JP3278599B2 - Printing method of flexible vinyl chloride film / sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for printing a flexible vinyl chloride film / sheet, and more particularly to a method for printing a flexible vinyl chloride film / sheet using a letterpress rotary printing machine.

[0002]

2. Description of the Related Art Conventionally, on the front and back surfaces of a soft vinyl chloride film / sheet, when the films / sheets are stacked after printing, the so-called blocking in which the films / sheets are adhered to each other is prevented, and the processing appropriateness after printing is improved. For this purpose, for example, a slip agent such as starch powder has been provided. Also,
Conventionally, soft vinyl chloride films / sheets are often formed by a gravure printing method, but the gravure printing ink is a solution type ink, and the gravure printing ink is dried by passing the printed matter through a hot air dryer. It was fixed on the surface of a soft vinyl chloride film / sheet.

[0003]

However, when the slip agent is applied, it is difficult for the printing ink to be fixed on the surface of the soft vinyl chloride film / sheet, which causes a poor transfer of the printing ink. Further, in the gravure printing method, the plate making unit price is very expensive, so that there is a disadvantage that the product unit price increases in small lot printing. In addition, the drying process using a hot air dryer has disadvantages such as an increase in equipment size and the necessity of equipment for removing the solvent. Had the disadvantage of becoming huge.

[0004] Therefore, a main object of the present invention is to print a flexible polyvinyl chloride film / sheet which is less likely to cause printing ink transfer failure during printing, suitable for small lot printing, and can be efficiently printed with relatively small-scale equipment. Is to provide a way.

[0005]

SUMMARY OF THE INVENTION According to the present invention, there is provided a step of preparing a soft vinyl chloride film / sheet in a roll state without applying a slip material, and drawing the soft vinyl chloride film / sheet from the roll. Continuously printing, printing on soft vinyl chloride film / sheet with ultraviolet curable ink using letterpress using a letterpress rotary printing machine, and irradiating ultraviolet rays while cooling the soft vinyl chloride film / sheet. A method for printing a soft vinyl chloride film / sheet, comprising the steps of: In the method for printing a flexible vinyl chloride film / sheet according to the present invention,
While continuously transferring the soft vinyl chloride film / sheet, printing is performed with a UV-curable ink using a relief printing plate (photosensitive resin) using a relief printing press, and then wound into a roll. Therefore, in a further processing step, if the roll is rewound again, the film / sheet can be pulled out, so that there is no need to use a slip agent. for that reason,
No transfer failure of the printing ink caused by the slip agent occurs. In addition, the use of a photosensitive resin relief printing plate makes the cost of plate making less expensive than gravure printing and the like, and also cures and fixes the UV-curable ink by UV irradiation, so that small lot printing can be performed at low cost. it can. Furthermore, while flexible vinyl chloride films / sheets are susceptible to heat, the present invention provides for flexible vinyl chloride films / sheets.
Since the ultraviolet irradiation is performed while cooling the sheet, deformation of the flexible vinyl chloride film / sheet due to heat generated at the time of ultraviolet irradiation is prevented.

In the method for printing a flexible vinyl chloride film / sheet according to the present invention,
It is preferably formed of a nylon-based photosensitive resin. Nylon photosensitive resin relief printing plates have excellent resolution and reproducibility, and are also excellent in plate thickness accuracy and printing durability. According to the nylon photosensitive resin relief printing plate, a clear image can be obtained on the surface of the soft vinyl chloride film / sheet. In addition, the cost of plate making is lower than that of the gravure printing method.

Further, the method for printing a flexible vinyl chloride film / sheet according to the present invention preferably includes a step of performing a corona discharge treatment on the surface of the flexible vinyl chloride film / sheet before the printing step. In this case, the printability of the surface of the soft vinyl chloride film / sheet is improved, and the fixing property of the ultraviolet curable ink is further improved.

Further, the method for printing a flexible vinyl chloride film / sheet according to the present invention preferably includes a step of removing the charge of the flexible vinyl chloride film / sheet. The soft vinyl chloride film / sheet is easily charged, but when charged, dust is easily adsorbed on the surface of the soft vinyl chloride film / sheet, in which case it is adsorbed on the surface of the soft vinyl chloride film / sheet. The generated dust prevents fixing of the ultraviolet-curable ink and causes printing failure. Also, the charged soft vinyl chloride film / sheet may discharge, for example, to an operator, in which case workability is hindered. Therefore, in the present invention, these disadvantages can be prevented by providing a step of removing the electrification of the soft vinyl chloride film / sheet.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0010]

FIG. 1 is an illustrative view showing one example of a letterpress rotary printing apparatus used in the present invention. First, the letterpress rotary printing apparatus 10 will be described.

