Porous, absorbent macrostructures of bonded absorbent particles surface crosslinked with cationic amino-epichlorohydrin adducts
AssigneeThe Procter & Gamble Company
InventorsEbrahim Rezai, Frank H. Lahrman, Toshiaki Iwasaki
Life of this patent
Estimating the term…
Abstract
Porous, absorbent macrostructures that, upon contacting liquids such as water or body exudates (e.g., urine), swell and imbibe such liquids, and are useful in absorbent articles such as diapers, adult incontinence pads, and sanitary napkins are disclosed. These porous macrostructures comprise bonded absorbent particles that are surface crosslinked with cationic, preferably polymeric, amino-epichlorohydrin adducts.
Claims33
A porous, absorbent macrostructure comprising an interparticle bonded aggregate comprising:
- (i) a multiplicity of precursor particles bonded to each other at the surface thereof and comprising a substantially water-insoluble, absorbent, hydrogel-forming, polymer material having anionic functional groups, and
- (ii) a cationic amino-epichlorohydrin adduct reacted with said polymer material at said surface of said precursor particles and in an amount sufficient to cause effective surface crosslinking;
- said interparticle bonded aggregate having pores between adjacent precursor particles, said pores being interconnected by intercommunicating channels so as to form a liquid permeable macrostructure, the circumscribed dry volume of the macrostructure being greater than about 0.008 mm.sup.3.
A flexible, porous, absorbent sheet having a thickness of at least about 0.2 mm and a density of from about 0.8 to about 1.1 g/cc, and comprising an interparticle bonded aggregate comprising:
- (i) a multiplicity of precursor particles having a mass average particle size less than about 300 microns bonded to each other at the surface thereof and comprising a substantially water-insoluble, absorbent, hydrogel-forming, polymer material having carboxy groups;
- (ii) a cationic polymorphic amino-epichlorohydrin resin in an amount of from about 0.1 to about 5 parts by weight, per 100 parts by weight of said precursor particles, said cationic polymeric resin being reacted with said polymer material at said surface of said precursor particles so as to form ester crosslink bonds;
- (iii) a plasticizer in an amount of from about 5 to about 60 parts by weight, per 100 parts by weight of said precursor particles;
- said interparticle bonded aggregate having pores between adjacent precursor particles, said pores being interconnected by intercommunicating channels so as to form a liquid permeable sheet, the circumscribed dry volume of the sheet being greater than about 500 mm.sup.3.
Dependencies are inferred from the claim text.