Patent EP0200973A2 successfully refreshed from Google Patents.
EP0200973A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Fine cellulose particles.
Assignee: Kanebo Ltd
•
Filing: 1986-04-18
•
Granted: —
•
Expires: 2006-04-18
Abstract
Abstract @ A process for producing fine cellulose particles, which comprises (1) mixing viscose with a water-soluble anionic polymeric compound or polyethylene glycol or its derivative to form a dispersion of fine particles of viscose, (2) (i) heating the dispersion or mixing it with a coagulating agent to thereby coagulate the viscose in the dispersion, and thereafter neutralizing it with an acid to form fine particles of cellulose, or (ii) coagulating and neutralizing the dispersion with an acid to form fine particles of cellulose, and (3) thereafter, separating the fine particles of cellulose from the mother liquor. The fine cellulose particles (a) are composed substantially of II-type cellulose, (b) have a crystallinity, of 5 to 35 % by weight, (c) are composed substantially of particles of not more than 20 micrometers, and (d) have a sharp particle size distribution.
Inventors
- 👤 Shigeru Okuma
- 👤 Kanji Yamagishi
- 👤 Masami Hara
- 👤 Keizo Suzuki
- 👤 Toshihiro Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 03:51
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08J3/16; C08B; C08B16/00; C08L; C08L1/00; C08L1/02; C08L1/06; C08J2301/00; C08J2301/06
Claims Analysis
Total Claims: 55
Claim 1
Independent Claim
109 words
A process for producing fine cellulose particles, which comprises (1) mixing viscose with at least a water-soluble anionic polymeric compound to form a dispersion of fine particles of viscose, (2) (i) heating the dispersion or mixing it with a coagulating agent to thereby coagulate the viscose in the dispersion, and thereafter neutralizing it with an acid to form fine particles of cellulose, or (ii) coagulating and neutralizing the dispersion with an acid to form fine particles of cellulose, and (3) thereafter, separating the fine particles of cellulose from the mother liquor, and as required, subjecting them to removal of sulfur, washing with an acid, washing with water, or drying.
Claim 2
Dependent Claim
109 words
A process for producing fine cellulose particles, which comprises (1) mixing viscose with at least a water-soluble anionic polymeric compound to form a dispersion of fine particles of viscose, (2) (i) heating the dispersion or mixing it with a coagulating agent to thereby coagulate the viscose in the dispersion, and thereafter neutralizing it with an acid to form fine particles of cellulose, or (ii) coagulating and neutralizing the dispersion with an acid to form fine particles of cellulose, and (3) thereafter, separating the fine particles of cellulose from the mother liquor, and as required, subjecting them to removal of sulfur, washing with an acid, washing with water, or drying.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein the viscose has a cellulose concentration of 3 to 15 % by weight.
Claim 4
Dependent Claim
22 words
The process of claim 1 wherein the viscose has an alkali concentration, as sodium hydroxide, of 2 to 15 % by weight.
Claim 5
Dependent Claim
27 words
The process of claim 1 wherein the proportion of alkali as sodium hydroxide is 40 to 100 % by weight based on the cellulose of the viscose.
Claim 6
Dependent Claim
16 words
The process of claim 1 wherein the viscose has a gamma value of 30 to 100.
Claim 7
Dependent Claim
18 words
The process of claim 1 wherein the viscose has a viscosity at 20°C of 50 to 20,000 centipoises.
Claim 8
Dependent Claim
16 words
The process of claim 1 wherein the viscose has a salt point of 3 to 20.
Claim 9
Dependent Claim
38 words
The process of claim 1 wherein the water-soluble anionic polymeric compound has a sulfonic acid group, a phosphonic acid group or a carboxylic acid group in the form of a free acid or salt as an anionic group.
Claim 10
Dependent Claim
41 words
The process of claim 1 wherein the water-soluble anionic polymeric compound has units derived from at least one monomer selected from the group consisting of vinylsulfonic acid, styrenesulfonic acid, methylstyrenesulfonic acid, allylsulfonic acid, methallylsulfonic acid, acrylamidomethylpropanesulfonic acid, and salts of these.
Claim 11
Dependent Claim
39 words
The process of claim 1 wherein the water-soluble anionic polymeric compound has units derived from at least one monomer selected from the group consisting of acrylic acid, methacrylic acid, styrenecarboxylic acid, maleic acid, itaconic acid and salts of these.
Claim 12
Dependent Claim
32 words
The process of claim 1 wherein the water-soluble anionic polymeric compound has units derived from at least one monomer selected from the group consisting of styrenephosphonic acid, vinylphosphonic acid and salts threof.
Claim 13
Dependent Claim
33 words
The process of claim 1 wherein the water-soluble anionic polymeric compound is a homopolymer or copolymer containing at least 20 mole % of the monomeric units according to claim 9, 10 or 11.
Claim 14
Dependent Claim
21 words
The process of claim 1 wherein the water-soluble anionic polymeric compound has a number average molecular weight of at least 5,000.
Claim 15
Dependent Claim
21 words
The process of claim 1 wherein the water-soluble anionic polymeric compound is used as a 0.5-25 % by weight aqueous solution.
Claim 16
Dependent Claim
27 words
The process of claim 1 wherein the water-soluble anionic polymeric compound is used as an aqueous solution having a viscosity at 20°C of 30,000 to 50,000 centipoises.
Claim 17
Dependent Claim
27 words
The process of claim 1 wherein the viscose and the water-soluble anionic polymeric compound are mixed at a temperature lower than the boiling point of carbon disulfide.
Claim 18
Dependent Claim
19 words
The process of claim 1 wherein the viscose and the water-soluble anionic polymeric compound are mixed by mechanical stirring.
Claim 19
Dependent Claim
40 words
The process of claim 1 wherein the viscose and the water-soluble anionic polymeric compound are mixed in such proportions that 0.3 to 100 parts by weight of the water-soluble anionic polymeric compound is used per part by weight of cellulose.
Claim 20
Dependent Claim
31 words
The process of claim 1 wherein the dispersion of fine particles in step (1) is formed by mixing the viscose with the water-soluble anionic polymeric compound and a cationic polymeric compound.
Claim 21
Dependent Claim
12 words
The process of claim 19 wherein the cationic polymeric compound is water-soluble.
Claim 22
Dependent Claim
20 words
The process of claim 19 wherein the cationic polymeric compound is a polymeric compound of the quaternary ammonium salt type.
Claim 23
Dependent Claim
66 words
The process of claim 19 wherein the cationic polymeric compound is an ammonium salt represented by the following formula (I) wherein R' and R 2 are identical or different and each represents a hydrogen atom, a lower alkyl group having 1 to 5 carbon atoms or a benzyl group, X' represents one equivalent of an anion, and n is a number showing the degree of polymerization.
Claim 24
Dependent Claim
81 words
The process of claim 19 wherein the cationic polymeric compound is an ammonium salt represented by the following formula (11) wherein R 3 represents a hydrogen atom or a methyl group, R 4 , R S and R 6 are identical or different and each represents a hydrogen atom, a lower alkyl group having 1 to 5 carbon atoms, or a benzyl group, X Z represents one equivalent of an anion, and m is a number showing the degree of polymerization.
Claim 25
Dependent Claim
70 words
The process of claim 19 wherein the cationic polymeric compound is an ammonium salt represented by the following formula (III) wherein R 7 , R" and R 9 are identical or different and each represents a hydrogen atom, a lower alkyl group having 1 to 5 carbon atoms or a benzyl group, X I represents one equivalent of an anion, and ℓ is a number showing the degree of polymerization.
Claim 26
Dependent Claim
20 words
The process of claim 19 wherein the cationic polymeric compound has a number average molecular weight of 1,000 to 100,000.
Claim 27
Dependent Claim
32 words
The process of claim 19 wherein the cationic polymeric compound is used in an amount of 0.0005 to 0.4 part by weight per part by weight of the water-soluble anionic polymeric compound.
Claim 28
Dependent Claim
22 words
The process of claim 1 wherein the coagulation reaction in step (2) is carried out while the resulting dispersion is being mixed.
Claim 29
Dependent Claim
27 words
The process of claim 1 wherein the coagulation by heating the step (2), (i) is carried out at a temperature above the boiling point of carbon disulfide.
Claim 30
Dependent Claim
26 words
The process of claim 1 wherein the coagualtion with the coagulating agent in step (2), (i) is carried out at a temperature of 0 to 40°C.
Claim 31
Dependent Claim
56 words
The process of claim 1 wherein the coagulating agent used in step (2), (i) is a lower aliphatic alcohol, an alkali metal salt of an inorganic acid, an alkaline earth metal salt of an inorganic acid, an inorganic acid, an organic acid, or a mixture of these with each other or with a water-soluble polymeric compound.
Claim 32
Dependent Claim
20 words
The process of claim 1 wherein the acid used for neutralization in step (2), (i) is an inorganic strong acid.
Claim 33
Dependent Claim
24 words
The process of claim 1 wherein the coagulation and neutralization in step (2), (ii) are carried out at a temperature of 0 to 40°C.
Claim 34
Dependent Claim
22 words
The process of claim 1 wherein the acid used for coagulation and neutralization in step (2), (ii) is an inorganic strong acid.
Claim 35
Dependent Claim
143 words
A process for producing fine cellulose particles, which comprises (1) mixing viscose with a water-soluble polyethylee glycol or its derivative having a number average molecular weight of at least 1,500 at a temperature of at least 55°C to form a dispersion of fine particles of viscose, (2) (i) heating the dispersion at a temperature equal to, or higher than, the temperature used in forming the dispersion, or mixing the dispersion with a coagulating agent to thereby coagulate the viscose in the dispersion, and thereafter neutralizing it with an acid to form fine particles of cellulose, or (ii) coagulating and neutralizing the above dispersion with an acid to form fine particles of cellulose, and (3) thereafter, separating the fine particles of cellulose from the mother liquor, and as required, subjecting them to removal of sulfur, washing with an acid, washing with water, or drying.