The letterpress rotary printing apparatus 10 includes printing apparatus units 16a, 16b, 16c, 16d, 16e, 16e of six colors along an outer peripheral surface of an impression cylinder 14 provided on a chassis 12.
f, and a printing device unit 16g for the seventh color is provided at a position slightly apart from the impression cylinder 14.

Each printing device unit 16a to 16g
Are plate cylinders 18a, 18b, 18c, 18d, 1
8e, 18f and 18g, and the plate cylinders 18a to 18a
8 g of the printing production unit 16 so as to contact the impression cylinder 14.
a to 16 g.

Further, the printing device units 16a to 16
g is provided with an ink storage device (not shown) for storing the ink, and transfers the ultraviolet curable ink stored in the ink storage device to the plate cylinders 18a to 18f by transferring them to rollers interposed therebetween. It is configured.

Further, each of the printing device units 16a to 16a
Downstream of 6 g, cold mirror type ultraviolet irradiation devices 20 a, 20 b, 20 c, and 20 equipped with an ultraviolet lamp are provided.
d, 20e, 20f, 20g and 20h are provided,
Each of the printing device units 16a to 16g is formed so as to cure the ultraviolet curable ink transferred and printed on the vinyl chloride film A as a printing object. In addition,
The impression cylinder 14 is formed so as to be able to cure the ultraviolet-curable ink while cooling so that it does not shrink when the ultraviolet-ray irradiators 20a to 20f irradiate the vinyl chloride film A as the printing material with ultraviolet rays. .

The plate cylinder 18g of the printing unit 16g, which does not contact the impression cylinder 14, comes into contact with an impression cylinder 22 provided separately from the impression cylinder 14 and downstream of the transfer of the printing material. And
The ultraviolet irradiators 20g and 20h provided downstream from the printing device unit 16g are shrunk when the polyvinyl chloride film A as a printing material is heated by the ultraviolet irradiation, and thus are provided close to the cooling roll 24, A is formed so that A is irradiated while cooling.

Next, a method of printing a soft vinyl chloride film / sheet by the letterpress rotary printing apparatus 10 shown in FIG. 1 will be described. In addition, in this specification, a soft vinyl chloride film / sheet means both a soft vinyl chloride film and a soft vinyl chloride sheet. The soft vinyl chloride film and the soft vinyl chloride sheet to which the present invention is applied are simply different in name due to difference in thickness, and are essentially the same. Soft vinyl chloride films / sheets have good transparency and can impart various properties depending on the type and amount of the plasticizer contained, and on the processing method and processing conditions. For example, generally, when the amount of the plasticizer is increased, elongation is improved, and tear strength and low-temperature resistance are improved. In the following description,
The soft vinyl chloride film A will be described for the sake of simplicity, but it goes without saying that the same applies to a soft vinyl chloride sheet. Incidentally, on the surface of the vinyl chloride film A as a printing material, starch powder as a slip material generally used does not adhere at all,
Even if this starch powder is not applied, since it is wound in a roll shape, if it is unwound from the roll state, printing can be performed, and after printing, it can be wound into a roll state,
When used, it can be used by unwinding from the roll state, so that starch is not necessary.Because such starch is not attached, poor transfer of printing ink can be prevented, and extremely beautiful printing can be achieved. Can be applied.

In the letterpress rotary printing apparatus 10, a vinyl chloride film A to be printed is wound in a roll shape and loaded on a supply reel 26, and the vinyl chloride film A pulled out from the roll is converted into a vinyl chloride film as a printing material. The print surface of the film 9 reaches a corona processing device 28 for performing corona processing. The corona treatment device 28 performs a high-voltage corona discharge on the printing surface of the soft vinyl chloride film in order to increase the adhesion of the ultraviolet curable ink. Although this corona discharge treatment may be performed off-line, it is more efficient to incorporate the corona discharge device into a printing device and perform in-line processing in which the treatment is performed simultaneously with the printing operation. By performing the corona discharge treatment, the printability of the surface of the soft vinyl chloride film is improved, and the fixing property of the ultraviolet curable ink is further improved.

Further, the vinyl chloride film A is printed on the edge of the edge guide 30 provided downstream thereof in a state where the printing apparatus is excellently printed due to the action of a sensor or the like for transporting the vinyl chloride film A straight. The position is controlled so that it can be sent to 16a to 16f. The vinyl chloride film A reaches the impression cylinder 14 through the edge guide 30.

