Claims
- 1. A information recording disk medium comprising:
- a pair of disk-shaped substrates disposed in parallel to each other;
- information bearing layers made of a cyanine dye and formed respectively on surfaces of said pair of substrates which face each other, from which information is read by irradiating a light beam such as a laser beam thereon;
- an inner spacer concentrically interposed between said pair of substrates at a central part of said substrates so as to form a hollow space between said information bearing layers facing each other;
- an outer spacer concentrically interposed between said pair of substrates at a peripheral portion thereof; and
- polyurethane adhesive layers having a viscoelastic characteristic and respectively connecting said pair of substrates with said inner and outer spacers.
- 2. A information recording disk medium as set forth in claim 1 wherein the disk-shaped substrates are made of polymetyl metacrylate.
- 3. A information recording disk medium as set forth in claim 2 wherein an acrylic resin is used as the material for the inner and outer spacers.
- 4. A information recording disk medium as set forth in claim 3 wherein each polyurethane adhesive layer made of polyurethane is prepared by a reaction of an isocyanate and a polyol.
- 5. A information recording disk medium as set forth in claim 4 wherein the polyurethane adhesive has the following general formula: ##STR3##
- 6. A information recording disk medium as set forth in claim 5 wherein the polyol is the castor oil or the polyethylenglycol [HO(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2 CH.sub.2 OH].
- 7. A information recording disk medium as set forth in claim 1 wherein the cyanine dye is 2-{7-[1,3-Dihydro-1,1-dimethyl-3-(4-sulfobutyl)benz(e)indolin-2-ylidene]-1,3,5-heptatrienyl}-1,1-dimetyl-3-(4-sulfobutyl)-1H-benz(e)indolium hydroxide inner salt sodium salt, which is expressed by the following structural formula: ##STR4##
Priority Claims (1)
Number |
Date |
Country |
Kind |
60-011997[U] |
Jan 1985 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 824,130, filed Jan. 30, 1986 abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4600625 |
Abe et al. |
Jul 1986 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
8201556 |
Nov 1982 |
NLX |
2087129 |
May 1982 |
GBX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
824130 |
Jan 1986 |
|