JPH02294385A - Photochromic sensitized composition and recording medium using same composition - Google Patents

Abstract

PURPOSE:To obtain the title composition useful as recording medium, having excellent stability in a coloring state, comprising a polymer layer containing a benzoindoline-based spiropyran and a polymer phenol compound, etc., in a specific ratio. CONSTITUTION:The aimed composition comprising (A) 1-100 pts.wt. benzoindoline-based spiropyran compound shown by the formula (R<1> is 1-20C alkyl; R<2> to R<5> are H, 1-5C alkoxy, alkyl, halogen, etc.; R<6> is H or 1-5C alkoxy; R<7> and R<9> are H, 1-5C alkoxy, etc.; R<8> is H, nitro, halogen, etc.; R<10> is H, nitro, 1-5C alkoxy, etc.; X is O or S), (B) 100 pts.wt. polymer phenol compound, preferably composed of poly(vinylphenol) and, if necessary, (C) 0-500 pts.wt. binder polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a photochromic photosensitive composition having excellent stability in a coloring state and a recording medium using the same.

Prior Art and Problems When a composition containing a normal spiropyran compound as a photolayer is irradiated with ultraviolet rays, the spiropyran develops color and is recorded, and when heated or irradiated with visible light, the spiropyrene returns to its original state. The record is erased by returning to the erasing body. However, since the thermal stability of the color former of ordinary subiropyran compounds is not high, it has the property of gradually returning to its original colorless state even at room temperature due to the action of heat. Therefore, in an erasable optical recording medium using this photochromic process, it is necessary to improve the thermal stability of colored spiropyran compounds from the viewpoint of record retention, and various proposals have been made. For example, dissociable groups such as hydroxyl groups, carboxylic acid groups, sulfonic acid groups, or 2
Attempts have been made to use so-called reverse photochromic type subirobilane compounds, such as spiropyran compounds with two nitro groups, whose coloring state is stabilized (Japanese Patent Application Laid-open No. 57-65753), and by adding low-molecular-weight phenolic compounds to photosensitive materials. An attempt to improve the thermal stability of the coloring state (Japanese Patent Application Laid-open No. 1983-
No. 154783> etc. are being carried out.

However, the synthesis and production of reverse photochromic subiroviran compounds are complicated and difficult;
In addition, they generally do not have high compatibility with polymeric substances and have problems such as difficulty in obtaining films with high color density.

In addition, when adding low-molecular phenolic compounds to improve thermal stability, the phenolic compound may segregate on the surface of the composition during long-term storage due to insufficient compatibility between the phenolic compound and the polymer binder. It had the following problems.

As a result of intensive studies to solve the above problems, we have developed a stable photosensitizer consisting of a subirobilane compound that has excellent thermal stability in the coloring state by using a polymer compound as the phenol compound. The present invention was achieved by discovering that it is possible to obtain a film of

Structure of the Invention> That is, the present invention comprises (1) (A) 1 to 100 parts by weight of (A) a benzoindoline subviropyran compound, (B) 100 parts by weight of a polymeric phenol compound, and optionally (C) a binder polymer O. It is a photochromic photochromic composition comprising a polymer layer containing ~500 parts by weight.

The present invention will be explained in detail below.

Examples of the penzoindoline spiropyran compound <A) used in the present invention include those represented by the following general formula <I).

Specifically, for example, 6-nitro-8-methoxy-1'
, 3',3'-}limethylspiro[2H-1-penzopyran-2,2'-indoline], 6-chloro-8
-Methoxy-1',3'j'-}limethylsubicu [2H
1-penzopyran-2,2'-indoline], 6-nitro-8-methoxy-1'-brobyl-3'j'dimethylsubiku [2H-1-penzopyran-2,2'-indoline]
, 6-hydroxy-1'. 3',3'-}limethylspiro[2H-1-penzopyran-22'-indoline 1,
Examples include 6,8-dinitro-1',3'j'-trimethylspiro [2H-1-penzobilane-2,2'-indoline].

