JP2017075315A - Ink remover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink remover that has excellent ink removability, hardly damages a rubber layer such as a resin layer and a silicone layer such as a thermosensitive layer and a photosensitive layer of a printing plate, and suppresses decrease in ink resilience.SOLUTION: An ink remover is used for printing with ink and comprises at least a compound represented by general formula (I) (where Rand Rare a C1-C4 saturated or unsaturated hydrocarbon group and may be linear or branched, and may be the same or different. Ris a C2-C6 saturated or unsaturated hydrocarbon group and may be linear, branched or cyclic).SELECTED DRAWING: None

Description

  The present invention relates to an ink remover used for printing with ink.

  There are various types of printing such as letterpress printing, intaglio printing, stencil (screen) printing, and lithographic printing, and printing is performed taking advantage of the characteristics of each method.

  Various proposals have been made regarding inks used for various printing, such as oil-based inks, water-based inks, and active energy ray-curable inks. Among them, printing using an active energy ray-curable ink for the purpose of high-speed drying (curing) of printed materials has been spreading in recent years. Active energy ray-curable inks have advantages that conventional oil-based inks and water-based inks do not have the advantage that they can be printed on the back side and post-processed immediately because they are instantly cured by irradiation with active energy rays after being transferred to the printing medium. doing.

  As for printing plates used for printing, various proposals have been made so far, such as intaglio plates having inorganic materials such as metal and glass, flexographic plates having a rubber layer, stencil plates having a resin layer, letterpress plates and planographic plates. A printing plate having a rubber layer such as a layer and a resin layer such as a heat-sensitive layer or a photosensitive layer at the same time has been proposed (for example, see Patent Document 1). Furthermore, for the purpose of improving ink resilience, a printing plate containing a silicone oil in a silicone rubber layer has been proposed (for example, see Patent Document 2).

  On the other hand, various proposals have been made regarding an ink remover used for printing.

  For example, an ink remover including an ester compound or an alcohol ester compound having a specific structure has been proposed (see, for example, Patent Document 3). Furthermore, an ink remover containing an ether compound or an alcohol ether compound having a specific structure has been proposed (see, for example, Patent Documents 4 and 5).

JP 2000-272266 A (Claims) JP 2001-232959 A (Claims) JP-A-8-333529 (Claims) JP-A-8-283628 (Claims) JP-A-9-208869 (Claims)

  The ink remover containing an ester compound having a specific structure described in Patent Document 3 is excellent in the ability to remove active energy ray-curable ink and swells a rubber layer such as a silicone layer of the printing plate described in Patent Document 1. Since it is difficult to damage the silicone rubber layer when removing the ink, and when the silicone rubber layer contains an ink repelling component such as silicone oil as described in Patent Document 2, the ink repelling component is also removed when removing the ink. Is difficult to be extracted from the silicone rubber layer, and the ink repellency of the portion where the ink has been removed is unlikely to decrease.

  However, the resin layer such as the heat sensitive layer and the photosensitive layer of the printing plate tends to be damaged, and the resin layer such as the heat sensitive layer and the photosensitive layer that should remain originally may fall off from the plate surface, resulting in poor printing.

  Further, the ink remover containing the alcohol ester compound described in Patent Document 3 and the alcohol ether compound described in Patent Document 4 is more likely to damage the heat-sensitive layer and the resin layer such as the photosensitive layer, and should remain originally. A resin layer such as a heat-sensitive layer or a photosensitive layer may fall off from the plate surface and cause printing failure.

  On the other hand, the ink remover containing the ether compound described in Patent Documents 4 and 5 has little damage to the resin layer such as the heat-sensitive layer and the photosensitive layer, but has poor ink removability and poor printing due to insufficient ink removal. There was a case. Further, since the rubber layer such as the silicone layer of the printing plate is easily swollen, the silicone rubber layer is easily damaged when the ink is removed, and the ink attached to the scratch may be transferred to the printed matter. Furthermore, when the silicone rubber layer contains an ink repellent component such as silicone oil, the ink repellent component is easily extracted from the silicone rubber layer when the ink is removed, and the ink repellency of the portion where the ink has been removed is significantly reduced. There was a thing.

  Thus, with the ink removers proposed so far, ink removability, suppression of damage to resin layers such as heat-sensitive layers and photosensitive layers of printing plates and rubber layers such as silicone layers, suppression of reduction in ink resilience All of these could not be achieved at the same time.

  Therefore, the object of the present invention is to solve the problems of the prior art, have excellent ink removability, hardly damage a resin layer such as a heat sensitive layer and a photosensitive layer of a printing plate, and a rubber layer such as a silicone layer, And it is providing the ink removal agent by which the fall of ink resilience was suppressed.

  The present invention is an ink removing agent used for printing using ink, and includes at least a compound represented by the following general formula (I).

(In the formula, R ¹ and R ² represent a saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms, which may be linear or branched, and may be the same or different. R ³ represents a saturated or unsaturated hydrocarbon group having 2 to 6 carbon atoms, and may be linear, branched or cyclic.

  According to the present invention, an ink having excellent ink removability, hardly causing damage to a resin layer such as a heat-sensitive layer or a photosensitive layer of a printing plate, or a rubber layer such as a silicone layer, and suppressing a decrease in ink resilience. A remover is obtained.

  The present invention is an ink removing agent used for printing using ink, and includes at least a compound represented by the general formula (I).

  The ink removing agent of the present invention is sometimes referred to as a cleaning agent, a cleaning liquid, or a cleaner.

  In printing, an ink remover is used to remove ink adhering to a roller or a blanket of a printing press or a printing plate. Since the roller, blanket, and printing plate are made of different materials (metal, resin, rubber, etc.), they all have different polarities. If these materials (resin, rubber, etc.) and the polarity of the ink remover are close, that is, if the affinity is high, deformation or destruction due to swelling of the resin or rubber by the ink remover is likely to occur, causing printing defects. Sometimes. For this reason, it is preferable to select an ink remover having a polarity different from that of resin or rubber used for printing. Of these, the printing plate has different materials depending on the type of printing plate, such as intaglio plates with inorganic materials such as metal and glass, flexographic plates with rubber layers, stencil plates with resin layers, letterpress plates, and lithographic plates. It has been difficult to find an ink remover that hardly damages any material. In particular, in the case of a printing plate having a rubber layer such as a silicone layer and a resin layer such as a heat-sensitive layer or a photosensitive layer at the same time, it is composed of a low-polarity silicone rubber layer and a high-polarity heat-sensitive layer or photosensitive layer. It was more difficult to select an ink remover with little affinity for any layer and less damage. Furthermore, for the purpose of improving ink repellency, in the case of a printing plate having an ink repellency component in the silicone rubber layer, the ink repellency component is extracted when the ink is removed, and the ink repellency of the ink removal portion is significantly reduced. The conventional low-polarity ink remover cannot be used, and the selection of the ink remover has been extremely difficult.

