Patent ID: 6727041
Filing Date: 2004-04-27
Classification: B41M,G11B,Y10S

Abstract:
An optical recording medium comprising:a recording layer and an optical reflection layer formed on a light transmitting substrate, wherein the recording layer consists of a trimethine pigment expressed by Structural Formula I, a trimethine pigment expressed by Structural Formula II, and a trimethine pigment expressed by Structural Formula III as follows: wherein Xâ€” is selected from the group consisting of Brâˆ’, Iâˆ’, CIO4âˆ’, BF4âˆ’, PF6âˆ’, and SbF6âˆ’; wherein, A1 is an atomic group selected from the group consisting of Chemical Formulae 1 through 3, and Bl is an atomic group selected from the group consisting of Chemical Formula 4; wherein, R1 is selected from the group consisting of alkyl group, alkoxy group, and aryl group; R2 and R3 are selected from the group consisting of hydrogen atom, alkyl group, alkoxy group, amino group, nitro group, cyano group, aryl group, alkoxycarbonyl group, sulfonylalkyl group, and halogen atom; n is 1 or 2; mis 1, 2, 3, or 4; wherein Xâ€” is selected from the group consisting of Brâ€”, Iâ€”, CIO4âˆ’, BF4âˆ’, PF6âˆ’, and SbF6âˆ’; A2 is an atomic group selected from the group consisting of Chemical Formulae 5 through 8; and B2 is an atomic group selected from the group consisting of Chemical Formula 9; wherein Y1 is selected from the group consisting of hydrogen atom, alkyl group, or halogen atom, wherein, R4 is selected from the group consisting of alkyl group, alkoxy group, and aryl group; wherein, R5 and R6 are selected from the group consisting of hydrogen atom, alkyl group, alkoxy group, amino group, vitro group, cyano group, aryl group, alkoxycarbonyl group, sulfonylalkyl group, and halogen atom; when a molecule contains a plurality of R5 or R6, the R5 or R6 may be either identical substituents or different substituents; n is 1 or 2; m is 1, 2, 3, or 4; wherein Xâ€” is selected from the group consisting of Brâ€”, Iâ€”, CIO4âˆ’, BF4âˆ’, PF6âˆ’, and SbF6âˆ’; A3 is an atomic group selected from the group consisting of Chemical Formulae 10 to 13; B3 is an atomic group selected from the group consisting of Chemical Formulae 14 and 15; Y2 is selected from the group consisting of hydrogen atom, alkyl group, or halogen atom; wherein, R1 is selected from the group consisting of alkyl group, alkoxy group, and aryl group; R8 and R9 are selected from the group consisting of hydrogen atom, alkyl group, alkoxy group, amino group, nitro group, cyano group, aryl group, alkoxycarbonyl group, sulfonylalkyl group, and halogen atom; n is 1 or 2; m is 1, 2, 3, or 4;a singlet oxygen quencher added to the pigments to deactivate singlet oxygen, the singlet oxygen quencher is selected from the group consisting of a nickel metal complex compound, a copper complex compound, a hindered amine compound, an aromatic amine compound, and an aromatic immonium chloride compound; the recording layer having a thickness of 50 to 1000 nm; wherein the recording layer is capable of recording and reproduction with a laser beam having a wavelength from 630 nm to 650 nm; and wherein the optical recording medium has a signal modulation degree of 60% or higher and an unrecorded area has a reflection ratio of approximately 50% when measured with a laser beam having a wavelength of 640 nm.