The polymeric phenolic compound (B) used in the present invention is not particularly limited as long as it has a phenyl group substituted with a hydroxyl group, but specifically, poly(vinylphenol), phenolic resin, etc. etc. can be mentioned. Among these, poly(vinylphenol) is preferred from the viewpoint of coating properties.

The molecular weight of the polymeric phenol compound {B) is 1000 or more. Here, when the binder polymer (C) is not included, the molecular weight of the polymer phenol compound (B) is 5000.
It is preferable that it is above.

1 to 100 parts by weight of the subiropyran compound (A) per 100 parts by weight of these polymeric phenolic compounds (B),
It is preferably added in an amount of 10 to 50 parts by weight. If the amount of the spiropyran compound is less than 1 part by weight, the coloring density of the resulting angry light layer will be low and a photosensitive layer with high contrast will not be obtained, which is not preferable. Further, if the amount of the spiropyran compound exceeds 100 parts by weight, the coloring state cannot be sufficiently stabilized by the polymeric phenol compound, and the coloring density will not increase in proportion to the amount of the spiropyran compound added, which is not preferable.

In the present invention, a binder polymer tc> may be further added as necessary. Here, the binder polymer (C) is not particularly limited as long as it has good compatibility with the subirobilane compound Th (A> and the polymeric phenol compound (B)) and has excellent film-forming properties. Specifically, for example, poly(alkyl acrylate) such as poly(methyl methacrylate), poly(styrene), poly(vinyl acetate), poly(vinyl butyral), cellulose acetate,
Poly(vinyl chloride), poly(vinylidene chloride), vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, poly(propylene), poly(ethylene), poly(
(acrylonitrile), epoxy resin, urethane resin, phenol resin, polyester, etc.

The amount of the binder polymer (C) added at this time is as follows with respect to 100 parts by weight of the polymeric phenol compound:
A suitable range is O to 500 parts by weight, preferably 10 to 500 parts by weight. If the amount added exceeds 500 parts by weight, it is not preferable because a photosensitive layer with high color density cannot be obtained.

The photochromic photosensitive composition used in the present invention, which is composed of a polymer layer containing components (A), (B), and optionally (C), is dissolved in a solvent, coated on a substrate, and dried to form a photosensitive layer. is formed.

Here, the heat of the photosensitive layer is 0.01 to 10 μm, preferably 0.5 to 5 μm.

Examples of solvents include alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone, ethers such as methyl ether, dioxane, and tetrahydrofuran, esters such as ethyl acetate and butyl acetate, and halogens such as chloroform and methylene chloride. In addition, various general-purpose solvents such as benzene, toluene, acetonitrile, dimethylformamide, and mixed solvents thereof are used.

FIG. 1 shows a basic configuration diagram of the erasable optical recording medium of the present invention. FIG. 1-a shows a medium configuration when laser light is irradiated from the recording layer side, in which a light reflective layer (2) is provided on a substrate (1), and a photochromic photosensitive composition of the present invention is further provided on the substrate (1). A recording layer (3) is provided. Then, a protective layer (4) is provided thereon to form a medium. FIG. 1B shows a medium configuration when laser light is irradiated from the substrate side, and the stacking order of the recording layer and the reflective layer is reversed from the former. And in these media,
Reproduction of recording is performed by detecting the presence or absence of recording as a change in reflectance of laser light.

The substrate (1) used in the present invention is not particularly limited, and various types can be used. For example, polycarbonate, poly(methyl methacrylate)
, poly(ethylene terephthalate), glass plates, etc.

As the light-reflecting layer 2), a vapor-deposited film of a metal such as aluminum, silver, or gold, or a vapor-deposited film or coating film of a highly reflective dye is used. Examples of highly reflective dyes used at this time include cyanine dyes, capocyanine dyes, naphthalocyanine dyes, polymethylene dyes, naphthoquinone dyes, and anthraquinone dyes, but are not particularly limited thereto. isn't it. The thickness of these reflective films is 0.1 to 1
A range of μm is suitable.

The protective layer (4) is not particularly limited as long as it has oxygen barrier properties and coating properties, and various polymers can be used.

