JPH07108784A - Production of cover paper - Google Patents

Abstract

PURPOSE:To obtain cover paper that can be recycled and easily produced with a high glossiness and a superior wear resistance by a method wherein printing with photosetting ink and printing with photosetting varnish are continuously made on base paper having specific glossiness and smoothness using a multicolor printing press. CONSTITUTION:In cover paper of a text book or the like, printing with photosetting ink and printing with photosetting varnish are continuously made on base paper having a glossiness of 65% or more by JIS P 8142 and a smoothness of 2000sec or more by J.TAPPI No.5 (a paper pulp test method using an air micrometer tester) using a multicolor printing press. As the photosetting ink and the photosetting varnish, any material curing by the irradiation of an ultraviolet radiation (UV) or an electron beam(EB) can be used without esp. limiting the composition or the like thereof, and a radical photopolymerizable monomer or oligomer containing vinyl or a ring opening photopolymerizable compound containing epoxy can be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a cover sheet for a textbook or the like, and more specifically, a cover sheet which is recyclable, has a high gloss, is excellent in abrasion resistance, and can be produced extremely easily. The present invention relates to a paper manufacturing method.

[0002]

2. Description of the Related Art A cover sheet for a textbook or the like must be glossy and highly durable. Conventionally, most of the cover sheets are produced by printing a base sheet and then pasting or laminating a film.

[0003]

However, in the above-mentioned conventional method, since the film has to be attached or laminated in another step after the step of printing the base paper, the work is troublesome. . Further, since it has to be dried after printing, it takes time. Furthermore, the resulting cover sheet was not recyclable.

On the other hand, after the step of printing on the base paper, a UV-curable varnish is coated, and a drum-shaped or film-shaped support having a high smoothness (having a mirror surface) (hereinafter referred to as a mirror surface support). ) Is adhered, and in this state, ultraviolet rays are irradiated to cure the ultraviolet curable varnish, and then the specular support is peeled off. The cover sheet produced by this method has an advantage that it can be recycled because no film is used. However, this method cannot reduce the number of steps as compared with the above method, but rather increases the steps for attaching and detaching the mirror surface support. Further, a translucent mirror surface support must be used to irradiate ultraviolet rays in a state where the base paper and the mirror surface support are laminated, but since such equipment is expensive, its practical value is low. It was a thing.

[0005]

The present invention has been proposed in view of the above, and has a glossiness of 65 according to JIS P 8142.
% Or more, TAPPI No. Printing with a photocurable ink and a photocurable varnish on a base paper with a smoothness of 2000 seconds or more according to 5 (paper pulp test method using an air micrometer type tester, established in July 1966) using a multicolor printing machine. The present invention relates to a method of manufacturing a cover sheet, which is characterized in that the printing by the method is continuously performed.

The base paper used in the present invention is JIS P
8142 has a gloss of 65% or more, and TAPPI
No. If the smoothness according to No. 5 is 2000 seconds or more, the grammage, the material, etc. are not limited, and any material can be used. If the glossiness or smoothness is lower than the above range, high glossiness cannot be obtained even if the photocurable ink and the photocurable varnish are printed on the surface.

The photocurable ink used in the present invention,
Photocurable varnish is ultraviolet (UV) or electron beam (EB)
The composition is not particularly limited as long as it can be cured by irradiation with, and it may be a photoradical polymerization type of a monomer or oligomer containing a vinyl group or a photoring-opening polymerization type of a compound containing an epoxy group. good. Therefore, a photopolymerization initiator (only in the case of ultraviolet irradiation), a monomer, an oligomer and the like may be appropriately selected, and various additives and pigments (only in the case of ink) may be added as necessary. For example, acrylic oligomers are most often used as oligomers, especially when urethane acrylate is used, the abrasion resistance tends to be improved, and when a leveling agent or a viscosity reducing agent that lowers the surface tension is used as an additive, the glossiness is increased. However, the present invention is not limited to this.
The printing thickness of the photocurable ink and the photocurable varnish is not particularly limited, and the photocurable ink may be partially printed.

Further, the multicolor printing machine used in the present invention is also
The structure is not particularly limited as long as it has an ultraviolet irradiation mechanism or an electron beam irradiation mechanism as a drying mechanism. For example, the printing format is not limited to any one such as an offset method and a screen method.

Further, the present invention is a treatment by a general-purpose method using the above-mentioned extremely general-purpose materials and equipment, and can be processed extremely easily. Further, the produced cover sheet has high glossiness without using a conventional mirror surface support. further,
Since the cured product of the ultraviolet curable varnish is three-dimensionally crosslinked, it has excellent wear resistance.

[0010]

EXAMPLES Examples of the present invention will be shown below.

