# US 5,705,635 A · Method for the preparation of ultrafine fibrous assembly having twisted morphology

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,705,635 A
- Document ID: US5705635A
- Status: Granted
- Kind: A
- Application number: 08/752,437
- Filed: 1996-11-14
- Granted: 1998-01-06
- Earliest claimed: 1995-11-20
- Assignees: Japan as represented by Director General of Agency of Industrial Science and Technology
- Inventors: Toshimi Shimizu; Mitsutoshi Masuda
- Web page: https://patentgrep.com/patent/US5705635A

## CPC

- C07H 1/00: Processes for the preparation of sugar derivatives
- C07H: SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS (derivatives of aldonic or saccharic acids C07C, C07D; aldonic acids, saccharic acids C07C59/105, C07C59/285; cyanohydrins C07C255/16; glycals C07D; compounds of unknown constitution C07G; polysaccharides, derivatives thereof C08B; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification C12N15/00; sugar industry C13)

## Abstract

When a saturated aqueous solution of a bolaform glycolipid represented by the general formula G--NH--CO--(CH.sub.2).sub.n --CO--NH--G, in which G is a residue derived from a D- or L-glucopyranose by excepting the reduced-terminal hydroxyl group and the subscript n is 10, 12 or 14, at a high temperature, e.g., 90 .degree. C. or higher, is cooled at a controlled rate of 0.5 .degree. C./minute or lower, crystallite growth of the precipitates proceeds to form an ultrafine fibrous assembly of up to several hundreds .mu.m length having a twisted fibrous morphology of right- or left-hand screw. The twisted fibrous assembly thus obtained has usefulness as a functional material in the field of fine chemicals and in the fields of electronic and information technologies.

## Claims

### Claim 1

A method for the preparation of an ultrafine fibrous assembly having a twisted morphology which comprises the steps of:
(a) dissolving, in water, a glycolipid represented by the general formula
G--NH--CO--(CH.sub.2).sub.n --CO--NH--G,
in which G is a residue derived from a D- or L-glucopyranose by excepting the reduced-terminal hydroxyl group and the subscript n is a positive number of 10, 12 or 14, to form an aqueous solution which is heated at a temperature of 90.degree. C. or higher; and
(b) cooling the aqueous solution at a rate not exceeding 0.5.degree. C. per minute down to a temperature not higher than 30.degree. C. so as to effect growth of crystallites.

### Claim 2 (depends on 1)

The method for the preparation of an ultrafine fibrous assembly having a twisted morphology as claimed in claim 1 in which the cooling rate of the aqueous solution in step (b) does not exceed 0.1.degree. C. per minute.

### Claim 3 (depends on 1)

The method for the preparation of an ultrafine fibrous assembly having a twisted morphology as claimed in claim 1 in which the amount of the glycolipid added to water in step (a) is sufficient to give a saturated aqueous solution thereof at a temperature of 90.degree. C. or higher.