Multilayer dissolvable solid article containing solid particles for making the same
AssigneeThe Procter & Gamble Company
InventorsCarl David MAC NAMARA, HongSing TAN, Robert Wayne GLENN, JR., Wenhu PANG, Kejing DU, Yuxiang LIU
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Abstract
A dissolvable solid article which can include multiple layers of flexible, dissolvable, porous sheets, in which a coating composition including solid particles is present on at least one internal surface of at least one sheet in said solid articles and a process for making such solid articles.
Claims20
A dissolvable solid article comprising two or more flexible, porous, dissolvable sheets, wherein each of said two or more sheets comprises a water-soluble polymer and a surfactant and is characterized by a Percent Open Cell Content of from about 80% to about 100% and an Overall Average Pore Size of from about 100 μm to about 2000 μm;
- and
- a coating composition comprising a non-aqueous liquid carrier, solid particles, and a thickening agent, wherein said composition comprises:
- a) from about 20% to about 80%, of said non-aqueous liquid carrier by total weight of said coating composition;
- b) from about 20% to about 60%, of said solid particles by total weight of said coating composition;
- c) from about 0.1% to about 30%, of said thickening agent by total weight of said coating composition;
- said solid particles comprise a bleaching agent, a bleach activator, or an anionic surfactant, said thickening agent comprises silica;
- and wherein said coating is present on at least one surface of at least one of said two or more sheets, provided that said coating composition is not on any of the outer surfaces of the dissolvable solid article.
The dissolvable solid article of claim 15, wherein said coating composition comprises a bleaching agent selected from the group consisting of a percarbonate salt, a perborate salt, a persulfate salt, or a combination thereof;
- and
- wherein each sheet within said second group of sheets comprises a bleach activator comprising tetraacetylethylenediamine, oxybenzene sulphonate, caprolactam;
- pentaacetate glucose, nitrile quaternary ammonium, imide bleach activator, or a combination thereof.
The process of claim 17, wherein said two or more flexible, porous, dissolvable sheets are provided by using the following steps:
- a) preparing a wet pre-mixture comprising said water-soluble polymer and said surfactant;
- b) aerating said wet pre-mixture to form an aerated wet pre-mixture;
- c) forming said aerated wet pre-mixture into a sheet having opposing first and second sides;
- and
- d) drying said formed sheet to make said two or more flexible, porous, dissolvable sheet.
The process of claim 18, wherein step d) is conducted for a duration from about 10 min to about 120 min, at a temperature from about 70° C. to about 200° C., along a heating direction that forms a temperature gradient decreasing from the first side to the second side of the formed sheet, wherein the heating direction is substantially opposite to the gravitational direction for more than half of the drying time.
The process of claim 19, wherein the wet pre-mixture has a viscosity of from 1,000 cps to 25,000 cps measured at 40° C. and 1 s−1, and/or the aerated wet pre-mixture has a density of from about 0.2 g/ml to about 0.6 g/ml.
Dependencies are inferred from the claim text.