JPH0312646A - Novel dyestuff recording material - Google Patents

Abstract

PURPOSE:To improve sensitivity and recording and reproducing characteristics by providing a layer contg. a specific light absorbing agent right under a metal silver-contg. layer formed by reaction of a silver compd. in the presence of the developing nuclei of silver or the metal nobler than the silver. CONSTITUTION:The layer contg. the light absorbing agent substantially having absorbance in a semiconductor laser wavelength region right under the metal silver-contg. layer formed by reaction of the silver compd. in the presence of the developing nuclei of the silver or the metal nobler than the silver exists in this optical recording material. The respective layers of the reflective metal silver-contg. layer and silver-supplying layer of the optical recording material may have or may not have a distinct boundary. The smaller thickness of the recording layer itself provided with the metal silver-contg. layer and the silver- supplying layer in combination is more preferable in terms of the improvement in the recording density and the reduction of the cost as far as the difference of the reflectivity is obtd. The digital recording material which has the good sensitivity of the laser recording and the good recording and reproducing characteristics is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides a new digital recording material that can be written and read mainly by laser light.

(Prior Art) In recent years, laser-related technology has made remarkable progress, information has been digitized, and various new optical recording materials necessary for this have been proposed.

Typical digital recording materials include optical discs. Optical discs using zero dyes have been attracting attention and being developed because they have the advantage of being inexpensive to manufacture.

In addition, an optical card material has been proposed that is high-density and can be carried around at all times as a material that can be easily handled. A well-known example of this is the optical card developed by Drexler, which is described in Japanese Patent Laid-Open No. 59502139 and Japanese Patent Laid-open No. 58-188346.

Furthermore, various companies are developing optical card materials using materials similar to those used for optical disks. On the other hand, optical tape has been proposed as a material that is more compact than optical disks and can record a large amount of information.

Although several systems and materials have been proposed, there are problems with writing sensitivity, storage stability of recording materials, recording density,
The characteristics necessary for recording materials, such as error rate, are still insufficient.

Therefore, the present inventors have previously proposed a material that has excellent storage stability under high temperature conditions and can be used satisfactorily as an optical recording material even under usage conditions such as bending.

(Problems to be Solved by the Invention) The present invention provides a material with better sensitivity and better reading characteristics, that is, improved C/N ratio and error rate.

Furthermore, the present invention provides an optical recording material with good stability.

The material of the present invention is of a coating type and can be manufactured continuously, so it is possible to provide an inexpensive optical recording material.

(Means for solving the problem) Optical technology using an optical recording material that forms a reflective metallic silver-containing layer by utilizing the reduction reaction of silver compounds when heated, and a light absorbing agent (dye). In combination with the recording material, the silver in the reflective metallic silver-containing layer absorbs light and generates heat during recording, and the dye absorbs weak light during reading to improve reading characteristics. In order to provide a mechanism that improves the performance, we separated the functions and made them highly functional.

It was surprising how many functions were unexpectedly improved. That is, sensitivity has been improved, gamma characteristics during recording have been improved by selecting a dye, contrast ratio has been increased during reading, and reading characteristics have also been improved. It was also surprising that the stability of the material was also greatly improved.

Such an optical recording material of the present invention can be defined as follows.

Immediately below the metallic silver-containing layer formed by the reaction of a silver compound in the presence of silver or metal development nuclei nobler than silver,
This is an optical recording material in which there is a layer containing a light absorber having a substantial absorbance in the wavelength range of a semiconductor laser.

In this case, whether or not the reflective metallic silver-containing layer and the silver supply layer in this optical recording material have clear boundaries is not important as an optical recording material. However, in order to improve the recording density as an optical recording material, metallic silver must be present uniformly dispersed as a small dispersion with a diameter of at least 2 to 3 μm.
It is preferable to use a metal tall that can be handled as a uniform continuous film on the order of 3 μm.

