JP2010270258A - One-part moisture-curable urethane-based adhesive composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an one-part moisture-curable urethane-based adhesive composition adjustable to a proper viscosity, using a diluent as no VOC in the "small chamber method test" specified by JIS A 1901:2003, which is not only good in combed-line unevenness and nonstickiness but also capable of imparting adhesiveness and floor squeak-proofness. <P>SOLUTION: The moisture-curable urethane-based adhesive composition includes: (A) a urethane prepolymer obtained by reaction between a polyisocyanate compound and a polyol having two or more active hydrogen atoms on the molecular end; (B) a filler; (C) an additive; and (D) a component, as a diluent, as a no volatile organic compound (VOC) in the "small chamber method test" specified by JIS A 1901: 2003. The adhesive composition preferably contains polyethylene fibers as the additive (C) which further contains silica. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a one-part moisture curable urethane-based adhesive composition that generates less volatile organic compounds (hereinafter sometimes referred to as VOCs) that are considered to be highly harmful to the human body. The present invention relates to a one-component moisture-curable urethane-based adhesive composition that is excellent in workability during adhesive coating.

One-component moisture-curing urethane adhesives containing a so-called urethane prepolymer having an isocyanate group at the molecular end are used for various applications.
These are adjusted to an appropriate viscosity / viscosity according to the application. For example, the viscosity / viscosity is adjusted so that the roll coatability is good when the adhesive is roll-coated, and the spatula (sprayed) is good when applied with a comb spatula. The
Various means can be considered as such a viscosity / viscosity adjusting means. In many cases, in order to lower the viscosity, an organic solvent such as toluene or ethyl acetate is added to the urethane adhesive to dilute. It was common to do.

  However, the organic solvent used to adjust the viscosity and viscosity along with the improvement of the airtightness of the house remains in the living space, and the “sick house” problem that poses a health hazard for residents becomes a social problem, especially the area where adhesive is used There has been a strong demand for low VOC for large floor adhesives.

  Therefore, the present inventors have proposed a safe one-part moisture-curing urethane-based adhesive that has a low volatility as a viscosity modifier and has reduced adverse effects on the human body and the environment (Patent Documents 1 and 2). ).

JP 2006-022298 A JP 2008-115328 A

  As a conventional definition of a volatile organic substance, there is a provision in WHO (World Health Organization) that “a compound having a boiling point of 260 ° C. or less is regarded as a volatile organic compound (VOC)”. However, due to the recent legal regulations, as stricter regulations than WHO, which is defined simply by the boiling point of the compound, volatile organic compounds (VOC), formaldehyde and other carbonyls of building materials are defined by JIS A 1901: 2003. In the “Compound Emission Measurement Test—Small Chamber Method”, the presence or absence of VOC is determined based on the actual measurement value.

Diluent that does not correspond to VOC in “Volatile organic compound (VOC), formaldehyde and other carbonyl compound emission measurement test for building materials-small chamber method” prescribed in JIS A 1901: 2003 When used as a viscosity modifier for a system adhesive, there is a problem that it is difficult to adjust to an appropriate viscosity, and it is difficult to use in applications where the adhesive is applied to the entire surface using a comb spatula. This is considered to be because the low molecular weight component which has been present in a minute amount in the viscosity modifier has been completely eliminated by a stricter regulation based on the actually measured value.
Even if a low viscosity can be achieved, there is an unevenness called unevenness on the ground in applications where the application is applied with a comb spatula. There was a possibility that problems such as poor adhesion would occur. In addition, the function of the adhesive is sufficiently achieved if the viscosity is low and the texture of the comb is good, but if the adhesive is viscous enough to pull the thread, the site often becomes soiled with the adhesive during work. Therefore, it has been desired to have a low viscosity, good comb-like texture, and good adhesive sharpness.

