PURPOSE: To provide the titled film-forming material having excellent film- forming properties and adhesion to hard tissues of an organism such as inorg. etc., by blending a polymer having carboxyl (anhydride) and hydrophobic groups with Ca(OH)2.

CONSTITUTION: A vinyl monomer (a) having carboxyl (anhydride) group and carboxylic ester group attached to neighboring carbon atoms respectively (e.g., maleic anhydride) is copolymerized with 40W90mol% of a vinyl monomer (b) having a hydrophobic group (e.g., styrene) in the presence of a polymn. initiator (e.g., benzoyl peroxide). If desired, the product is hydrolyzed to obtain a polymer (A) having carboxyl (anhydride) and hydrophobic groups, an acid value of 30W700 and an MW of 1,000W100,000. If desired, 1pt.wt. component A is dissolved or suspended in 1W100pts.wt. org. solvent (e.g., ethanol). The component A is blended with Ca (OH)2 in an amount of 0.1W5.0mol per mol of the carboxyl group of the component A or 1/2mol of anhydride group thereof. The components A and B are separately stored and blended with each other when used.