KR20100138529A - Blanket for roll-printing having a barrier layer between printing layer - Google Patents

Abstract

PURPOSE: A print blanket with a barrier layer between the surface printing layers is provided to remarkably reduce swelling of the surface printing layer. CONSTITUTION: A blanket for off-set printing comprises a surface printing layer(a,b), support layer, cushion layer and barrier layer which prevents absorption of solvent between the surface printing layers. The barrier layer is formed by a material selected from polyethylene terephthalate(PET), polyethylene, and polypropylene. The thickness of the barrier layer is 5-15 um.

Description

BLANKET FOR ROLL-PRINTING HAVING A BARRIER LAYER BETWEEN PRINTING LAYER}

The present invention relates to a printing blanket, and more particularly, to a printing blanket further comprising a barrier layer between the surface printing layers.

In general, electronic devices such as liquid crystal display devices and semiconductor devices are fabricated by forming a pattern of numerous layers on a substrate. In order to form such a pattern, a photolithography process has been mainly used until now.

However, the photolithography process has to produce a predetermined pattern mask, and the chemical etching and stripping processes have to be repeated, thus making the manufacturing process complicated and generating a large amount of chemical waste harmful to the environment. This, in turn, leads to an increase in manufacturing costs, which reduces the competitiveness of the product.

A roll printing method using a printing roll has been proposed as a new pattern forming method for solving the disadvantages of the photolithography process.

There are various methods of roll printing, but it can be roughly divided into two types, gravure printing and reverse offset printing.

Gravure printing is a printing method that scrapes excess ink by printing ink on a concave plate and prints it. It is known as a method suitable for printing in various fields such as publishing, packaging, cellophane, vinyl, polyethylene, and the like. Research has been made to apply the gravure printing method to the fabrication of the active element or circuit pattern to be applied.

Since gravure printing transfers ink onto a substrate using a transfer roll, by using a transfer roll corresponding to the area of a desired display element, a pattern can be formed by one transfer even in a large-area display element. Will be. Such gravure printing not only forms an ink pattern for resist on a substrate, but also various patterns of the display device, for example, a TFT for gate lines and data lines, pixel electrodes, and capacitors connected to the TFT as well as a liquid crystal display device. It can be used to pattern metal patterns.

However, the blanket used for gravure printing is generally manufactured by casting a silicone-based resin into a rigid master mold. Thus, the blanket thus prepared is not only limited in manufacturing a uniform thickness, but also difficult to mass-produce on a pilot scale. have.

Thus, a reverse offset printing method is mainly employed for precise fine pattern formation.

For the prior art related to the reverse offset printing method and the printing apparatus, reference may be made to those of Documents 1 to 3, which are filed and published by the applicant of the present invention.

Document 1 is a printing roll; And a linear motor for moving in the front-rear direction while rotating the printing roll. The apparatus, by using a linear motor as a motor for driving printing rolls for coating and transfer, can minimize vibrations from the existing motors and provide a clean pattern without stains caused by vibrations.

Document 2 discloses a printing roll for a roll printing apparatus, and relates to a printing roll for a roll printing apparatus, characterized in that the cross-sectional area is reduced from the central region to both end regions.

Document 3 is a substrate; A substrate transfer device on which the substrate is mounted and which moves the substrate in one linear direction; A cliché disposed to face the plate surface of the substrate transfer device and having a pattern portion; A cliché on which the cliché is mounted so that the pattern portion of the cliché faces the plate surface of the substrate transfer device and moves the cliché in a straight line opposite the substrate transfer direction; A printing roll installed between the cliché feeder and the substrate feeder so as to be rotatable in the same direction as the cliché feed direction; And a coater for coating a coating on the printing roll, wherein the distance from the leading end of each of the substrate and the cliché to the central axis of the printing roll perpendicular to the linear direction is different from each other. At the initial positions of the substrate and the cliché spaced apart on both sides of the roll, the substrate and the cliché are linearly moved in opposite directions toward the printing roll on both sides of the printing roll simultaneously with the rotation of the printing roll. The coating is coated on the printing roll by the coater, and as the cliché passes over the rotating printing roll, the coating of the printing roll is transferred to the pattern portion of the cliché, and the printing roll is rotating on the printing roll. The process of transferring the coating pattern remaining on the printing roll to the substrate as the substrate passes by It discloses that on the roll printing device according to claim.

Document 1 KR 10-2008-0090890 (published) 2008.10.09.

Document 2 KR 10-2009-0020076 (published) 2009.02.26.

Document 3 KR 10-2009-0003883 (published) 2009.01.12.

