Sustained-release grant medicine, sustained-release agricultural chemical and its manufacturing method null

摘要

PURPOSE:To obtain a slowly releasing agricultural chemical capable of continuously and slowly releasing the minimum amount of the active component necessary for the control of blight over a long period by attaching or fixing fine powder of a hydrophobic substance to the surface of solid particles of an active component of an agricultural chemical. CONSTITUTION:Fine powder of a hydrophobic substance (e.g., higher fatty acid, hydrophobic silica or hydrophobic synthetic polymer) is applied to the surface of solid particles of an active component of an agricultural chemical or the particles of the hydrophobic substance fine powder are fixed to the surface of the active component particle by thrusting the fine powder particles into the surface layer to obtain a slowly releasing agricultural chemical consisting of a center core composed of the active component of the agricultural chemical and an outer layer surrounding the center core and composed of the fine powder of the hydrophobic substance. The average particle diameter of the hydrophobic substance is =1/5 of that of the active component of the agricultural chemical. As an alternative method, individual particles of the hydrophobic substance fine powder attached or fixed to the surface of the particle of the active component of agricultural chemical are integrated with each other by impact force and/or frictional heat to obtain a slowly releasing agricultural chemical consisting of the center core of the active component of the agricultural chemical and a continuous coating layer of the hydrophobic substance surrounding the center core.