JPH0592541A - Gravure offset printing method - Google Patents

Abstract

PURPOSE:To continuously print at high speed a body to be printed which has been unable conventionally by using a convex roller of crest shape formed by a rubber flexible polymer substance as the body interposed in the middle when a printed image on an intaglio is transfer printed indirectly to the body to be printed. CONSTITUTION:A waterless deep-etch offset plate of a polyester film base of 1-10 micron convex depth as an intaglio is mounted and fixed on a plate cylinder 11 on which crest convex rollers 12 formed in two tows are closely mounted. Two inking units 10 provided with various kinds of ink kneading roller for inking are added in units to the plate cylinder 11. The printing mode is taped and two IC chips 13 of different size fixed at equal pitch can be printed at high speed simultaneously.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intaglio special printing method.

[0002]

2. Description of the Related Art Generally, intaglio printing is performed by direct printing known as gravure printing and an ink transfer roller called a bracket, which is in contact with an intaglio plate and once transferred to the roller to transfer the ink (image) on the roller to a printing medium. Indirect printing for printing (known as offset printing) is known. Since these are rotary-type continuous high-speed printing, the printing target is printing on a film or paper such that the printing surface is flat and continuous. On the other hand, there is a method called pad printing. This can be printed on an object to be printed having a curved surface (unevenness, three-dimensional surface, etc.), such as a golf ball and electronic parts. Depth 20
Ink is filled in a metal or photosensitive resin intaglio plate of -30 μm with a doctor blade, the ink (image) in the recess is received by a silicon pad, and the ink is pressed against a printing medium for printing. That is, printing is performed one by one discontinuously.

[0003]

The development of a technique capable of continuously printing at a high speed even on an object to be printed having a curved surface with an uneven surface is one of the problems in the industry, but the conventional technique solves this problem. The reality is that we cannot do it. The present inventor has earnestly studied this technical problem and arrived at the present invention.

[0004]

This object is achieved by the following method. In intaglio offset printing in which intaglio printing is performed indirectly through an ink transfer roller, the ink transfer portion of the roller is a convex convex roller made of a polymer having rubber elasticity and having a continuous shape. In addition, the intaglio plate in this printing is a waterless planographic intaglio plate having a depth of 1 to 10 μm, and the intaglio offset printing method is combined with the convex roller of the present invention.