All of the contents of the specification of Documents 1 to 3 are incorporated into the specification of the present invention as a description of the prior art of the present invention.

Figure 1 shows a structural cross section of a blanket conventionally used for reverse offset printing. As shown in Figure 1, the conventional blanket is composed of a surface printing layer, a support layer, a cushion layer, may be further provided with a primer layer to secure the adhesion between the layers. The surface print layer is a layer in which ink is directly buried and is transferred, and is mainly made of poly-di-methyl-siloxane (PDMS), and the support layer serves to support the surface print layer and the cushion layer and is mainly made of PET film. Is produced. In addition, the cushion layer, when the surface of the surface printing layer is not uniform, serves to compensate for such a thickness difference, and is mainly made of PDMS like the surface printing layer.

Reverse offset printing is a very popular technique in terms of cost reduction and production speed in pattern formation, but a high quality blanket is required to obtain a precise pattern. That is, manufacturing a high quality blanket for printing is a very important technical problem in that the quality of the pattern may depend on the characteristics of the blanket.

Factors to be considered for producing a good quality blanket include: a) thickness uniformity of the blanket, b) hardness of the surface printing layer, c) presence of foreign matter (bubbles, dust, etc.) in the blanket, d) substrate layer (substrate film). E) adhesion between the other layer, e) the introduction of the cushion layer to the process stability to the degree of performance, f) the slipperiness of the cushion layer, g) the content of the low molecular weight silicone oil contained in the surface printing layer, h) Swelling degree to the ink or solvent of the surface printing layer, and the like.

In particular, when the surface printed layer swells well with ink or a solvent, the time taken for the ink to dry becomes long, the process waiting time increases, and the process margin becomes poor.

Accordingly, the present invention is to provide a printing blanket of excellent quality and a method of manufacturing the barrier layer between the surface printing layer to significantly reduce the swelling degree of the surface printing layer.

The present invention has been made to solve the above problems of the prior art,

In the offset printing blanket comprising a surface printing layer, a support layer, and a cushion layer, there is provided a blanket for offset printing, further comprising a barrier layer for preventing absorption of the solvent between the surface printing layers.

In addition, in the present invention, the barrier layer provides a blanket for offset printing, characterized in that formed of at least one material selected from polyethylene terephthalate, polyethylene, and polypropylene.

In addition, in the present invention, the barrier layer provides a blanket for offset printing, characterized in that the thickness is within the range of 5 ~ 15 ㎛.

In addition, in the present invention, the barrier layer is provided with a blanket for offset printing, characterized in that formed in a position for dividing the thickness of the surface printing layer to 1: 1 ~ 1.5.

In addition, in the present invention, the printed layer provides a blanket for offset printing, characterized in that the sum of the thickness of the two layers bisected by the barrier layer is within the range of 10 ~ 1200 ㎛.

In addition, in the manufacturing method of the blanket for offset printing containing the surface printing layer, the support layer, the cushion layer, and the barrier layer which prevents absorption of a solvent between the said surface printing layers,

The barrier layer,

Applying a silicone resin to a predetermined thickness; And

It is formed by incorporating a surface printing layer comprising the step of depositing a film on the silicone resin,

The step of seating the film on the silicone resin, provides a method of manufacturing a blanket for offset printing, characterized in that made in the range of 20 to 50% of the pot life of the silicone resin.

The printing blanket of the present invention has an effect of reducing the process waiting time and improving the process margin since the surface printing layer is not swelled well by the ink.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

In the offset printing blanket comprising a surface printing layer, a support layer, and a cushion layer, the surface printing layer further comprises a barrier layer for preventing absorption of the solvent.

2 shows a structural cross-sectional view of the printing blanket of the present invention, which may be referred to in the description below.

In other words, the surface printing layer impregnates ink during the roll printing process, and the surface printing layer is provided with a barrier layer that prevents the solvent from being absorbed any more.

The barrier layer can be used without limitation as long as it is a material having excellent chemical resistance and no swelling property. Examples of such materials include those formed from one or more materials selected from polyethylene terephthalate, polyethylene, and polypropylene.

In particular, the barrier layer is preferably formed at a position that bisects the total thickness of the surface printed layer within the range of 1: 1 to 1.5. That is, it is preferable that the thickness (a) of the first surface printing layer and the thickness (b) of the second surface printing layer bisected by the barrier layer have the same or less than 20% difference.

If the thickness (a) of the first surface printing layer is formed too thin compared to the thickness (b) of the second surface printing layer outside the above barrier layer, the swelling property for the solvent may be improved, but it is suitable for printing. It may not be impregnated with the ink, so transfer may not be performed well during the set process. On the contrary, when the thickness (a) of the first surface printing layer is formed too thick compared to the thickness (b) of the second surface printing layer outside the above range of the barrier layer, it may be difficult to expect a swelling inhibiting effect on the solvent. .

