KR20110020163A - Printing method and solvent absorber used therefor - Google Patents

Abstract

PURPOSE: A printing method and a solvent absorber for the same are provided to prevent the insufficiency of silicon oil on the surface of a silicon blanket regardless of the repetition of a solvent absorbing process. CONSTITUTION: A solvent absorber is in contact with the surface of a silicon blanket. Solvent is contained in ink. The solvent is impregnated in the silicon blanket. The solvent is absorbed by the solvent absorber. The solvent absorber is formed based on a composition containing silicon rubber or a silicon resin, and dimethyl silicon oil. The dimethyl silicon oil is 3 or more and 50 or less parts by weight per, with respect to 100 parts by weight of the silicon rubber or the silicon resin.

Description

Printing method and solvent absorber used for it {PRINTING METHOD AND SOLVENT ABSORBER USED THEREFOR}

The present invention includes a printing method for printing a predetermined pattern made of the ink on the surface by transferring the ink supported on the surface of the silicon blanket to the surface of the printed object, and in the printing method, the ink is included in the ink, A solvent absorber used to absorb and remove a solvent impregnated in the silicone blanket.

The offset printing method has the advantage of being able to form ink patterns easily and efficiently in large quantities and inexpensively with a small number of steps, and in recent years, the printing accuracy has been improved, particularly in the field of electronics. Usage is expanding.

For example, in the field where the formation of fine and high precision patterns such as patterns of electric wiring, patterns of phosphors, or various patterns in components of a plasma display panel (PDP) or a liquid crystal display panel (LCD) is required, Instead of the pattern formation by the photolithography method, the offset printing method has been popularized.

In the offset printing method, a predetermined pattern is printed on the surface of the substrate by transferring the ink having a pattern formed on the surface of the plate to the surface of the blanket and then retransferring to the surface of the substrate as a printed object.

As a blanket, the silicone blanket which formed at least the surface by the silicone rubber or silicone resin which was excellent in the releasability to ink is widely used.

Since the silicone blanket is repeatedly in contact with the ink, especially when the printed material is made of a material which does not absorb a solvent such as a glass substrate, the solvent contained in the ink is impregnated during printing repeatedly to swell the silicone blanket gradually. Therefore, the wettability of the surface of the silicone blanket with respect to the ink gradually rises. Therefore, it is difficult to keep the printing precision at a high level for a long time from the beginning of printing.

When using an ink containing a low wettability solvent which hardly swells a silicone rubber or silicone resin, it is thought that stable printing can be performed since the wettability hardly changes even if the printing is repeated. However, since the ink containing the solvent with low wettability has low transferability from the surface of a board to the surface of a silicon blanket, disconnection tends to arise especially in the pattern of a thin wire | line.

Disconnection is the most unavoidable defect, and in order to prevent it, a solvent capable of swelling the silicon blanket to some extent should be used. By the way, when printing is repeated using the ink containing the said solvent, a silicone blanket will swell gradually, the wettability with respect to ink will rise gradually, and releasability will fall gradually. As the wettability increases, the ink easily spreads, and in particular, the line width of the thin line pattern gradually widens, transfers minute contamination on the surface of the plate, or decreases the releasability, thereby transferring the ink from the silicon blanket to the substrate. The performance is gradually lowered, and the accuracy of printing is gradually lowered.

It is conceivable to heat the silicone blanket to remove the swollen solvent. However, for this purpose, the silicon blanket must be heated to about 40 to 200 ° C., and when the silicon blanket having a high surface temperature immediately after heating is brought into contact with the plate, there is a problem that the plate is thermally expanded and the accuracy of printing is lowered.

It is proposed to contact the surface of a silicone blanket with a solvent absorber which has a function which absorbs a solvent, and to move the solvent impregnated in the said silicone blanket to a solvent absorber, and to remove it (refer patent document 1-4 etc.). According to this method, since a solvent can be removed without heating a silicon blanket, printing precision can be maintained at a high level. The removal of the solvent by the solvent absorber is performed every one to several times of printing.

Patent Document 1: Japanese Patent Application Laid-Open No. 2000-158620 Patent Document 2: Japanese Patent Laid-Open No. 2000-158633 Patent Document 3: Japanese Patent Laid-Open No. 2006-35769 Patent Document 4: Japanese Patent Application Laid-Open No. 2006-188015

The silicone blanket contains a low molecular weight silicone oil generated when the silicone rubber or silicone resin is crosslinked, and in a typical silicone blanket, the silicone oil generates so-called bleeding, which gradually spreads to the surface, thereby forming Good release property is imparted to the ink, and bleeding continuously occurs, whereby the good release property is maintained from the beginning of printing to the long term.

However, when the process of removing a solvent using a solvent absorber is carried out, the silicone oil which spread to the surface of a silicone blanket may also be absorbed by the said solvent absorber with a solvent, and may be removed from the surface of a silicone blanket.

Therefore, when repeating the solvent absorption process using the solvent absorber as described above, even if the swelling of the silicone blanket by the solvent can be suppressed, for example, due to the lack of silicone oil, the ink on the surface of the silicone blanket There exists a possibility that a releasability may fall and a transcription | transfer defect etc. may become easy to occur rather.