The thickness of the recording layer itself, which is a combination of the metallic silver-containing layer and the silver supply layer of this optical recording material, is such that as long as a difference in reflectance can be obtained, the thinner the recording layer, the higher the recording density and the lower the cost. Although it is preferable, it is usually set to about 1 to 25 μm.

The light absorber is contained in the silver supply layer and is present directly below the metallic silver containing layer. Furthermore, if the metallic silver-containing layer does not have a clear boundary line, there is no problem even if the metallic silver-containing layer contains a light absorbent.

Silver compounds can be roughly divided into three types, including six examples of organic silver salts and carboxylic acid silver-containing polymers.

■ Silver salts of long-chain fatty acids, ■ Organic solvent-soluble silver compounds, and ■ Polymers containing silver carboxylate.

As silver salts of long-chain fatty acids, silver salts of stearic acid, silver salts of behenic acid, and the like are particularly useful. However, other non-photosensitive silver salts such as silver saccharate, benzotriazole, etc. can also be used.

As the organic solvent-soluble silver compound, those soluble in organic solvents are selected from aliphatic carboxylic acid silver salts and silver metal chelate compounds. For example, as a preferable aliphatic carboxylic acid silver, fluorine-containing aliphatic carbon ea silver is used.

Further, as the tin metal chelate compound, a fluorine-containing chelating agent, typified by a fluorine-containing β-diketone, is generally used.

Particularly preferred compounds include trifluoroacetic acid dicarboxylate, silver hebutafluorobutyrate, silver perfluorooctanoate, silver trifluoromethanesulfonate, silver furoyl trifluoroacetonate, silver hexafluoroacetylacetonate, and silver hexafluoroacetylacetonate. Mention may be made of fluorobutanoyl bivanoyl methanate, silver pivaloyl trifluoroacetonate, silper trifluoroacetylacetonate, and silver furoyl trifluoroacetonate.

The organic solvent soluble silver compound is - relative to the organic solvents 1d, such as alcohols, ketones, ethers, nitriles, halogens, aliphatic, aromatic, etc. used numerically,
Those that can dissolve 1 mg or more are preferred.

The silver carboxylic acid-containing polymer can be synthesized from a natural or synthetic polymer compound having a carboxylic acid in a polymer side chain. Among them, particularly useful silver carboxylate-containing polymers include silver salt compounds derived from natural products such as silver alginate and silver pectate, silver polyacrylate,
It can be selected from silver compounds derived from synthetic polymers such as polysilver methacrylate.

Regarding synthetic polymers, copolymers with various types of heptamines such as acrylic acid, methyl methacrylate, acrylonitrile, vinyl chloride, and vinyl acetate are particularly useful because they can be used as bases for silver-containing polymers. be.

In order to form a reflective metallic silver-containing layer using (2) a silver salt of a long-chain fatty acid and (2) an organic solvent-soluble silver compound, an appropriate reducing agent is essential. When using a silver carboxylate-containing polymer, a reducing agent may or may not be introduced, but if necessary, a reducing agent may be incorporated into the carboxylate-containing polymer by various methods.

As the reducing agent for the silver compound, any agent may be used as long as it can reduce the silver compound. Examples of preferred reducing agents include inhibiting phenols in which a sterically bulky group is bonded to the carbon adjacent to the carbon to which the hydroxyl group is bonded, sterically inhibiting the hydroxyl group;
For example, 26-di-t-butyl-4-methylphenol, 2゜2゛-methylenebis-(4-methyl-6-t-butylphenol), 2.2°-methylenebis-(4-ethyl-6-t-butylphenol) ), 2゜4.4-)limethylbentylbis(2-hydroxy-3,5-dimethylphenyl)methane, 2゜5-di-butyl-4
-methoxyphenol, 2-t-butyl-6-(3-t
-butyl-2-hydroxy-5-methylbenzyl)-4
-Methylphenyl acrylate, 4.4"-butylidene-bis=(3-methyl-6-t-butylphenol, triethylene glycol-bis-(3-(3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanethiolubis(3-(3,
5-di-L-butyl-4hydroxyphenyl)propionate], 24-bis-(n-octylthio)-6-(
4-Hydroxy-3,5-di-butylanilino)-
1,3,5-) riazine, benquerythrityltetrakis-(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate L2゜2-thio-diethylenebis(3-(3,5- di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3
, 5-di-butyl-4-hydroxyphenyl)propionate, 2,2-thiobis(4-methyl-6~t-
butyl fininol), N-N'-hexamethylenebis(3,5-di-butyl-4-hydroxy-hydrocinnamamide), 3,5-di-t-butyl-4-hydroxy-benzylphosphonate-diethyl ester, 1,3
．． 5-) Limethyl-2゜4.6-tris(3,5-di-butyl-4-hydroxybenzyl)benzene, bis(ethyl 3,5-di-butyl-4-hydroxybenzylphosphonate) calcium, tris- (3,5-G1
-Butyl-4-hydroxybenzyl)-isocyanurate, N,N'-bis(3-(3,5-',;-L-7'
Examples include chloro-4-hydroxyphenyl)propionyl)hydrazine.

