EP0450924A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for treating the surface of an absorbent resin
Assignee: Nippon Shokubai Co Ltd
•
Filing: 1991-04-02
•
Granted: —
•
Expires: 2011-04-02
Abstract
Abstract A method for treating the surface of an absorbent resin which comprises mixing (I) 100 parts by weight of an absorbent resin powder having a carboxyl group, (II) 0.01 to 30 parts by weight of a polyhydric alcohol, (III) 0 to 50 parts by weight of water and (IV) 0 to 60 parts by weight of a hydrophilic organic solvent, and heat-treating at a temperature in the range of 90 to 250°C to treat the surface of said absorbent resin powder (I) until the reaction of said absorbent resin powder (I) with said polyhydric alcohol (II) is completed, wherein the time for completion of the reaction is the time that satisfies the following equation (a-1): 30 ≦ 100 + C) B/A ≦ 80 wherein A is absorption capacity of said absorbent resin powder (I) for physiological saline solution, B is the absorption capacity of the resultant treated absorbent resin for physiological saline solution, and C is parts by weight of said polyhydric alcohol (II) used per 100 parts by weight of said absorbent resin powder (I).
Inventors
- 👤 Kazumasa Kimura
- 👤 Takumi Hatsuda
- 👤 Kinya Nagasuna
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 04:00
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; C08F; C08F8/00; C08F8/14; C08J3/24; C08L; C08L101/00; C08F2810/00; C08F2810/20; C08J2300/00; C08J2300/14
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
180 words
A method for treating the surface of an absorbent resin which comprises mixing (I) 100 parts by weight of an absorbent resin powder having a carboxyl group, ( II ) 0. 01 to 30 parts by weight of a polyhydric alcohol, (III) 0 to 50 parts by weight of water and (IV) 0 to 60 parts by weight of a hydrophilic organic solvent, and heat-treating at a temperature in the range of 90 to 250°C to treat the surface of said absorbent resin powder (I) until the reaction of said absorbent resin powder (I) with said polyhydric alcohol (II) is completed, wherein the time for completion of the reaction is the time that satisfies the following equation (a-1 ): 30 ≦ (100 + C) B/A ≦ 80 wherein A is absorption capacity of said absorbent resin powder (I) for physiological saline solution, B is the absorption capacity of the resultant treated absorbent resin for physiological saline solution, and C is parts by weight of said polyhydric alcohol (II) used per 100 parts by weight of said absorbent resin powder (I).
Claim 2
Dependent Claim
32 words
A method according to Claim 1, wherein the amount of said polyhydric alcohol (II) is 0.1 to 10 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 3
Dependent Claim
30 words
A method according to Claim 1, wherein the amount of water (III) is 0.1 to 20 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 4
Dependent Claim
33 words
A method according to Claim 1, wherein the amount of said hydrophilic organic solvent (IV) is 0.1 to 20 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 5
Dependent Claim
48 words
A method according to Claim 1, wherein the amount of water (III ) is 0.1 to 20 parts by weight and the amount of said hydrophilic organic solvent (IV ) is 0.1 to 20 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 6
Dependent Claim
31 words
A method according to Claim 1, wherein the time for completion of the reaction is the time that satisfies the following equation (a-2): 40 ≦ (100 + C) B/A ≦ 70
Claim 7
Dependent Claim
19 words
Substantially water-insoluble, absorbent, hydrogel-forming, polymer composition produced according to the method of Claims 1, 2, 3, 5 or 6.
Claim 8
Dependent Claim
149 words
A method according to Claim 1, wherein heat-treating is carried out in the presence of 0.01 to 10 parts by weight of a water-insoluble fine powder (V) until the reaction of said absorbent resin powder (I) with said polyhydric alcohol (II) is completed, wherein the time for completion of the reaction is the time that satisfies the following Equation (b-1): 30 ≦ (100 + C + D) B/A ≦ 80 wherein A is the absorption capacity of said absorbent resin powder (I) for a physiological saline solution, B is the absorption capacity of the resultant treated absorbent resin for physiological saline solution, and C is parts by weight of said polyhydric alcohol (II) used per 100 parts by weight of said absorbent resin powder (I), and D is parts by weight of said water-insoluble fine powder (V) used per 100 parts by weight of the absorbent resin powder (I).
Claim 9
Dependent Claim
33 words
A method according to Claim 8, wherein the amount of said water-insoluble fine powder (V) is 0.01 to 5 parts byweight per 100 parts by weight of the absorbent resin powder (I) .
Claim 10
Dependent Claim
22 words
A method according to Claim 8, wherein the particle size of said water-insoluble fine powder (V) is less than about 50 µm.
Claim 11
Dependent Claim
18 words
A method according to Claim 8, wherein said water-insoluble fine powder (V) is a water-insoluble inorganic fine powder.
Claim 12
Dependent Claim
33 words
A method according to Claim 11, wherein said water-insoluble inorganic fine powder is at least one member selected from the group consisting of silicon dioxide, titanium dioxide, aluminum oxide, zeolite, kaolin, and hydrotalcite.
Claim 13
Dependent Claim
19 words
A method according to Claim 8, wherein said water-insoluble fine powder (V) is mixed before heat-treating is carried out.
Claim 14
Dependent Claim
20 words
A method according to Claim 13, wherein said mixing is carried out in the presence of water-insoluble fine powder (V).
Claim 15
Dependent Claim
33 words
A method according to Claim 8, wherein the amount of said polyhydric alcohol (II) is 0. 1 to 10 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 16
Dependent Claim
30 words
A method according to Claim 8, wherein the amount of water (III) is 0.1 to 20 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 17
Dependent Claim
33 words
A method according to Claim 8, wherein the amount of said hydrophilic organic solvent (IV) is 0.1 to 20 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 18
Dependent Claim
46 words
A method according to Claim 8, wherein the amount of water (III) is 0.1 to 20 parts by weight and the amount of said hydrophilic organic solvent (IV) is 0.1 to 20 parts by weight per 100 parts by weight of said absorbent resin powder (I).
Claim 19
Dependent Claim
35 words
A method according to Claim 8, wherein the time for completion of the reaction is the time that satisfies the following equation ( b-2 ): 40 ≦ (100 + C + D) B/A ≦ 70
Claim 20
Dependent Claim
20 words
Substantially water-insoluble, absorbent, hydrogel-forming, polymer composition produced according to the method of Claims 8, 11, 15, 16, 18 or 19.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.