The object of the present invention is to prevent the silicone oil on the surface of the silicone blanket from running short even after repeating the solvent absorption process, and to suppress the swelling of the silicone blanket caused by the solvent absorption, and to provide a favorable ink on the surface. It is to provide a printing method which can maintain the accuracy of printing at a high level for a long time from the beginning of printing, while maintaining mold release property and preventing transfer defects and the like, and a solvent absorber used in the printing method.

The printing method of this invention transfers the ink which supported at least the surface of the said silicon blanket formed from the silicone rubber or the silicone resin to the surface of the to-be-printed body, and prints the pattern which consists of said ink on the surface of the to-be-printed body. And a step of contacting a surface of the silicon blanket with a solvent absorber to absorb the solvent contained in the ink and impregnated in the silicon blanket with the solvent absorber, wherein the solvent absorber includes at least the silicon. The surface (surface) which contacts the surface of a blanket is 3 mass parts or more and 50 mass parts or less per 100 mass parts of said silicone rubber or silicone resin, and a kinematic viscosity is 1 mm <2> / s or more , Formed by a composition containing dimethylsilicone oil of 5000 mm 2 / s or less It is a printing method.

According to the present invention, the dimethylsilicone oil contained on at least the surface of the solvent absorber functions to suppress the absorption of the silicone oil bleeded onto the surface of the silicone blanket by the solvent absorber. In addition, the dimethylsilicone oil, on the contrary, moves from the solvent absorber to the surface of the silicone blanket and also serves to compensate for the lack of silicone oil on the surface. Therefore, even if the process of solvent absorption by a solvent absorber is repeated, it can prevent that the silicone oil on the surface of a silicone blanket runs short by this action by dimethyl silicone oil.

Furthermore, according to the present invention, since at least the surface of the solvent absorber is formed of the same kind of silicone rubber or silicone resin (hereinafter, collectively referred to as "silicone rubber" or the like) as the surface of the silicone blanket to be combined, The adhesion of the surface of the solvent absorber to the surface of the silicon blanket can be improved, and both surfaces can be brought into close contact with each other without gaps in the process of solvent absorption. Therefore, absorption of the solvent from the silicone blanket to the solvent absorber and, conversely, diffusion of dimethylsilicone oil from the solvent absorber to the silicone blanket can be performed more smoothly.

Therefore, according to the printing method of the present invention, the ink on the surface is prevented, in addition to the effect of preventing the silicone oil on the surface of the silicone blanket from running short even after repeating the solvent absorption process, and suppressing the swelling of the silicone blanket caused by the solvent absorption. It is possible to keep the printing accuracy at a high level for a long time from the beginning of printing, while maintaining good mold release property and preventing transfer defects from occurring.

In the present invention, the kinematic viscosity of dimethylsilicone oil is limited to 1 mm 2 / s or more and 5000 mm 2 / s or less for the following reasons.

In other words, dimethylsilicone oil having a low viscosity having a kinematic viscosity of less than the above range has high volatility, and therefore is easily volatilized and lost from the surface of the solvent absorber or the silicone blanket. As a result, the silicone oil is insufficient, and the release property of the surface of the silicone blanket with respect to the ink gradually decreases. As a result, transfer failure or the like tends to occur, and the accuracy of printing decreases.

In addition, since dimethyl silicone oil having a high viscosity exceeding the above-mentioned range has low compatibility with silicone rubber constituting the surface of the solvent absorber, the dimethylsilicone oil is not uniformly dispersed in the silicone rubber or the like, so that it is biased in its distribution. Nonuniformity is easy to occur. Therefore, the effect of absorbing a solvent by the solvent absorber which contains dimethyl silicone oil at least in the surface, the effect which suppresses absorption of a silicone oil from the surface of a silicone blanket, and the dimethylsilicone oil which replenishes the surface of the said silicone blanket Effect also tends to be biased and uneven, and this nonuniformity tends to reduce the releasability to the ink on the surface of the silicon blanket or to swell the silicon blanket.

As the wettability increases, ink easily spreads, in particular, the line width of the thin line pattern gradually widens, transfers minute contamination on the surface of the plate, or decreases in releasability, and thus transferability of the ink from the silicon blanket to the substrate is reduced. This gradually lowers or lowers the accuracy of printing.

Therefore, in any of the above cases, it is not possible to obtain the effect of maintaining a high level of printing accuracy at a high level for a long time from the beginning of printing, while maintaining good mold release property with respect to the ink on the surface of the silicon blanket and preventing transfer defects from occurring. .

Moreover, in this invention, the content rate of dimethyl silicone oil is limited to 3 mass parts or more and 50 mass parts or less per 100 mass parts, such as a silicone rubber which comprises the surface of a solvent absorber, for the following reasons.

That is, if the content ratio is less than the above range, the above-described effect by containing dimethylsilicone oil on the surface of the solvent absorber cannot be obtained, and the silicone oil is insufficient while repeating the process of solvent absorption, and the ink on the surface of the silicone blanket As a result, the release property with respect to the film | membrane gradually declines, transfer defects etc. generate | occur | produce easily, and the precision of printing falls.

In addition, even if the content ratio exceeds the above range, no further effect can be obtained, the solvent absorber becomes too soft and the adhesion and adhesion to the surface of the silicone blanket become excessively strong, and from the surface of the silicone blanket after the step of solvent absorption. When removing, the solvent absorber which breaks the said solvent absorber, for example, which consists of a base material and an absorption layer mentioned later is concerned about causing peeling from the base material of the said absorption layer.