  As described above, although the ink remover described in Patent Document 3 has less damage to a resin layer such as a heat-sensitive layer or a heat-sensitive layer than a conventionally known alcohol-based or alcohol ether-based ink remover, it is still sufficient. The resin layers such as the heat-sensitive layer and the photosensitive layer were susceptible to damage, not the level. Although Patent Document 3 also describes that a diester compound can be used as an ink remover, the structure is different from the diester compound represented by the general formula (I) of the present invention. The diester compound described in Patent Document 3 is a diester compound obtained from 1 mol of dicarboxylic acid and 2 mol of monoalcohol, whereas the diester compound represented by the general formula (I) of the present invention is 1 mol of diol compound. And a diester compound obtained from 2 mol of monocarboxylic acid. Although the diester compound described in Patent Document 3 and the diester compound represented by the general formula (I) of the present invention have an approximate molecular weight, the boiling point is also approximate, so that the drying property shows an approximate performance. The damage to the resin layer such as the heat sensitive layer and the photosensitive layer is greatly different. In particular, the damage to a resin layer such as a heat-sensitive layer or a photosensitive layer containing a phenol resin, which will be described later, is greatly different, and is represented by the general formula (I) of the present invention as compared with the case where the diester compound described in Patent Document 3 is used. When the diester compound to be used is used, damage to the resin layers such as the heat-sensitive layer and the photosensitive layer is greatly suppressed. Although the mechanism by which the damage to the resin layer such as the heat sensitive layer and the photosensitive layer is greatly different is not clear at present, it is considered that the difference in structure between the two diester compounds and the way of polarization are different.

  On the other hand, although the ink remover containing the ether compound described in Patent Documents 4 and 5 has low polarity, the resin layer such as the heat-sensitive layer and the photosensitive layer is less damaged, but the rubber layer such as the silicone layer is easily swollen. For this reason, the silicone rubber layer is easily damaged when the ink is removed, and the ink attached to the scratch may be transferred to the printed matter.

  In addition, when the silicone rubber layer includes an ink repellent component such as silicone oil as described in Patent Document 2, ink repelling is performed at the time of ink removal with the ether-based ink remover described in Patent Documents 4 and 5. Ingredients were easily extracted from the silicone rubber layer, and the ink repellency of the part where the ink was removed may be reduced.

  Therefore, the inventors proceeded with a search for an ink remover that is a highly polar compound but causes little damage to the resin layer such as the highly polar heat-sensitive layer and the photosensitive layer, and as a result of sincerity studies, the present invention was completed. It was. Specifically, by using a highly polar diester compound having a specific structure as an ink remover, the affinity for low polarity materials such as rubber layers such as silicone layers and ink repellent components contained in silicone rubber layers is low. It is possible to suppress the scratches that occur when the ink is removed from the silicone rubber layer and the extraction of ink repellent components from the silicone rubber layer, and the heat sensitive layer is made of a compound that has a molecular structure that is significantly different from the resin layer such as the heat sensitive layer and the photosensitive layer. Damage to resin layers such as layers and photosensitive layers can also be suppressed. That is, damage is caused to both low-polarity materials such as a silicone layer and other rubber layers and ink repulsion components contained in the silicone rubber layer, and high-polarity materials such as a heat-sensitive layer and a resin layer such as a photosensitive layer. An ink remover that is difficult to give and excellent in ink removability can be obtained.

  Hereinafter, an ink remover used for printing using the ink of the present invention and an ink removing method in printing will be described in detail.

  The ink remover of the present invention is effective for removing various inks such as oil-based inks, water-based inks, and active energy ray-curable inks, and is particularly effective for removing active energy ray-curable inks. That is, the ink is preferably an active energy ray curable ink. The active energy ray in the present invention refers to energy rays such as ultraviolet rays and electron beams, but is not limited thereto. Ultraviolet curable ink (hereinafter referred to as UV ink) and electron beam curable ink (hereinafter referred to as EB ink) transfer active energy rays in the presence or absence of an inert gas after transfer to a printing medium. Since it cures instantaneously by irradiation, it has the merit that printing on the back side and post-processing can be performed immediately.

  Examples of the active energy ray-curable ink that can be preferably used in the present invention include, but are not limited to, the inks described below.

<UV ink>
As UV ink, the well-known UV ink disclosed by patent 5158274, Unexamined-Japanese-Patent No. 2012-211230, etc. is mentioned, for example. The UV ink of the present invention also includes high-sensitivity UV ink used for power-saving (light-reduction) UV printing and Light Emitting Diode (hereinafter referred to as LED) -UV printing. UV inks are already sold by ink manufacturers and can be easily obtained.

<EB ink>
Examples of the EB ink include, for example, JP-A-57-0778468, JP-A-57-155270, JP-A-57-174363, JP-A-5-320555, JP-A-8-283529, JP-A-8-325500, JP-A-8-325501, JP-A-10-0877747, JP2001-158080, JP2004-161812, JP2004-359767, JP Publicly known EB inks disclosed in JP 2005-015755 A and the like can be mentioned.

  Further, generally known active energy ray curable varnishes used for the purpose of improving the gloss of the printed material surface (improving gloss or matte) are also within the category of the active energy ray curable ink of the present invention.

  Next, the ink remover will be described. The ink remover in the present invention is an ink remover used for printing using ink, and is an ink remover containing at least the compound represented by the general formula (I).

