Heat resistant herapathite and process for producing the same
US5368780A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Nov 14, 1991 |
| Grant date | Nov 29, 1994 |
| Priority date | — |
| Expiry date | Nov 14, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B29/54
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A herapathite has a capillary crystal form in which its iodine atoms are oriented in a major axis direction of the capillary crystal form. The herapathite obtained is expressed by a chemical formula, xC.sub.20 H.sub.24 N.sub.2 O.sub.2.yH.sub.2 SO.sub.4.zHI.sub.3, in which a ratio of a number of the sulfuric acid molecules (y) with respect to a number of the iodine atoms (3z), i.e., (y/3z), is less than 0.5. The production process includes a reaction step, a first separating step, a recrystallizing step and a second separating step. A solvent used in the recrystallizing step is at least one of water and alcohol. A mixing weight ratio of water with respect to alcohol of the solvent is more than 50/50 or less than 10/90. The herapathite does not degrade even after it is heated up to 130.degree. C., and it is applicable to an automobile light shielding glass which should show a high transparency when a voltage is applied thereto.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.