In addition, reducing agents for silver salts such as hydroquinone, 2.5-dimethylhydroquinone, chlorohydroquinone, p-aminophenol, methylhydronaphthalene, phenidone, methyl gallate, p-phenyldenol, bisphenol A, 2.4- Dihydroxy acids, aromatic acid, and p-methoxyphenol can also be used. The amount of reducing agent varies depending on the type of reducing agent, etc., but for boat fishing, it is about 10 moles, about 0.01 mmole per 1 mole of silver compound,
Preferably from about 0.1 mol to about 3 mol.

The light absorbent used in the present invention is a light absorbent having absorbance in the semiconductor laser wavelength range. This condition is
This is a condition when the light absorber is introduced into the material, and does not define the absorption wavelength range of the light absorber itself. The wavelength range of the semiconductor laser here is 650 nm to 900 nm.
It is. Further, having substantial light absorption is defined as having a difference in reflectance of 5% or more between the light absorber-added system and the light absorber-free system when pits are formed. If it is less than 5%, there will be little improvement in reading characteristics and no improvement in photostability.

As this light absorbing agent, various dyes can be mentioned.
Cyanine pigments, merocyanine pigments, styryl pigments, styrylquinoline pigments, phthalocyanine pigments, naphthalocyanine pigments, suaryllium pigments, oxonol pigments, xanthine pigments, triphenylmethane pigments, croconium pigments, azulenium pigments Examples include dyes, naphthoquinone dyes, anthraquinone dyes, thiol nickel complex dyes, hemicyanine dyes, logcyanine dyes, and the like.

Preferably, a light absorber having good weather resistance to light in the wavelength range of a semiconductor laser is used, and examples thereof include phthalocyanine dyes, naphthalocyanine dyes, thiol nickel complex salt dyes, and azulenium dyes.

Next, specific examples will be given, but the invention is not limited to these. Aluminum phthalocyanine, copper phthalocyanine, iron phthalocyanine, cobalt phthalocyanine, nickel phthalocyanine, titanium phthalocyanine, fluorinated aluminum phthalocyanine, magnesium phthalocyanine, cobalt naphthalocyanine, nickel naphthalocyanine, titanium naphthalocyanine, magnesium naphthalocyanine, fluorinated alumina phthalocyanine, zinc phthalocyanine, Examples include ethylene 1,2-dithiol-based nickel complexes.

The silver compound, reducing agent, and light absorbing agent are usually dissolved or dispersed together with the polymer compound in a solvent to prepare a uniform coating solution, except when a polymer containing silver carboxylate is used.

Is the solvent alcohol-based such as methanol, ethanol, isopropyl alcohol? 8 Medium; Ketone solvents such as 2-butanone and acetone; Ester solvents such as ethyl acetate; Aromatic or alicyclic hydrocarbon solvents such as toluene, xylene, and cyclohexane; Halogen organic solvents such as chloroform and dichloroethane, etc. Examples include organic solvents.

