JPS5857993A - Surface protection of prints - Google Patents

Abstract

PURPOSE:To completely protect an inked film after printing on a treated material by applying a nipping pressure onto a layer of a coating agent of the treated material at an entrance of a substance to press and convey. CONSTITUTION:A cardboard 18 is fed into a roll-coating device 1 from a paper carrier portion 8 while placing the inked film upward, and an ultraviolet-hardening type coating agent C is coated on the surface of the cardboard 18. Next, a nipping pressure is applied by holding between rollers 10, 13, by which the cardboard 18 is pressed to adhere, and the layer of the coating agent C is pressed for coating by a film belt 12 stretched between the rollers 10, 11, and bubbles and rolling marks on the layer of coating agent C is removed. The layer of coating agent C and film belt 12 which pass through the rollers 11, 13 are adhered each other unitarily, and hardened by bridging of the ultraviolet hardening coating agent at the next ultraviolet ray irradiation 16. Thereafter it is cooled off by a cooling device 17 and a deform between the belt 12 and the hardened layer of coating agent is generated, and the belt 12 easily comes off from the hardened layer at a separating roller 11, and it is accommodated as treated products in a receiving vessel 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for protecting an ink film printed on the surface of a treated material such as a plastic board or paperboard.

Conventionally, after printing on the surface of plastic plates, folding carton paperboard, etc., surface treatments are often carried out to protect the ink film, impart surface gloss, etc. Typical examples include coating methods and laminating methods.

The former involves coating with nitrocellulose lacquer or vinyl-based paint (PVC and acetate), and there are two types of coating methods: offset and direct. Carendanis method,
In the case of vinyl paints, there is a Rusucoat method in which after the paint is dried, heat and pressure is applied using a 7-layer plate to give it a glossy finish. With any of these coating methods, roll marks and uneven spraying occur in the coating film during coating, resulting in poor smoothness. Correcting these problems requires time for the coating film to flow, resulting in a decrease in line speed. In particular, this results in longer fins and requires a polishing process after drying.

The latter is a method in which, for example, a 20/1 polyvinyl chloride or acetyl cellulose film or the like is pasted with an adhesive and treated with a ferro plate under heat and pressure in the same way as press coating, but the cost is high.

Moreover, since both the former and the former use solvent-based diluents in the paints or adhesives, this is a major problem in terms of pollution, as the diluents form a black color when drying, worsening the working environment. Furthermore, the paints and adhesives used are thermoplastic resins because of the need for gloss.

It has drawbacks such as poor chemical resistance and magic resistance.

The present invention solves the above-mentioned conventional problems and has nine features.
According to the present invention, the ink film printed on the surface of the treated material such as plastic board or paperboard is completely protected, and the surface is given mirror-like smoothness and gloss, or partially or It is possible to make the entire surface a pear surface,
Moreover, the method of the present invention can be carried out at extremely low cost, and the gist of the invention has been transported. Nip pressure is applied to the coating agent layer of the material to be treated, which has at least one surface coated with an ultraviolet curable coating agent, at the inlet of the pressure-bonding conveyor exposed from the plastic film belt placed on the coating surface, and then Afterwards, the coating agent is cured by irradiating ultraviolet rays through the film belt.

Embodiments of the present invention will be described below with reference to FIG.

゛In Figure 1, (1) is a roll coating machine,
wI! (Layer) Thickness adjustable lino (-Although a roll coater is shown, you may also use a gravure coater, etc. (2) is the applicator roll of the same machine, (3) is a metallicon roll, (4) ) is the doctor roll, (5) is the doctor plate, (7) is the backup roll, (8) is the paper feed section, (
9) respectively indicate the paper feeding sections. The applicator roll (2
) and Metallicon roll (3) is suitably 3 to 18:1, and is changed depending on the viscosity of the coating agent (0), but it is desirable to increase the ratio as the viscosity increases. helps eliminate roll marks that occur in the coating agent layer.

On the other hand, the rotation ratio of the ablator roll (2) and the top cover roll (7) is suitably 3 to 10:1, and the smaller this ratio is, the thinner the coating agent layer (film thickness) will be.

The rotation ratio of the rolls (21 (3) (7) is determined by determining the working speed.The thickness of the coating agent layer is determined by the condition of the treated surface of the material to be treated, which will be described later, and is generally determined by the roughness. For larger ones, smoothness can be obtained by making them thicker.The coating speed ti can be adjusted in the range of 20 to 100 mm.

The coating (paint) (C) used in the present invention is a φ ultraviolet curing type that does not use a solvent. Such a coating agent was selected.

Conventional solvent-containing quick-drying paints are low tv (21(3)
It dries immediately due to the friction between the coatings, which has the disadvantage that large roll marks appear when transferred, and quick-drying coatings have the disadvantage of drying poorly if the transfer speed after coating exceeds 50 strokes/min. This is the result of considering the conditions.

