was added at an NCO / OH equivalent ratio of 1.0, and the mixture was sufficiently stirred to produce a composition. did.

The obtained composition was immediately poured onto a Teflon (registered trademark) plate to a thickness of about 0.5 mm, and allowed to stand at 20 ° C. and a humidity of 60% for 12 hours to be cured. Visibility of light emission was observed by applying a stress to the transparent cured film combined with the obtained defect control type strontium aluminate with a tensile tester. The results are shown in Table 1.

Claims (3)

  A surface covering material for a concrete structure in which a stress luminescent material is added to a polymer surface covering material that is a coating material.   The concrete according to claim 1, wherein defect-stressed strontium aluminate is used as the stress-stimulated luminescent material, and 0.3 to 20 wt% of the defect-controlled strontium aluminate fine particles are added to the polymer surface coating material. Surface covering material for structures.   When the surface covering material according to claim 1 or 2 is applied to the surface of a concrete structure and a crack occurs in the concrete structure, the stress light emitter is applied by stress applied to the stress light emitter material through the coating film due to the crack. A method for detecting a change in a concrete structure by causing the material to emit light and visually confirming a crack generated in the concrete structure.