The vinyl chloride film A which has reached the impression cylinder 14
After the appropriate printing is performed in the printing unit 16a to 16f, the printing finally reaches the printing unit 16g to print the seventh color. In the meantime, the vinyl chloride film A, which is a printed material printed with the ultraviolet curable ink in each of the printing device units 16a to 16f, passes through the ultraviolet irradiation devices 20a to 20f, where the ink is cured, and further the seventh printing device unit 16
g.

In this embodiment, an ultraviolet curable ink is used as the printing ink. Particularly, the UV-curable ink contains, for example, 5 to 30% of a pigment, 5 to 50% of a photosensitive resin, 15 to 65% of a photosensitive monomer, 5 to 20% of a photopolymerization initiator, and 10% or less of an auxiliary agent. Use things.

The final 7th color printing unit 16g
In the above, the vinyl chloride film A printed with the ultraviolet curable ink reaches the cooling roll 24, and when passing around the cooling roll 24, the ultraviolet irradiation device 20g
And 20h are configured to cure the previously printed ultraviolet curable ink entirely more completely.

The soft vinyl chloride film is very easily charged, and when charged, easily adsorbs dust, and gives a worker an unpleasant sensation to hinder workability. Since there is an inconvenience, the static elimination brush 32
To the take-up reel 34.
As described above, the soft vinyl chloride film is very easily charged, and when charged, it is easy to adsorb dust.
The static electricity is removed by appropriately performing a static elimination treatment with a static elimination brush or a static elimination device.

In the letterpress rotary printing apparatus 10, the vinyl chloride film A wound into a roll is supplied to the supply reel 2.
When the vinyl chloride film A is transported from the printer 6 to the printing device units 16a to 16g, the in-feed roll 36 and the out-feed roll 38 are accurately drawn out of the roll state and transported. No problem at all. Further, the vinyl chloride film A is easily stretched, but when the transfer of the vinyl chloride is performed, for example, when the sag or the like occurs at the printing device units 16a to 16f, the printing cannot be performed clearly. By rotating the outfeed roll 38, tension is applied to the vinyl chloride film A.

The printing in the printing unit 16a to 16g can be performed on both the front and back surfaces of the vinyl chloride resin sheet. For example, when printing on the front surface, the printing is performed on the front surface of the lowermost vinyl chloride resin sheet. First, a printing layer is formed with white ink, and when printing on the back surface, if the uppermost layer, which is the final layer, is solid-printed with white ink, the color printing formed on the vinyl chloride film A can be shined. it can. That is, when using a transparent soft vinyl chloride film and performing multi-color printing from the back surface, the printing layer will be laminated with a plurality of color layers, but the uppermost layer of the printing layer, that is, the printed soft vinyl chloride film The layer exposed on the back surface is printed on the entire surface with a white ultraviolet curable ink.

The relief plate 50 of the plate cylinders 18a to 18g of this embodiment is made of a nylon photosensitive resin relief plate.
As shown in FIG. 2, the nylon-based photosensitive resin letterpress includes a substrate 52 made of a polyester film or a steel plate. An adhesion and antihalation layer 54 is formed on the substrate 52. Further, the antihalation layer 54
On this, a photosensitive nylon resin layer 56 is formed. Then, an anti-adhesion layer 5 is formed on the photosensitive nylon resin layer 56.
8 is formed, and a cover film 60 is temporarily adhered on the anti-adhesion layer 58. Fig. 3
As shown in (a), the cover film 60 is peeled off, and the emulsion surface of the negative film 62 is brought into close contact with the photosensitive nylon resin layer 56. Next, as shown in FIG.
Exposure is performed by irradiating an ultraviolet ray of 00 to 400 nm. As a light source, a resin plate exposure machine 64 equipped with a chemical lamp or an ultra-high pressure mercury lamp is used. As such a nylon-based photosensitive resin letterpress, for example, Printerite (registered trademark) manufactured by Toyobo Co., Ltd. can be used.

Next, as shown in FIG. 3 (c), the negative film is removed, developed with tap water using a designated washing machine 66, and water on the printing plate is thoroughly removed with a sponge roll. As shown in FIG. 3D, drying is performed by the hot air dryer 68. Further, post-exposure is performed as shown in FIG. 3E for the purpose of increasing the adhesive strength of the relief and increasing the plate surface hardness. The light source 70 uses a chemical lamp or an ultra-high pressure mercury lamp. The nylon-based photosensitive resin letterpress used in the present embodiment,
Excellent resolution and reproducibility, excellent plate thickness accuracy and printing durability. According to the nylon photosensitive resin relief printing plate, a clear image can be obtained on the surface of the soft vinyl chloride film / sheet.

