Absorbent structures comprising coated super-absorbent polymer particles

• US 20060240229A1
• Filed: 06/26/2006
• Published: 10/26/2006
• Est. Priority Date: 06/30/2004
• Status: Active Grant

• Current Assignee: Bruno Johannes Ehrnsperger, Heike Opper, Udo Friedel Schoenborn
• Original Assignee: Bruno Johannes Ehrnsperger, Heike Opper, Udo Friedel Schoenborn
• Inventors: Ehrnsperger, Bruno Johannes, Opper, Heike, Schoenborn, Udo Friedel
• Granted Patent: US 7,311,968 B2
• Time in Patent Office: Days
• US Class Current: 428/195.100
• CPC Class Codes: A61F 13/53 characterised by the absorbing medium A61F13/20 takes precedence
• CPC Class Codes: A61F 13/539 characterised by the connection of the absorbent layers with each other or with the outer layers
• CPC Class Codes: A61F 2013/53051 being only in particular parts or specially arranged
• CPC Class Codes: A61F 2013/530554 and being fixed to a web
• CPC Class Codes: A61L 15/60 Liquid-swellable gel-forming materials, e.g. super-absorbents
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 428/254 Polymeric or resinous material
• CPC Class Codes: Y10T 428/2913 Rod, strand, filament or fiber
• CPC Class Codes: Y10T 428/2927 including structurally defined particulate matter
• CPC Class Codes: Y10T 442/699 Including particulate material other than strand or fiber material

Abstract

This invention is directed to super-absorbent material, which comprises a super absorbent polymer core that is coated with an organic, polar coating agent, and whereby the particulate super-absorbent material has a contact angle and a corresponding cos CA_m (as defined herein), whereby the cos CA_m is more than 0.3, and whereby, when said coating agent is in the form of particles, said coating agent particles have a (weight) mean particle size of from 0.001 to 1 micron. The material is useful for absorbent structures and absorbent articles (comprising such structures). The coated super-absorbent material is typically present in said absorbent structure at least at a concentration of 50% by weight of the structure, preferably even 80% or even 90%. The invention also provides a process for making the absorbent material.

Claims

1. An absorbent article comprising an absorbent structure, said absorbent structure comprising a particulate super-absorbent material comprising a particulate core of super-absorbent polymers, said particulate core coated with a coating agent comprising an organic coating compound which has one or more polar groups, and wherein the particulate super-absorbent material has a contact angle and a corresponding cos CA_m, wherein the cos CA_m is greater than 0.3.

2. The absorbent article of claim 1 wherein said absorbent structure further comprises cellulose fibers.

3. The absorbent article of claim 1 wherein said absorbent article is selected from the group consisting of a sanitary napkin, a panty liner, a diaper, a training pant, and an adult incontinence article.

4. The absorbent article as in claim 1 wherein said absorbent structure comprises at least a first area and a second areas each areas comprising said super-absorbent material, wherein said super-absorbent material within the first area is different from the super-absorbent material in the second area by at least the level of coating agent present therein.

5. A process for making an absorbent article comprising an absorbent structure with two or more areas, said process comprising the steps of:

a. providing an absorbent structure;

b. adding a plurality of super-absorbent polymer cores to said structure;

c. adding a first amount of a coating agent to a first part of the structure; and

d. adding a second amount of the coating agent to a second part of the structure, wherein said second amount of coating agent is greater than said first amount of coating agent.