JPH0519474B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a laser recording film using a heat mode recording method, and particularly to a laser recording film that has excellent performance as a plate-making film. In recent years, many methods using laser light have been proposed in fields where high-speed or real-time recording of information is required. This method utilizes the strength and resolution of the optical energy of laser light, and the laser light is irradiated onto a substance with good light absorption, and the heated material that absorbs the light is deposited on the image receiving surface. It records images. [Prior Art and Problems] Regarding such recording films, the present inventors have also achieved high blackening density by using a non-self-oxidizing binder as a binder and further using graphite as heat-absorbing fine particles. Furthermore, by incorporating a heat ray absorber that has strong absorption ability in the wavelength range of the YAG laser beam used for recording, it is possible to easily transfer the recording medium to the transfer image receiving surface of paper, printing plate, etc. Patent Application No. 59-41724 discloses that it is possible to obtain a laser recording film that can produce high-resolution negative and positive images without leaving any residue of the recording medium on the transparent substrate. I applied.
However, such a recording layer itself is easily scratched, and since the dry coating film thickness is as thin as about 0.5 μm, scratches easily reach not only the surface of the recording layer but also the surface of the substrate. Such scratches significantly impair the function of the film for laser recording. As a method to solve this problem, the present inventors have found that by providing a protective layer made of a thermoplastic polymer on the recording layer, a laser recording film with remarkable scratch resistance compared to conventional laser recording films can be obtained. Found out the patent application 112311, 1984.
No. 59-185176. However, in all of these cases, a heat ray absorber is added to the recording layer, and since the recording layer coating liquid is a dispersion of fine particles with high light shielding and heat absorbing properties, the type and amount of the heat ray absorber added may vary. In the past, there were problems with sedimentation and aggregation of fine particles. If the fine particles in the recording layer coating solution settle or aggregate, the blackening density will decrease after coating, resulting in poor light-shielding properties as a negative film (manuscript film for plate making), and thin printing even as a positive image on the transfer side. becomes. [Means for Solving the Problems] As a result of intensive studies to solve these problems, the present inventors have added thermoplastic polymers to the surface of the recording layer on the transparent support and laser beams used for recording. By providing a protective layer made of a heat ray absorber that has a strong absorption ability in the wavelength region, it is possible to obtain a laser recording film that has the same transferability even when it is transferred under the same conditions as a conventional laser recording film. The present invention was achieved by discovering that That is, the present invention provides a laser recording film in which a recording layer containing a non-self-oxidizing binder and fine particles imparting high light-shielding properties and absorbing heat is provided on a transparent support. The present invention provides a film for laser recording characterized in that it is provided with a protective layer made of a thermoplastic polymer and a heat ray absorber having a strong absorption ability in the wavelength range of laser light used for recording. As shown in FIG. 2, the method of recording on the laser recording film of the present invention involves scanning and guiding a laser beam adjusted through a normal lens system and adjustment device from the side of the transparent support 1 to coat the recording medium. A method can be used in which the layer (transfer supply body) 2 is deposited on the image receiving surface of the transfer image receptor 4 to record an image. It is desirable that the transfer image receiver 4 be mounted in contact with the transfer supply member 2, and resolution can be improved by improving the degree of adhesion by reducing the pressure. According to this method, the transfer image receptor 4 can be transferred in one operation.
A positive image can be obtained on the top and a negative image can be obtained on the transfer supply body 2. The negative film can be used as an original film when producing a printing resin plate, and the positive image can be used as a proof copy or a direct printing plate depending on the type of transfer image receptor 4. The transparent support for the laser recording film of the present invention, especially the laser platemaking film, may be any film that transmits laser light well, such as polyethylene terephthalate, polyvinyl chloride, polyvinylidene chloride, polystyrene, polypropylene, polycarbonate, nylon, etc. 6. Films such as pothiether sulfone can be mentioned. In particular, biaxially stretched films such as polyethylene terephthalate and polypropylene are preferred because they have excellent transparency, strength, dimensions, and stability. Fine particles that absorb heat in the recording medium and particles that provide high light-shielding properties include graphite and the like.
This graphite can be used alone or in a mixture with carbon black or the like. This graphite is used in order to provide a high blackening density in a thin film.
Generally, fine particles with a size of 2μ or less are preferable. More preferably, graphite having a particle size distribution in which 50% or more of the particles are 0.4μ or less and 25% or more are 0.2μ or less is suitable. Non-self-oxidizing binders in the recording medium include acrylic resins, cellulose derivatives other than nitrocellulose, phenolic resins, polyvinyl chloride,
Vinyl chloride-vinyl acetate copolymer and the like can be used. By using a non-self-oxidizing binder in the recording layer, there are no concerns about the safety of self-oxidizing binders such as nitrocellulose during storage, and there are no problems with equipment corrosion due to acidic substances generated during laser light irradiation. . The blackening density of the recording medium is determined to provide light-shielding properties.
It is 0.5 or more, preferably 2.0 or more. If the blackening density is low, the negative film (manuscript film for plate making)
The light-shielding performance is poor, and even positive images result in faint prints. Therefore, the amount of non-autooxidizing binder is 20 to 100 parts by weight per 100 parts by weight of graphite.
It is preferably used in an amount of 50 parts by weight or less. The thickness of the recording medium layer and the protective layer are affected by the output of the laser beam used and the amount of heat ray absorber added, but the total thickness of the recording medium layer and the protective layer is 0.1~
A good range is 0.7μ, preferably 0.2 to 0.5μ.
If the protective layer is applied to a thickness sufficient to prevent damage to the recording medium layer, for example 1.0 μm or more, the recording sensitivity to laser light will be significantly reduced. The added amount of the heat ray absorber, which is a feature of the present invention and is contained in the protective layer and has a strong absorption ability in the wavelength range of the laser light used for recording, is preferably in the range of 0.01 to 200 parts by weight, particularly 0.1 to 100 parts by weight. . Examples of this heat ray absorbent include compounds represented by the following general formulas. General formula; (Here, R is hydrogen or a lower alkyl group, X is an anion selected from the group consisting of hexafluoroarsenate ion, hexafluoroantimonate ion, fluoroborate ion, and perchlorate ion, and m is 0 or an integer of 1 or 2.A is