  The object of the present invention is to use a diluent that does not fall under VOC in the “Volatile Organic Compound (VOC), Formaldehyde and Other Carbonyl Compound Emission Measurement Test for Building Materials—Small Chamber Method” stipulated in JIS A 1901: 2003. On the other hand, it is possible to obtain a moisture-curing urethane-based adhesive that can be adjusted to an appropriate viscosity and that has a good texture and sharpness on the comb lines. Furthermore, one-part moisture-curing type that can provide not only good workability but also adhesion and floor squealing prevention properties when used in floor construction applications including floor heating applications, where application work is performed using a comb spatula. It is to obtain a urethane-based adhesive composition.

  In order to solve such problems, the present inventors have found that the above-mentioned problems can be solved by using a specific filler and additive as a result of intensive studies, and have completed the present invention. . The present invention comprises the following first to third inventions.

That is, the first invention is a urethane prepolymer (A), a filler (B), an additive (C), a dilution obtained by a reaction of a polyol having two or more active hydrogens at the molecular terminal with a polyisocyanate compound. A moisture-curing urethane-based adhesive containing a component (D) that does not correspond to a volatile organic substance in a small chamber method test defined in JIS A 1901: 2003 as an agent, and the filler (B) is heavy The present invention relates to a one-component moisture-curable urethane-based adhesive composition characterized by being a filler obtained by subjecting calcium carbonate to a surface treatment.
By using a filler that is surface-treated with heavy calcium carbonate, it can be adjusted to an appropriate viscosity while using a diluent that does not correspond to VOC, and moisture curing with excellent creaking and sharpness of combs is possible. A type urethane adhesive can be obtained.

The second invention relates to the one-component moisture-curable urethane-based adhesive composition according to the first invention, wherein the additive (C) contains a polyethylene fiber.
By including polyethylene fiber as an additive, it is possible to achieve both the texture of the comb and the sharpness.

The third invention further relates to a one-component moisture-curable urethane adhesive composition according to the second invention, wherein the additive (C) contains silica.
Furthermore, when the additive (C) contains silica, it is possible to improve both the texture of the comb and the sharpness.

  If the one-component moisture-curing urethane adhesive composition according to the present invention is used, the “emission measurement test for volatile organic compounds (VOC), formaldehyde and other carbonyl compounds in building materials” defined in JIS A 1901: 2003— While using a diluent that does not correspond to VOC in the “small chamber method”, it is possible to obtain a moisture-curing urethane-based adhesive that can be adjusted to an appropriate viscosity and that has a good comb texture and sharpness. In addition, it is possible to obtain a one-component moisture-curing urethane adhesive composition that can impart not only good workability but also adhesiveness and anti-flooring property.

  Hereinafter, embodiments for carrying out the present invention will be described in detail. In addition, this invention is not limited only to these illustrations, Of course, a various change can be added in the range which does not deviate from the summary of this invention.

The one-component moisture-curable urethane-based adhesive composition of the present invention includes a urethane prepolymer (A) and a filler (B) obtained by a reaction between a polyol having two or more active hydrogens at the molecular terminals and a polyisocyanate compound. , An additive (C), and a component (D) that does not correspond to a volatile organic substance in a small chamber method test defined in JIS A 1901: 2003 as an additive.
Hereafter, each element which comprises the one-component moisture hardening type urethane type adhesive composition in this invention is demonstrated in detail.

[Urethane prepolymer (A)]
As the urethane prepolymer (A) in the present invention, a conventionally known urethane prepolymer can be used. A conventionally known urethane prepolymer has an active isocyanate group at the molecular end obtained by a reaction of a compound having two or more active hydrogens at the molecular end with a polyisocyanate compound. As the compound having two or more active hydrogens at the terminal, a bifunctional or higher polyol having a molecular weight of about 100 to 20,000 is used, and these may be properly used depending on the purpose of use and performance. As the polyol, polyether type polyol, polyester type polyol, polyolefin polyol, etc. can be used alone or in combination of two or more.

  Examples of polyether type polyols include diols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, and bisphenol A. , Triols such as trimethylolethane, trimethylolpropane, glycerin, sorbitol, etc., and further, ethylene oxide in the presence of one or more amines such as ammonia, ethylenediamine, urea, monomethyldiethanolamine, monoethyldiethanolamine, Examples thereof include random or block copolymers obtained by ring-opening polymerization of propylene oxide, butylene oxide, styrene oxide, etc., and mixtures thereof.

