Water-absorbing polymer particles delaying the decomposition of body fluids, composites comprising these and use thereof

1. A water-absorbing, antimicrobial polymer particle comprising:

from about 1 to about 500 ppm, based on the polymer particle, of a silver ion based on a silver salt Ag m X n , wherein the silver salt has a solubility product of at least about 1×10 −8 (mol/l) m+n ;

at least about 10 wt. %, based on the polymer particle, of a water-absorbing polymer based on:

(α1) from about 50 to about 99.99 wt. % of acrylic acid which is neutralized to at least 25 mol. %,

(α2) from 0 to about 40 wt. % polymerized, monoethylenically unsaturated monomers polymerizable with α1,

(α3) from about 0.01 to about 5 wt. % of one or more crosslinkers,

(α4) from 0 to about 30 wt. % of a water soluble polymer as well as

(α5) from 0 to about 20 wt. % of one or more auxiliaries,

wherein the sum of the weight quantities (α1) to (α5) amounts to 100 wt. %;

wherein the concentration of the silver ion based on a silver salt in at most about 90 vol. % of the water-absorbing, antimicrobial polymer particle is less than about 0.01 ppm and

wherein the water-absorbing, antimicrobial polymer particle is post-crosslinked with a post-crosslinker in a quantity within a range of from about 0.01 to about 30 wt. %, based on the weight of the polymer particle.

2. The water-absorbing, antimicrobial polymer particle comprising:

from about 1 to about 500 ppm, based on the polymer particle, of a silver ion based on a silver salt Ag m X n , wherein the silver salt has a solubility product of at least about 1×10 −8 (mol/l) m+n ;

at least about 10 wt. %, based on the polymer particle, of a water-absorbing polymer based on:

(α1) from about 50 to 99.99 wt. % of acrylic acid which is neutralized to at least 25 mol. %,

(α2) from 0 to about 40 wt. % polymerized, monoethylenically unsaturated monomers polymerizable with α1,

(α3) from about 0.01 to about 5 wt. % of one or more crosslinkers,

(α4) from 0 to about 30 wt. % of a water soluble polymer as well as

(α5) from 0 to about 20 wt. % of one or more auxiliaries,

wherein the sum of the weight quantities (α1) to (α5) amounts to 100 wt. %;

wherein the concentration of the silver ion based on a silver salt in no volume part of the water-absorbing, antimicrobial polymer particle is less than about 0.01 ppm and

wherein the water-absorbing, antimicrobial polymer particle is post-crosslinked with a post-crosslinker in a quantity within a range of from about 0.01 to about 30 wt. %, based on the weight of the polymer particle.

3. The water-absorbing, antimicrobial polymer particle comprising:

from about 1 to about 500 ppm, based on the polymer particle, of a silver ion based on a silver salt Ag m X n , wherein the silver salt has a solubility product of at least about 1×10 −8 (mol/l) m+n ; at least about 10 wt. %, based on the polymer particle, of a water-absorbing polymer based on:

(α1) from about 50 to about 99.99 wt. % of acrylic acid which is neutralized to at least 25 mol. %,

(α2) from 0 to about 40 wt. % polymerized, monoethylenically unsaturated monomers polymerizable with α1,

(α3) from about 0.01 to about 5 wt. % of one or more crosslinkers,

(α4) from 0 to about 30 wt. % of a water soluble polymer as well as

(α5) from 0 to about 20 wt. % of one or more auxiliaries,

wherein the sum of the weight quantities (α1) to (α5) amounts to 100 wt. %;

wherein the concentration of the silver ion based on a silver salt in at most about 90 % of the water-absorbing, antimicrobial polymer particle is less than about 0.01 ppm and

wherein the pH value of the water-absorbing, antimicrobial polymer particle lies within a range from about 4.5 to about 7.

4. The water-absorbing, antimicrobial polymer particle comprising:

from about 1 to about 500 ppm, based on the polymer particle, of a silver ion based on a silver salt Ag m X n wherein the silver salt has a solubility product of at least about 1×10 −8 (mol/l) m+n ;

at least about 10 wt. %, based on the polymer particle, of a water-absorbing polymer based on:

(α1) from about 50 to about 99.99 wt. % of acrylic acid which is neutralized to at least 25 mol. %,

(α2) from 0 to about 40 wt. % polymerized, monoethylenically unsaturated monomers polymerizable with α1,

(α3) from about 0.01 to about 5 wt. % of one or more crosslinkers,

(α4) from 0 to about 30 wt. % of a water soluble polymer as well as

(α5) from 0 to about 20 wt. % of one or more auxiliaries,

wherein the sum of the weight quantities (α1) to (α5) amounts to 100 wt. %;

wherein the concentration of the silver ion based on a silver salt in no volume part of the water-absorbing, antimicrobial polymer particle is less than about 0.01 ppm and

wherein the pH value of the water-absorbing, antimicrobial polymer particle lies within a range of from about 4.5 to about 7.