Here, the selection of a polymer compound as a binder is not only important in creating a stable coating solution, but also has a large effect on the storage stability of the optical recording material obtained after coating, drying, and heat development. It is extremely important to give.

Hydrophilic binders such as gelatin, polyvinyl alcohol, etc. should be avoided in order to provide more favorable stability, especially under high humidity storage conditions.

Preferred binders in the present invention may be appropriately selected from a wide range of hydrophobic organic polymer compounds such as polymethyl methacrylate, polyvinyl formal, polyvinyl butyral, vinyl chloride-vinyl acetate copolymer, cellulose acetate, and polystyrene. can. The hydrophobic binder is in a weight ratio of about 10:1 to about 1:10 to the organic solvent soluble silver compound.

When using a silver carboxylate-containing polymer, it may be prepared by uniformly dissolving or dispersing the silver carboxylate-containing polymer in a solvent, coating it on a suitable support and drying it, or
A carboxylic acid salt-containing polymer containing metal salts such as sodium, potassium, ammonium, and lithium is uniformly dissolved, coated uniformly on a suitable support, dried, and then coated with a suitable soluble source such as an aqueous silver nitrate solution. Silver carboxylate-containing polymers may be formed and prepared by providing a layer. In this case, the light absorber may be introduced by being dissolved or dispersed in a solvent together with the carboxylic acid group-containing polymer, or may be introduced together with the carboxylic acid salt-containing polymer. Further, if the light absorbing agent is soluble, it can also be introduced by introducing it together with a suitable soluble silver source such as an aqueous silver nitrate solution and allowing it to permeate into the coating layer of the carboxylate polymer.

The reflective metallic luster layer of the present invention is manufactured as follows. That is, ζi metal development nuclei are formed on a layer (optical recording material composition layer) containing a silver compound, a light absorber, a reducing agent, etc., which has been coated in advance, and then under suitable heating conditions, for example, at least 70'C or higher. When heated at a high temperature for several seconds to several minutes, a reflective metallic silver-containing layer is formed on the surface layer. The heating temperature is preferably 200° C. or lower in consideration of the heat resistance of the support and ease of handling in production. In order to form this reflective metal silver-containing layer, metal development nuclei that act catalytically are essential.

The metal development nucleus is silver or a more noble metal species. Metals more noble than silver include palladium, platinum, gold,
Examples include rhodium, ruthenium, thallium, and mercury. These metal nuclei may be a single metal species, or may be a composite system or a compound such as silver sulfide or silver oxide.

The method for forming metal development nuclei on the surface of the optical recording material composition includes a method in which the metal development nuclei are dispersed in a solvent containing a suitable binder and coated on the surface of the optical recording material composition, or a method such as vapor deposition. It is also possible to form metal catalyst nuclei on the surface under gas phase conditions. Alternatively, the surface may be coated with a strong reducing agent or the surface may be exposed to a reducing gas such as hydrogen gas for a short time to form metal development nuclei consisting of the metal species itself on the surface.

For example, typical manufacturing methods include a method in which the surface layer is sequentially immersed in an aqueous solution of stannous chloride and an aqueous solution of palladium chloride, and a metal nucleus is applied by electroless plating in which the metal nucleus of palladium is applied to the surface layer; Examples include a method in which metals such as platinum, gold, silver, and palladium are vacuum-deposited on the surface.

Further, a compound that forms silver sulfide nuclei, such as sodium sulfide, may be disposed on the surface layer. Alternatively, silver metal development nuclei may be provided on the surface by exposing the surface to a reducing gas such as hydrogen gas for a short time. It is necessary to select an appropriate forming method depending on the type of silver compound, binder, etc.

When an optical recording material composition layer having such a surface layer is heated under appropriate heating conditions, for example, at a temperature of at least 70° C. for several seconds to several minutes, a reflective metallic silver-containing layer can be formed on the surface. .

Appropriate heating conditions are preferably 90 to 200°C and about 2 to 100 seconds. These heating conditions must be controlled to optimal conditions in order to satisfy the structure of the present invention. In particular, care must be taken because excessive development tends to cause the reflective metallic silver-containing layer to become non-uniform.