In addition, the dimethylsilicone oil is excessively supplied from the solvent absorber to the surface of the silicon blanket, and ink easily spreads. In particular, the line width of the thin wire pattern is gradually widened, or a small amount of contamination on the surface of the plate is transferred, or from the silicon blanket to the substrate. The transferability of the ink gradually decreases or the accuracy of printing decreases.

The present invention is 3 parts by mass or more, 50 parts by mass or less per 100 parts by mass of the silicone rubber or the like formed on at least one surface of the substrate or the film or sheet-like substrate, the silicone rubber, the kinematic viscosity is 1 mm 2 / s or more, It is a solvent absorber characterized by including the absorption layer which consists of a composition containing dimethyl silicone oil of 5000 mm <2> / s or less.

According to the present invention, the absorbent layer comprising the dimethylsilicone oil formed on at least one side of the substrate while maintaining the strength of the entire solvent absorbent body by the film or sheet-like substrate and ensuring good handleability of the silicone blanket By contacting the surface, the solvent impregnated in the silicone blanket can be absorbed and removed as smoothly as possible while preventing the silicone oil on the surface of the silicone blanket from running out.

By forming the solvent absorber into a belt type (including an endless belt type), the solvent absorber can be applied as it is to an offset printing machine using a solvent absorber such as the conventional belt type. Therefore, the printing method of this invention can be implemented using the said conventional offset printing press, and it maintains favorable mold release property with respect to the ink of the surface of a silicone blanket, and prevents a transfer defect etc. from occurring in the long term from the beginning of printing. It is possible to keep the printing accuracy at a high level over time.

Advantageous Effects of Invention According to the present invention, even when the solvent absorption process is repeated, the silicone oil on the surface of the silicone blanket is prevented from running short, and the swelling of the silicone blanket due to the solvent absorption is suppressed, and the surface of the ink is satisfactory. It is possible to provide a printing method capable of maintaining a high level of printing accuracy at a high level for a long time from the beginning of printing, while maintaining mold release property and preventing transfer failure, etc., and a solvent absorber used in the printing method.

The present invention is a printing method of printing a pattern made of the ink on a surface of a printed object by transferring the ink on at least the surface of the silicon blanket formed on at least the surface of the silicone blanket by printing on the surface of the printed object. Contacting the surface of the silicon blanket with the solvent absorber, thereby absorbing and removing the solvent contained in the ink by the solvent absorber, wherein the solvent absorber includes at least the surface of the silicon blanket. The surface to be in contact with the silicone rubber is composed of a silicone rubber or the like and dimethylsilicone oil having a kinematic viscosity of at least 3 parts by mass and at most 50 parts by mass, and having a kinematic viscosity of at least 1 mm 2 / s and at most 5000 mm 2 / s. It is characterized by using the formed.

Moreover, the solvent absorber of this invention used for the said printing method of this invention is 3 mass parts or more and 50 mass per 100 mass parts, such as a silicone rubber etc. formed in the film-type or sheet | seat base material, the at least one surface of the said base material, and the said silicone rubber. It is characterized by including the absorption layer which is below a part and consists of a composition containing dimethyl silicone oil whose kinematic viscosity is 1 mm <2> / s or more and 5000 mm <2> / s or less.

As silicone rubber etc. which form the said absorption layer, it is preferable to show a liquid state or a paste form at the time of uncuring, for example.

The silicone rubber or the like exhibiting a liquid-to-paste shape can be cured by applying it onto a substrate to a predetermined thickness using, for example, a doctor knife, a bar coater, a roll coater, or the like, and then forming an absorbing layer. By the so-called self-leveling effect, the surface of the coating film serving as the base of the absorbing layer, that is, the surface of the absorbing layer after curing can be smoothed, and the thickness of the absorbing layer can be made uniform.

Therefore, the solvent absorber which is excellent in the smoothness of the surface which can adsorb | suck a solvent by making it adhere to a surface of a silicon blanket without a gap can be manufactured with favorable productivity, without going through a process such as grinding | polishing. It goes without saying that the surface of the absorber layer may be polished as necessary.

Moreover, a solvent absorber may manufacture by inject | pouring and hardening | curing the silicone rubber etc. which show the said liquid form-paste form in the mold which set the base material, and has a shaping surface corresponding to the surface shape of an absorption layer.

For example, the absorption layer which consists of two-part addition reaction type liquid silicone rubber etc. which consist of a main body and a hardening | curing agent as mentioned below, and contains dimethyl silicone oil, is one of the said main materials and hardening | curing agent, for example, A predetermined amount of dimethylsilicone oil is added to the subject and mixed, and then a curing agent is added and mixed again to prepare a liquid composition (coating solution, injection liquid, etc.) for the absorbing layer, and then using any of the above methods. It can be formed as.

In this invention, the absorption layer is formed with the same kind of silicone rubber etc. as the surface of the silicone blanket combined, in order to improve the adhesiveness to the surface of the silicone blanket of the surface of the said absorption layer. As a result, in the step of absorbing the solvent, both surfaces can be brought into close contact with each other without any gap, so that the absorption of the solvent from the silicone blanket to the solvent absorber and the diffusion of dimethylsilicone oil from the solvent absorber to the silicone blanket are all It can be made more smoothly.