In the present invention, the intaglio plate is a generally known intaglio plate made of a metallic or photosensitive resin, and the depth of the indented plate is about 10.
~ 50 microns. This plate is produced by a commonly used photoengraving method. Printing with these plates is an intaglio plate with a plate made and an image is obtained in the form of a rotating body or a flat plate, but the ink is automatically placed on the entire plate surface, and then the plate surface is rubbed with a doctor blade to form recesses (image). Indirect non-continuous pad printing in which ink is left only on the surface and the ink in the recess is directly transferred directly to the printing material such as a film or is received by a silicone rubber pad and finally transferred to the printing material. Is. In these conventional intaglio printing methods, the ink on the plate surface is scraped off with a doctor blade, so that the plate is scratched or worn out by abrasion, that is, abrasion resistance is poor. Further, there is a limit to the reproducibility of the printed image, and particularly fine characters and pictures cannot be reproduced. These conventional printing methods are problematic because modern printing tends to be done on very small products. Therefore, in the present invention, a waterless planographic intaglio plate was found as an intaglio plate, and the indirect printing method in combination with the convex roller of the present invention has a line width of up to 20 μm.
Moreover, an epoch-making method in which characters can be reproduced in a 1 mm square is particularly effective. This waterless planographic intaglio plate is made of polyester film, aluminum plate, iron plate, etc. as a substrate, on which urethane resin-based or phenol novolac resin-based photocurable or photodegradable photosensitive resin is applied, and then the lower layer Resin layer and an active and ink-repellent silicone rubber are applied, and the depth of the silicone rubber layer is 1-10.
The thickness is the micron, preferably 2 to 5 micron, and this thickness is the depth of the recess after the plate making. In the plate-making method, a negative or positive image film is vacuum-contacted with the silicone rubber layer surface and irradiated with ultraviolet rays. Only the exposed portion of the silicone rubber is removed or remains by being removed by the developing solvent. What is removed here is a negative type waterless planographic relief plate, and what remains is a positive type. In the case of a negative type, it is preferable to treat with a pretreatment agent before development to enhance the adhesion between the silicone rubber layer in the unexposed portion and the lower resin layer. The depth of the concave portion of this plate is extremely shallow, which is different from the conventional metal plate which scrapes off the ink on the plate surface with a doctor blade. That is, it is 10 microns or less, but if it is deeper than 10 microns, the reproducibility of a fine image tends to be poor, and conversely, if it is shallower than 1 micron, the density of the printed ink is thin, making it difficult to read. Further, in the printing using the waterless planographic printing plate, if the ink is inked on the plate surface with an inking roller, the ink enters only in the recesses (images), and thus the conventional doctor blade for scraping the ink is unnecessary. The silicone rubber layer, which is the non-image area, needs to completely repel the printing ink, but it is also preferable that the ink itself repels the silicone rubber layer for more complete repulsion. Ingenuity in the machine itself is also desired. In other words, the number of inking rollers (that is, the rollers that contact the plate) is two or more,
Moreover, it is preferable to consider cooling the plate surface temperature to around 20 ° C. Next, the roller for transferring ink, which is the most important part of the present invention, will be described. This roller is not a normal flat and hard rubber roller inkin transfer from intaglio,
It is a mountain-shaped convex roller with a continuous ink transfer surface, and the material is a polymeric substance with rubber elasticity, and the hardness (Shore A
It is preferable that the hardness is about 5 to 50 °, preferably 10 to 30 ° and is soft. This is because the relief and soft rubber elastic body can print on uneven surfaces with high printing quality. Further, since it is a convex roller, the pattern to be printed may be a continuous pattern or a discontinuous pattern, and printing can be performed at high speed without selecting the size of the material to be printed or the printing place.
The height of the convex portion and the size and shape of the top portion (that is, the ink receiving portion) are not particularly limited, and may be appropriately determined depending on the shape and size of the material to be printed, the printing place, and the print image content. A preferable rubber elastic polymer material is urethane rubber, silicone rubber, butadiene / acrylonitrile copolymer rubber or neoprene rubber.
In particular, when an ultraviolet curable ink is used as the ink, polyester-based urethane rubber or neoprene rubber, and butadiene / acrylonitrile copolymer rubber are preferable. Further, the manufacturing method of the mountain-shaped convex roller is not particularly limited. For example, first make a metal roller of the required size. On the other hand, make a chevron-shaped mold. This mold has a linear or circular shape having the circumferential length of the roller. A raw material of, for example, silicone rubber is poured into this mold, defoamed, and allowed to stand for a whole day or night or heated to cure. Take it out of the mold,
Wrap it around the metal roller body and fix it with adhesive. It may be formed according to each manufacturing condition of the material. In addition, it is preferable that the apex of the chevron convex roller, that is, the shape of the center of the ink transfer portion from the intaglio plate is rounded.

An example of the mountain-shaped convex roller will be described in detail with reference to FIG. 1 is a front view of a chevron-shaped (bottom width 15 mm) convex roller having a roundness of 1 at a vertex of 3R (radius 3 mm) and a height of 2 at 10 mm, which is molded from a polyester-based urethane rubber having a hardness (Shore A) 15. .. FIG. 2 shows the side view. Reference numeral 3 denotes a metal roller main body having a width of 15 mm and a diameter of 70 mm and having a rotating shaft 4 at the center, and a mountain-shaped polyester urethane rubber is adhered and fixed onto the surface of the roller.