In addition, the barrier layer preferably has a thickness within the range of 5 to 15 μm. If the thickness is less than 5 μm, the effect of inhibiting swelling of the solvent may be insignificant. If the thickness is more than 15 μm, the thickness of the barrier layer may be too thick, thereby affecting the barrier layer properties on the surface printed layer. There is a risk of adversely affecting.

Hereinafter, the manufacturing method of the present invention will be described in more detail in the step of forming each layer of the blanket of the present invention.

First, a substrate to be used for the printing blanket is prepared. The substrate serves as a support layer. As a base material, it is preferable to use the film with a small elasticity in order to suppress the expansion and contraction of a surface printing layer and a cushion layer, and to improve the precision of printing. In particular, a film of a resin having a tensile modulus of at least 1000 MPa at room temperature, particularly 2000 to 5000 MPa, is suitable. Examples of such films include polyester films such as polyethylene terephthalate (PET), polycarbonate films, and the like.

Although the thickness of a base material is not restrict | limited, It is suitable that it is 0.1-0.5 mm, and 0.2-0.45 mm is preferable. If the thickness of the substrate is less than this range, the effect of reinforcing and supporting the cushion layer or the surface printed layer by the substrate may be insufficient.

Next, a liquid mixture having a cushion layer formed on one surface of the substrate is prepared. The mixture is prepared by blending the liquid silicone resin and the hollow microspheres and mixing the hollow microspheres to be uniformly dispersed in the liquid silicone resin.

As the hollow microspheres, those disclosed in US Pat. No. 4,770,928 may be used. In particular, when considering the swelling prevention by ink, homopolymers of polymerizable monomers such as polymerizable monomers such as vinylidene chloride, (meth) acrylonitrile, or monomers thereof Hollow microspheres in which the shell is formed of a copolymer containing two or more kinds are preferable.

Although the particle size of a hollow microsphere is not specifically limited, In order to exhibit the effect of adjusting the phosphorus pressure by a cushion layer favorably, it is preferable that the average particle diameter is 20-200 micrometers, especially 40-150 micrometers.

The hollow microspheres are suitably blended in an amount of 1 to 30 parts by weight based on 100 parts by weight of the liquid silicone resin. When the blending ratio of the hollow microspheres is less than this range, the effect of adjusting the pressure by the cushion layer is not obtained. In addition, when the blending ratio of the hollow microspheres exceeds this range, the cushion layer becomes soft and the printing precision is lowered. In addition, the viscosity of the mixture is high, making it impossible to uniformly apply the mixture to the desired thickness.

Next, at the same time, the mixture is applied to one surface of the substrate, and the silicone resin is cured in a state where the substrate is held horizontally to form a cushion layer. For this purpose, it is possible to use a surface plate and the like. In this way, the mixture becomes hard and uniformly formed by its own weight, and at the same time, the hollow microspheres have a gradient in the thickness direction.

In order to apply the mixture to one surface of the substrate, a roll coater, bar coater, flow coater, gravure coater, spray, applicator, or the like may be used. Moreover, it is preferable that a base material is a state in which the horizontality was fully maintained, and it is preferable that a base material is a state in which the base material adhered closely to a horizontal object. To this end, a method of applying a tensile force on both sides of the base film and bringing it into close contact with the surface of the horizontal band (or surface plate), having a fine suction hole in the horizontal band, and inhaling it through the horizontal band may be used.

The silicone resin may be thermosetting, room temperature curing, catalyst curing, or the like. However, in the embodiment of the present invention, a catalyst curing type was used. After the mixture is applied, it is allowed to stand for a certain period of time under a room temperature environment (23 ± 3 ° C.) without heating and to undergo a curing reaction. This is preferable because it can prevent volatilization of low molecular weight silicone oil, prevent expansion and destruction of hollow microspheres, and save heat energy required for the curing process.

The thickness of the cushion layer is not particularly limited, but is preferably 0.05 to 2 mm, more preferably 0.3 to 1 mm. If the thickness of the cushion layer is less than this range, there may be a possibility that the pressure control effect of the cushion layer may not be sufficiently obtained. If the thickness of the cushion layer is exceeded, the thickness of the substrate may be relatively small, which may cause a problem that the supporting effect between the layers of the substrate may be lowered. There is.

Next, a surface printing layer is formed on one side of the other side of the substrate. The surface printed layer is a nonporous layer. Such a non-porous surface printing layer may be formed according to various forming methods. Specifically, the liquid silicone resin is cured while the liquid silicone resin is applied to the opposite side of the substrate and the substrate is kept horizontal. The method of forming the surface printing layer integrated with a base material is preferable.

