To produce a tacky agent containing a residual monomer in an amount of ≤0.2 wt.% as a solid content in a short time.
When a medicinal acrylic tacky agent is produced by polymerizing a monomer composition containing (meth)acrylic acid alkyl ester as a main component and containing N-vinyl-2-pyrrolidone(VP) in relatively large amount, polymerization reaction in a first step is carried out until polymerization ratio becomes ≥90% and then, polymerization reaction in a second step is carried out until residual amount of a radical polymerization initiator becomes ≤5 wt.% based on the charged amount at a temperature higher than a temperature of polymerization reaction in the first step and further, polymerization reaction in a third step is carried out by adding monomers other than VP of the monomer composition together with a radical polymerization initiator to a reaction product after polymerization reaction in the second step to reduce a residual amount of VP to the half or below of that before the polymerization reaction in the third step and reduce total residual amount of monomers other than VP to the half or below of the residual amount of VP and then, reaction product after finishing the polymerization reaction is dried in thin film state to evaporate the residual monomer.
TOO KAZUHIRO
AKEMI HITOSHI
| JPH05131022A | 1993-05-28 | |||
| JPH08103490A | 1996-04-23 | |||
| JPS60161917A | 1985-08-23 | |||
| JPH05131022A | 1993-05-28 | |||
| JPH08103490A | 1996-04-23 | |||
| JPS60161917A | 1985-08-23 |
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