In the convex roller of the present invention, the chevron-shaped ink transfer portion on the roller body is not limited to one row, but may be two or more rows. By using a plurality of rows of chevron rollers, in addition to further increasing the printing speed, it is possible to perform different kinds of objects to be printed at the same time, and to perform different printing contents and color printing, which is extremely effective. This is illustrated by FIG. FIG. 3 is a front view showing the metal roller main body 9 and two differently shaped chevron convex rollers. In other words, the thermosetting silicone rubber with a rubber hardness of 20 °
It is a convex roller with two different shapes. One is the top 5,
It has a roundness of 5R (radius 5mm) and its height is 2
As a continuous convex inkin transfer section of 0 mm, and as another one, the convex ink transfer sections having a roundness of 2.5 R like the top section 6 and a height of 20 mm are independently arranged in two rows. It is a convex roller. 8 is a rotating shaft. Of course, in this case, the printing patterns on the intaglio plate are made into two rows, are formed, and face the convex roller.

[0008]

Next, an example showing the whole intaglio offset printing of the present invention will be described in detail with reference to FIG. As shown in Fig. 4, a waterless planographic intaglio plate (negative type) of a polyester film substrate having a recess depth of 5 microns was mounted and fixed on the plate cylinder as an intaglio plate.
Mounted in a row are chevron-shaped rollers formed in rows. Two inking units in which various ink kneading rollers for inking are arranged are added to the plate cylinder. In this printing mode, two different sizes of IC chips, which are taped and fixed at equal pitches, are simultaneously printed at high speed. The whole shows a side view. In this figure, 11 is a plate cylinder equipped with a waterless planographic printing plate on which printed images are arranged in two rows at a fixed pitch, and 10 is two inking rollers and It is an inking unit to which various ink kneading and supplying rollers for supplying ink and an ink fountain are attached. The two rows of silicone rubber chevron convex rollers 12 shown in FIG. The inking roller and the convex roller are structured so that the contact width can be varied. 14 is an irradiator for curing uv ink. Reference numeral 12 denotes an IC chip in which a large number of tapings are fixed at an equal pitch, and printing is continuously performed on the convex surface of this chip. The chips are continuously supplied to the receiving jig.

[0009]

As described above, the present invention has a mountain-shaped convex roller formed of a rubber elastic polymer material as an intermediate object when the printing image on the intaglio is indirectly transferred and printed on the printing medium. Is used, which enables continuous printing at high speed on an object to be printed having an uneven surface, which was impossible with the conventional technology.

[0010]

EXAMPLES The present invention will be described in detail below with reference to examples.