  Polyester type polyols include, for example, polymers obtained by polycondensation of dicarboxylic acids such as maleic acid, fumaric acid, adipic acid, sebacic acid, phthalic acid or the like and the above diols alone or mixtures, ε-caprolactone, valero. Examples thereof include ring-opening polymers such as lactones, and active hydrogen compounds having two or more active hydrogens such as castor oil.

  Examples of the polyolefin type polyol include polybutadiene polyol, polyisoprene polyol and hydrogenated products thereof.

  A conventionally known polyisocyanate compound is also used as the polyisocyanate compound that reacts with the compound having two or more active hydrogens at the molecular ends to form a urethane prepolymer. As a conventionally known polyisocyanate compound, a diisocyanate compound or other polyisocyanate compounds can be used. As the diisocyanate compound, for example, an aliphatic diisocyanate compound, an alicyclic diisocyanate compound, an araliphatic diisocyanate compound, an aromatic diisocyanate compound, and the like can be used. Specific examples thereof will be given below.

  Aliphatic diisocyanate compounds: trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2 4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanate methyl caproate, and the like.

  Alicyclic diisocyanate compounds: 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, 4,4'-methylenebis (cyclohexyl) Isocyanate), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, isophorone diisocyanate and the like.

  Aroaliphatic diisocyanate compounds: 1,3- or 1,4-xylylene diisocyanate or mixtures thereof, ω, ω'-diisocyanate-1,4-diethylbenzene, 1,3- or 1,4-bis (1-isocyanate) -1-methylethyl) benzene or a mixture thereof.

  Aromatic diisocyanate compounds: m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4- or 2,6-tolylene diisocyanate 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate, and the like.

  Examples of the polyisocyanate compound excluding the diisocyanate compound include aliphatic, alicyclic, araliphatic, and aromatic polyisocyanate compounds. Specific examples thereof will be given below.

  Aliphatic polyisocyanate compounds: lysine ester triisocyanate, 1,4,8-triisocyanate octane, 1,6,11-triisocyanate undecane, 1,8-diisocyanate-4-isocyanate methyloctane, 1,3,6-tri Isocyanate hexane, 2,5,7-trimethyl-1,8-diisocyanate-5-isocyanate methyloctane, and the like.

  Alicyclic polyisocyanate compounds: 1,3,5-triisocyanatecyclohexane, 1,3,5-trimethylisocyanatecyclohexane, 3-isocyanatemethyl-3,3,5-trimethylcyclohexylisocyanate, 2- (3-isocyanatepropyl) -2,5-di (isocyanatomethyl) -bicyclo [2,2,1] heptane, 2- (3-isocyanatopropyl) -2,6-di (isocyanatomethyl) -bicyclo [2,2,1] heptane, 3- (3-Isocyanatopropyl) -2,5-di (isocyanatemethyl) -bicyclo [2,2,1] heptane, 5- (2-isocyanatoethyl) -2-isocyanatomethyl-3- (3-isocyanatopropyl) ) -Bicyclo [2,2,1] heptane, 6- (2-isocyanate) Nateethyl) -2-isocyanatomethyl-3- (3-isocyanatopropyl) -bicyclo [2,2,1] heptane, 5- (2-isocyanatoethyl) -2-isocyanatomethyl-2- (3-isocyanatopropyl)- Bicyclo [2,2,1] heptane, 6- (2-isocyanatoethyl) -2-isocyanatomethyl-2- (3-isocyanatopropyl) -bicyclo [2,2,1] heptane, and the like.

  Aro-aliphatic polyisocyanate compound: 1,3,5-triisocyanate methylbenzene and the like.

  Aromatic polyisocyanate compounds: triphenylmethane-4,4 ′, 4 ″ -triisocyanate, 1,3,5-triisocyanatebenzene, 2,4,6-triisocyanatotoluene, 4,4′-diphenylmethane-2, 2 ', 5,5'-tetraisocyanate and the like.