The optical recording material of the present invention can contain various additive components to enhance the intended performance of the material. For example, it is possible to introduce a compound that controls the size of silver particles in the metallic silver-containing layer. Examples include toning agents such as phthalazinone used in dry silver salt sensitive materials. Further, an anti-fogging agent, a sensitizer, etc. can be added as necessary.

Furthermore, in the present invention, it is possible to incorporate photosensitive silver halide into the optical recording material composition, and by such combination, preformat processing can be performed by performing pattern exposure through a mask in advance during manufacturing. It turned out that it was easy to do.

Such a change in composition can be achieved by applying a halogen ion source to part of the silver carboxylate-containing polymer and converting part of the organic solvent-soluble root compound into photosensitive silver halide in advance, or by separately preparing a polymer. There is a method of dispersing the silver halide microcrystals in an optical recording material composition.

The optical recording material of the present invention is provided with a transparent protective layer for the purpose of protecting the recording layer. This protective layer is selected from highly transparent organic polymer compounds such as polycarbonate, polystyrene, polymethyl methacrylate, polyvinyl chloride, polyvinylidene chloride, and polyethylene terephthalate.

Further, the back surface of the optical recording material layer may consist only of a base film to which the optical recording layer is applied, or may further include a reinforcing layer against bending, etc., on the back surface. Further, the surface of the transparent protective layer is usually treated to make it less likely to be scratched.

The shape of the present invention is generally card-shaped, but it may also be partially disk-shaped or tape-shaped.

The optical recording material of the present invention can be recorded with various laser light sources having appropriate power, typical examples of which are He-Ne lasers and semiconductor lasers. For example, using a semiconductor laser of about 10 mW, 2 to 3
It is possible to write at a speed of several tens of cm/sec with a beam diameter of μm.

The optical recording material of the present invention can be used as a so-called write-once type recording material, and the user can write on it as needed, and once it has been written, it cannot be erased, so it can be used in applications where evidence is required. It can also be used for In addition, you can write information in advance and make it read-only.
It can also be used as an OM card.

Examples are described below to explain the present invention in more detail, but the present invention is not limited thereto.

Examples 1-6 A suspension consisting of the following components was prepared.

Behenic acid root 20g polyvinyl butyral
18g 8g Phthalazine 4g
2.2-methylenebis(4-ethyl-6-t-butylphenol) 9g 2-butanone
200g toluene
60g light absorber (see Table 1) 2mg
Sodium bromide 1g dichloromethane 5g methanol
The Ig suspension was homogenized by a ball mill for about 12 hours and then passed through a filter with an average pore size of 1.5 μm to remove undispersed materials.

This suspension is applied after drying with a small applicator.
Select the slit so that it is μm, apply it uniformly to 1100II polyester terephthalate (PET),
After drying at a temperature of 22° C. and a humidity of 50% RH, this sample was immersed in the following aqueous solutions for 10 seconds each, washed with water, and air-dried.

(Aqueous solution 1) Stannous chloride 7g Distilled water
200m concentrated hydrochloric acid
4d (aqueous solution 2) Palladium chloride 0.1g distilled water
200d concentrated hydrochloric acid
After exposing the obtained 5 ml samples to light for formatting, they were incubated at 130°C for 1 hour.
When heated for 0 seconds, silver was deposited on the surface layer of the unexposed area, forming a reflective metallic silver-containing layer. The exposed area formed a low reflection area.

Next, these samples were exposed to semiconductor laser light with an emission wavelength of 830 nm (beam diameter 3 μm, emission power 10
A writing test was performed using When pulse oscillation was performed at a scanning speed of 40 cm/sec, pits were formed.

Measure the C/N ratio of the reproduced signal for each example,
Furthermore, the bit error rate was measured using a commercially available error detector. Playback power is 0. The power was 5 mW. The results are shown in Table 2.