The following negative type waterless planographic intaglio plate is prepared as an intaglio plate. A 125-micron-thick polyester film is used as a substrate, and a naphthoquinone-1,2-diazide-5-methyl sulfonate (44% esterification) solution of a phenol novolac resin is applied thereon to a dry thickness of 2 microns. To do. Next, a 0.5% Isopar E solution of di-n-butoxybistitanium is applied and dried in hot air at 120 ° C. to make the adhesion with the upper silicone rubber layer effective. Finally, an ink repellent silicone rubber layer is provided as the upper layer. This layer is formed by the following method. That is, 5 parts by weight of methyltriacetoxysilane and 0.2 parts by weight of dibutyltin acetate were dissolved in an Isopar E solvent with respect to 100 parts by weight of polydimethylsiloxane having a molecular weight of about 80,000 and having hydroxyl groups at both ends, and this solution was applied, Dry with hot air at ° C to give a 3 micron silicone layer. The protective film is laminated as a product on the surface of the silicone layer. The waterless intaglio plate thus obtained is prepared by a photoengraving method. In other words, with a transparent wire with a line width of 40-60 microns, 1
The product name, the manufacturing date, the lot number, the company name, and the product name are symbolized in a 0 mm square, and 40 characters are drawn at 3 mm pitch intervals as the print content on one printed material. Make a masking film for plate making. Next, this film is vacuum-bonded to the cover film surface of the waterless intaglio material. Then 4 with a 2 kW metal halide lamp
Expose for 0 seconds. The cover film is removed, and the film is pretreated with an amine-based pretreatment solution for hardening. Finally, brushing is performed with a mixed solution of Isopar E and ethyl alcohol, and the silicone rubber in the exposed area (image) is swollen and peeled off and developed. After washing with water and drying, a printing plate is obtained. Recessed area (image area that receives ink)
Depth was 3 microns. This printing plate has a diameter of 163
mm and a width of 17 mm are fixed by adhesion with a double-sided tape (referred to as A roll). On the other hand, a mountain-shaped convex roll is manufactured by the following method. Mountain peak is 7R (radius 7mm), height is 1
A metal mold having a length of 360 mm and having a mountain shape of 3 mm is prepared (width 15 mm). Into this mold, a silicone rubber liquid (Type D manufactured by Toray Dow Corning)
To 100 parts of Y35-110A / B, viscosity of 600 poise), 0.2 part of the curing catalyst (SRX-212 manufactured by the same company) was uniformly mixed, and the prepared liquid deaerated in vacuum under 5 mm was injected. Heat at 100 ° C overnight. This is taken out from the mold and adhered and fixed on a metal roll having a shaft of 150 mm in diameter and 17 mm in width at the center. Since there is a seam that uses silicone rubber for adhesion, fill the same silicone rubber liquid into this using a jig and heat-cure it in the same way to form an endless chevron rubber roll. .. (Called B roll). A roll and B
A printing machine having a mechanism that allows continuous printing by contacting the material to be printed with the roll and the B roll is prepared. To A roll Figure 4
Of 10. The inking unit shown in is attached. The actual printing is performed as follows. Put the UV-curable ink for waterless planographic printing plate made by Toyo Ink Co., Ltd. in the ink fountain of A roll. Drives the entire printing press. The ink that has reached the inking roller adheres only to the recesses of the waterless planographic plate on the roll A plate cylinder, and the ink repels the other silicone rubber parts and does not ride at all. Subsequently, the ink of the concave portion is transferred to the convex portion of the B roll. When an IC chip having a lead wire with a diameter of 12 mm was supplied to the B roll at a pitch of 3 mm, it was printed well on the IC chip. This printing speed is 12000 pieces /
It was time. In addition, when this printing is performed by the commonly used pad printing, the number is 5000 even at the maximum speed.

[0012]

The following raw materials are poured into the chevron mold used in step 1.
Polyester polyol (viscosity 1025 centipoise,
To 100 parts of a hydroxyl value of 57 to 64), 7.5 parts of toluylene diisocyanate is added and mixed with stirring. At this time, heat is generated due to the reaction, so cool it so that the temperature does not exceed 90 ° C. Immediately after the reaction, the reaction solution degassed under reduced pressure is injected. After the injection is completed, the mixture is cured by heating at 120 ° C for 6 hours. The obtained chevron urethane rubber was taken out of the mold and the rubber hardness was measured to be 20 °. this

It was wound around the roll used in (1) and fixed by adhesion. The same reaction urethane rubber liquid as described above was poured into the seam using a jig, and heat-cured at 120 ° C. for 6 hours to produce an endless chevron roll. Using this polyester urethane rubber convex roll

Printing was performed with the same machine in contact with the A roll of No. 1, and the same result was obtained. In addition, with this convex roll

The suitability of the silicone convex roll of UV curable ink was checked. That is, the ink was dipped in the ink for 3 days and the swelling property was observed. The silicone convex roll showed swelling of 7%, but the urethane convex roll of this experiment was only 0.2%.