In particular, in order to form the barrier layer between the surface printing layers, the silicone resin is applied to a predetermined thickness of about half of the total thickness of the desired surface printing layer, and then the barrier film is placed thereon, and then the other half of the surface printing layer. It is possible to use a method of applying a silicone resin on the thickness thereof.

At this time, the time for placing the barrier film on the silicone resin is about 20 to 50% of the pot life (the time when the viscosity increases twice as much as the initial viscosity, and is a term widely used in the technical field related to pressure-sensitive adhesives). Is suitable. At less than 20% of the pot life, the silicone resin is not yet fully cured, so if the barrier film is seated immediately in this state, the weight of the barrier film may affect the thickness of the surface printing layer and Difficult to settle down In addition, when 50% of the pot life is exceeded, since the silicone resin is hardened to some extent, the barrier film and the surface printed layer may not be integrated, and the uniformity of the surface printed layer may be adversely affected.

The total thickness of the surface printing layer (ie, the sum of the thicknesses of the two surface printing layers divided by the barrier layer) is not limited to this, but is preferably 0.01 to 1.2 mm, more preferably 0.1 to 1 mm. In order to form the thickness of the surface printed layer below this range, the application amount of the liquid silicone resin must be made in a very small amount, so that the leveling property may be lowered and the uniformity of the surface printed layer thickness may be impaired. Moreover, when thickness exceeds this range, there exists a possibility that the effect of adjusting the pressure by a cushion layer may not fully be acquired.

The printing blanket of the present invention may further include a slip coating layer in addition to the surface printing layer, the support layer, and the cushion layer. The slip coating layer serves to alleviate the stickiness of the cushion layer so that the printing blanket is well mounted on a roll or the like. In addition, the slip coating layer should not only be sticky, but also have the appropriate roughness necessary for mounting.

 The slip layer may be formed by coating a slip coating liquid on the cushion layer. The slip coating liquid may be prepared by appropriately mixing silicone resin, silicone oil, siloxane substituted terminal hydrogen, silica particles and the like. The slip coating liquid may be coated by a mayer bar or a baker applicator.

It is preferable that the total thickness of the printing blanket which has each said layer is 0.7-3 mm, and it is more preferable that it is 0.9-2 mm. When the thickness of the printing blanket is less than this range, the effect of adjusting the pressure of the printing blanket may be lowered. In the range exceeding this range, the thickness of the blanket may be too large, making it difficult to wind the blanket onto the roll.

A primer layer may be formed between the substrate and the layers to increase adhesion and integrity between the substrate and the layers. The primer layer can be formed to any thickness, without limitation, for purposes. As the material of the primer layer, one containing a silane coupling agent having good affinity with silicone resin can be used. In the case of forming the cushion layer and the surface printing layer without the primer layer, the surface of the substrate is physically or chemically treated to give affinity for the silicone resin and to apply the mixture to one side of the substrate to secure the adhesion to the substrate. desirable.

Hereinafter, the present invention will be described in more detail with reference to Examples. Embodiments herein are for the purpose of describing the invention only, and are not intended to limit the scope of the invention.

Example

100 parts by weight of liquid silicone resin and 10 parts by weight of hollow microspheres (MFL80CA manufactured by Matsumoto Oil & Fat Co., Ltd.) were added, and after mixing and uniformly dispersing the mixture, 10 parts by weight of a curing agent was further added to prepare a cushioning layer-forming mixture.

Next, a tensile force was applied to the polyethylene terephthalate (PET) substrate film having a thickness of about 0.35 mm on the surface plate, which was kept horizontal, in such a manner as to pull both ends, and then completely adhered to the surface plate.

Thereafter, the cushion layer forming mixture was evenly applied to one surface of the substrate surface using an applicator in an area of about 120 cm × 150 cm. This was cured at room temperature (23 ± 3 ° C.) for about 3 days to form a cushion layer having a thickness of 0.7 mm.

Next, while keeping the base film in close contact with the surface of the surface plate, a silicone resin containing silica was applied to the surface of the cushion layer using a mayer bar, dried at room temperature for about 24 hours, and then about 5 μm. A slip coating layer of thickness was formed.

Subsequently, the base film was inverted and one side of the opposite side of the base film was placed upward, and then a tensile force was applied to the base film by the same method as described above, and then completely adhered to the surface plate.

100 parts by weight of the liquid silicone resin and 10 parts by weight of the curing agent were mixed and uniformly dispersed to prepare a surface printed layer-forming mixture.