Examples of the ultraviolet curable coating agent (0) include those comprising acrylic, epoxy thread, polyester/I/ or urethane acrylate oligomers and a photosensitizer.

The viscosity at this time is 200~600 cps @ degree -
It is preferable to use this because low A/eye will not occur.

Next, to further explain the drawing in Figure 1, (IQ is a hot roll, its surface is chrome plated, and steam is introduced inside, so the temperature can be adjusted freely.) These rolls are peeling rolls whose surfaces are coated with rubber II#).These rolls have good UV penetration, are less susceptible to UV deterioration even in the air, and have a mirror surface with good heat resistance (thermal stability). For example, a polyester film or sheet (approximately 50 to 500μ) film bell) 02 (product name: Tetron film) is stretched, and one of the p10-lv film αD is a pivoting roll and the other is an interlocking roll. The film belt (3) is rotated in the direction of the arrow VC to circulate in the direction of the arrow. In addition to the above films, cellulose triacetate film, fluorinated ethylene film, L(ill poly-10-pyrene film,
Although PV mu film, polycarbon film, etc. can also be used, the most preferable results were obtained with polyester μ film. Q
Reference numeral 3 denotes a back-up roll corresponding to the hot roll 01, which forms a so-called nip roll in combination with the roll roller 01, and the roll Q3 is designed so that the nip pressure can be appropriately adjusted with respect to the low μα1. α4 is a discharge conveyor that is located after the raw vQSU and corresponds to the feed of the film belt @, 1*a2', and extends after the peeling roll αυ.Although the details are not shown, it is a guide using heat-resistant fibers. The members are arranged evenly. a
5 is a meeting, QeFi ultraviolet irradiation device 1, for example 80W
Ultraviolet rays irradiated from the four high-pressure mercury lamps with an output of /m2 pass through the film belt of the feeder and cure the coating agent. aη is the irradiation device (
This is a cooling device installed at the rear of the engine.

Next, the effect will be explained. The folding carton paperboard Qs shown in FIG. 5 has an ink skin S on its surface printed.

With this film a9 on the upper surface, the paperboard (to) is continuously fed from the paper feed section (8) to the roll coating machine (1). ζ
Here, an ultraviolet curable coating example (e) of 1 fcd and a suitable thickness is applied to the surface of the paperboard, and the paper is transferred to the paper feeding section (transfer section) and then loaded into the roll αqQ3.

Here, the raw AlO3 applies an appropriate niche pressure (for example, 100 to 250 Kg/cxl) to the roll α, so the paperboard Qe located at the bottom of the roll Ql) is pressed W, and the coating agent (0 ) layer is low 14/QO(
2) Pressure contact of the film belt stretched between the two),
Air bubbles in the agent (0) layer and roll marks somewhat thick on the surface are almost completely removed. Thus, when the roll αoaa=i passes, the coating agent (layer (3) and film μ) Qa
d They adhere together under a vacuum condition and are transported to the lower part of the primary ultraviolet irradiation device (2), where the ultraviolet rays irradiated from the device side pass through the film belt ■ and the coating agent (C ) layer, ie, the UV-curable coating, crosslinking occurs immediately and curing is completed. Then, when the film belt Qa'fr is cooled by the cooling device αη, distortion occurs between the film belt υ and the coating agent cured layer (C)', so that the film belt 0 easily separates from the cured layer at the peeling roll 0 portion. (C) It is peeled off from ', and is collected in a collection chamber (18) as the treated product shown in FIG. 3(A).

What is shown in Fig. 2 is another embodiment of the present invention, in which the coating agent (C) is applied to the treated material printed on both the front and back sides of a paperboard (towards) as shown in Fig. 3. This is a case where surface gloss is imparted and the ink skin @QI is protected, and roll coating 5 (1) is omitted and is shown as a companion.
In this embodiment, a coating machine that can coat both sides simultaneously may be used as appropriate. In this figure, the part that corresponds to Fig. 1 is that the set of roll αQQ1) film belt @ ultraviolet irradiation device αG cooling device G is arranged in pairs in mutually symmetrical positions. The role of the backup roll D can be designed so that either roll QO (l) can perform the role, or the discharge conveyor Q in Fig. 1 can perform the role.
4 The Fi-side film belt (6) accomplishes that task.

Note that FIGS. 1 and 2 show only nine basic embodiments of the present invention, and for example, they are arranged in the vertical direction! the law of nature,
Even if a tension row or the like is used between the rolls σ00, it will cause a swipe.