5. A process for producing a water-absorbing, antimicrobial polymer particle, whereby as reagents

(β1) from 55 to about 99.99 wt. % of acrylic acid which is neutralized to at least 25 mol. %,

(β2) from 0 to about 40 wt. % of polymerized, monoethylenically unsaturated monomers polymerizable with β1,

(β3) from about 0.01 to about 5 wt. % of one or more crosslinkers,

(β4) from 0 to about 30 wt. % of a water soluble polymer as well as

(β5) from 0 to about 20 wt. % of one or more auxiliaries, wherein the sum of the weight quantities (β1) to (β5) amounts to 100 wt. % are polymerized together with formation of a water-absorbing polymer;

wherein from about 1 to about 500 ppm of a silver ion in the form of a water soluble silver salt Ag m X n with a solubility product of at least about 1×10 −8 (mol/l) m+n dissolved in a solvent, based on the reagents, is added to the reagents before the end of the formation of the water-absorbing polymer, and

wherein the water-absorbing polymer is comminuted, dried and optionally ground and is post-crosslinked in a post-crosslinking step with a post-crosslinker in a quantity within a range of from about 0.01 to about 30 wt. %, based on the as yet untreated polymer.

6. The process for producing a water-absorbing, antimicrobial polymer particle, whereby as reagents

(β1) from 50 to about 99.99 wt. % of acrylic acid which is neutralized to at least 25 mol. %,

(β2) from 0 to about 40 wt. % of polymerized, monoethylenically unsaturated monomers polymerizable with β1,

(β3) from about 0.01 to about 5 wt. % of one or more crosslinkers,

(β4) from 0 to about 30 wt. % of a water soluble polymer as well as

(β5) from 0 to about 20 wt. % of one or more auxiliaries, wherein the sum of the weight quantities (β1) to (β5) amounts to 100 wt. %, are polymerized together with formation of a water-absorbing polymer;

wherein from about 1 to about 500 ppm of a silver ion in the form of a water soluble silver salt Ag m X n with a solubility product of at least about 1×10 −8 (mol/l) m+n dissolved in a solvent, based on the reagents, is added to the reagents before the end of the formation of the water-absorbing polymer, and

wherein the ethylenically unsaturated, acid groups-containing monomers (β1) are neutralized such that the pH value of the water-absorbing polymer particle lies within the range of from about 4.5 to about 7.

7. The process for producing a water-absorbing, antimicrobial polymer particle, whereby as reagents

(β1) from 55 to about 99.99 wt. % of acrylic acid which is neutralized to at least 25 mol. %,

(β2) from 0 to about 40 wt. % of polymerized, monoethylenically unsaturated monomers polymerizable with β1,

(β3) from about 0.01 to about 5 wt. % of one or more crosslinkers,

(β4) from 0 to about 30 wt. % of a water soluble polymer as well as

(β5) from 0 to about 20 wt. % of one or more auxiliaries,

wherein the sum of the weight quantities (β1) to (β5) amounts to 100 wt. % are polymerized together with formation of a water-absorbing polymer;

wherein from about 1 to about 500 ppm of a silver ion in the form of a water soluble silver salt Ag m X n with a solubility product of at least about 1×10 −8 (mol/l) m+n dissolved in a solvent, based on the reagents, is added to the reagents before the end of the formation of the water-absorbing polymer, and

wherein the water-absorbing polymer is comminuted, dried and optionally ground and is post-crosslinked in a post-crosslinking step with a post-crosslinker in a quantity within a range of from about 0.01 to about 30 wt. %, based on the as yet untreated polymer.

8. The water-absorbing anti-microbial polymer particle of claim 1 wherein from about 50 to about 80 mol % of the acid groups of the acrylic acid are neutralized with an alkali or alkaline earth salt.

9. The water-absorbing anti-microbial polymer particle of claim 1 wherein the silver salt is silver nitrate.

10. The water-absorbing anti-microbial polymer particle of claim 1 further comprising at least one of the following properties:

(A) the maximum absorption of about 0.9 wt. % NaCl solution according to ERT 440.1-99 lies within a range of from at least about 10 to about 1000 g/g;

(B) the part extractable with about 0.9 wt. % aqueous NaCl solution according to ERT 470.1-99 amounts to less than about 30 wt. %, respectively based on the polymer;

(C) the bulk density according to ERT 460.1-99 lies within the range of from about 300 to about 1000 g/l;

(D) the pH value of about 1 g of the polymer in about 11 water according to ERT 400.1-99 lies within the range of from about 4 to about 10;

(E) the Centrifugation Retention Capacity (CRC) according to ERT 441.1-99 lies within the range of from about 10 to about 100 g/g.

11. Fibers, films, foams or formed bodies, comprising the polymer particle of claim 1 .

12. A composite comprising the polymer particle according to claim 1 and a substrate.

13. A hygiene article, for prevention or treatment of skin irritations caused by body excretions comprising the polymer particle according to claim 1 .