One-component moisture-curable urethane composition and method for producing same

Abstract

The present technology is to provide a one-part moisture-curable polyurethane composition having excellent adhesion to an adherend (coated plate), and a method for producing such a composition. The present technology is a one-part moisture-curable urethane composition including a preliminary composition obtained by mixing a urethane prepolymer, an aliphatic isocyanate A, and an aminosilane compound B, and a catalyst; and a method for producing such a composition.

The invention claimed is: 
     
       1. A one-part moisture-curable urethane composition including:
 a preliminary composition obtained by mixing a urethane prepolymer, an aliphatic isocyanate A, and an aminosilane compound B, and 
 a catalyst, wherein the catalyst contains N, N-dimethylaminoethylmorpholine and products formed by reacting 1,3-diacetoxy-1,1,3,3-tetrabutyl-distannoxane with ethyl silicate in a molar ratio of 1:0.8 to 1.2. 
 
     
     
       2. The one-part moisture-curable urethane composition according to  claim 1 , wherein the urethane prepolymer is obtained by reacting polypropylene glycol with diphenylmethane diisocyanate. 
     
     
       3. The one-part moisture-curable urethane composition according to  claim 1 , wherein the aliphatic isocyanate A is at least one type of aliphatic isocyanate-modified product a selected from the group consisting of reaction products of a polyol having tri- or higher functionality and an aliphatic polyisocyanate, allophanates of aliphatic polyisocyanate, isocyanurates of aliphatic polyisocyanate, and biurets of aliphatic polyisocyanate. 
     
     
       4. The one-part moisture-curable urethane composition according to  claim 1 , wherein the aminosilane compound B contains, in each molecule, an alkoxysilyl group and a nitrogen atom to which an aromatic ring and a hydrogen atom are bonded. 
     
     
       5. The one-part moisture-curable urethane composition according to  claim 4 , wherein the alkoxysilyl group is a methoxysilyl group or an ethoxysilyl group. 
     
     
       6. The one-part moisture-curable urethane composition according to  claim 1 , wherein, per 100 parts by weight of the urethane prepolymer,
 an amount of the aliphatic isocyanate A is from 0.8 to 10 parts by mass, and 
 an amount of the aminosilane compound B is from 0.1 to 4 parts by mass. 
 
     
     
       7. The one-part moisture-curable urethane composition according to  claim 1 , wherein the catalyst further contains at least one type selected from the group consisting of dibutyltin acetylacetate, and dimorpholinodiethyl ether. 
     
     
       8. The one-part moisture-curable urethane composition according to  claim 7 , wherein the catalyst contains products formed by reacting 1,3-diacetoxy-1,1,3,3-tetrabutyl-distannoxane with ethyl silicate in a molar ratio of 1:0.8 to 1.2,
 dibutyltin acetylacetate, 
 dimorpholinodiethyl ether, and 
 N, N-dimethylaminoethylmorpholine. 
 
     
     
       9. The one-part moisture-curable urethane composition according to  claim 8 , wherein an amount of the organotin catalyst is from 0.0005 to 0.3 parts by mass per 100 parts by mass of the urethane prepolymer. 
     
     
       10. The one-part moisture-curable urethane composition according to  claim 8 , wherein an amount of the dimorpholinodiethyl ether is from 0.004 to 1.2 parts by mass per 100 parts by mass of the urethane prepolymer. 
     
     
       11. The one-part moisture-curable urethane composition according to  claim 8 , wherein an amount of the N, N-dimethylaminoethylmorpholine is 1 part by mass or less per 100 parts by mass of the urethane prepolymer. 
     
     
       12. The one-part moisture-curable urethane composition according to  claim 1 , wherein the preliminary composition further contains a filler. 
     
     
       13. The one-part moisture-curable urethane composition according to  claim 12 , wherein the filler is at least one selected from the group consisting of carbon blacks and white fillers. 
     
     
       14. The one-part moisture-curable urethane composition according to  claim 1 , wherein the preliminary composition further contains a plasticizer. 
     
     
       15. A method for producing a one-part moisture-curable urethane composition, the method comprising:
 a mixing step 1 of obtaining a preliminary composition by mixing a urethane prepolymer, an aliphatic isocyanate A, and an aminosilane compound B; and 
 a mixing step 2 of producing the one-part moisture-curable urethane composition described in  claim 1  by mixing the preliminary composition and a catalyst. 
 
     
     
       16. The method for producing a one-part moisture-curable urethane composition according to  claim 15 , wherein at least one selected from the group consisting of fillers and plasticizers is further used in the mixing step 1. 
     
     
       17. The one-part moisture-curable urethane composition according to  claim 4 , wherein the alkoxysilyl group is an ethoxysilyl group.