Stable peracid bleaching compositions: organic peracid, magnesium sulfate and controlled amounts of water
Reference Number: N 03-07
Inventors: Coyne, Thomas S.; Haendler, Blanca L.; Klapprott, Daniel H.; Mitchell, Frances E.; Steichen, Dale S.; Thompson, Suzanne M.
Invention SummaryThe present invention relates to organic diperacid based bleaching products and in particular to granular organic diperacid bleaching products for household use. In one embodiment, the invention provides a stabilized granular peracid bleach composition, in which the amount of water present in the bleach granules is carefully controlled to maximize stability of the granules.
The invention provides in a further embodiment a peracid and enzyme bleaching composition wherein the active components are an oeganic diperacid preferably, diperoxydodecanedioic acid, and an enzyme, generally speaking, a protease. Additional components are present in the product to maximize the active oxygen available for bleaching purposes when placed into aqueous solution, to minimize the decomposition of the peracid while on the shelf, and to reduce or cover the objectionable odor of the diperacid.
Thus, in both embodiments of the invention, the improved product is prepared by carefully controlling the moisture content of the peracid granule with respect to the amount of exotherm control in order to improve both peracid and enzyme stability.
More specifically, the bleaching product is based upon organic diperacids, most preferably diperoxydodecanedioic acid. An exotherm control agent, preferably a combination of Na.sub.2 SO.sub.4 and MgSO.sub.4 in the hydrated form, is admixed with the diperacid in critical amounts to optimize solubility and thus maximize the active oxygen yield when the diperacid is used in aqueous media, yet affords exotherm Protection. The water level present in the peracid/exotherm control granule of the composition is also carefully adjusted so that minimum destabilization of the diperacid and enzyme is brought about by its presence, but at the same time, the exotherm control effects are maintained.
The diperacid and its stabilizing agents are prepared as a discrete granular component of the total composition.
It is an object of the invention to provide a diperacid bleach composition having maximum active oxygen yield in solution but retaining necessary exotherm control properties prior to use.
It is another object of the invention to provide diperacid based bleaching product wherein the moisture content of the bleach and exotherm control agent is regulated to minimize deterioration of the enzyme and peracid during the product shelf-life but retaining effective exotherm control of the product and soil and stain removal potency.
It is yet another object of this invention to provide a stabilized peracid and enzyme bleaching composition.