  Specific examples of the compound represented by the general formula (I) include ethylene glycol diacetate, ethylene glycol dipropionate, ethylene glycol dibutyrate, propylene glycol diacetate, propylene glycol dipropionate, propylene glycol dibutyrate, 1 , 3-propanediol diacetate, 1,3-propanediol dipropionate, 1,3-propanediol dibutyrate, 1,2-butanediol diacetate, 1,2-butanediol dipropionate, 1,2- Butanediol dibutyrate, 1,3-butanediol diacetate, 1,3-butanediol dipropionate, 1,3-butanediol dibutyrate, 1,4-butanediol diacetate, 1,4-butanediol dipropio 1,4-butanediol dibutyrate, 1,2-pentanediol diacetate, 1,2-pentanediol dipropionate, 1,2-pentanediol dibutyrate, 1,3-pentanediol diacetate, , 3-pentanediol dipropionate, 1,3-pentanediol dibutyrate, 1,4-pentanediol diacetate, 1,4-pentanediol dipropionate, 1,4-pentanediol dibutyrate, 1,5- Pentanediol diacetate, 1,5-pentanediol dipropionate, 1,5-pentanediol dibutyrate, 1,2-hexanediol diacetate, 1,2-hexanediol dipropionate, 1,2-hexanediol dibuty Rate, 1,3-hexanediol diacete 1,3-hexanediol dipropionate, 1,3-hexanediol dibutyrate, 1,4-hexanediol diacetate, 1,4-hexanediol dipropionate, 1,4-hexanediol dibutyrate, 1 , 5-hexanediol diacetate, 1,5-hexanediol dipropionate, 1,5-hexanediol dibutyrate, 1,6-hexanediol diacetate, 1,6-hexanediol dipropionate, 1,6- Hexanediol dibutyrate, 1,2-cyclohexanediol diacetate, 1,2-cyclohexanediol dipropionate, 1,2-cyclohexanediol dibutyrate, 1,3-cyclohexanediol diacetate, 1,3-cyclohexanediol dipropio Nate, 1,3-cyclohexanediol dibutyrate, 1,4-cyclohexanediol diacetate, 1,4-cyclohexanediol dipropionate, 1,4-cyclohexanediol dibutyrate, 1,2-dihydroxybenzene diacetate, 1,2- Dihydroxybenzene dipropionate, 1,2-dihydroxybenzene dibutyrate, 1,3-dihydroxybenzene diacetate, 1,3-dihydroxybenzene dipropionate, 1,3-dihydroxybenzene dibutyrate, 1,4-dihydroxybenzene di Acetate, 1,4-dihydroxybenzene dipropionate, 1,4-dihydroxybenzene dibutyrate, 1,2-dihydroxyethene diacetate, 1,2-dihydroxyethene dipropionate, 1,2-dihi Loxyethene dibutyrate, 1,2-dihydroxy-1-propene diacetate, 1,2-dihydroxy-1-propene dipropionate, 1,2-dihydroxy-1-propene dibutyrate, 1,3-dihydroxy-1- Propene diacetate, 1,3-dihydroxy-1-propene dipropionate, 1,3-dihydroxy-1-propene dibutyrate, 1,2-dihydroxy-1-butene diacetate, 1,2-dihydroxy-1-butene Dipropionate, 1,2-dihydroxy-1-butene dibutyrate, 1,3-dihydroxy-1-butene diacetate, 1,3-dihydroxy-1-butene dipropionate, 1,3-dihydroxy-1-butene Dibutyrate, 1,3-dihydroxy-2-butene diacetate, 1,3-dihy Roxy-2-butene dipropionate, 1,3-dihydroxy-2-butene dibutyrate, 1,4-dihydroxy-1-butene diacetate, 1,4-dihydroxy-1-butene dipropionate, 1,4- Dihydroxy-1-butene dibutyrate, 1,4-dihydroxy-2-butene diacetate, 1,4-dihydroxy-2-butene dipropionate, 1,4-dihydroxy-2-butene dibutyrate, 1,2-dihydroxy -1-pentene diacetate, 1,2-dihydroxy-1-pentene dipropionate, 1,2-dihydroxy-1-pentene dibutyrate, 1,3-dihydroxy-1-pentene diacetate, 1,3-dihydroxy- 1-pentene dipropionate, 1,3-dihydroxy-1-pentene dibutyrate, 1, 3-dihydroxy-2-pentene diacetate, 1,3-dihydroxy-2-pentene dipropionate, 1,3-dihydroxy-2-pentene dibutyrate, 1,4-dihydroxy-1-pentene diacetate, 1,4 -Dihydroxy-1-pentene dipropionate, 1,4-dihydroxy-1-pentene dibutyrate, 1,4-dihydroxy-2-pentene diacetate, 1,4-dihydroxy-2-pentene dipropionate, 1,4 -Dihydroxy-2-pentene dibutyrate, 1,4-dihydroxy-3-pentene diacetate, 1,4-dihydroxy-3-pentene dipropionate, 1,4-dihydroxy-3-pentene dibutyrate, 1,5- Dihydroxy-1-pentene diacetate, 1,5-dihydroxy-1-pen Dipropionate, 1,5-dihydroxy-1-pentene dibutyrate, 1,5-dihydroxy-2-pentene diacetate, 1,5-dihydroxy-2-pentene dipropionate, 1,5-dihydroxy-2- Pentene dibutyrate, 1,2-dihydroxy-1-hexene diacetate, 1,2-dihydroxy-1-hexene dipropionate, 1,2-dihydroxy-1-hexene dibutyrate, 1,3-dihydroxy-1-hexene Diacetate, 1,3-dihydroxy-1-hexene dipropionate, 1,3-dihydroxy-1-hexene dibutyrate, 1,3-dihydroxy-2-hexene diacetate, 1,3-dihydroxy-2-hexene dipro Pionate, 1,3-dihydroxy-2-hexene dibutyrate, 1, -Dihydroxy-1-hexene diacetate, 1,4-dihydroxy-1-hexene dipropionate, 1,4-dihydroxy-1-hexene dibutyrate, 1,4-dihydroxy-2-hexene diacetate, 1,4- Dihydroxy-2-hexene dipropionate, 1,4-dihydroxy-2-hexene dibutyrate, 1,4-dihydroxy-3-hexene diacetate, 1,4-dihydroxy-3-hexene dipropionate, 1,4- Dihydroxy-3-hexene dibutyrate, 1,5-dihydroxy-1-hexene diacetate, 1,5-dihydroxy-1-hexene dipropionate, 1,5-dihydroxy-1-hexene dibutyrate, 1,5-dihydroxy 2-hexene diacetate, 1,5-dihydroxy-2-hexe Dipropionate, 1,5-dihydroxy-2-hexene dibutyrate, 1,5-dihydroxy-3-hexene diacetate, 1,5-dihydroxy-3-hexene dipropionate, 1,5-dihydroxy-3- Hexene dibutyrate, 1,5-dihydroxy-4-hexene diacetate, 1,5-dihydroxy-4-hexene dipropionate, 1,5-dihydroxy-4-hexene dibutyrate, 1,6-dihydroxy-1-hexene Diacetate, 1,6-dihydroxy-1-hexene dipropionate, 1,6-dihydroxy-1-hexene dibutyrate, 1,6-dihydroxy-2-hexene diacetate, 1,6-dihydroxy-2-hexene dipro Pionate, 1,6-dihydroxy-2-hexene dibutyrate, 1,6 Dihydroxy-3-hexene diacetate, 1,6-dihydroxy-3-hexene dipropionate, 1,6-dihydroxy -3-hexene dibutyrate include, but are not limited to.