Example 1; basis weight 190 g / m ² , JIS
Glossiness according to P 8142 79.2%, J.P. TAPPI
No. UV-curable ink (manufactured by Dainippon Ink and Chemicals, Inc., trade name: New DICURE Z Process Beni A-11N ”) is partially printed (printing thickness: about 0.5 μm), and on top of that, a UV curable varnish (Dainippon Ink and Chemicals Co., Ltd., trade name“ New ” DICURE Z OP varnish HG ”) was printed (printing thickness: about 0.8 μm), and was irradiated with ultraviolet rays to be cured to prepare a cover sheet of Example 1 of the present invention.

Performance Test 1, Glossiness; JIS P 814
The glossiness was measured according to 2, and the results are shown in Table 1.

Performance test 2, Eraser resistance; Eraser made by Tombow Pencil Co., Ltd. (trade name "Monolite") was used to strengthen the printing surface with a width of about 12 mm and a length of about 20 mm.
The degree of rubbing and ink removal was observed with the naked eye, those with almost no change were judged to be “good”, and those with confirmed ink removal were judged to be “poor”, and the results are shown in Table 1.

Performance test 3, recyclability; JIS P
An 8209 standard disintegrator was used to disintegrate 25 at a concentration of 1.2%, and those disaggregated were judged to be "good" and those not disaggregated were judged to be "poor". The results are shown in Table 1.

Comparative Example 1; basis weight 190 g / m ² , JIS
Gloss degree according to P 8142 53.0%, J.P. TAPPI
No. A cover sheet of Comparative Example 1 was prepared in the same manner as in Example 1 except that a base paper (Ivory cardboard manufactured by Nippon Paper Industries Co., Ltd.) having a smoothness of 1680 seconds according to No. 5 was used. This cover sheet of Comparative Example 1 was subjected to the same performance tests 1 to 1 as in Example 1 above.
Evaluation was made according to No. 3, and the results are shown in Table 1.

Comparative Example 2; Oil-based ink (manufactured by Dainippon Ink and Chemicals, Inc., trade name "Carton Self Process"
A cover sheet of Comparative Example 2 was prepared in the same manner as in Example 1 except that a red varnish ”) and an oil varnish (trade name“ Carton Self GW Varnish ”manufactured by Dainippon Ink and Chemicals, Inc.) were used. The cover sheet of Comparative Example 2 was evaluated by performance tests 1 to 3 in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 3 A comparative example is a resin processed product in which an oil-based ink (manufactured by Dainippon Ink and Chemicals, Inc., trade name "Carton Self Process Beni N") is printed on the surface and a film is stuck on the surface. The cover sheet of No. 3 was used. This cover sheet of Comparative Example 3 was subjected to the same performance tests 1 to 3 as in Example 1 above.
Evaluation was made according to No. 3, and the results are shown in Table 1.

[0018]

[Table 1]

The "UV ink" in the ink column of Table 1 indicates an ultraviolet curable ink, and the "UV varnish" in the varnish column indicates an ultraviolet curable varnish. Further, in the glossiness column of Table 1, the “blank paper part” is a portion where the varnish is directly printed on the base paper (Example 1 and Comparative Examples 1 and 2) or the film is directly attached on the base paper. The "printed portion" indicates the glossiness in the exposed portion (Comparative Example 3), and the "printed portion" is a portion in which the ink is printed on the base paper and the varnish is further printed thereon (Example 1 and Comparative Examples 1 and 2). Alternatively, it shows the glossiness of a portion (Comparative Example 3) in which the ink is printed on the base paper and the film is further stuck thereon.

As is clear from Table 1, the cover sheet of Example 1 has high glossiness and wear resistance (eraser resistance).
The recyclability was also good. On the other hand, in Comparative Example 1 in which the glossiness and smoothness of the base paper were low, the glossiness was particularly low in the blank printed area. Further, it was confirmed that Comparative Example 2 using the oil-based ink and the oil-based varnish had low gloss and abrasion resistance, and Comparative Example 3 having the film adhered thereto could not be recycled.

Although the embodiments of the present invention have been described above, the present invention can be implemented in any manner without changing the scope of the claims.

[0022]

As described above, according to the method of manufacturing the cover sheet of the present invention, since the photocurable ink and the photocurable varnish are continuously printed by the multicolor printing machine, the processing is substantially performed in one step. And the cover sheet can be easily manufactured in a short time. Further, the present invention has high practical value because it does not use any special equipment (transparent mirror surface support) unlike the above-mentioned conventional method. Further, the cover sheet produced is not a laminate of films and thus can be recycled, and it has high gloss and is beautiful and has excellent abrasion resistance. The printed part is not damaged and can be used while maintaining its beautiful condition.

Claims (1)

[Claims] 1. A base paper having a glossiness of 65% or more and a smoothness of 2000 seconds or more is continuously printed with a photocurable ink and a photocurable varnish using a multicolor printer. A method for manufacturing a cover sheet, comprising: