Specific dye compound, optical information recording medium comprising specific dye, and information recording method using this optical information recording medium

1. An optical information recording medium comprising:

a disc-shaped substrate, a surface of which has a pre-groove having a track pitch of 0.2 to 0.8 μm; and

a recording layer comprising a recording dye represented by either of the following formulae (V) or (VI) on the surface of the substrate having the pre-groove:

wherein R 1 and R 2 each independently represent a substituent, p and q are each an integer of 0 to 3, m represents a number of valence bonds between 2 to 4, and when m=2 V is selected from the group consisting of a 2,3-naphthylene group, a 1,5-naphthylene group, a 3,4-thiophenylene group, a 5,6-benzthiazolylene group, and a 2,6-pyridinylene group each of which may have a substituent; when m=3 V is selected from the group consisting of a benzene-1,3,5-triyl group and a 2,4,6-pyridinylene group each of which may have a substituent; and when m=4 V is a benzene-1,2,4,5-tetrayl group which may have a substituent,

wherein R 1 , R 2 , p, q, V and m represent the same definitions as those of R 1 , R 2 , p, q, V and m in formula (V), respectively.

2. The optical information recording medium of claim 1 , wherein in both formulae (V) and (VI), V represents a benzene-1,3,5-triyl group, a benzene-1,2,4,5-tetrayl group or a 2,4,6-pyridinylene group, which may have a substituent, respectively.

3. The optical information recording medium of claim 1 , wherein in both formulae (V) and (VI), m represents an integer of 3 and V represents a benzene-1,3,5-triyl group or a 2,4,6-pyridinylene group, which may have a substituent, respectively.

4. The optical information recording medium of claim 1 , further comprising a light-reflective layer made of a metal, between the recording layer and the surface of the substrate having the pre-groove.

5. The optical information recording medium of claim 4 , further comprising a protective layer on the recording layer.

6. A method for recording information onto an optical information recording medium, the optical information recording medium comprising:

a disc-shaped substrate, a surface of which has a pre-groove having a track pitch of 0.2 to 0.8 μm; and

a recording layer comprising a recording dye represented by either of the following formulae (V) or (VI) on the surface of the substrate having the pre-groove:

wherein R 1 and R 2 each independently represent a substituent, p and q are each an integer of 0 to 3, m represents a number of valence bonds between 2 to 4, and when m=2 V is selected from the group consisting of a 2,3-naphthylene group, a 1,5-naphthylene group, a 3,4-thiophenylene group, a 5,6-benzthiazolylene group, and a 2,6-pyridinylene group each of which may have a substituent; when m=3 V is selected from the group consisting of a benzene-1,3,5-triyl group and a 2,4,6-pyridinylene group each of which may have a substituent; and when m=4 V is a benzene-1,2,4,5-tetrayl group which may have a substituent,

wherein R 1 , R 2 , p, q, V and m represent the same definitions as those of R 1 , R 2 , p, q, V and m in formula (V), respectively,

the method comprising:

providing a laser that emits light having a wavelength equal to or less than 440 nm, and

using the laser to record information on the optical information recording medium.

7. The information recording method of claim 6 , wherein the optical information recording medium further comprises a light-reflective layer made of a metal, between the recording layer and the surface of the substrate having the pre-groove.

8. The information recording method of claim 7 , wherein the optical information recording medium further comprises a protective layer on the recording layer.

9. The information recording method of claim 8 , wherein the laser emits light having a wavelength of 405 nm.

10. A dye compound represented by either of the following formulae (V) or (VI):

wherein R 1 and R 2 each independently represent a substituent, p and q are each an integer of 0 to 3, m represents a number of valence bonds between 2 to 4, and when m=2 V is selected from the group consisting of a 2,3-naphthylene group, a 1,5-naphthylene group, a 3,4-thiophenylene group, a 5,6-benzthiazolylene group, and a 2,6-pyridinylene group each of which may have a substituent; when m=3 V is selected from the group consisting of a benzene-1,3,5-triyl group and a 2,4,6-pyridinylene group each of which may have a substituent; and when m=4 V is a benzene-1,2,4,5-tetrayl group which may have a substituent,

wherein R 1 , R 2 , p, q, V and m represent the same definitions as those of R 1 , R 2 , p, q, V and m in formula (V), respectively.

11. The dye of claim 10 , wherein in both formulae (V) and (VI), m represents a number of valence-bond and V represents an aromatic ring selected from the group consisting of a benzene-1,3,5-triyl group, a benzene-1,2,4,5-tetrayl group, and a 2,4,6-pyridinylene group, which may have a substituent.

12. The dye of claim 10 , wherein in both formulae (V) and (VI), m represents an integer of 3 and V represents an aromatic ring selected from the group consisting of a benzene-1,3,5-triyl group and a 2,4,6-pyridinylene group, which may have a substituent.

13. The dye of claim 12 , wherein the dye is selected from the group consisting of the following Compounds 21 to 30 and 35 to 40:

Compound

R

R 1

R 2

21

CH 3

Bu(t)

CH 3

22

CF 3

Bu(t)

CH 3

23

CN

Bu(t)

CH 3

24

CO 2 CH 3

Bu(t)

CH 3

25

COPh

CH 3

CH 3

26

COCH 3

CH 3

CH 3

27

SPh

Bu(t)

CH 3

28

SO 2 Ph

Bu(t)

Bu(t)

29

OCH 3

CH 3

OCH 3

30

N(CH 3 ) 2

H

CH 3

Compound

R

X

35

CO z CH z CH 3

CH

36

COPh

CH

37

SPh

CH

39

Cl

N

40

CF 3

CH.