Hydrophilic ester polyurethane foams
AssigneeFoamex L.P.
InventorsSharon Free, Joseph Bertolini, Chiu Chan, Marc Albero
Life of this patent
Estimating the term…
Abstract
An ester polyurethane foam is prepared by reacting one or a mixture of hydrophilic polyester polyols with one or more isocyanates and a cell opening surfactant. The cured foam does not require post-foaming processing to achieve a water absorption rate of at least 20 pounds of water per square foot per minute, preferably at least 25 pounds of water per square foot per minute. The foam may be bonded to a substrate to form an absorbent article, such as a sponge, mop head, or a medical or industrial wipe.
Claims21
A method for making a hydrophilic polyester polyurethane foam, comprising:
- (a) forming a polyurethane foam by mixing together the following components:
- (i) 100 parts by weight of a polyol or mixture of polyols, wherein at least about 40 parts by weight of such polyol or mixture of polyols comprises a hydrophilic polyester polyol with an hydroxyl number of 40 to 100;
- (ii) at least about 30 parts by weight, based on 100 parts polyol, of an isocyanate, wherein the isocyanate index is from 60 to 110;
- and
- (iii) up to about 3.0 parts by weight, based on 100 parts polyol, of a cell opening surfactant;
- wherein the hydrophilic polyester polyurethane foam has a water absorption rate of at least 20 pounds of water per square foot per minute.
A method for making an absorbent article, comprising:
- (a) forming a hydrophilic polyurethane foam by mixing together the following components:
- (i) 100 parts by weight of a polyol or mixture of polyols, wherein at least about 40 parts by weight of such polyol or mixture of polyols comprises a hydrophilic polyester polyol with an hydroxyl number of 40 to 100;
- (ii) at least about 30 parts by weight, based on 100 parts polyol, of an isocyanate, wherein the isocyanate index is from 60 to 110;
- and
- (iii) up to about 3.0 parts by weight, based on 100 parts polyol, of a cell opening surfactant;
- wherein the hydrophilic polyester polyurethane foam has a water absorption rate of at least 20 pounds of water per square foot per minute;
- and
- (b) laminating the hydrophilic polyester polyurethane foam to a substrate.
Dependencies are inferred from the claim text.