  Among these compounds, a compound having a boiling point of 240 ° C. or less is preferable, a compound having a boiling point of 200 ° C. or less is more preferable, and a compound having a temperature of 190 ° C. or less is more preferable in that it can be easily dried after ink removal and printing can be resumed immediately. Here, the boiling point in the present invention refers to the temperature (standard boiling point) at which the liquid begins to boil under 1 atm.

From the viewpoint of drying properties, it is preferable that R ^{3 of the} compound represented by the general formula (I) is a branched saturated hydrocarbon group having 3 to 6 carbon atoms.

Moreover, it is preferable that both R < ¹ > and R < ² > of the compound represented by the said general formula (I) are a methyl group from the point of suppressing damage to rubber layers, such as a silicone layer of a printing plate.

In the compound represented by the general formula (I), R ³ is a branched saturated hydrocarbon having 2 to 6 carbon atoms, and R ¹ and R ² are both methyl groups. It is more preferable because damage suppression to a rubber layer such as a silicone layer can be simultaneously achieved.

  In addition, when the melting point of the ink removing agent is high, it solidifies at room temperature and the workability is remarkably lowered. Therefore, the melting point is preferably 10 ° C. or lower, more preferably 0 ° C. or lower.

  In addition, if the flash point of the ink removing agent is low, the risk of ignition increases, so the flash point is preferably 21 ° C. or higher, more preferably 70 ° C. or higher.

  Furthermore, since the risk of various adverse effects on the human body and the environment increases when the harmfulness of the ink remover is high, a safer compound is preferable. Specifically, it is a compound that does not fall under the category of poisonous substances or deleterious substances under the Poisonous and Deleterious Substances Control Law, a compound that does not fall under the category of designated chemical substances under the Chemical Substances Emissions Control Management Promotion Law, and the organic solvent poisoning prevention regulations It is preferable that it is a compound which does not correspond to the organic solvent in.

  Of the above-mentioned compounds, an ink remover containing propylene glycol diacetate is more preferable in terms of achieving a balance between drying properties, workability, and safety. That is, in the present invention, the compound represented by the general formula (I) is preferably propylene glycol diacetate.

  In addition, each of the compounds represented by the general formula (I) may be used alone as an ink remover, or a plurality of types may be mixed and used.

  Furthermore, it is good also as a ink remover by mixing with compounds other than the compound represented by the said general formula (I). As a compound other than the compound represented by the general formula (I), it is excellent in ink removability, hardly damages a rubber layer such as a silicone layer of a printing plate, and has a photosensitive layer or a heat-sensitive layer of the printing plate. An ester compound is preferable in that it is relatively less likely to damage the resin layer (more easily damaged than the compound represented by the general formula (I)), and is obtained from 1 mol of dicarboxylic acid and 2 mol of monoalcohol. Diester compounds are more preferred. Diester compounds obtained from 1 mol of dicarboxylic acid and 2 mol of monoalcohol include dimethyl oxalate, diethyl oxalate, dimethyl malonate, diethyl malonate, dimethyl succinate, diethyl succinate, dimethyl fumarate, diethyl fumarate, malein Examples thereof include dimethyl acid and diethyl maleate.

  When the compound represented by the general formula (I) and other compounds are mixed to form an ink remover, the content of the compound represented by the general formula (I) in the ink remover is The weight is preferably 60% by weight or more, and more preferably 80% by weight or more from the viewpoint that damage to a resin layer such as a heat-sensitive layer or a photosensitive layer and a rubber layer such as a silicone layer can be suppressed. As described above, since the compound represented by the general formula (I) can be used alone as an ink remover, it may be 100% by weight.

  The above-mentioned active energy ray curable ink contains a large amount of (meth) acrylate compound monomers, oligomers, polymers, polyester compounds, etc. that have a high affinity with the ink remover of the present invention. Can be removed.

  On the other hand, since the ink removing agent of the present invention has no corrosiveness to metals, it can be suitably used for removing ink adhering to the surface of a metal used for each cylinder of a printing press or a roller of an ink supply unit. it can. Further, since the ink remover of the present invention has low affinity for various rubbers, the surface generally used in printing can also be used for removing ink adhered to the surface of a rubber roller or blanket. . Among them, Ethylene-Propylene-Diene Terpolymer (hereinafter referred to as EPDM) is a low polarity rubber and has extremely low affinity with the high polarity ink remover of the present invention. Therefore, EPDM is used as a main component of the surface rubber. In the case of the used roller or blanket, it is preferable in that the damage such as deformation during ink removal is small. Rollers and blankets using EPDM as the main component of the surface rubber are widely used all over the world in printing using ink.

  The ink remover of the present invention can also be suitably used for removing ink adhering to the surface of the printing plate. Among them, the present invention can be preferably applied to an embodiment in which the printing plate has a resin layer and / or a rubber layer. Particularly preferably, in the embodiment on the left side, the resin layer and / or the rubber layer of the printing plate is heat sensitive or It has photosensitivity.

  Examples of the printing plate include a printing plate having a resin layer such as a heat-sensitive layer or a photosensitive layer, and a resin layer such as a heat-sensitive layer or a photosensitive layer containing a large amount of an ester compound, a (meth) acrylate compound, or a polymer thereof. For the printing plate having, the ink remover of the present invention has a slightly higher affinity and a little damage, so there is no particular problem in a short time use, but a heat-sensitive layer that should remain after a long time use And a resin layer such as a photosensitive layer may fall off from the plate surface.

  On the other hand, the ink remover of the present invention has a low affinity for a phenol resin widely used as a base polymer for a resin layer such as a heat-sensitive layer or a photosensitive layer of a printing plate, and can be suitably used because of its small damage. . Therefore, in this invention, the aspect in which a resin layer contains a phenol resin at least is preferable. Examples of the phenol resin include novolak resins obtained from cresol, phenol and formaldehyde, resole resins, homopolymers and copolymers of parahydroxystyrene, and acetone pyrogallol resins.

  Examples of the heat-sensitive layer containing a phenol resin include, for example, JP-A-11-221977, JP-A-2005-309126, JP-A-2009-014946, JP-A-2005-300586, and JP-A-2005-331924. A heat-sensitive layer described in WO2010 / 113989A1, JP2012-93728A, JP2012-133321A, JP2012-133322A, WO2012 / 043282A1, WO2012 / 099003A1, and the like. Examples of the photosensitive layer containing a phenol resin include a photosensitive layer described in JP-A No. 11-352672.

