Claims
- 1. A duplicate thermoplastic printing plate bearing a printing relief pattern theron, said printing plate comprising a sheet having a thickness of 1.0 to 10 mm, said sheet comprising syndiotactic 1,2-polybutadiene having a crystallinity of approximately 10 to 30% and an intrinsic viscosity of greater than approximately 0.7 when measured in toluene at 30.degree. C.
- 2. The duplicate thermoplastic printing plate according to claim 1 wherein said syndiotactic 1,2-polybutadiene has an intrinsic viscosity of from about 1.0 to 2.5 when measured in toluene at 30.degree. C.
- 3. The duplicate thermoplastic printing plate according to claim 1 including an admixture of a thermoplastic resin with said syndiotactic 1,2-polybutadiene.
- 4. The duplicate thermoplastic plate according to claim 3, wherein said thermoplastic resin used in admixture with the syndiotactic 1,2-polybutadiene is a member selected from the group consisting of a homopolymer or copolymer of ethylene or propylene, polycarbonates, ABS resins and polyvinyl chloride and has a melt index of from about 3 to 400 and is used in amount of from about 1 to 500 parts by weight with respect to 100 parts by weight of said syndiotactic 1,2-polybutadiene.
- 5. A crosslinked matrix suitable for the manufacture of a duplicate thermoplastic printing plate, said plastic matrix having a thickness of 1 to 10 mm and comprising syndiotactic 1,2-polybutadiene having a crystallinity of approximately 10 to 30% and an intrinsic viscosity of greater than approximately 0.7 when measured in toluene at 30.degree. C; and a curing catalyst dispersed in said syndiotactic 1,2-polybutadiene.
- 6. The plastic matrix according to claim 5, wherein said catalyst is a member selected from the group consisting of a photoinitiator and a thermally curable substance.
- 7. The plastic matrix according to claim 6, wherein the photoinitiator is a member selected from the group consisting of 5-nitroacenaphthene, anthracene, p-dinitrobenzene, m-dinitrobenzene, 2-chloro-4-nitroaniline, 9-anthranyl aldehyde, benzophenone, benzil, p,p'-tetramethyl diaminobenzophenone, benzanthrone, 1,2-benzanthraquinone, 1,2-naphthoquinone, 1,4-naphthoquinone, benzoin, benzoin methyl ether, benzoin isopropyl ether and benzoin n-butyl ether.
- 8. The plastic matrix according to claim 6, wherein said thermally curable substance is a member selected from the group consisting of dicumyl peroxide, 2,5-dimethyl-2,5-di-tert-butyl peroxyhexane, 2,5-dimethyl-2,5-di-tert-butyl peroxyhexene-3, di-tert-butyl hydroperoxide and cumenyl hydroperoxide.
- 9. The plastic matrix according to claim 5, wherein said catalyst is used in an amount of from about 0.01 to 10 parts by weight per 100 parts by weight of said syndiotactic 1,2-polybutadiene.
- 10. The plastic matrix according to claim 9, wherein said catalyst is used in an amount of from about 0.05 to 5.0 parts by weight per 100 parts by weight of said syndiotactic 1,2-polybutadiene.
- 11. A modified paper matrix suitable for the manufacture of a duplicate thermoplastic printing plate, comprising a paper substrate and bonded to said substrate a layer of crosslinked syndiotactic 1,2-polybutadiene having a crystallinity of approximtely 10 to 30% and an intrinsic viscosity of greater than approximately 0.7 when measured in toluene at 30.degree. C, said layer having a thickness of from about 0.01 to 0.1 mm.
Priority Claims (1)
| Number |
Date |
Country |
Kind |
| 48-39941 |
Apr 1973 |
JP |
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Parent Case Info
This application is a continuation-in-part application of our copending application Ser. No. 458,855 filed Apr. 8, 1974 now abandoned and entitled "Thermoplastic Duplication Plates And Process For Manufacture Thereof."
The present invention relates to duplicate thermoplastic plates and a method of manufacturing the duplicate thermoplastic plates. More particularly, the present invention relates to duplicate thermoplastic plates and a method of molding the plates against a thermoplastic matrix which is formed against an original relief pattern. This invention also includes a method of forming a thermoplastic matrix for use in manufacturing the duplicate plates and materials to be used therefor.
The method in accordance with the present invention lends itself particularly to the duplication of thermoplastic duplicate plates and matrix against an original pattern in large amounts, which may find use in printing and for decorative purposes as interior and outer building materials or displays and in various fields in which relief pattern may be employed.
In a field where a great number of copies of publication such as newspapers and magazines should be printed within a given short period of time, a number of printing plates are needed. Conventional methods of molding plural printing plates from an original plate involve transcription of relief pattern on duplicate printing plates by bringing moldable resinous materials in melt or soft state into contact with a metallic roll or flat metallic plate on the surface of which the relief pattern is formed. The relief pattern is generally formed by manual work such as chemical engraving. The manual work requires skilled workers for engraving the relief pattern. This involves quite a lot of labor and cost. The chemical engraving requires the employment of etching solutions which should face problems with pollution and working conditions. In these respects, conventional methods are not appropriate for this purpose. Accordingly, a simplified method capable of the duplication of plates from an original plate without the disadvantages of the conventional methods has long been demanded.
In a field where a high reproducibility is required such as in flexography, materials for flexographic plates are generally composed of a phenolic formaldehyde resin. The resin can work as the flexographic plate only after being thermally cured. The temperature at which said resin cures is so high that a photosensitive polymeric plate used as an original pattern from which the flexographic plates are formed may be deformed upon the application of such high temperatures over the flexographic plate superposed on the original pattern. This will impair its reproducibility of relief image on the original pattern sometimes to such an extent that the image cannot be reproduced. The flexographic plates prepared by such conventional materials are usually disposed by burning, but this may cause a problem because of the generation of a noxious gas. It has accordingly been demanded that a material for flexographic plates is provided which can reduce to a considerable extent or is substantially free from the disadvantages of conventional materials useful therefor.
In order to avoid the difficulties of conventional methods, the use of thermoplastic resins has been attempted. For example, U.S. Pat. No. 3,408,437 to Wheeler III et al. discloses thermoplastic printing plates by forming a thermoplastic matrix against an original pattern from a thermoplastic material having a heat distortion temperature at 264 p.s.i. of at least about 65.degree. C. Wheeler III et al. use materials including polyarylene polyethers, polypropylene, acrylonitrile-butadiene-styrene (ABS) copolymers, polyhydroxyethers, impact polystyrene, styrene-acrylonitrile copolymers, polycarbonates, poly-4-methyl pentene-1, and the like. The use of these materials as matrix materials, however, requires high temperatures and pressures and long period of time for molding the matrix. Accordingly, improvements in these respects have been desired.
It is therefore an object of the present invention to provide duplicate thermoplastic plates which is molded against a matrix composed of materials capable of being molded at a relatively low temperature and pressure.
Another object of the present invention is to provide a method of the manufacture of the duplicate thermoplastic plates having properties as stated above.
A further object of the present invention is to provide a method of the manufacture of the duplicate thermoplastic plates by simplified procedures and with ease.
A still further object of the present invention is to provide a thermoplastic matrix material from which the matrix is formed against an original relief pattern. Another embodiment of the present invention is a method of molding the thermoplastic matrix against which the duplicate thermoplastic plates are molded.
A still further object of the present invention is to provide a material useful for flexographic plates which can reproduce a pattern with high precision.
US Referenced Citations (11)
Continuation in Parts (1)
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Number |
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| Parent |
458855 |
Apr 1974 |
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Patent Grant
4103057