As said silicone rubber, it is preferable that it is room temperature hardening type (RTV). The above-mentioned room temperature curing type silicone rubber can be cured at room temperature (5 to 35 ° C.) without being heated as its name, so that not only the process for producing a solvent absorber and the equipment for manufacturing can be simplified, but also by heating Since it does not undergo expansion and contraction during cooling, the accuracy of the thickness of the absorbent layer can be improved.

Moreover, as said silicone rubber, it is preferable that it is a two-component addition reaction type which consists of two components of a main body and a hardening | curing agent as mentioned above, and can harden the said both by addition reaction.

Since the said two-component addition reaction type silicone rubber etc. do not generate | occur | produce a by-product (water etc. by dehydration condensation reaction) at the time of a hardening reaction, it improves the dimensional precision of an absorption layer, and contains the bubble etc. based on the said by-product. It is possible to form a uniform absorbent layer that does not.

As liquid silicone rubber which is the said room temperature hardening type and a two-part addition type, For example, product number KE1600, KE1603, KE1606, KE1310ST, KE1300T, KE1314, KE1241, KE106, KE103, Momentive performance materials manufactured by Shin-Etsu Chemical Co., Ltd. The article numbers TSE3402, TSE3453, TSE3455T, TSE3457, and TSE3466 of manufacture are mentioned.

As the dimethylsilicone oil to be contained in the absorbent layer, among various dimethylsilicone oils having a dimethylpolysiloxane structure, those having a kinematic viscosity at a measurement temperature of 23 ± 3 ° C of 1 mm 2 / s or more and 5000 mm 2 / s or less are selected and used.

The kinematic viscosity of dimethylsilicone oil is limited to the above range for the following reasons.

In other words, dimethylsilicone oil having a low viscosity having a kinematic viscosity of less than 1 mm 2 / s has high volatility, and therefore is easily volatilized and lost in the absorption layer or from the surface of the silicone blanket. As a result, the silicone oil is insufficient, and the release property of the surface of the silicone blanket with respect to the ink gradually decreases. As a result, transfer failure or the like tends to occur, and the accuracy of printing decreases.

In addition, since dimethylsilicone oil having a high viscosity of more than 5000 mm 2 / s has a low compatibility with the silicone rubber constituting the absorbent layer, the dimethylsilicone oil is not uniformly dispersed in the absorbent layer made of the silicone rubber or the like and biased in its distribution. And nonuniformity are easy to occur. Therefore, the effect of absorbing the solvent by the absorber containing dimethylsilicone oil, the effect of suppressing the absorption of silicone oil from the surface of the silicone blanket, and the effect of dispersing dimethylsilicone oil on the surface of the silicone blanket Non-uniformity tends to occur, and this non-uniformity tends to reduce the release property with respect to the ink of the surface of a silicon blanket, or it is easy to swell the said silicon blanket.

As the wettability increases, ink easily spreads, in particular, the line width of the thin line pattern gradually widens, transfers minute contamination on the surface of the plate, or decreases in releasability, and thus transferability of the ink from the silicon blanket to the substrate is reduced. This gradually lowers or lowers the accuracy of printing.

Therefore, in any of the above cases, it is not possible to obtain the effect of maintaining a high level of printing accuracy at a high level for a long time from the beginning of printing, while maintaining good mold release property with respect to the ink on the surface of the silicon blanket and preventing transfer defects from occurring. .

It is preferable that the kinematic viscosity of the dimethylsilicone oil is 2 mm 2 / s or more even within the above ranges in consideration of achieving the above-described effects of the present invention more favorably while preventing the occurrence of the various problems. It is preferable that it is 3000 mm <2> / s or less.

In order to set the kinematic viscosity of the dimethylsilicone oil to any value within the above range, for example, one having a predetermined kinematic viscosity among various grades of dimethylsilicone oil is used, or kinematic viscosity is mixed by combining two or more kinds of dimethylsilicone oils. You can adjust it.

As mentioned above, the content rate of dimethylsilicone oil should be 3 mass parts or more and 50 mass parts or less per 100 mass parts, such as a silicone rubber.

The content ratio is limited to the above range because of the following reason.

In other words, if the content ratio is less than 3 parts by mass, the above-described effect by incorporating dimethylsilicone oil into the absorbent layer cannot be obtained, and the silicone oil is insufficient while repeating the solvent absorption process, and the mold release property against the ink on the surface of the silicone blanket As a result of this gradual drop, transfer failure or the like tends to occur, and the accuracy of printing decreases.

Moreover, even if the content ratio exceeds 50 parts by mass, not only the above effects are not obtained, but the solvent absorber becomes excessively soft, the adhesion to the surface of the silicone blanket and the adhesiveness become too strong, and the peeling from the substrate of the absorbent layer is caused. I'm concerned.

In addition, the dimethylsilicone oil is excessively supplied from the absorber layer to the surface of the silicon blanket, so that the ink is more likely to spread, and in particular, the line width of the fine wire pattern gradually widens, transfers minute contamination of the surface of the plate, or ink from the silicon blanket to the substrate. The transferability of is gradually lowered or the accuracy of printing is lowered.

The content ratio of dimethylsilicone oil is 5 per 100 parts by mass, such as silicone rubber, within the above ranges, considering that the above-described effects of the present invention are further exerted while preventing the occurrence of the various problems. It is preferable that it is more than mass part, and it is preferable that it is 30 mass parts or less.

