Phenolsulfonic acid aryl ester, developing agent, and heat-sensitive recording material
View Patent ↗The present invention provides a compound represented by the formula (1). The compound represented by the formula (1) is a developing agent superior in both color-developing sensitivity with low energy and image stability [in the following formula, wherein R 1 is a hydrogen atom, an alkyl group, an alkenyl group, an aryl group or an aralkyl group, R 2 in the number of m are each independently an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, a halogen atom, a hydroxy group, a cyano group, a nitro group, a carboxy group or an amino group, R 3 in the number of n are each independently an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, a halogen atom, a hydroxy group, a cyano group, a nitro group, a carboxy group or an amino group, and m and n are each independently an integer of 0-4.
1. A compound represented by formula (1)
where:
R 1 is a hydrogen atom, an alkyl group, an alkenyl group, an aryl group or an aralkyl group,
each R 2 is independently an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, a hydroxy group, a cyano group, a nitro group, a carboxy group or an amino group,
each R 3 is independently an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, a hydroxy group, a cyano group, a nitro group, a carboxy group or an amino group, and
m and n are each independently an integer of 0-4.
2. The compound according to claim 1 , wherein the —CO—OR 1 group is bound to a carbon atom at the 2-position or 4-position of a benzene ring.
3. A developer, comprising the compound according to claim 1 ,
wherein the developer is suitable for a thermal recording material.
4. A thermal recording material, comprising:
a support, and
a thermal recording layer on the support,
wherein
the thermal recording layer comprises a colorless or pale-colored basic leuco dye and a developer for color development of the basic leuco dye, and the developer comprises the compound according to claim 1 .
5. The thermal recording material according to claim 4 , wherein the thermal recording layer comprises at least one sensitizer selected from the group consisting of 1,2-di-(3-methylphenoxy)ethane, fatty acid amide comprising from 10 to 21 carbon atoms, β-benzyloxynaphthalene, diphenylsulfone and p-toluenesulfonamide.
6. The thermal recording material according to claim 4 , wherein the thermal recording layer comprises a hindered phenol compound.
7. The thermal recording material according to claim 6 , wherein the hindered phenol compound is at least one selected from the group consisting of a compound represented by formula (2), a compound represented by formula (3) and a compound represented by formula (4):
where R 5 , R 8 and R 11 are each independently an alkyl group, and R 6 ,R 7 , R 9 , R 10 , R 12 and R 13 are each independently a hydrogen atom or an alkyl group,
where p is 1 or 2.
8. The thermal recording material according to claim 7 , wherein the hindered phenol compound is the compound represented by formula (2), where R 5 , R 8 and R 11 are tert-butyl groups or cyclohexyl groups, R 6 , R 9 and R 12 are methyl groups, and R 7 , R 10 and R 13 are hydrogen atoms.
9. The thermal recording material according to claim 4 , wherein the thermal recording layer comprises a second developer comprising a compound different from the compound according to claim 1 .
10. The thermal recording material according to claim 9 , wherein the second developer comprises at least one compound selected from the group consisting of a bisphenol sulfone compound, a bisphenol compound, a urea compound and a novolac type phenol compound.
11. The compound according to claim 1 , wherein R 1 is an alkyl group comprising 1 to 8 carbon atoms.
12. The compound according to claim 1 , wherein m is 0.
13. The compound according to claim 1 , wherein n is 0.
14. The compound according to claim 1 , wherein both m and n are 0.
15. The compound according to claim 1 , wherein the position of the —CO—OR 1 group in the formula (1) is the 2-position relative to the carbon atom bonded to the oxy group in the benzene ring having the —CO—OR 1 group.
16. The compound according to claim 1 , wherein the position of the —CO—OR 1 group in the formula (1) is the 4-position relative to the carbon atom bonded to the oxy group in the benzene ring having the —CO—OR 1 group.
17. The compound according to claim 1 , wherein the position of the —OH group in the formula (1) is the 4-position relative to the carbon atom bonded to the sulfonyl group in the benzene ring having the —OH group.
18. The compound according to claim 1 , having a formula selected from the group consisting of formulae (a1) to (a26):
19. The compound according to claim 18 , having a formula selected from the group consisting of formulae (a1), (a2), (a3), (a4), (a5) and (a10).
20. The compound according to claim 18 , having a formula selected from the group consisting of formulae (a1), (a2), (a3) and (a5).