  When yellowing is a problem when using these polyisocyanate compounds, it is preferable to use aliphatic, cycloaliphatic, and araliphatic polyisocyanates, which are usually blended in these polyols and isocyanate compounds. If BHT (dibutylhydroxytoluene / antioxidant) is not blended, the total VOC emission can be further reduced. This is because these decomposition products may be detected as VOC components.

The method for synthesizing the urethane prepolymer may be a conventionally known method. For example, in a closed reaction kettle equipped with a stirrer, condenser, vacuum dehydration device, and nitrogen stream device, a compound having two or more active hydrogens at the end, such as polyols, is charged and dehydrated under reduced pressure, and then an isocyanate compound is blended into nitrogen. The reaction is carried out at 70 to 100 ° C. for 3 to 8 hours under an air flow to obtain a urethane composition containing a urethane prepolymer. At this time, the molar ratio of NCO groups to OH groups is NCO / OH = 1.2 or more, and the NCO mass% in the urethane prepolymer is NCO% = 1-20% (most preferably 2-15% ) Is preferable. When NCO mass% is high, the adhesive strength is also improved, but foaming during curing increases, and the cured film tends to become brittle. On the other hand, when the NCO mass% is low, foaming is reduced, but the viscosity of the prepolymer is high and it tends to be difficult to ensure the workability of the adhesive.
Moreover, since the unreacted polyisocyanate compound exists, so that the ratio of NCO / OH exceeds 2.0, the viscosity of a urethane prepolymer will become low by these dilution effects. In order to obtain desired performance, two or more kinds of urethane prepolymers may be mixed and used, or the polyisocyanate compound may be added to the urethane prepolymer by post-addition.

[About filler (B)]
The filler (B) in the present invention is not particularly limited as long as it can impart an appropriate viscosity and viscosity, and the comb spatula is good, but the surface treatment is particularly applied to heavy calcium carbonate. The applied filler is preferred. In this case, heavy calcium carbonate refers to finely ground crystalline limestone and classified.
Commercially available fillers obtained by subjecting heavy calcium carbonate to surface treatment include SCPE-2315 (manufactured by Sankyo Seimitsu Co., Ltd./trade name), Snowlite SSS, MC-E20 (manufactured by Maruo Calcium Co., Ltd./trade name). Etc.

  Although the compounding quantity of the filler (B) with respect to a urethane prepolymer (A) is arbitrary, For example, about 10-300 mass parts with respect to 100 mass parts of urethane prepolymers (A), Preferably it is about 25-200 mass parts. What is necessary is just to mix | blend. Since the filler may contain moisture that reacts with the isocyanate compound, the filler is added after the dehydration treatment so that the moisture content is 0.2% or less, preferably 0.1% or less. It is preferable to do this.

[Additive (C)]
The additive (C) in the present invention is blended for the purpose of imparting an appropriate viscosity and viscosity to the one-component moisture-curing urethane-based adhesive composition. Among these additives, polyethylene fibers and silica are preferable, and when these are blended, the coating workability, the texture of combs, the sharpness, and the cohesive strength of the adhesive film are further imparted.
Commercially available products can be used for these polyethylene fibers and silica. As a commercially available polyethylene fiber, Chemibest (trade name, manufactured by Mitsui Chemicals, Inc.) is preferably used. As commercially available products of silica, Aerosil # 200, R972, RY200 (manufactured by Nippon Aerosil Co., Ltd./trade name) and the like are preferably used.

  Although the compounding quantity of the additive (C) with respect to a urethane prepolymer (A) is arbitrary, For example, about 0.1-10 mass parts with respect to 100 mass parts of urethane prepolymers (A), Preferably 0.5- What is necessary is just to add and mix about 5 mass parts.