Table 2 also shows the minimum power required to form pits when recording was performed under the above recording conditions by changing only the laser emission power.

In addition, halogen lamp 2 under constant temperature of 40℃ and 90%
An accelerated test was conducted under the condition of 0.00'01ux irradiation.

The results of the 100-hour accelerated test are also shown in Table 2.

Comparative Example 1 An experiment was conducted in exactly the same manner as Examples 1 to 6. However, the results are shown in Table 2 without adding a light absorber.

Comparative examples 2 to 4 A solution consisting of the following components was prepared.

Light absorber (pigment) 1g polyvinyl butyral
0. 005g dichloroethane
20g ethanol
After homogenizing 20 g of this solution, it was passed through a filter with an average pore size of 1.5 μm. Thereafter, it was spin-coded onto a disc-shaped base made of acrylic resin. The subsequent recording and evaluation methods were the same as in Examples 1-6.

The light absorbers used are also shown in Table 1.

Table 1 Examples 7-12 A solution consisting of the following components was prepared.

Silver trifluoroacetate 20g2.2-methylenebis(4-ethyl-6-t-butylphenol)
9g 2-butanone 200g methanol
1g toluene
60g chloroform 1
0g polycarbonate 20g light absorber (see Table 3) 2mg This solution is
After being homogenized by a ball mill for about 6 hours, it was passed through a filter with an average pore size of 1.5 μm.

This solution was dried using a spin coater and then applied to a polycarbonate substrate under conditions such that the thickness was 6 μm. After that, the temperature was 22℃? It was dried under the conditions of W degree and 50% RH. This polycarbonate substrate had metal development nuclei, that is, palladium nuclei, formed on its surface in advance using the following catalyst nucleation method for electroless plating manufactured by Nippon Sailing Co., Ltd.

The method is shown below. The polycarbonate substrate was sequentially immersed in the following aqueous solutions for 10 seconds each, then washed with water and air-dried.

(Aqueous solution 1) Activator Neo Gant 834 40d (Nippon Sailing Co., Ltd. trade name) Distilled water 956 ml Sodium hydroxide 3 g (Aqueous solution 2) Reducer Neo Gant WA 5rtdl (
Product name of Nippon Sailing Co., Ltd.) Boric acid 5g Distilled water
Each sample obtained at 950d was heated at 150'C for 60 seconds.

These samples had a glossy layer due to the precipitation of silver on the surface layer (the interface between the coating layer and the base). Next, add 830n to the sample.
Semiconductor laser light with an emission wavelength of m (beam diameter 4μ
A writing test was conducted using m1 light emitting power (12 mW). When the scanning speed was set to 60C11/sec and pulse oscillation was performed, pits were formed.

C/N and error rate were measured for each example in the same manner as Examples 1 to 6. The results are shown in Table 4.

Table 4 also shows the minimum power required to form pits when recording was performed under the above recording conditions by changing only the laser emission power.

In addition, constant temperature V of 40℃ 190%! An accelerated test was conducted under the conditions of irradiation of 20,0001 ux using a halogen lamp. The results are also shown in Table 4.

Comparative Example 5 An experiment was conducted in exactly the same manner as in Examples 7 to 12. However, Table 4 shows the results when no light absorber was added.

Table 3 Examples 13-18 A solution consisting of the following components was prepared.

C hcOOAg 20
g Polyvinyl butyral
18g2-tert-butyl-6-
(3-t-butyl-2-hydroquine-5-methylbenzene)-4-methylphenyl 7-acrylate
8 g isopropyl alcohol 185 g cyclohexane 55 g chloroform
20g sodium bromide
0.3g Cobalt iodide 0.3g
Light absorber (see Table 3) 3 mg This solution, after being homogenized by ball milling for about 8 hours, has an average pore size of 1. It was passed through a 5 μm filter.

Thereafter, it was applied and dried under the same conditions as in Examples 1 to 6.

However, the coating was applied so that the film thickness after drying was 11 μm, and was dried under a red safety light. Palladium was adsorbed onto the surface of this window material in the same manner as in Examples 7 to 12.