As a lamp of the ultraviolet irradiation devices 20a to 20h for curing the ultraviolet curing ink, for example, a metal halide lamp is used. However, a lamp suitable for the ultraviolet curable ink may be appropriately selected, and a high-pressure mercury lamp may be used. Also, aluminum mirrors and cold mirrors are generally used as reflectors disposed near the ultraviolet lamp. However, in this embodiment, adverse effects such as deformation of the vinyl chloride film due to heat generated from the ultraviolet lamp are provided. To prevent this, a cold mirror is used.

In the present embodiment, ultraviolet irradiation is performed while cooling the soft vinyl chloride film with the cooling rolls, because the cold mirror alone does not provide sufficient heat control. Thereby, in this embodiment, the soft vinyl chloride film temperature is set to 6
Since ultraviolet irradiation can be performed while maintaining the temperature at 5 ° C. or lower, deformation of the soft vinyl chloride film due to heat can be sufficiently prevented.

[0029]

As described above, in the method for printing a flexible vinyl chloride film / sheet according to the present invention, while the flexible vinyl chloride film / sheet is continuously transferred, it is cured with a letterpress using a letterpress rotary printing machine. Printing with mold ink,
Thereafter, it is wound into a roll. Therefore, in a further processing step, if the roll is rewound again, the film / sheet can be pulled out, so that there is no need to use a slip agent. Therefore, transfer failure of the printing ink caused by the slip agent does not occur. Further, in the method for printing a flexible vinyl chloride film / sheet according to the present invention, since the printing is performed continuously with a photosensitive resin relief printing plate using a letterpress rotary printing press with an ultraviolet curable ink, the flexible vinyl chloride film / sheet can be manufactured at low cost. And a method that is suitable for small-lot printing and that also contributes to energy saving. Furthermore, when curing the ultraviolet curable ink, the film / sheet is irradiated with ultraviolet light while being cooled, so that adverse effects due to deformation of the film / sheet due to heat normally generated from the ultraviolet irradiation device can be prevented, Print defects are less likely to occur. According to the method for printing a flexible vinyl chloride film / sheet according to the third aspect of the present invention, the surface of the flexible vinyl chloride film / sheet is subjected to corona discharge treatment before the printing step. Fixability can be improved. Further, according to the method for printing a soft vinyl chloride film / sheet according to the fourth aspect, the method includes the step of removing the charge of the film / sheet, so that the discharge generated during the post-processing and the adsorption of dust that hinders the fixation of the ink are prevented. Inconvenience due to charging can be prevented.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one example of a letterpress rotary printing apparatus used in the present invention.

FIG. 2 is an illustrative view showing a structure of a relief printing plate;

FIG. 3 is an illustrative view showing a method of making a relief printing plate;

[Explanation of symbols]

Reference Signs List 10 letterpress rotary printing device 12 chassis 14 impression cylinder 16a, 16b, 16c, 16d, 16e, 16f, 1
6g Print manufacturing units 18a, 18b, 18c, 18d, 18e, 18f, 1
8g Plate cylinder 20a, 20b, 20c, 20d, 20e, 20f Ultraviolet irradiation device 22 Impression cylinder 24 Cooling roll 26 Supply reel 28 Corona treatment device 30 Edge guide 32 Static elimination brush 34 Winding reel 36 Infeed roll 38 Outfeed roll 50 Top plate 54 Anti-adhesion and anti-halation layer 56 Photosensitive nylon resin layer 58 Anti-adhesion layer 60 Cover film 62 Negative film 64 Ultraviolet exposure machine 66 Washing machine 68 Hot air dryer 70 Light source

Claims (4)

(57) [Claims] 1. A step of preparing a soft vinyl chloride film / sheet in a roll-up state without applying a slip material in a rolled state; a step of continuously drawing the soft vinyl chloride film / sheet out of the roll; Printing on the soft vinyl chloride film / sheet with an ultraviolet-curable ink using a letterpress using a letterpress rotary printing machine; and irradiating ultraviolet rays while cooling the soft vinyl chloride film / sheet to cure the ultraviolet-curable ink. And printing the flexible polyvinyl chloride film / sheet in a roll. 2. The method for printing a flexible vinyl chloride film / sheet according to claim 1, wherein the photosensitive resin letterpress is formed of a nylon-based photosensitive resin. 3. The flexible vinyl chloride film / sheet printing method according to claim 2, further comprising a step of performing a corona discharge treatment on a surface of the flexible vinyl chloride film / sheet before the printing step. 4. The method for printing a flexible vinyl chloride film / sheet according to claim 1, further comprising a step of removing charge of the flexible vinyl chloride film / sheet.