摘要:
A controlled release product is provided having a suppressed initial release period and a predetermined longevity. The product includes a particulate water soluble core material and a semi-permeable coating layer applied on the core material for controlling the release rate of the core material. The semi-permeable coating layer is formulated in accordance with the following equation to provide a release rate wherein initial release of core material from the product is suppressed so that less than about 15 weight percent of core material is released from the product within a 24 hour period after application of the product and wherein longevity of release, at ambient temperature, between the time of application and the time at which at least about 75 weight percent of the core material is released from the product is 60 days or less: WVTR = ϕ · δ π d 2 wherein: (i) WVTR is the water vapor transmission rate of the semi-permeable coating expressed in grams·μm/meters2·day; (ii) φ is the water diffusion rate (water flux) through the semi-permeable coating expressed in grams/day; (iii) δ is the thickness of the coating layer expressed in μm; and (iv) d is the average diameter of the particulate core material expressed in meters.
摘要:
A controlled release product is provided having a suppressed initial release period and a predetermined longevity. The product includes a particulate water soluble core material and a semi-permeable coating layer applied on the core material for controlling the release rate of the core material. The semi-permeable coating layer is formulated in accordance with the following equation to provide a release rate wherein initial release of core material from the product is suppressed so that less than about 15 weight percent of core material is released from the product within a 24 hour period after application of the product and wherein longevity of release, at ambient temperature, between the time of application and the time at which at least about 75 weight percent of the core material is released from the product is 60 days or less: WVTR = φ · δ π d 2 wherein: (i) WVTR is the water vapor transmission rate of the semi-permeable coating expressed in grams·&mgr;m/meters2·day; (ii) &phgr; is the water diffusion rate (water flux) through the semi-permeable coating expressed in grams/day; (iii) &dgr; is the thickness of the coating layer expressed in &mgr;m; and (iv) d is the average diameter of the particulate core material expressed in meters.
摘要:
Improved, solid water-soluble fertilizer (WSF) compositions are presented which comprise at least one acid (optionally nutritive) and at least one basic fertilizer component. In one or more embodiments of the present invention, the WSF compositions demonstrate improved solubility of one or more nutrients or additives in solution, do not require additional dissolution aids or anti-caking agents, demonstrate fast dissolution times, produce precipitate free solutions, are readily compounded without intermediate wetting or drying steps, do not generate gas, and demonstrate improved stability under typical usage conditions. Finally, the WSF compositions may be used in improved processes for the creation of stock solutions, optionally with cold water, and/or delivery of nutrients to plants.
摘要:
A coated triggered start product is formed from a particulate core material comprising at least one water soluble active constituent and at least one coating layer applied on the particulate core material. The coating layer causes the product to exhibit “lock-off” type release characteristics whereby release of the active constituent of the core material from the coated product is essentially completely suppressed until release is initiated by application of a trigger material to the coating layer. Processes for preparing and using such triggered start products are also provided.
摘要:
Improved, solid water-soluble fertilizer (WSF) compositions are presented which comprise at least one acid (optionally nutritive) and at least one basic fertilizer component. In one or more embodiments of the present invention, the WSF compositions demonstrate improved solubility of one or more nutrients or additives in solution, do not require additional dissolution aids or anti-caking agents, demonstrate fast dissolution times, produce precipitate free solutions, are readily compounded without intermediate wetting or drying steps, do not generate gas, and demonstrate improved stability under typical usage conditions. Finally, the WSF compositions may be used in improved processes for the creation of stock solutions, optionally with cold water, and/or delivery of nutrients to plants.