PROBLEM TO BE SOLVED: To provide a water-dispersible vaporized active substance sustained release product which is capable of releasing almost the entire quantity thereof at a constant release rate over a long period of time, and which has a low viscosity and adequate adhesion performance.SOLUTION: The water dispersion for the sustained release product includes polymer particles obtained by polymerizing an ethylenically unsaturated group-containing monomer (A), at least one hydrophilic substance (B) selected from the group consisting of surfactants, plasticizers and moisturizing agents and contained in a quantity of more than 0 and not more than 20 mass% with respect to the total quantity of the ethylenically unsaturated group-containing monomer (A), and a polyvinyl alcohol (C) having a degree of saponification which exceeds 82 mol.% and is contained in a quantity of more than 0% and not more than 30 mass% with respect to the total quantity of the ethylenically unsaturated group-containing monomer (A), and water. The viscosity of the dispersion at 25°C does not exceed 100 mPa s. The sustained release product contains the water dispersion and a vaporized active substance selected from the group consisting of pheromone substances, agricultural chemicals, fragrances, deodorizing agents and antibacterial agents.COPYRIGHT: (C)2013,JPO&INPIT【課題】長期間にわたり、一定の放出速度で、含有量ほぼ全量を放出することができ、低粘度かつ十分な付着性能を持った水分散型気化活性物質徐放製剤を提供する。【解決手段】エチレン性不飽和基含有単量体(A)を重合して得られる重合体粒子と、上記エチレン性不飽和基含有単量体(A)総量に対して0を超えて20質量%以下の、界面活性剤、可塑剤及び保湿剤からなる群から選択される少なくとも1種の親水性物質(B)と、上記エチレン性不飽和基含有単量体(A)総量に対して0を超えて30質量%以下のケン化度が82モル%を超えるポリビニルアルコール(C)と、水とを含有し、25℃の粘度が100mPa・s以下である徐放性製剤用水分散体を提供し、この水分散体と、フェロモン物質、農薬、芳香剤、消臭剤及び抗菌剤からなる群から選択される気化活性物質とを含有する徐放性製剤を提供する。【選択図】なし