In addition to the said silicone rubber and dimethyl silicone oil, the said absorption layer may further contain various additives, such as fillers, such as a silica and a calcium carbonate, a hardening accelerator, and a hardening retarder.

It is preferable that the thickness of the said absorbing layer is 0.05 mm or more, especially 0.4 mm or more, and it is preferable that it is 2 mm or less, especially 1 mm or less.

Since a thin absorbent layer having a thickness less than the above range cannot absorb a sufficient amount of solvent, the frequency of changing the solvent absorber or removing the solvent by heating is increased, and the tact time of printing is increased by that amount. There is a fear that the productivity of.

In addition, when the thickness exceeds the above range, the flexibility of the absorbent layer and the followability to the surface of the silicon blanket thereby deteriorate, for example, the surface of the silicon blanket used in a state of being wound around the outer side of the blanket body, for example. There is a fear that the solvent cannot be absorbed in such a state that the absorbent layer is in close contact with the gap as far as possible.

In addition, the weight of the absorbent layer is increased, so that the handleability at the time of contacting the surface of the silicon blanket as described above may be reduced, or the substrate may be easily broken or wrinkled at the time of handling.

The hardness of the absorbent layer is preferably equal to or less than the hardness of the surface of the silicon blanket in consideration of satisfactorily following the surface of the silicon blanket and contacting without gaps.

In order to make the hardness of the absorbent layer less than or equal to the hardness of the surface of the silicone blanket, for example, the silicone rubber constituting the absorbent layer or the like may be selected and used to have a hardness after curing equal to or less than the hardness of the surface of the silicone blanket. What is necessary is just to adjust the content rate of the dimethyl silicone oil which functions to soften an absorption layer within the said range. Thereby, the hardness of an absorbing layer can be made softer than the surface of a silicone blanket.

The specific range of the hardness of an absorbing layer should just be below the hardness of the surface of a silicone blanket as mentioned above, Although it does not specifically limit, For example, it is prescribed | regulated by Japanese Industrial Standard JIS K6253: 2006 "Vulcanization rubber and thermoplastic rubber-hardness method". It is preferable that it is about A5 / S or more, A50 / S or less, especially A10 / S or more, and about A30 / S or less, as shown by the type A durometer hardness.

Moreover, it is preferable that the surface of an absorbing layer is as smooth as possible in order to contact with the surface of a silicone blanket without a gap. However, since the absorbent layer is flexible as described above, even if it is not as flat as the surface of the silicon blanket, the absorbing layer can be brought into close contact with the surface sufficiently without a gap.

Although the specific range of the surface roughness of the said absorption layer is not specifically limited, Annex 1 of Japanese Industrial Standard JIS B0601: 2001 "Geometry characteristic specification (GPS)-surface property of a product: contour curve system-term, definition, and surface property parameter" of Japanese Industrial Standards. It is preferable that it is 0.01 micrometer or more and 5 micrometers or less, especially 0.05 micrometer or more and about 1 micrometer or less, as represented by the _ten- point average roughness Rz _JIS94 prescribed | regulated to.

As a base material, the film or sheet of various resins, a thin metal plate, etc. are mentioned. Among them, as the film or sheet of the resin, polyethylene terephthalate (PET), polyvinyl chloride, polyethylene, polypropylene, polystyrene and its copolymers, polyvinylidene chloride, polyvinyl alcohol, fluororesin, polycarbonate, cellulose acetate, A film made of a resin such as polyamide, polyimide, modified polyphenylene ether, polysulfone, polyarylate, polyether sulfone, polyether ether ketone, polyetherimide, polyphenylene sulfide, TPX polymer and polyparaxylene, or A sheet is mentioned.

Moreover, as a thin plate of metal, the thin plate which consists of metals, such as copper or its alloy, aluminum or its alloy, stainless steel, nickel, is preferable.

In particular, it is preferable not only to be easy to process into a film or sheet form having an arbitrary thickness and surface roughness, but also to use a film or sheet of PET having excellent dimensional stability as a substrate.

It is preferable that the thickness of a base material is 0.05 mm or more, especially 0.1 mm or more, and it is preferable that it is 0.35 mm or less, especially 0.25 mm or less.

If the thickness is less than the above range, the effect of maintaining the strength of the entire solvent absorber as the support of the absorbing layer as a support of the absorbing layer and ensuring good handleability cannot be sufficiently obtained, and thus the base may be easily broken or wrinkled during handling. There is also concern.

Moreover, when thickness exceeds the said range, the softness | flexibility as a whole solvent absorber and the followability to the surface of the silicone blanket by this fall, and are used, for example, the silicone blanket used in the state wound around the outer side of a blanket main body, etc. There exists a possibility that a solvent may not be absorbed in the state which contacted the said absorption layer to the surface of as much as possible without a gap.

In order to improve the adhesiveness of the said absorbing layer, the surface of the base material before forming an absorbing layer may be pre-processed, for example, a plasma process, a frame process, or may form arbitrary base layers.

An absorption layer may be formed in one side of a base material, and may be formed in both surfaces. The solvent absorber in which the absorption layer was formed on both surfaces is used after the one side absorption layer is used for absorption of a solvent, and can be reversed and the absorption layer of an opposite surface can be used for absorption of a solvent.