Various types of light sources can be used in the present invention. Examples include argon laser, helium neon laser, krypton laser, dye laser, ruby laser, excimer laser, semiconductor laser, neobum/yag laser, xenon lamp, mercury lamp, deuterium lamp, and the like.

Effects of the Invention According to the present invention, it is possible to make the subiropyran compound in a colored state exist stably for a long time even at room temperature, so that this photosensitive material can be applied to an erasable recording medium. You will be able to do this.

Furthermore, by using the thermally stable photochromic photosensitive layer thus obtained, it has become possible to provide an inexpensive erasable optical recording medium.

Examples Example 1 As a spiropyran compound, 6-nitro-8-methoxy-1'j',3'-}limethylsubiku [2H1-penzopyran-2,2'-indoline] was converted to poly(4-vinylphenol). (molecular weight 6,000-7,000) was dissolved in methyl isobutyl ketone to a concentration of 30 phr. The obtained solution was applied onto a slide glass and dried to form a photochromic photosensitive layer. The absorption spectrum of the obtained medium is shown in FIG. The medium was colored blue, and it was confirmed that subirobilan was stabilized in a colored state.

When this medium was irradiated with a 633 nm helium-neon laser beam, the irradiated area became discolored and subiropyran became a ring-closed horizontal structure. Next, when the faded area was irradiated with high-pressure mercury lamp light, the faded area returned to its original blue color.

From this, it was confirmed that this photosensitive layer can be used as an erasable recording medium.

Example 2 To a solution obtained in the same manner as in Example 1, poly(methyl methacrylate) was added and dissolved in an amount of 50 phr based on polyvinylphenol.

The obtained solution was applied onto a slide glass and dried to form a photochromic photosensitive layer. The medium was colored blue, and it was confirmed that it was stabilized in a spiropyran colored state.

When this medium was irradiated with 633 nm helium neon laser light, the irradiated area was discolored and the spiropyran was ring closed III.
It became a colorless body. Next, when the faded area was irradiated with high-pressure mercury lamp light, the faded area returned to its original blue color.

From this, it was confirmed that this photosensitive layer became an erasable recording medium.

Example 3 Using 6-chloro-8-methoxy-1',3',3'-}limethylsubikuchi [2H-1-penzobilane-2,2'-indoline] as the spiropyran compound, Example 1
The medium was created in the same manner as. The obtained medium was colored blue, and it was confirmed that it was stabilized in a spiropyran colored state.

When this medium was irradiated with a helium-neon laser beam of 633 nm, the irradiated area was discolored and subirobilan became a decolorized substance with a closed ring structure. Next, when the faded area was irradiated with high-pressure mercury lamp light, the faded area returned to its original blue color.

From this, it was confirmed that this photosensitive layer became an erasable recording medium.

Comparative Example 1 As a subirobilane compound, 6-nitro-8methoxy-
1'. 3'. Equal amounts of 3'-trimethylspiro[2H-1-penzopyran-2.2''-indoline] and bisphenol A as a phenol compound were mixed and dissolved in methyl ethyl ketone.The resulting solution was then applied onto a slide glass and dried. , a photochromic photosensitive layer was formed.

In the obtained photosensitive layer, subiropyran and phenol compounds were segregated, and it was not preferable as a recording layer.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the basic structure of the recording medium of the present invention, in which 1 is a substrate, 2 is a light reflective layer, 3 is a recording layer, and 4
represents a protective layer. FIG. 2 shows the absorption spectrum of the medium of Example 1.

Claims (4)

[Claims] (1) (A) Benzoindoline spiropyran compound 1
~100 parts by weight, (B) polymeric phenol compound 100
Part by weight and if necessary (C) Binder polymer 0~
A photochromic photosensitive composition comprising a polymer layer containing 500 parts by weight. (2) The photochromic photosensitive composition according to claim 1, wherein the polymeric phenol compound (B) is poly(vinylphenol). (3) A recording medium using the photochromic photosensitive composition according to claim 1 as a recording layer. (4) A recording medium using the photochromic photosensitive composition according to claim 2 as a recording layer.