[Diluent (D)]
The diluent (D) in the present invention is blended for the purpose of reducing the viscosity of the one-component moisture-curing urethane-based adhesive composition by a diluting action, and is JIS A 1901: 2003. It does not fall under VOC in the prescribed “small chamber method test”.
Here, the “volatile organic compound (VOC), formaldehyde and other carbonyl compound emission measurement test for building materials—small chamber method” defined in JIS A 1901: 2003 will be described.
In this test method, an adhesive is applied on a stainless steel plate or a glass plate in a standard state (23 ± 2 ° C.) and cured to obtain a test specimen. The conditions at that time are as follows.
Application amount of adhesive: 300 ± 15 g / m ² Application area: 80 cm ² Curing time: 60 ± 10 minutes Curing environment: 23 ± 2 ° C.
The specimen after curing is left in a small chamber with a chamber capacity of 20 L, and the test is started under the following conditions.
Test temperature: 28 ± 1 ° C. Relative humidity: 50 ± 5% Ventilation frequency: 0.5 ± 0.05 times / h Sample load factor: 0.4 m ² / m ³ . It was cured for 7 days under these conditions, and VOC, formaldehyde and other carbonyl compounds were collected under the following conditions.
In the case of VOC Collection tube: TENAX-TA Air collection amount: 3.2L
Formaldehyde and other carbonyl compounds Collection tube: DNPH cartridge Air collection volume: 10L
The collected VOC was measured using a gas chromatograph equipped with a mass spectrometer by attaching a collection tube to a heat desorption device, desorbing the VOC by heating.
In the case of formaldehyde and other carbonyl compounds, the carbonyl compound DNPH derivative in the DNPH cartridge was measured by using a high performance liquid chromatograph after dissolving and detaching with acetonitrile.
As a VOC judgment standard, a substance detected in a range from n-hexane to n-hexadecane analyzed by gas chromatography is designated as VOC, and here, a value obtained by converting to toluene using the sum of peak areas is shown. It was.

  As such a diluent (D), N-alkyl-2-pyrrolidone (wherein the alkyl group may be octyl group or more), 2,2,4-trimethyl-1,3-pentanediol isobutyrate 2-ethylhexanoate, 2,2,4-trimethyl-1,3-pentanediol di-2-ethylhexanoate, alkyl ester of ricinoleic acid (wherein the alkyl group has 1 or more carbon atoms), Dialkyl esters of adipic acid (wherein the alkyl group has 8 or more carbon atoms) and the like are preferably used.

  Although the compounding quantity of the diluent (D) with respect to a urethane prepolymer (A) is arbitrary, For example, about 1-100 mass parts with respect to 100 mass parts of urethane prepolymers (A), Preferably it is about 5-50 mass parts. What is necessary is just to mix | blend.

[Other ingredients]
The one-component moisture-curable urethane-based adhesive composition according to the present invention contains the urethane prepolymer (A), the filler (B), the additive (C), and the diluent (D). As long as the first object of the present invention (that is, obtaining a low VOC type adhesive) can be achieved, a conventionally known optional component may be contained. For example, heavy calcium carbonate, synthetic calcium carbonate, filler such as kaolin, clay, talc, silica sand, etc., colorant such as titanium oxide, carbon black, other dyes or pigments, tackifier, thickener, silane Optional components such as a coupling agent, a titanium coupling agent, a pigment dispersant, an antifoaming agent, and an ultraviolet absorber may be contained.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not limited to an Example. In the present invention, by selecting a specific diluent and filler, the viscosity can be adjusted to an appropriate viscosity while having performance equal to or higher than that of the conventional one, and the texture and sharpness of the comb are good. It should be construed that the present invention has found that a one-component moisture-curing urethane adhesive composition capable of imparting adhesiveness and anti-flooring property can be obtained.

[Example 1]
In a 2 L separable flask, 800 parts by mass of bifunctional polypropylene glycol (Mn = 4000), 200 parts by mass of trifunctional polypropylene glycol (Mn = 3000), and 470 parts by mass of 4,4′-diphenylmethane diisocyanate (MDI). The reaction product “urethane composition (a1)” containing a urethane prepolymer having an NCO mass% of 9% was prepared by charging and reacting at 90 ° C. for 3 hours under a nitrogen stream.
600 parts by mass of this urethane-based composition (a1), 250 parts by mass of NS # 100 (manufactured by Nitto Flour Chemical Co., Ltd.), which is heavy calcium carbonate, SCPE-2315 (which is a filler obtained by subjecting heavy calcium carbonate to surface treatment) Sankyo Seimitsu Co., Ltd.) 350 parts by weight, PTSI (manufactured by Nippon Soda Co., Ltd./p-toluenesulfonyl isocyanate) as 2 parts by weight, diluent DINA (manufactured by Taoka Chemical Co., Ltd./diisononyl adipate) 80 parts by weight, 10 parts by weight of DBS (manufactured by Toyokuni Seiyaku Co., Ltd./dibutyl sebacate), which is also a diluent, is placed in a 2 L planetary mixer and stirred for 40 minutes under reduced pressure to form a one-part moisture-curing urethane adhesive composition. Got.