  The ink removing agent of the present invention is also suitably used for removing ink adhering to a printing plate having a rubber layer such as a silicone layer (sometimes referred to as “ink repellent layer”). In the present invention, an embodiment in which the rubber layer is a silicone rubber layer is preferable. As the silicone rubber layer, a known addition reaction type silicone rubber layer or condensation reaction type silicone rubber layer can be used.

  Since the ink remover of the present invention is highly polar, it has a very low affinity with the low-polarity silicone rubber layer, and it is difficult to swell the silicone rubber layer. For this reason, it is hard to generate | occur | produce a damage | wound in a silicone rubber layer at the time of ink removal.

  First, an addition reaction type silicone rubber layer used for a printing plate in which the ink remover of the present invention can be suitably used will be described. Examples of the addition reaction type silicone rubber layer include, but are not limited to, the following addition reaction type silicone rubber layer.

  It is preferable to include at least a SiH group-containing compound, a compound represented by the following general formula (II), and a compound represented by the following general formula (III). Moreover, it is more preferable that a vinyl group containing silicone compound and a reaction catalyst are included, and a reaction inhibitor may be included.

(In the formula, A represents a functional group that undergoes a hydrosilylation reaction with a SiH group, and D represents a hydrolyzable group.)

(In the formula, E represents a functional group that does not undergo a hydrosilylation reaction with the SiH group, and G represents a hydrolyzable group.)

  Examples of the SiH group-containing compound include compounds having 3 or more SiH groups in one molecule. Examples include organohydropolysiloxanes, organohydrosiloxane / diorganosiloxane copolymers, and compounds having three or more diorganohydrosiloxy groups in the molecule. Of these, organohydropolysiloxane and organohydrosiloxane / diorganosiloxane copolymer are preferable. Two or more of these may be contained. The number of SiH groups in one molecule of the SiH group-containing compound is preferably 5 or more and more preferably 6 or more in order to improve the curability of the silicone rubber layer.

  Organohydropolysiloxanes and organohydrosiloxane / diorganosiloxane copolymers have a linear, cyclic, branched, and network molecular structure. Moreover, the organic group couple | bonded with the silicon atom may be same or different, and each shows the monovalent organic group which does not contain an aliphatic unsaturated bond. Examples of the monovalent organic group that does not contain an aliphatic unsaturated bond include methyl groups, ethyl groups, propyl groups, butyl groups, pentyl groups, hexyl groups, and heptyl groups; alkyl groups; phenyl groups, tolyl groups, xylyl groups, Aryl groups such as naphthyl group; aralkyl groups such as benzyl group and phenethyl group; halogenated alkyl groups such as chloromethyl group, 3-chloropropyl group and 3,3,3-trifluoropropyl group.

  The content of the SiH group-containing compound is preferably 0.5% by weight or more in the silicone rubber layer composition liquid for improving the curability of the silicone rubber layer, and more preferably 1% by weight or more. Moreover, 10 weight% or less is preferable when improving ink resilience, and 5 weight% or less is more preferable.

  The compound represented by the general formula (II) is a compound in which A is a functional group that undergoes a hydrosilylation reaction with a SiH group, and D is a hydrolyzable group. Examples of the functional group A that undergoes a hydrosilylation reaction with the SiH group include a vinyl group, an allyl group, and a (meth) acryloyl group. Among these, a vinyl group is preferable for improving the reactivity with the SiH group-containing compound and the ink resilience. Examples of the hydrolyzable group D include an alkoxy group, an enoxy group, a dialkyl ketoximino group, and an acetoxy group. Among them, a dialkyl ketoximino group and an acetoxy group are preferable for improving the reactivity with the lower layer, which is important for improving the adhesive strength with the lower layer. Specific examples of such a compound represented by the general formula (II) include, but are not limited to, vinyltriacetoxysilane and vinyltris (methylethylketoximino) silane. When the lower layer contains a phenolic hydroxyl group, it is particularly preferable to use a compound in which D is a dialkyl ketoximino group, and high adhesive strength can be obtained with a small amount of addition. In addition to high reactivity to the lower layer, the dialkyl ketoximino group easily forms a salt with the phenolic hydroxyl group, which is a weak acid, and therefore is represented by the general formula (II) to the silicone rubber layer / lower layer interface. This is probably because the concentration of the components of the compound is promoted.

  The content of the compound represented by the general formula (II) is preferably 0.5% by weight or more in the silicone rubber layer composition liquid in terms of improving adhesion to the lower layer. Moreover, 2 weight% or less in a silicone rubber layer composition liquid is preferable at the point which improves ink resilience, and 1.5 weight% or less is more preferable.

  The compound represented by the general formula (III) is a compound in which E is a functional group that does not undergo a hydrosilylation reaction with a SiH group, and G is a hydrolyzable group. Examples of the functional group E that does not undergo a hydrosilylation reaction with the SiH group include an alkyl group, a phenyl group, a 3-glycidoxypropyl group, and a 3-isocyanatopropyl group. Among these, an alkyl group or a phenyl group is preferable, and a phenyl group is more preferable in that the reactivity with the lower layer, which is important for improving the adhesive strength with the lower layer, is improved. Examples of the hydrolyzable group G include an alkoxy group, an enoxy group, a dialkyl ketoximino group, and an acetoxy group. Among them, a dialkyl ketoximino group and an acetoxy group are preferable for improving the reactivity with the lower layer, which is important for improving the adhesive strength with the lower layer. Specific examples of the compound represented by the general formula (III) include methyltriacetoxysilane, ethyltriacetoxysilane, phenyltriacetoxysilane, methyltris (methylethylketoximino) silane, and ethyltris (methylethylketoximino) silane. , Phenyltris (methylethylketoximino) silane, and the like, but are not limited thereto. When the lower layer contains a phenolic hydroxyl group, it is particularly preferable to use a compound in which G is a dialkyl ketoximino group, and high adhesive strength can be obtained with a small amount of addition. In addition to high reactivity with the lower layer, the dialkyl ketoximino group easily forms a salt with the phenolic hydroxyl group, which is a weak acid, and therefore is represented by the general formula (III) to the silicone rubber layer / lower layer interface. This is probably because the concentration of the components of the compound is promoted.

  The content of the compound represented by the general formula (III) is preferably 0.5% by weight or more in the silicone rubber layer composition solution in terms of improving adhesion to the lower layer. Moreover, 5.5 weight% or less in a silicone rubber layer composition liquid is preferable at the point which improves ink resilience, and 4.5 weight% or less is more preferable.

  The total of the weight percent of the compound represented by the general formula (II) and the weight percent of the compound represented by the general formula (III) is 2.5 in terms of achieving both adhesion to the lower layer and ink repellency. It is preferable to be within the range of ˜6% by weight.

