Nonwoven articles

• US 6,013,587 A
• Filed: 05/29/1996
• Issued: 01/11/2000
• Est. Priority Date: 06/02/1993
• Status: Expired due to Fees

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Truong, Jack G., Rock, Michael M. Jr., Studiner, Willa M., Wright, Bradford B.
• Primary Examiner(s): Choi, Kathleen
• Application Number:
  US08/655,048
• Time in Patent Office: 1,322 Days
• Field of Search: 442/59, 442/104, 442/102, 442/166
• US Class Current: 442/166
• CPC Class Codes: D04H 1/587 characterised by the bonding agents used
• CPC Class Codes: D04H 1/64 the bonding agent being applied in wet state, e.g. chemical agents in dispersions or solutions
• CPC Class Codes: Y10T 442/20 Coated or impregnated woven, knit, or nonwoven fabric which is not [a] associated with another preformed layer or fiber layer or, [b] with respect to woven and knit, characterized, respectively, by a particular or differential weave or knit, wherein the coating or impregnation is neither a foamed material nor a free metal or alloy layer
• CPC Class Codes: Y10T 442/2352 Coating or impregnation functions to soften the feel of or improve the "hand" of the fabric
• CPC Class Codes: Y10T 442/2369 Coating or impregnation improves elasticity, bendability, resiliency, flexibility, or shape retention of the fabric
• CPC Class Codes: Y10T 442/2861 Coated or impregnated synthetic organic fiber fabric
• CPC Class Codes: Y10T 442/2877 Coated or impregnated polyvinyl alcohol fiber fabric
• CPC Class Codes: Y10T 442/60 Nonwoven fabric [i.e., nonwoven strand or fiber material]
• CPC Class Codes: Y10T 442/676 Vinyl polymer or copolymer sheet or film [e.g., polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, etc.]

Abstract

Nonwoven articles having high durability and absorbent characteristics, and their methods of manufacture, are presented. One preferred article is characterized by

(a) a nonwoven web comprised of organic fibers comprised of polymers having a plurality of pendant hydroxyl groups; and

(b) a binder comprising an at least partially crosslinked and at least partially hydrolyzed polymeric resin having a plurality of pendant resin hydroxyl groups, the resin crosslinked by a crosslinking agent, the crosslinking agent selected from the group consisting of organic titanates and amorphous metal oxides, the polymeric resin derived from monomers selected from the group consisting of monomers within the general formula ##STR1## wherein: X is selected from the group consisting of Si(OR⁴ OR⁵ OR⁶) and O(CO)R⁷ ; and

R¹ -R⁷ inclusive are independently selected from the group consisting of hydrogen and organic radicals having from 1 to about 10 carbon atoms, inclusive, and combinations thereof.

Claims

1. An absorbent nonwoven article comprising:

(a) a nonwoven web comprised of polyvinyl alcohol fibers; and

(b) a binder coated on at least a portion of said fibers, said binder comprising syndiotactic polyvinyl alcohol having a plurality of hydroxyl groups, said syndiotactic polyvinyl alcohol having a triad syndiotacticity of said hydroxyl groups of at least 30%.

2. An absorbent article in accordance with claim 1 wherein said binder comprises unhydrolyzed polymers derived from monomers selected from the group consisting of monomers within the general formula ##STR5## wherein:

X is selected from the group consisting of Si(OR⁴ OR⁵ OR⁶) and OCOR⁷ ; and

R¹ -R⁷ inclusive are independently selected from the group consisting of hydrogen and organic radicals having from 1 to about 10 carbon atoms, inclusive, and combinations thereof.

3. An absorbent article in accordance with claim 1 wherein said syndiotactic polyvinyl alcohol is bonded to at least a portion of said polyvinyl alcohol fibers through bonds between said pendant hydroxyl groups on said fibers, a bonding agent, and said pendant hydroxyl groups on said syndiotactic polyvinyl alcohol.

4. An absorbent article in accordance with claim 1 wherein said syndiotactic polyvinyl alcohol is at least partially crosslinked by a crosslinking agent.

5. An absorbent article in accordance with claim 3 wherein said syndiotactic polyvinyl alcohol is at least partially crosslinked by a crosslinking agent.

6. An absorbent article in accordance with claim 5 wherein said crosslinking agent and said bonding agent are the same.

7. An absorbent article in accordance with claim 1 wherein said web further comprises fibers selected from the group of cotton, viscose rayon, cuprammonium rayon, polyesters, polypropylene, and combinations thereof.

8. An absorbent article in accordance with claim 1 wherein the polyvinyl alcohol has a syndiotacticity within the range from about 45% to about 100%.

9. An absorbent article in accordance with claim 3 wherein the bonding agent is selected from the group consisting of organic titanates and dialdehydes.

10. An absorbent article in accordance with claim 4 wherein the crosslinking agent is selected from the group consisting of organic titanates and dialdehydes.

11. An absorbent article in accordance with claim 5 wherein the crosslinking agent is selected from the group consisting of organic titanates and dialdehydes.

12. An absorbent article in accordance with claim 7 wherein the nonwoven web further comprises rayon fibers and has a ratio of polyvinyl alcohol fibers to rayon fibers within a weight range of about 30:

70 to about 70;

30.

16. An absorbent article in accordance with claim 1 wherein the syndiotactic polyvinyl alcohol is hydrolyzed poly(vinyl trifluoroacetate-co-(3-allyl-2,2'"'"'-dihydroxy-4,4'"'"'-dimethoxybenzophenone)).

13. An absorbent nonwoven article comprising:

(a) a nonwoven web comprised of organic fibers, said organic fibers comprised of polymers having a plurality of pendant hydroxyl groups; and

(b) a binder coated on at least a portion of said fibers, said binder consisting essentially of syndiotactic polyvinyl alcohol having a plurality of hydroxyl groups, said syndiotactic polyvinyl alcohol having a triad syndiotacticity of said hydroxyl groups of at least 30%.

14. An absorbent nonwoven article comprising:

(a) a nonwoven web comprised of organic fibers, said organic fibers comprised of polymers having a plurality of pendant hydroxyl groups; and

(b) a binder coated on at least a portion of said fibers, said binder comprising syndiotactic polyvinyl alcohol having a plurality of hydroxyl groups, said syndiotactic polyvinyl alcohol having a triad syndiotacticity of said hydroxyl groups of at least 30%, wherein said binder is essentially free of a chemical crosslinking agent.

15. An absorbent nonwoven article comprising:

(a) a nonwoven web comprised of organic fibers, said organic fibers comprised of a combination of rayon fibers and polyvinyl alcohol fibers; and

(b) a binder coated on at least a portion of said fibers, said binder consisting essentially of syndiotactic polyvinyl alcohol having a plurality of hydroxyl groups, said syndiotactic polyvinyl alcohol having a triad syndiotacticity of said hydroxyl groups of at least 30%.