Thereafter, the surface printing layer-forming mixture was evenly applied to the remaining surface of the substrate surface using an applicator in an area of about 120 cm × 150 cm. At this time, the coating thickness of the mixture was about 0.35 mm.

When the applied composition was leveled by gravity, a PET film (film thickness was about 12 μm) was placed thereon, and the surface printing layer-forming mixture was applied on the PET material film again. At this time, the thickness of the mixture applied on the PET material film was about 0.35 mm.

Thereafter, curing was performed at room temperature (23 ± 3 ° C.) for about 3 days to form a surface printed layer, and finally, a printed blanket was completed.

Comparative example

100 parts by weight of liquid silicone resin and 10 parts by weight of hollow microspheres (MFL80CA manufactured by Matsumoto Oil & Fat Co., Ltd.) were added, and after mixing and uniformly dispersing the mixture, 10 parts by weight of a curing agent was further added to prepare a cushioning layer-forming mixture.

Next, a tensile force was applied to the polyethylene terephthalate (PET) substrate film having a thickness of about 0.35 mm on the surface plate maintained in a horizontal manner, and then the tensile force was applied to the surface plate.

Thereafter, the cushion layer forming mixture was evenly applied to one surface of the substrate surface using an applicator in an area of about 120 cm × 150 cm. This was cured at room temperature (23 ± 3 ° C.) for about 3 days to form a cushion layer having a thickness of 0.7 mm.

Next, while keeping the base film in close contact with the surface of the surface plate, a silicone resin containing silica was applied to the surface of the cushion layer using a mayer bar, dried at room temperature for about 24 hours, and then about 5 μm. A slip coating layer of thickness was formed.

Subsequently, the base film was inverted and one side of the opposite side of the base film was placed upward, and then a tensile force was applied to the base film by the same method as described above, and then completely adhered to the surface plate.

100 parts by weight of the liquid silicone resin and 10 parts by weight of the curing agent were mixed and uniformly dispersed to prepare a surface printed layer-forming mixture.

Thereafter, the surface printing layer-forming mixture was evenly applied to the remaining surface of the substrate surface using an applicator in an area of about 120 cm × 150 cm. At this time, the coating thickness of the mixture was about 0.7 mm.

Thereafter, curing was performed at room temperature (23 ± 3 ° C.) for about 3 days to form a surface printed layer, and finally, a printed blanket was completed.

Experimental Example  [Swelling Measurement Experiment]

Experiments for measuring the degree of swelling for the blanket produced in the Examples and Comparative Examples were carried out as follows.

In order to measure the degree of swelling, after swelling the blanket completely in methanol, the weight per unit time was measured while drying, and the result was as shown in FIG. 3 (swelling degree is expressed as the weight ratio of methanol absorbed).

As shown in FIG. 3, the degree of swelling of the examples was smaller from the beginning than in the comparative example (that is, the amount of solvent saturated from the initial example compared to the comparative example was less). In addition, it can be seen that less deswelling time compared to a certain reference amount.

This result, unlike the comparative example, it can be seen that the barrier layer provided in the Example inhibited the excessive solvent absorption of the surface printing layer to suppress the degree of swelling.

1 is a structural cross-sectional view of a conventional blanket used for reverse offset printing.

2 is a structural cross-sectional view of the printing blanket of the present invention.

3 is a graph showing the results of measuring the swelling degree of Examples and Comparative Examples.

Claims (6)

An offset printing blanket comprising a surface printing layer, a support layer, and a cushion layer, the offset printing blanket further comprising a barrier layer for preventing absorption of the solvent between the surface printing layers. The blanket of claim 1 wherein the barrier layer is formed of one or more materials selected from polyethylene terephthalate, polyethylene, and polypropylene. The blanket for offset printing of claim 1, wherein the barrier layer has a thickness in the range of 5 to 15 µm. The blanket for offset printing according to claim 1, wherein the barrier layer is formed at a position dividing the thickness of the surface printed layer into 1: 1 to 1.5. The blanket for offset printing according to claim 1, wherein the printed layer has a sum of thicknesses of two layers bisected by the barrier layer within a range of 10 to 1200 µm. In the manufacturing method of the blanket for offset printing containing the surface printing layer, the support layer, the cushion layer, and the barrier layer which prevents absorption of a solvent between the said surface printing layers, The barrier layer, Applying a silicone resin to a predetermined thickness; And It is formed by incorporating a surface printing layer comprising the step of depositing a film on the silicone resin, The step of seating the film on the silicone resin, the manufacturing method of the blanket for offset printing, characterized in that made in the range of 20 to 50% of the pot life of the silicone resin.

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