The present invention has been conveyed as described above. For the coating agent layer of the material to be treated, on which at least one surface is coated with an ultraviolet M-curable coating agent, a roll (roll) (roll) (roll) 2, a film bell) Ql, and a backup roll 1 are placed on the coating side.
Pressure 11F consisting of a set of L103vI output conveyor (b), etc.
Since nip pressure is applied at the entrance of the JI feeder, the film belt 0 is pressed against the coating agent layer at the same time, air bubbles in the agent layer are removed, and some rolls remaining from the previous process are removed. The eyes, etc. are erased, and the film Peltro and the coating agent layer are strongly integrated with the sheet spread out in the vertical position, and the next ultraviolet irradiation device (2) is irradiated with ultraviolet rays through the film belt bent pipe. During curing, the mirror surface of the film remains transferred to the surface of the curing agent layer (C)' and curing is completed, resulting in a mirror surface. In other words, it is possible to process a smooth and shiny surface, and the ink I31! l[Q9 complete tt
It was possible to do c*a.

In the above explanation, the surface in contact with the coating agent layer on the film belt side is mirror-finished, so the surface of the curing agent layer (C)° is designed to have a mirror-finished surface. If the surface of (2) is partially or entirely satin-finished, the surface of the curing agent layer (C)' will be satin-finished as described above, and such a method also belongs to the present invention.

In particular, the most significant feature of the present invention is the use of plastic film tape Qa for the crimping conveyor belt, and if friction scratches occur during operation, it can be replaced immediately and easily, and it is inexpensive. It is. Moreover, since the irradiation with ultraviolet rays can be performed via this film belt (2), the irradiation device a6 is connected to the tension row 1vo4(u) of the same belt (■).
It can be installed between the two, making the entire device more compact. Furthermore, since the present invention uses an ultraviolet curable coating agent, unlike conventional solvent-based coatings, which have problems in terms of pollution, these problems have been completely eliminated.

Examples of the present invention will be described below.

<Example 1> Composition of coating agent Arc One 101 (acrylic type) ([Product name manufactured by Nie Daiichi Paint Manufacturing Co., Ltd.] Acrylic polyfunctional oligomer soo Weight a
1.6 hexanethionyl acrylate 100
#Trimethyl (10 pantriacrylate) 150
1/2 ethylhexyl acrylate 85
〃Monocizer TD1570mm 50
(WJ product name Nippon Ink ■) Benzopheno-A' 50
#Irgacure l-651300 (Product name: Manufactured by Chipagaiki Co., Ltd.) Dimethylaminoethanol 30 〃Silicon 8H2f3pm s m1is
(Product name: Made by Nitoshi Silicone ■) The coating agent with the above composition is coated on paperboard (printing material) printed on reverse roll paper, and this is applied to polyester A4A/M (thick paperboard). : 1
A nip pressure was applied at the inlet of a pressure layer conveyor such as a film belt of 50μ), and the film was passed under ultraviolet irradiation of 80 W/era x 4 lights at a speed of 30 m/min to ensure peeling after cooling. A coating hardener layer (paint film) with a mirror surface can be formed on the printing material, and this [1llK
When the following test was conducted on the product, the following favorable results were obtained.

■Adhesion test: A 24m wide piece of Nichiban cello tape was attached to the processed surface with a pressure of 5 to 10 mm, held in a device for 1 minute, and then peeled off at once in a 90° direction. There was no abnormality in the film.

■Itjl1M test: Loaded using a Sazafradofbot tester] [6 bonds were applied and repeated 100 times, but no abnormality was found. (Using Toyo F paper 12) ■10 packing 1) l (Test: 50℃, 75℃ constant temperature bath, charged with 500B and exposed for 24 hours.No abnormality was found.〈Example 2-4> As a coating agent, the following (composition I) was used, and the rest was the same as in Example 1.

Example 2 Arc One 110 (epoxy type) Arc One 110 100 parts by weight Arc One hardener 3 Example 3 Arc One 120 (polyester type) Arc One 12
0 100 parts by weight Arc One Hardener
3 The test results of Examples 1 to 4 above are shown in the table below. OFi Good O Good Good Δ Average

[Brief explanation of drawings]

The drawings show an embodiment of the method of the present invention, FIG. 1 is an explanatory diagram of the whole of one embodiment, FIG. 2 is an explanatory diagram of the main part of another embodiment, and the third factor is obtained by the method of the present invention. FIG.

Claims (1)

[Claims] 1 A plastic fin placed on the application side of the coating agent layer of the transported material coated with an ultraviolet curable coating agent on at least one surface.
Nip pressure is applied at the entrance of the crimping conveyor made of a belt,
Thereafter, the coating agent is cured by irradiating ultraviolet rays through the film belt to form an ink layer after printing on the FIA material. 1lIt-A method for protecting the surface of printed matter, characterized in that it protects the surface of printed matter.