Patent ID: 8273847

Claim:
A medical adhesive which comprises a hydrophilic urethane prepolymer (UP) obtained by reacting a fluorine-containing aliphatic diisocyanate (A 11 ) having 5 to 12 carbon atoms and a polyol component (B) having a hydrophilic polyol (B 1 ), and a phenolic radical scavenger (PRS), and the fluorine-containing aliphatic diisocyanate (A 11 ) is a diisocyanate represented by OCN—CH 2 —Rf—CH 2 —NCO, wherein Rf represents a perfluoroalkylene group having 3 to 10 carbon atoms, which optionally contains an ether bond, a content of oxyethylene groups in the polyol component (B) is 30 to 100% by weight based on the weight of oxyalkylene groups in (B), the hydrophilic polyol (B 1 ) is a polyether polyol (B 1 - 1 ), the polyether polyol (B 1 - 1 ) is an adduct of ethylene oxide, or a co-adduct of ethylene oxide and alkylene oxide having 3 to 8 carbon atoms to a compound having at least two active hydrogens, an equivalent weight of the hydroxyl group in the hydrophilic polyol (B 1 ) is from 50 to 5,000, the phenolic radical scavenger (PRS) is at least one selected from the group consisting of 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,2′-methylenebis (4-methyl-6-t-butylphenol), 2,2′-methylenebis (4-ethyl-6-t-butylphenol), 4,4′-butylidenebis (3-methyl-6-t-butylphenol), 4,4′-thiobis (3-methyl-6-t-butylphenol), 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 3,9-bis[1,1-dimethyl-2-[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyl]ethyl]2,4,8,10-tetraoxaspiro[[5,5]]undecane, tetrakis-[methylene-3-(3′,5′-di-t-butyl-4′-hydroxyphenyl)propionate]methane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, bis[3,3′-bis-(4′-hydroxy-3′-t-butylphenyl)butylic acid]glycol ester, and 1,3,5-tris(3′,5′-di-t-butyl-4′-hydroxybenzyl)-sec-triazine-2,4,6-(1H,3H,5H) trion, and a content of sodium, potassium and magnesium is between 0 to less than 0.04 mmol/kg based on the weight of (UP).