The said solvent absorber can be formed in arbitrary shapes according to the structure of the printing machine which enforces a printing method, etc., It is preferable to form especially a belt type (including an endless belt type). Thereby, it is applicable as it is to an offset printing machine using a conventional solvent absorber such as the belt type.

For example, the solvent absorption body is formed into a long belt shape, wound in a roll shape, and the operation of absorbing the solvent by bringing a region of a predetermined length of the solvent absorber released from the roll into contact with the surface of the silicon blanket is performed. It can be used once or several times, and each time the operation of said predetermined number of times is performed, a new area | region of a solvent absorber can be released from the said roll, and can be used for solvent absorption similarly.

Further, the solvent absorber is formed into an endless belt shape, and the solvent absorber is heated or removed to remove the absorbed solvent each time the operation of absorbing the solvent by contacting the surface of the silicon blanket while rotating the solvent absorber is performed. The solvent absorber can be used repeatedly for solvent absorption.

In any of the above cases, since the absorbent layer of the solvent absorber contains a predetermined amount of dimethylsilicone oil as described above, even if the solvent absorption process is repeated using the solvent absorber, the silicone oil on the surface of the silicone blanket is insufficient. In addition to the effect of preventing the swelling of the silicone blanket due to the absorption of the solvent, while maintaining good release property of the ink on the surface, preventing transfer defects and the like from occurring, It is possible to keep the precision at a high level.

The printing method of the present invention is, for example

(1) an offset printing method in which an ink patterned on a surface of a plate such as a concave plate or a flat plate is transferred onto a surface of a silicon blanket, and then retransmitted onto a surface of a substrate as a printed object,

(2) Applying ink to the entire surface of the surface of the silicon blanket and then contacting the recess plate, the ink in contact with the region other than the recess of the recess plate is selectively removed from the surface of the silicon blanket to pattern the ink layer on the surface After forming, the reverse printing method for transferring to the surface of the substrate,

(3) The printing method which draws an ink pattern directly on the surface of a silicon blanket, and then transfers to the surface of the said board | substrate.

It is applicable to various printing methods using a silicon blanket, such as the above.

In the above various printing methods, the solvent absorber can be absorbed and removed by the solvent absorber by contacting the surface of the silicon blanket with the solvent absorber in the middle of printing, using the solvent absorber. have. As a result, the printing accuracy can be maintained at a high level for a long time from the beginning of printing.

As the silicone blanket, various silicone blankets at least whose surface is formed of silicone rubber or the like can be used. Specifically, a silicone blanket including a film- or sheet-like substrate and a surface rubber layer made of a composition containing at least a silicone rubber or the like formed on one side of the substrate is preferable.

As silicone rubber which comprises the said surface rubber layer, liquid silicone rubber or silicone resin which shows a liquid state or a paste form at the time of uncuring is preferable. When the liquid silicone rubber or the like is coated on the substrate to have a predetermined thickness using a doctor knife, a bar coater, a roll coater, or the like, and cured to form a surface rubber layer, The surface of the surface rubber layer can be smoothed and the thickness can be made uniform. Therefore, the silicon blanket which has the surface rubber layer excellent in the surface smoothness suitable for forming a fine and highly accurate pattern on the surface of the board | substrate as a to-be-printed body can be manufactured with favorable productivity, without going through a process of grinding | polishing etc. It goes without saying that the surface of the surface rubber layer may be polished as necessary.

In addition, the silicone blanket may be produced by injecting and curing a silicone rubber or the like exhibiting the liquid or paste shape into a mold having a shaping surface corresponding to the surface shape of the surface rubber layer and in which a base material is set.

As said silicone rubber, it is preferable that it is room temperature hardening type (RTV) again. Since the above-mentioned room temperature curing type silicone rubber can be cured at room temperature without heating, it is possible not only to simplify the manufacturing process and equipment for manufacturing the silicon blanket, but also to undergo expansion and cooling by heating and shrinkage during cooling. The precision of the thickness of the surface rubber layer can be improved.

Moreover, it is preferable that it is a two-component addition reaction type which consists of two components, a main body and a hardening | curing agent, and which can harden the said both by addition reaction as said silicone rubber.

Since the side product addition reaction type silicone rubber or the like does not generate by-products (water due to dehydration condensation reaction) during the curing reaction, the dimensional accuracy of the surface rubber layer is improved, and the bubbles based on the by-products are produced. The uniform surface rubber layer which does not contain can be formed.

Examples of the above-mentioned liquid room temperature curing type and two-part addition liquid silicone rubber include, for example, the above mentioned Shin-Etsu Chemical Co., Ltd. product number KE1600, KE1603, KE1606, KE1310ST, KE1300T, KE1314, KE1241, KE106, KE103, and momentary performance. The article numbers TSE3402, TSE3453, TSE3455T, TSE3457, and TSE3466 by a material made by Material Corporation are mentioned.

It is preferable that the thickness of the surface rubber layer is about 0.1 mm or more and about 1 mm or less especially in the case of the silicon blanket for precision printing which especially requires the high printing precision of the PDP, LCD pattern, etc. which were mentioned above.

Examples of the substrate include films or sheets of the same resin as those used in the above-described solvent absorbers, thin plates of metals, and the like, and are particularly easy to process into films or sheets having any thickness and surface roughness, as well as dimensions. Preference is given to films or sheets of PET with excellent stability.