Using an RG plate for gravure printing (Toray HG plate, type RG / 25A) in which an alcohol-soluble photosensitive polyamide resin is coated on a 125 μ polyester film, the product name and lot number are placed in a 4 mm square. , The date of manufacture, the company name is drawn, and it is 20
An RG plate intaglio plate is prepared by exposing, washing, drying, and then exposing 10 positive films having a pitch of mm by a photomechanical process. This is adhered and fixed to a metal roll having a circumference of 250 mm and a width of 8 mm with a double-sided tape. Align the cut surfaces so that the seams are diagonal. On the other hand, a mountain-shaped continuous circular mold having a vertex of 2.5 R (radius 2.5 mm), a height of 7 mm, and a bottom width of 7 mm is produced. The size of this circular mold is determined so that it has the same circumference as the C roll. Silicone rubber liquid (Type DY35-109A / B, viscosity 300
Poise) 100 parts of curing catalyst, 0.2 parts (SH-212 manufactured by the same company) are mixed evenly to obtain 5 mmH.
The degassed vacuum degassed formulation is injected. Heat at 100 ° C overnight. This circular mold is designed to be divided into two at an angle. Divide into two to make an endless chevron roll. This is put into a metal roll made separately, and fixed with adhesive silicone rubber. An endless chevron roll can be obtained. (Called D roll) Next, the C roll and the D roll are placed in contact with each other, and fixed below the D roll at a pitch of 20 mm so as to come into contact with the bottom of a glass cosmetic bottle as a material to be printed. The jig is fixed to the conveyor belt. Further, an irradiator (1 KW metal halide lamp) for ultraviolet-curing the printing ink on the material to be printed on the conveyor belt is attached.
Further, the C roll is provided with a ceramic doctor blade for scraping off the ink on the plate surface and an ink supply tank with a supply nozzle for supplying ink to the plate surface. With the above printing apparatus, first, the ink is left only on the concave image portion on the RG plate which is supplied with the epoxy ultraviolet curing ink on the C roll and is rotated. This ink transfers onto the D roll. Since the D roll contacts the glass bottle of the material to be printed,
The transfer image of the mountain top of the D roll is transferred to the bottom of the glass bottle, and printing is continuously performed. Printing speed is 800
It was 0 pieces / 1 hour.

The following experiment is conducted as a comparative example. The above

Similar printing is performed by using the following ordinary flat transfer rubber roll instead of the D roll. That is, first, the flat roll is manufactured by the following method. The main body metal roll is covered with a circular mold so that the gap is 10 mm. A similar silicone rubber liquid is poured into this gap and heat-cured. A flat rubber roll is obtained (called E roll). This E roll was similarly printed relative to the C roll and printed on the bottom of the glass bottle. On the bottom of the glass bottle, a part of the printed characters was printed only in the center. This is because the transfer roll was flat and did not completely contact the bottom of the glass bottle, but only partially contacted it. (The bottom of the glass bottle is 3mm high.
There is a border)

[0015]

The present invention exhibits the following various effects, and can be said to be an extremely remarkable breakthrough invention as compared with the generally used pad printing or gravure offset or letterpress offset printing. A. A printing object having an uneven surface can be printed continuously and at high speed. B. Any material can be printed regardless of the material of the material to be printed. C. Since an extremely fine image is reproduced by printing, it is possible to continuously print even a small object to be printed (especially electronic parts). D, in particular, a waterless planographic printing plate is used, and by using a plurality of chevron convex rolls, different printing materials or different printing contents can be printed continuously at the same time.

[Brief description of drawings]

FIG. 1 is a front view of a row of chevron-shaped convex rolls made of polyester-based urethane rubber.

FIG. 2 is a side view of FIG.

FIG. 3 is a front view of two different mountain-shaped convex rolls made of silicone rubber.

FIG. 4 is a side view showing the entire continuous printing on two different IC chips by using a waterless planographic intaglio plate as an intaglio plate and combining two rows of silicone rubber-based chevron convex rolls as a transfer roll.

Claims (2)

[Claims] 1. Intaglio offset printing in which intaglio printing is performed indirectly through an ink transfer roller, the ink transfer portion of the roller is made of a polymer material having rubber elasticity, and its shape is continuous. An intaglio offset printing method characterized by being a convex roller. 2. The intaglio offset printing method according to claim 1, wherein the intaglio plate is a waterless planographic intaglio plate having a depth of 1 to 10 μm.