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:
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:
A controlled release fertilizer is provided which exhibits a Gaussian nutrient release rate pattern. The fertilizer composition includes a granular nutrient core material having a single layer coating of a substantially water-insoluble, uniform, substantially continuous polymer film thereon. Processes are also provided for producing the fertilizer compositions. Methods are also provided for treating plants with the fertilizer compositions.
摘要:
A controlled release fertiliser composition is provided having a fertiliser compound in a granular core with a coating applied on the core material. The fertiliser composition is structured to enable a cumulative release of fertiliser compound of less than 10% of the total weight of the fertiliser compound in the granular core within 30 days after exposure of the fertiliser composition to moisture and the coating consists of a single layer of a uniform, substantially continuous polymer film which is present on at least 90% of the granular core material A process is also provided for producing the fertiliser composition.
摘要:
The present invention relates to a solid water soluble fertilizer composition containing one or more fertilizer materials and a phosphate free, organic acid which is solid at ambient temperatures. The fertilizer materials include primary macro nutrients, secondary macro nutrients, micro nutrients and mixtures thereof. The organic acid has a water solubility of at least 10 g/l (at 25° C.) and an acidifying effect in the range of 0.5 to 1.3 g HCO3−/g acid. The acidifying effect is defined as the amount of HCO3− that can be transformed into H2CO3 per gram of acid and is calculated in accordance with the following formula: 61 n M w , acid wherein Mw,acid is the molecular weight of said acid and n represents the number of dissociation constants (i.e., pKa values) of the acid below the value of 6.35. The acid should be present in the composition in an amount sufficient to reduce the HCO3− level in water treated with the composition by between about 60-400 parts per million when applied to the water at a dosage of 1 gram per liter.
摘要:
Bodily tissue and structures may be protected using a fluid layer containing a mixture of chitosan and oxidized polysaccharide. The mixture forms a protective gel layer via in situ crosslinking. Compared to crosslinking using a low molecular weight aldehyde such as glutaraldehyde or genipin, oxidized polysaccharides appear to provide faster gelation while avoiding the use of potentially less bioacceptable low molecular weight aldehydes.
摘要:
Medical devices with polymer coatings designed to control the release of angiotensin-(1-7) receptor agonists from medical devices are disclosed. The present application also discloses providing vascular stents with angiotensin-(1-7) receptor agonist-containing controlled-release coatings. Methods for treating or inhibiting post-stent implantation restenosis as well as improving vascular endothelial function in patients are also provided.
摘要:
Chronic rhinosinusitis and other bacterial sinus conditions may be treated by applying a solvating system containing a surfactant to a bacterial biofilm in a nasal or sinus cavity, disrupting the biofilm, and applying a protective layer of a polymeric film-forming medical sealant.
摘要:
Medical devices with polymer coatings designed to control the release of bioactive agents in combination with angiotensin-(1-7) receptor agonists from medical devices are disclosed. Methods for treating or inhibiting post-stent implantation restenosis as well as improving vascular endothelial function in patients are also provided.