  Examples of the vinyl group-containing silicone compound include compounds represented by the following general formula (IV), and are silicone compounds having two or more vinyl groups in the molecule. Among them, a compound having vinyl groups at both ends of the molecular main chain is preferable in terms of improving the curability of the silicone rubber layer. Moreover, you may contain 2 or more types of these.

  In the compound represented by the general formula (IV), T is a functional group represented by the following general formula (V).

In the compound represented by the general formula (IV) and the functional group represented by the general formula (V), R ⁴ represents either a vinyl group or a monovalent organic group not containing an aliphatic unsaturated bond. R ⁵ represents a monovalent organic group not containing an aliphatic unsaturated bond. Examples of the monovalent organic group that does not contain an aliphatic unsaturated bond include methyl groups, ethyl groups, propyl groups, butyl groups, pentyl groups, hexyl groups, and heptyl groups; alkyl groups; phenyl groups, tolyl groups, xylyl groups, Aryl groups such as naphthyl group; aralkyl groups such as benzyl group and phenethyl group; halogenated alkyl groups such as chloromethyl group, 3-chloropropyl group and 3,3,3-trifluoropropyl group. a represents an integer of 0 to 4,000, b represents 0 to 5, c represents 0 to 2,000, and d represents an integer of 0 to 4,000. When R ⁴ is a monovalent organic group not containing an aliphatic unsaturated bond, b is an integer of 2 or more, R ⁴ and R ⁵ , each of R ⁴ and each of R ⁵ are independent and the same It may or may not be. At least one of a, b, and c is an integer of 1 or more, and d is 0 or an integer of 1 or more.

In the compound represented by the general formula (IV) and the functional group represented by the general formula (V), it is determined that R ⁴ and R ⁵ are each 50% by mole or more of a methyl group. It is preferable in terms of ink repellency. Further, the weight average molecular weight of the vinyl group-containing silicone compound is preferably 30,000 or more from the viewpoint of improving printing durability and scratch resistance, and preferably 300,000 or less from the viewpoint of improving image reproducibility.

  The weight average molecular weight of the vinyl group-containing silicone compound can be determined by a generally known Gel Permeation Chromatography-Low Angle Laser Light Scattering method (hereinafter referred to as GPC-LALLS method).

  The content of the vinyl group-containing silicone compound is preferably 60% by weight or more in the silicone rubber layer composition liquid in terms of improving the ink resilience of the silicone rubber layer, and more preferably 70% by weight or more. Moreover, 99 weight% or less is preferable at the point which ensures the sclerosis | hardenability of a silicone rubber layer.

  The ratio of the number of SiH groups in the silicone rubber layer composition liquid and the number of functional groups that undergo a hydrosilylation reaction with SiH groups (the number of SiH groups / the number of functional groups that undergo a hydrosilylation reaction with SiH groups) is preferably 1 or more. When the ratio of the number of SiH groups to the number of functional groups capable of hydrosilylation reaction with SiH groups is less than 1, the silicone rubber layer is insufficiently cured, and printing plate precursors and printing plates such as image reproducibility, printing durability, and ink repulsion Many properties important to can be significantly degraded. If the ratio of the number of SiH groups and the number of functional groups capable of hydrosilylation reaction with SiH groups is 1 or more, it is preferable because the silicone rubber layer is sufficiently cured. In addition, it is preferable that the ratio of the number of SiH groups and the number of functional groups that undergo a hydrosilylation reaction with SiH groups is 2 or less because ink rebound is improved. A range of 1.2 to 1.8 is more preferable.

  A curing catalyst can be used for the addition reaction type silicone rubber layer used for the printing plate which can use the ink removing agent of this invention suitably.

As the curing catalyst, those known as hydrosilylation reaction catalysts can be used, but platinum and rhodium are preferably contained from the viewpoint of high reactivity. Specifically, platinum alone, a carrier (alumina, silica, carbon black, etc.) supported with solid platinum, chloroplatinic acid, platinum-olefin complex, platinum-vinylsilane complex, platinum-vinylsiloxane complex, platinum-phosphine Complexes, platinum-phosphite complexes, platinum-acetylacetone complexes, platinum-acetoacetic acid alkyl ester complexes, platinum-malonic acid dialkyl ester complexes, and Ashby et al. In US Pat. Nos. 3,159,601 and 3,159,662 And the platinum alcohol catalysts described in US Pat. No. 3,220,972 to Lamoreaux et al. Examples of catalysts other than platinum compounds include RhCl (PPh ₃ ) ₃ , RhCl ₃ , Rh / Al ₂ O ₃ , RuCl ₃ , IrCl ₃ , FeCl ₃ , AlCl ₃ , PdCl ₂ .2H ₂ O, NiCl _2. , TiCl _{4 and the} like. These curing catalysts may be used alone or in combination of two or more.

  As a content rate of a curing catalyst, 0.001 weight% or more in a silicone rubber layer composition liquid is preferable at the point which improves the sclerosis | hardenability of a silicone rubber layer, and 0.01 weight% or more is more preferable. Moreover, 20 weight% or less in a silicone rubber layer composition liquid is preferable and the 15 weight% or less is more preferable at the point which improves the stability of a silicone rubber layer composition liquid and the solution.

  As the reaction inhibitor, those known as hydrosilylation reaction inhibitors or reaction retarders can be used. Amine compounds and acetylene compounds are preferred, and pyridine, picoline, 2,2'-dipyridyl, 2-butanone oxime, acetylene alcohol, acetylene silane and the like are more preferred. Examples of acetylene alcohol include 2-methyl-3-butyn-2-ol, 2-phenyl-3-butyn-2-ol, 1-ethynyl-1-hexanol, 3,5-dimethyl-1-hexyne-3- Ol, 3-methyl-1-pentyn-3-ol, and the like. Two or more of these may be contained. By containing these reaction inhibitors, the silicone rubber layer composition liquid and the stability of the solution are improved.

  The content of the reaction inhibitor is preferably 0.01% by weight or more in the silicone rubber layer composition liquid in terms of improving the stability of the silicone rubber layer composition liquid and the solution, and more preferably 0.1% by weight or more. preferable. Moreover, 20 weight% or less is preferable in a silicone rubber layer composition liquid at the point which ensures the sclerosis | hardenability of a silicone rubber layer, and 15 weight% or less is more preferable.

  Next, the condensation reaction type silicone rubber layer used for the printing plate in which the ink remover of the present invention can be suitably used will be described. Examples of the condensation reaction type silicone rubber layer include, but are not limited to, the following condensation reaction type silicone rubber layers.

  It is preferable that at least a silanol group-containing silicone compound and a silane coupling agent are included. A reaction catalyst may also be included.