After that, exposure is performed to create formatting, and 1
When heated with a block heater at 50° C. for 10 seconds, silver precipitated on the surface of the unexposed area, forming a metallic luster layer and forming formatting.

Next, using a semiconductor laser beam with an emission wavelength of 830 nm (beam diameter 3 μm, emission power 11 mW),
I did a writing test.

When pulses were transmitted at a scanning speed of 50 cm/sec, pits were formed. For each Example, the C/N ratio and error rate were measured in the same manner as Examples 1 to 6. The results are shown in Table 5.

Table 5 also shows the minimum power required to form bits when recording was performed under the above recording conditions by changing only the laser emission power.

Further, an acceleration test was conducted under the condition of constant temperature of 40°C 190% and irradiation of 20,0001 uX with a halogen lamp. The results are also shown in Table 6.

Comparative example 6 The experiment was conducted in exactly the same manner as in Example 13-1.

However, no light absorber was added. The results are shown in Table 5.

Examples 19-24 A solution consisting of the following components was prepared.

Sodium alginate 20g distilled water
800g isopropyl alcohol 60g light absorber (see Table 1)
2 mg of this solution was homogenized by a ball mill for about 5 hours and then passed through a filter with an average pore size of 1.5 μm.

After drying this solution in a small applicator, 6μ
Select slits so that the diameter of
It was dried under conditions of humidity and RH of 50%.

Then 0. This sample was immersed in an aqueous solution of IN silver nitrate to form silver alginate.

Next, the sample was sequentially immersed for 10 seconds each in a 6th order aqueous solution in which metal development nuclei, that is, palladium plating, were formed on the surface using a catalyst nucleation method for electroless plating manufactured by Nippon Sailing Co., Ltd., and then washed with water. Air dried.

(Aqueous solution 1) Activator Neogant 834 40 all (
Nippon Sailing Co., Ltd. (Product name) Distilled water 956d Sodium hydroxide 3g (1 liter of water - 2 ml)
) Reducer-Neogant WA 5d (Nippon Sailing Co., Ltd. product name) Boric acid 5g Distilled water
Each sample obtained at 950 d was heated at 150° C. for 100 seconds.

The sample has a metallic silver-containing layer (glossy layer) with silver precipitated on the surface layer.Writing was performed on the sample using a semiconductor laser beam with an emission wavelength of 830 nm (beam diameter 3 μm, emission power 10 mW). Tested. When pulses were transmitted at a scanning speed of 40 c/sec, pits were formed and the C/N ratio and error rate were measured for each example. The results are shown in Table 6.

Further, Table 6 also shows the minimum power required to form pits when recording was performed by changing only the laser emission power among the above recording conditions.

Further, an acceleration test was conducted under the condition of constant temperature of 40° C. 190% and irradiation of 20.0001 uX with a halogen lamp.

The results are also shown in Table 6.

Comparative example 7 Experiments were conducted in exactly the same manner as in Examples 19-24.

However, no light absorber was added. The results are shown in Table 6.

Example 1 24, the present invention is effective. I understand.

(Effects of the Invention) According to the present invention, it is possible to provide a flexible digital recording material that can be laser recorded and has good recording and reproducing characteristics.

Claims (1)

[Scope of Claims] 1) Directly below the metallic silver-containing layer formed by the reaction of a silver compound in the presence of silver or metal development nuclei nobler than silver, the layer has substantial absorbance in the wavelength range of a semiconductor laser. Optical recording material in which a layer containing a light absorber is present. (2) An optical recording material according to claim (1), which contains photosensitive silver halide microcrystals and can be preformatted by pattern exposure. (3) The optical system according to any one of claims (1) and (2), by heating the silver compound and a metal development nucleus containing silver or a metal nobler than silver to a temperature of at least 70°C or higher. A manufacturing method for manufacturing recording materials. (4) A recording method for recording information by causing a change in reflectance by irradiating the optical recording material according to any one of claims (1) and (2) with pulsed laser light.