In the case of the said silicon blanket for precision printing, the thickness of a base material is 0.01 mm or more,

It is preferable that it is about 0.4 mm or less.

In order to improve the adhesiveness of the said surface rubber layer, the surface of the base material before forming a surface rubber layer may be pre-processed, for example, a plasma process, a frame process, or arbitrary base layers may be formed.

The hardness of the surface rubber layer is expressed by the type A durometer hardness defined in the above JIS K6253: 2006, and is preferably about A10 / S or more, A70 / S or less, particularly A20 / S or more and A60 / S or less.

Moreover, since the surface state of a silicon blanket affects the precision, so that an ink pattern becomes fine, it is preferable that it is as flat as possible. For example, the surface roughness of the silicon blanket for precision printing is defined in Annex 1 to JIS B0601: 2001 "Geometric Properties Specification (GPS)-Surface Properties: Contour Curve Method-Terms, Definitions, and Surface Properties Parameters" of the product. _Ten point average roughness Rz _It is represented by _JIS94 , and it is preferable that they are about 0.01 micrometer or more and about 1 micrometer or less.

(Example)

Preparation of the solvent absorber of the following example and the comparative example, the measurement of a characteristic, and the test were implemented in the environment of the temperature of 23 +/- 3 degreeC, and 55 +/- 5% of relative humidity except having specifically described.

&Lt; Example 1 >

Dimethyl silicone oil having a mass of 91 parts by mass of a liquid dimethylsilicone rubber having a room temperature curing type and a two-component addition reaction type having a Type A durometer hardness (according to JIS K6253: 2006) of A30 / S after curing) and a kinematic viscosity of 3000 mm 2 / s. 20 parts by mass were mixed.

Subsequently, 9 parts by mass of the curing agent of the liquid dimethylsilicone rubber was added to the mixture, followed by degassing to prepare a coating liquid for the absorbing layer, and using the bar coater on one side of a 0.25 mm thick PET film as the substrate. After the coating was applied, the mixture was left to stand at room temperature for 24 hours to cure. An absorbent layer having a thickness of 0.70 mm and a plane direction of a PET film having a length of 50 cm x 50 cm was formed to prepare a solvent absorber.

The content of dimethylsilicone oil per 100 parts by mass of the main ingredient of the dimethylsilicone rubber and the total amount of the curing agent in the absorbent layer of the solvent absorber was 20 parts by mass as evident in the blending ratio.

<Examples 2 and 3, Comparative Examples 1 to 4>

The amount of dimethylsilicone oil to be blended into the coating liquid was 0 parts by mass (Comparative Example 1), 1 part by mass (Comparative Example 2), 5 parts by mass (Example 2), 40 parts by mass (Example 3), 60 parts by mass. A solvent absorber was produced in the same manner as in Example 1 except that (Comparative Example 3) and 100 parts by mass (Comparative Example 4) were used.

The content ratio of the dimethylsilicone rubber per 100 parts by mass of the main ingredient of the dimethylsilicone rubber and the total amount of the curing agent in the absorbent layer of each solvent absorber is 0 parts by mass (Comparative Example 1) and 1 parts by mass (comparatively). Example 2), 5 mass parts (Example 2), 40 mass parts (Example 3), 60 mass parts (comparative example 3), and 100 mass parts (comparative example 4).

<Print characteristic test>

(Production of silicon blanket)

After mixing at room temperature 91 parts by mass of a liquid silicone rubber having a room temperature curing type and a two-component addition reaction type having a type A durometer hardness (according to JIS K6253: 2006) of A30 / S and 9 parts by mass of a curing agent, degassing the surface rubber layer. A coating liquid was prepared, and the coating liquid was applied to one side of a 0.25 mm thick PET film as a substrate using a bar coater, and then left standing at room temperature for 24 hours to cure, and then 0.70 mm thick and in the plane direction of the PET film. A silicone rubber was produced by forming a surface rubber layer having a dimension of 50 cm in length x 50 cm in width.

(Printing process)

The said silicone blanket was wound around the outer periphery of the blanket main body of the concave-plate offset printing machine (The flat type precision printing machine compatible with 300 mm x 400 mm by Nakan Corporation). Moreover, what formed the patterned recessed part of the line width of 20 micrometers, the pitch of 300 micrometers, and the depth of 8 micrometers in the grid | lattice form on the surface of a glass plate was used.

As ink, the thing which knead | mixed and prepared the polyester resin, the butyl carbitol acetate as a solvent, and silver powder using three rolls was used.

Further, any one of the solvent absorbers prepared in each of the above examples and the comparative example is connected to each other to form an endless belt, and the solvent is brought into contact with each other while synchronously rotating with a silicone blanket wound around the outer side of the blanket body. It set so that the process of absorption may be performed. The feed rate of the endless belt at the time of synchronous rotation was set to 40 mm / s. The process of solvent absorption was performed every time printing was performed.

The printing condition is that the transfer speed of the ink from the concave plate to the silicon blanket is set to 100 mm / s, and the transfer speed of the ink from the silicon blanket to the surface of the glass substrate as a printed object is set to 100 mm / s. 50 consecutive prints were made while exchanging.