[expression] or

[Formula] is shown, n is an integer of 1 or 2, and when m is 2, A is

〔Effect of the invention〕

The laser recording film of the present invention is a real-time recording that does not require post-processing such as development and fixing, and is not exposed to light, so darkroom operations are not required, and it can be used for communication and computer processing information, which are rapidly developing in recent years. It is ideal for direct recording, and has excellent scratch resistance and resolution, so it can be widely applied. [Example] Hereinafter, the present invention will be explained with reference to Examples. Example 1 A graphite dispersion having the following formulation 1 was coated on a 100 μm polyester film by bar coating and dried at 90° C. to form a recording layer.
A liquid mixture consisting of Formulation 2 was applied onto this recording layer by dip coating and dried at 90°C to form a protective layer. Dry film thickness, blackening density, scratch resistance test results and Nd-YAG laser (wavelength 1061nm,
Table 1 summarizes the results of the image forming test using irradiation with an output of 10 W and 0.5 Joule/cm ² ) on the recording medium. Formulation 1 Graphite 100 parts Ethyl cellulose 36 parts Ethyl acetate 1224 parts Formulation 2 Solvent-soluble polyester resin (Toyobo Co., Ltd. "Vylon 200") 100 parts Bis(p-diethylaminophenyl) [N, N-
Bis-(p-diethylaminophenyl) aminium hexafluoroantimonate 5 parts Methyl ethyl ketone 945 parts Example 2 A coating solution consisting of Formulation 3 was applied by dip coating onto the recording layer coated in Example 1, and 90
It was dried at ℃ to form a protective layer. Dry film thickness, blackening density, scratch resistance test results and Nd−
Table 1 summarizes the results of an image forming test using YAG laser (wavelength 1064 nm, output 10 W, 0.5 Joule/cm ² on the recording medium) irradiation. Formulation 3 Ethylene-vinyl acetate copolymer (Mitsui Polychemical Co., Ltd. "220") 100 parts N,N,N',N'-tetrakis(dibutylaminophenyl)-p-benzoquinone-bisimmonium hexafluoroantimonic acid 945 parts of salt Example 3 A coating solution consisting of Formulation 4 was applied by dip coating onto the recording layer coated in Example 1,
It was dried at 150°C to form a protective layer. Dry film thickness, blackening concentration, scratch resistance test results, and Nd−
Table 1 summarizes the results of an image forming test using YAG laser (wavelength 1064 nm, output 10 W, 0.5 Joule/cm ² on the recording medium) irradiation. Formulation 4 Polyamide resin (“AQ Nylon A-70” manufactured by Toray Industries, Inc.) 100 parts Bis(1-mercapto-2-naflate)nickel()tetra-n-butylammonium (PA-1001” manufactured by Hodogaya Chemical Co., Ltd.) 5 parts Dimethylformamide 945 parts Comparative Example 1 A film coated with only Formulation 1 in Example 1 was used as a comparative example.

[Table] Note *2 The scratch resistance test of the examples was conducted according to the following method.
As shown in FIG. 3, a film consisting of a support 1, a recording layer 2, and a protective layer 3 is cut into 10 cm x 10 cm pieces, a piece of paper 5 with an area of 1 cm ² is placed on the coated surface, and while a load 6 is applied, it is horizontally Move it 5cm. After that, check whether there are any scratches on the moved part. An experiment was conducted while applying a load, and the value of the load when the recording layer was scratched was evaluated as the scratch resistance of the protective layer using the following criteria. Here, the evaluation is in three stages: A, B, and C.
A, B, and C are A: The recording layer is not scratched under a load of 500 g. B: No damage to the recording layer under a load of 250g. C: Scratches occur under a load of 50g. means.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a laser recording film of the present invention, FIG. 2 is a schematic cross-sectional view of a recording device using the film of the present invention, and FIG. 3 is a diagram showing a measuring method for a scratch resistance test. . 1... Support, 2... Recording layer, 3... Protective layer,
4... Transfer image receptor, 5... Paper, 6... Load.

Claims (1)

[Claims] 1. In a laser recording film in which a recording layer containing a non-self-oxidizing binder and fine particulate graphite is provided on a transparent support, a thermoplastic polymer and a thermoplastic polymer used for recording are disposed on the recording layer. 1. A laser recording film comprising a protective layer comprising a heat ray absorber having a strong absorption ability in the wavelength region of laser light.