Claim 36
Dependent Claim
143 words
A process for producing fine cellulose particles, which comprises (1) mixing viscose with a water-soluble polyethylee glycol or its derivative having a number average molecular weight of at least 1,500 at a temperature of at least 55°C to form a dispersion of fine particles of viscose, (2) (i) heating the dispersion at a temperature equal to, or higher than, the temperature used in forming the dispersion, or mixing the dispersion with a coagulating agent to thereby coagulate the viscose in the dispersion, and thereafter neutralizing it with an acid to form fine particles of cellulose, or (ii) coagulating and neutralizing the above dispersion with an acid to form fine particles of cellulose, and (3) thereafter, separating the fine particles of cellulose from the mother liquor, and as required, subjecting them to removal of sulfur, washing with an acid, washing with water, or drying.
Claim 37
Dependent Claim
22 words
The process of claim 34 wherein the polyethylene glycol or its derivative has a number average molecular weight of 1,500 to 400,000.
Claim 38
Dependent Claim
88 words
The process of claim 34 wherein the polyethylene glycol derivative is a water-soluble compound obtained by blocking only the hydroxyl group of one end of polyethylene glycol with an alkyl group having 1 to 18 carbon atoms, a phenyl group substituted by an alkyl group having 1 to 18 carbon atoms, or an acyl group having 2 to 18 carbon atoms, or an A-B-A'-type block copolymer (wherein A and A' are identical or different and each represents a polyethylene oxide block, and B represents a polypropylene oxide block).
Claim 39
Dependent Claim
23 words
The process of claim 34 wherein the water-soluble polyethylene glycol or its derivative is used as a 0.5-60 % by weight aqueous solution.
Claim 40
Dependent Claim
38 words
The process of claim 34 wherein the viscose and polyethylene glycol or its derivative are mixed in such proportions that 1 to 30 parts of polyethylene glycol or its derivative is used per part by weight of cellulose.
Claim 41
Dependent Claim
30 words
The process of claim 34 wherein the coagulation by heating and by using a coagulating agent in step (2), (i) is carried out at a temperature of 60 to 90°C.
Claim 42
Dependent Claim
24 words
The process of claim 34 wherein the coagulation and neutralization in step (2), (ii) are carried out at a temperature of 60 to 90°C.
Claim 43
Dependent Claim
89 words
A fine cellulose particles characterized by (a) being composed substantially of ll-type cellulose, (b) having a crystallinity, determined by X-ray diffractometry, of 5 to 35 % by weight, (c) being composed substantially of spherical or elongated spherical particles having an average particle diameter of not more than 20 micrometers, and (d) having such a particle size distribution that the proportion of particles having a particle diameter in the range of the average particle diameter (micrometers) t 5 micrometrs is at least 70 % by weight of the entire particles.
Claim 44
Dependent Claim
89 words
A fine cellulose particles characterized by (a) being composed substantially of ll-type cellulose, (b) having a crystallinity, determined by X-ray diffractometry, of 5 to 35 % by weight, (c) being composed substantially of spherical or elongated spherical particles having an average particle diameter of not more than 20 micrometers, and (d) having such a particle size distribution that the proportion of particles having a particle diameter in the range of the average particle diameter (micrometers) t 5 micrometrs is at least 70 % by weight of the entire particles.
Claim 45
Dependent Claim
16 words
The fine cellulose particles of claim 41 which have a crystallinity of 5 to 30 %.
Claim 46
Dependent Claim
16 words
The fine cellulose particles of claim 41 which have a crystallinity of 10 to 28 %.
Claim 47
Dependent Claim
27 words
The fine cellulose particles of claim 41 which are composed substantially of spherical or elongated spherical particles having an average particle diameter of 1 to 18 micrometers.
Claim 48
Dependent Claim
47 words
The fine cellulose particles of claim 41 which have such a particle size distribution that the proportion of particles having a particle diameter in the range of the average particle diameter - (micrometrs) ± 5 micrometers is at least 75 % by weight of the entire particles.
Claim 49
Dependent Claim
16 words
The fine cellulose particles wherein the cellulose has a degree of polymerization of 100 to 700.
Claim 50
Dependent Claim
16 words
The fine cellulose particles wherein the cellulose has a degree of polymerization of 100 to 700.
Claim 51
Dependent Claim
19 words
The fine cellulose particles of claim 41 which have a degree of water swelling of 100 to 500 %.
Claim 52
Dependent Claim
14 words
The fine cellulose particles which have a copper value of not more than 3.
Claim 53
Dependent Claim
14 words
The fine cellulose particles which have a copper value of not more than 3.
Claim 54
Dependent Claim
34 words
The fine cellulose particles of claim 41 wherein the volume of pores having a pore diameter, measured by the mercury porosimeter method, of 0.01 to 0.5 micrometers, is not more than 60 x 10-s.
Claim 55
Dependent Claim
33 words
Fine cellulose particles comprising a mixture of at least two groups of the fine cellulose particles of claim 41, said groups differing from each other in average particle diameter and/or particle size distribution.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.