And the pattern printed on the surface of the glass substrate of the 50th printing was observed, and the printing adequacy was evaluated based on the following reference | standard.

(Double-circle): The state of a pattern was favorable almost unchanged with the printing 1st time.

(Circle): The state of a pattern fell slightly compared with the printing 1st time, but was in the tolerable range.

X: The state of a pattern was too bad, and it was not the level which can be used as a product.

The above results are shown in Table 1.

In Table 1, if the amount of dimethylsilicone oil to be contained in the absorber layer of the solvent absorber is less than 3 parts by mass per 100 parts by mass of silicone rubber, the above-described effect by incorporating dimethylsilicone in the solvent absorber cannot be obtained. It can be seen that, while the process is repeated, the silicone oil is deficient and the releasability to the ink on the surface of the silicone blanket is gradually lowered, resulting in poor transfer and the like, and the state of the pattern printed on the surface of the glass substrate is deteriorated. have.

In addition, when the amount of the dimethylsilicone oil exceeds 50 parts by mass, the dimethylsilicone oil is excessively supplied from the solvent absorber to the surface of the silicone blanket, so that the ink easily spreads, and in particular, the line width of the thin wire pattern gradually widens, or the plate surface. It was found that the microfouling of the particles was transferred, or the transferability of the ink from the silicon blanket to the substrate gradually decreased, and the state of the pattern printed on the surface of the glass substrate deteriorated.

On the other hand, by setting the amount of dimethylsilicone oil contained in the absorbent layer to 3 parts by mass or more and 50 parts by mass or less per 100 parts by mass of silicone rubber, the silicone oil on the surface of the silicone blanket is insufficient even if the solvent absorption process is repeated. And the effect of suppressing swelling of the silicone blanket due to the solvent absorption, and maintaining a good release property with respect to the ink on the surface to prevent the occurrence of transfer failure, etc. It was confirmed that a good pattern can be formed on the surface.

<Examples 4-6, Comparative Examples 5, 6>

As dimethylsilicone oil to be blended into the coating liquid, the kinematic viscosity is 0.05 mm 2 / s (Comparative Example 5), 1 mm 2 / s (Example 4), 20 mm 2 / s (Example 5), 5000 mm 2 / s (Example 6 ) And a solvent absorber were produced in the same manner as in Example 1, except that there was used) and 10000 mm 2 / s (Comparative Example 6).

In the absorption layer of each said solvent absorber, the content rate of the dimethylsilicone oil per main component of dimethylsilicone rubber and 100 mass parts of hardening | curing agents in total was 20 mass parts.

The said printing characteristic test was done using the solvent absorber manufactured by said each Example and the comparative example. The results are shown in Table 2 in combination with the results of Example 1.

In Table 2, when the kinematic viscosity of the dimethylsilicone oil contained in the absorbent layer of the solvent absorber is less than 1 mm 2 / s, since the dimethylsilicone oil is easily volatilized and lost from the surface of the silicone absorbent or the silicone blanket, the solvent absorption process is repeated. As a result, the silicone oil was deficient and the release property to the ink on the surface of the silicone blanket gradually decreased, and as a result, transfer defects tended to occur, and it was found that the state of the pattern printed on the surface of the glass substrate deteriorated.

When the kinematic viscosity of the dimethylsilicone oil exceeds 5000 mm 2 / s, since the dimethylsilicone oil is not uniformly dispersed in the solvent absorber and is likely to be biased or uneven in its distribution, such unevenness causes silicone It turned out that the releasability to the ink of the surface of a blanket falls, or that the said silicon blanket becomes easy to swell, and the state of the pattern printed on the surface of a glass substrate deteriorates.

On the other hand, by setting the kinematic viscosity of the dimethylsilicone oil contained in the absorbent layer to 1 mm 2 / s or more and 5000 mm 2 / s or less, the silicone oil on the surface of the silicone blanket is prevented from running short even if the solvent absorption process is repeated. In addition to the effect of suppressing the swelling of the silicon blanket due to solvent absorption, a good pattern on the surface of the glass substrate from the beginning of printing to a long period of time, while maintaining good release property to the ink on the surface and preventing transfer defects from occurring. It was confirmed that it can be formed.

Claims (3)

A printing method of printing a pattern made of the ink on a surface of the printed object by transferring the ink on at least the surface of the silicone blanket formed of a silicone rubber or a silicone resin onto the surface of the printed object, wherein the silicon Contacting the surface of the blanket with a solvent absorber, thereby absorbing and removing a solvent contained in the ink and impregnated in the silicon blanket with the solvent absorber, wherein the solvent absorber is formed on at least the surface of the silicon blanket. Dimethyl dimethyl silicone rubber or silicone resin with 3 parts by mass or more and 50 parts by mass or less per dynamic mass of 1 mm 2 / s or more and 5000 mm 2 / s or less per 100 parts by mass of the silicone rubber or silicone resin. Printing formed using the composition containing a silicone oil Law. A film-like or sheet-like substrate, a silicone rubber or silicone resin formed on at least one surface of the substrate, 3 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the silicone rubber or silicone resin, and has a kinematic viscosity of 1 A solvent absorber comprising an absorbent layer comprising a composition comprising dimethylsilicone oil of not less than 2 mm 2 / s and not more than 5000 mm 2 / s. The solvent absorber of Claim 2 formed in a belt form.