  Examples of the silanol group-containing silicone compound include compounds represented by general formula (VI), and are organopolysiloxanes having two or more silanol groups in the molecule. Among them, a compound having silanol groups at both ends of the molecular main chain is preferable in terms of improving the curability of the silicone rubber layer. Moreover, you may contain 2 or more types of these.

  In the general formula (VI), J is a functional group represented by the following general formula (VII).

In the general formulas (VI) and (VII), R ⁶ represents either a hydroxyl group or a monovalent organic group, and R ⁷ represents a monovalent organic group. Monovalent organic groups include methyl groups, ethyl groups, propyl groups, butyl groups, pentyl groups, hexyl groups, heptyl groups and other alkyl groups; phenyl groups, toluyl groups, xylyl groups, naphthyl groups and other aryl groups; benzyl Groups, aralkyl groups such as phenethyl group; halogenated alkyl groups such as chloromethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, and the like. e is 0 to 4,000, f is 0 to 5, g is 0 to 2,000, and h is an integer in the range of 0 to 4,000. When R ⁶ is a monovalent organic group, f is an integer of 2 or more, and R ⁶ and R ⁷ are each independent and may be the same or different. Further, at least one of e, f, and g is an integer of 1 or more, and h is 0 or an integer of 1 or more.

In the general formulas (VI) and (VII), it is preferable from the viewpoint of ink repellency of the lithographic printing plate that R ⁶ and R ⁷ are each 50% by mole or more of methyl groups.

  Further, the weight average molecular weight of the silanol group-containing silicone compound is preferably 30,000 or more in terms of improving printing durability and scratch resistance, and preferably 300,000 or less in terms of improving curability and image reproducibility. .

  The weight average molecular weight of the silanol group-containing silicone compound can be measured by the GPC-LALLS method described above.

  The content of the silanol group-containing silicone compound is preferably 60% by weight or more, more preferably 70% by weight or more in the silicone rubber layer composition liquid, from the viewpoint of improving the ink repellency of the silicone rubber layer. Moreover, 99 weight% or less is preferable at the point which ensures the sclerosis | hardenability of a silicone rubber layer.

  The silane coupling agent is preferably a tetrafunctional silane coupling agent and / or a trifunctional silane coupling agent.

  As tetrafunctional silane coupling agents, tetramethoxysilane, tetraethoxysilane, tetranormalpropoxysilane, tetraisopropoxysilane, tetranormalbutoxysilane, tetrakis (2-ethylhexoxy) silane, tetrakis (2-octyldecyloxy) Silane, Tetraallyloxysilane, Tetraphenoxysilane, Tetrakis (methoxyethoxy) silane, Tetrakis (ethoxyethoxy) silane, Tetrakis (1-methoxy-2-propoxy) silane, Tetrakis (methoxyethoxyethoxy) silane, Tetraacetoxysilane, Tetrakis (Trifluoroacetoxy) silane, tetrakis (methylethylketoximino) silane, tetrakis (methylisobutylketoximino) silane, etc. But it is not limited to. Of these, tetraacetoxysilane, tetrakis (trifluoroacetoxy) silane, tetrakis (methylethylketoximino) silane, and tetrakis (methylisobutylketoximino) silane are preferable from the viewpoint of curability. Two or more of these may be contained.

  As a content rate of a tetrafunctional silane coupling agent, it is preferable to contain 0.5 to 1.5 weight% in a silicone rubber layer composition liquid. If it is 0.5% by weight or more, curability is good, and if it is 1.5% by weight or less, scratch resistance is good.

  As the trifunctional silane coupling agent, it is preferable that a trifunctional silane coupling agent represented by the following general formula (VIII) is contained in that the adhesive force to the lower layer can be further improved.

  In general formula (VIII), L represents a substituted or unsubstituted alkyl group having 1 or more carbon atoms, an alkenyl group, an aryl group, or a combination thereof. From the viewpoint of reactivity, an alkenyl group and an aryl group are preferable. M represents a hydrolyzable group and may be the same or different. M is an acyloxy group such as an acetoxy group, a ketoxime group such as a methylethylketoxime group, an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, or a butoxy group, an alkenyloxy group such as an isopropenoxy group, or an acyl such as an acetylethylamino group. Examples include aminoxy groups such as alkylamino groups and dimethylaminoxy groups.

  Specific compounds include acetoxysilanes such as methyltriacetoxysilane, ethyltriacetoxysilane, vinyltriacetoxysilane, allyltriacetoxysilane, phenyltriacetoxysilane, methyltris (methylethylketoximino) silane, ethyltris (methylethylketoximino) ) Ketoximinosilanes such as silane, vinyltris (methylethylketoximino) silane, allyltris (methylethylketoximino) silane, phenyltris (methylethylketoximino) silane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyl Triethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltriethoxysilane, vinyltriisopropoxy Alkoxysilanes such emissions, vinyl tris isopropenoxysilane silane, although such alkenyloxy silanes such as tri-isopropenoxysilane carboxymethyl silanes, but are not limited thereto. Of these, acetoxysilanes and ketoximinosilanes are preferable in terms of reactivity. Two or more of these may be contained.

  The content of the trifunctional silane coupling agent is preferably 1% by weight or more and 10% by weight or less in the silicone rubber layer composition liquid. When it is 1% by weight or more, the adhesion to the lower layer is further improved, and when it is 10% by weight or less, scratch resistance and ink rebound are good.

  In addition to the above-described tetrafunctional silane coupling agent and / or trifunctional silane coupling agent, a silane coupling agent having an amino group may be contained.

  Examples of the silane coupling agent having an amino group include one or more selected from compounds represented by the following general formulas (IX) to (XI).

  In general formulas (IX) to (XI), X represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a toluyl group, and R represents an alkyl group having 1 to 3 carbon atoms.

  R is preferably a methyl group from the viewpoint of improving adhesion to the lower layer and scratch resistance.

  The content of the amino group-containing silane coupling agent is 0.2% by weight or more and 0.4% by weight or less in the silicone rubber layer composition liquid. If the content is within this range, the adhesion to the lower layer is good. It becomes.

  The total content of all silane coupling agents such as a tetrafunctional silane coupling agent, a trifunctional silane coupling agent, and an amino group-containing silane coupling agent is 2% by weight or more in the silicone rubber layer composition liquid. It is preferable to contain 10% by weight or less. If it is 2% by weight or more, the pot life of the silicone rubber layer composition liquid is good, and if it is 10% by weight or less, scratch resistance and ink rebound are good.