[Example 2]
Neither polypropylene glycol nor 4,4′-diphenylmethane diisocyanate used in Example 1 was blended with BHT (dibutylhydroxytoluene / antioxidant), and NCO mass% in the same manner as in Example 1. A reaction product “urethane-based composition (a2)” containing a urethane prepolymer having a content of 9% was obtained.
A one-component moisture-curable urethane-based adhesive composition was obtained in the same manner as in Example 1 except that this urethane-based composition (a2) was used.

[Example 3]
Example 1 except that 3 parts by weight of Chemibest FDSS-2 (manufactured by Mitsui Chemicals), which is a polyethylene fiber, was added to 1292 parts by mass of the one-component moisture-curable urethane-based adhesive composition obtained in Example 2 In the same manner as in No. 2, a one-component moisture-curable urethane adhesive composition was obtained.

[Example 4]
Example 3 is the same as Example 3 except that 5 parts by weight of Aerosil # 200 (manufactured by Nippon Aerosil Co., Ltd.), which is silica, is added to 1295 parts by mass of the one-component moisture-curable urethane-based adhesive composition obtained in Example 3. A one-component moisture-curable urethane-based adhesive composition was obtained in the same manner.

[Comparative Example 1]
Example 2 except that instead of the surface-treated heavy calcium carbonate, Searets 200 (manufactured by Maruo Calcium Co., Ltd./primary particle size (by electron microscope observation) 0.07 μm), which is a surface-treated synthetic calcium carbonate, was used. A one-component moisture-curable urethane-based adhesive composition was obtained in the same manner.

[Comparative Example 2]
Example 4 is different from Example 4 except that NS # 100, which is heavy calcium carbonate, is changed to 350 parts by mass (that is, NS # 100 is 600 parts by mass in total) instead of the filler obtained by surface treatment of heavy calcium carbonate. A one-component moisture-curable urethane-based adhesive composition was obtained in the same manner.

[Comparative Example 3]
The same method as in Example 2 except that the diluents (DINA and DBS) used in Example 1 were changed to 90 parts by mass of Isopar H (ExxonMobil Corp./containing the VOC component in the small chamber method test). A one-component moisture-curable urethane-based adhesive composition was obtained.

  For the one-component moisture-curing urethane adhesive compositions obtained in Examples 1 to 4 and Comparative Examples 1 to 3, application workability, adhesive ridges, sharpness, and adhesive cohesive force measurement are performed by the following methods. And the amount of VOC emission was measured.

[Coating workability]
One-part moisture-curing urethane system with a comb spatula (E-8 type comb spatula manufactured by Konishi Co., Ltd.) in an atmosphere of 5 ° C. so that the coating amount is about 550 g / m ^{2 on the} slate plate. The adhesive composition was applied. The adhesive used was allowed to stand at 5 ° C. for 24 hours or more. From the resistance of the comb spatula at that time, the evaluation was made in the following three stages.
(Evaluation criteria)
○: The resistance of the comb spatula when applying the adhesive is small, and it can be said that the coating workability is good.
(Triangle | delta): It can be said that the resistance feeling of the comb spatula at the time of application | coating of an adhesive agent is somewhat large, and application | coating workability | operativity is inadequate.
X: The resistance of the comb spatula when applying the adhesive is very large, and it can be said that the coating workability is poor.
In practice, it can be determined that it can be used without any problem if it is ◯ or Δ.

[Stick standing of adhesive]
One-part moisture-curing urethane system on a slate plate with a comb spatula (E-8 type comb spatula manufactured by Konishi Co., Ltd.) in an atmosphere of 23 ° C. so that the coating amount is about 550 g / m ^2. The adhesive composition was applied. Comb spatula standing at that time was evaluated in the following three stages.
(Evaluation criteria)
◯: Comb spatula stands well and can be said to be able to cope with the unevenness of the site.
△: Comb spatula stands slightly bad and may not be able to cope with unevenness at the site.
×: Comb spatula is badly standing and cannot cope with the unevenness of the site.
In practice, it can be determined that it can be used without any problem if it is ◯ or Δ.

[Adhesive sharpness]
One-part moisture-curing urethane system on a slate plate with a comb spatula (E-8 type comb spatula manufactured by Konishi Co., Ltd.) in an atmosphere of 23 ° C. so that the coating amount is about 550 g / m ^2. The adhesive composition was applied. The sharpness of the adhesive at that time was evaluated in the following four stages.
(Evaluation criteria)
A: The adhesive is very clean and does not pollute the site.
○: The adhesive has good sharpness and is difficult to stain on site.
(Triangle | delta): The sharpness of an adhesive agent is a little bad, and it may stain on-site.
X: The adhesive is not sharp and soils the site.
In practice, it can be determined that there is no problem if it is ◎, ○ or Δ.

[Cohesive strength of adhesive]
The test was conducted by a method according to JIS A 5536. In this case, the adherend was a panel / slate plate, and the evaluation was as follows.
(Evaluation criteria)
○: Adhesive strength is 1 N / mm ² or more, or material destruction of the adherend.
(Triangle | delta): Although adhesive strength is 1 N / mm < ² > or more, the material destruction of a to-be-adhered body is not seen.
X: Adhesive strength is 1 N / mm < ² > or less, or material destruction of the adherend is not observed.
In practice, it can be determined that it can be used without any problem if it is ◯ or Δ.

[VOC emission]
Tested according to JIS A 1901: 2003 “Measurement of Volatile Organic Compound (VOC), Formaldehyde and Other Carbonyl Compound Emission Measurements for Building Materials-Small Chamber Method”, and TVOC Emission after 7 Days The emission rate was measured. The evaluation at that time was as follows.
(Evaluation criteria)
◎: Both emission amount and emission rate are 50 or less ○: Both emission amount and emission rate are 150 or less △: Both emission amount and emission rate are 400 or less ×: Both emission amount and emission rate are 400 or more

Table 1 shows the composition of the one-component moisture-curing urethane adhesive composition and the results of the evaluation test in Examples and Comparative Examples.
From the results shown in the table, the one-component moisture-curing urethane adhesive composition (Examples 1 to 4) according to the present invention is excellent in coating workability, and is free of adhesive eruption, adhesive sharpness, and adhesive properties. It can be seen that both the cohesive force and the amount of VOC emission are at a level where there is no practical problem.
On the other hand, it can be seen that the one-component moisture-curable urethane-based adhesive compositions of Comparative Examples 1 to 3 lacking the constituent requirements of the present invention have practical problems in any of the evaluation test items.

  The one-component moisture-curable urethane adhesive composition according to the present invention is adjusted to an appropriate viscosity while using a diluent that does not correspond to VOC in the “small chamber method test” defined in JIS A 1901: 2003. It is possible to provide a one-component moisture-curing urethane-based adhesive composition that not only has excellent texture and sharpness on the comb lines, but can also provide adhesion and anti-flooring properties. Probability is high.

Claims (2)

Urethane prepolymer (A), filler (B), additive (C) obtained by reaction of a polyol having two or more active hydrogens at the molecular terminals and a polyisocyanate compound, as a diluent in JIS A 1901: 2003 A moisture-curing urethane-based adhesive containing a component (D) that does not correspond to a volatile organic substance in a specified small chamber method test,
A one-component moisture-curable urethane-based adhesive composition, wherein the filler (B) is a filler obtained by subjecting heavy calcium carbonate to a surface treatment. The one-component moisture-curable urethane-based adhesive composition according to claim 1, wherein the additive (C) contains polyethylene fiber and / or silica.