  Examples of the catalyst include organic carboxylic acids, acids, alkalis, amines, metal alkoxides, metal diketenates, organic acid salts of metals such as tin, lead, zinc, iron, cobalt, calcium, and manganese. Specific examples include dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, zinc octylate, and iron octylate. Two or more of these may be contained.

  The content of the catalyst is preferably 0.01% by weight or more and 1% by weight or less in the silicone rubber layer composition liquid. If it is 0.01% by weight or more, the curability of the silicone rubber layer and the adhesion to the lower layer are good, and if it is 1% by weight or less, the stability of the silicone rubber layer composition liquid is good.

  For the purpose of further improving the ink repellency of the aforementioned addition reaction type silicone rubber layer and condensation reaction type silicone rubber layer, the silicone rubber layer composition liquid may contain a liquid having a surface tension at 25 ° C. of 30 mN / m or less. preferable. Particularly preferably, each silicone rubber layer composition liquid contains a liquid having a surface tension at 25 ° C. of 30 mN / m or less. If the surface tension is 30 mN / m or less, a liquid having a surface tension of 30 mN / m or less at 25 ° C. appears on the surface of the silicone rubber layer, and the ink resilience is improved to help the ink to peel off. The temperature can be raised. The liquid is more preferably a liquid having a surface tension at 25 ° C. of 22 mN / m or less, and more preferably 21 mN / m or less, in order to improve ink resilience. The surface tension can be measured by a Wilhelmy method (sometimes called a plate method or a vertical plate method) which is a generally known measurement method. Moreover, as a boiling point in 1 atmosphere of the liquid whose surface tension in 25 degreeC is 30 mN / m or less, 150 degreeC or more is preferable. When the boiling point is 150 ° C. or higher, volatilization of a liquid having a surface tension at 25 ° C. of 30 mN / m or less during production and storage of the printing plate precursor is suppressed, and thus high ink resilience can be maintained. The content of the liquid having a surface tension at 25 ° C. of 30 mN / m or less in the silicone rubber layer is preferably in the range of 10 to 25% by weight. If it is 10% by weight or more, the ink resilience is remarkably improved, and if it is 25% by weight or less, the strength of the silicone rubber layer can be sufficiently secured, so that the printing durability can be maintained.

  Since the ink remover of the present invention is highly polar, it has a very low affinity with a liquid having a surface tension at 25 ° C. of 30 mN / m or less and is hardly compatible. For this reason, at the time of ink removal, extraction of a liquid having a surface tension at 25 ° C. of 30 mN / m or less is unlikely to occur, and ink repellency at the ink removal portion is unlikely to decrease.

  The liquid having a surface tension at 25 ° C. of 30 mN / m or less is preferably a silicone compound, and more preferably silicone oil. The term “silicone oil” as used herein refers to a polysiloxane component that is not involved in the crosslinking of the silicone rubber layer. Specifically, polydimethylsiloxane having a trimethylsilyl group at the molecular chain end, cyclic polydimethylsiloxane, dimethylsiloxane-methylphenylsiloxane copolymer having a trimethylsilyl group at the molecular chain end, dimethylsiloxane-diphenylsiloxane copolymer having a trimethylsilyl group at the molecular chain end, etc. Dimethyl silicone oil, alkyl-modified silicone oil, fluorine-modified silicone oil, polyether-modified silicone oil, alcohol-modified silicone oil, amino-modified silicone oil, epoxy-modified silicone oil, epoxy-polyether-modified silicone oil, phenol-modified silicone oil , Carboxy modified silicone oil, mercapto modified silicone oil, amide modified silicone oil, carbana modified Recone oils, and modified silicone oils obtained by introducing various organic groups into a part of methyl groups in the molecule, such as higher fatty acid-modified silicone oil. The molecular weight of a liquid having a surface tension at 25 ° C. of 30 mN / m or less is preferably in the range of 200 to 100,000 in terms of weight average molecular weight. When the weight average molecular weight is 200 or more, the volatilization of the liquid having a surface tension at 25 ° C. of 30 mN / m or less at the time of production and storage of the printing plate precursor is suppressed. Bleed-out is suppressed.

  Further, the silicone rubber layer composition liquid may contain a known reinforcing agent such as silica or Q resin in addition to the above-mentioned compounds for the purpose of improving rubber strength.

  Furthermore, the silicone rubber layer may be colored for the purpose of imparting plate inspection properties to the developed printing plate. Examples of the method for coloring the silicone rubber layer include coloring with a colored dye described in JP-A No. 2002-244279 and coloring with a colored pigment described in WO 2008/056588.

  The silicone rubber layer can be formed by applying the silicone rubber layer composition liquid to the substrate or another layer provided on the substrate. Further, the silicone rubber layer composition solution can be dissolved in a solvent as necessary to form a silicone rubber layer composition solution, which can be applied to a substrate or another layer provided on the substrate to form a silicone rubber layer. It is preferable to degrease the coated surface of the substrate.

  As a coating apparatus, a slit die coater, a gravure coater, and a roll coater are preferable.

The film weight of the silicone rubber layer is preferably in the range of 0.6 to 10 g / m ² . When the film weight of the silicone rubber layer is 0.6 g / m ² or more, the ink repellency, scratch resistance, and printing durability of the printing plate are sufficient, and when it is 10 g / m ² or less, it is disadvantageous from an economic viewpoint. In other words, image reproducibility and ink mileage are less likely to deteriorate. A range of 1 to 5 g / m ² is more preferable.

  When the silicone rubber layer composition solution or the silicone rubber layer composition solution is dried to form a silicone rubber layer, the drying is performed without heating or under heating. When heating, it is preferable to dry at a temperature of 50 to 250 ° C. for 30 seconds to 5 minutes using a hot air dryer or an infrared dryer.

  In addition, the printing plate may have a heat insulating layer for the purpose of improving adhesiveness, preventing light halation, improving plate inspection, improving heat insulation, and improving printing durability. As a heat insulation layer, although the heat insulation layer described in Unexamined-Japanese-Patent No. 2004-199016, Unexamined-Japanese-Patent No. 2004-334025, Unexamined-Japanese-Patent No. 2006-276385 etc. is mentioned, for example, It is not limited to these.

  Next, a method for producing a printing plate from the printing plate precursor will be described. Examples of the method for producing the printing plate include a method including at least a step of exposing the printing plate precursor (exposure step) and a step of removing either the exposed portion or the unexposed portion of the silicone rubber layer (developing step).

  First, the exposure process will be described. Methods for exposing the printing plate precursor include (1) a method in which a positive or negative original film is brought into close contact with the surface of the printing plate precursor and then irradiated with ultraviolet rays from the original film side, and (2) an original film. And a method (CTP) in which an image is directly written on a direct-drawing printing plate precursor using a laser beam having a specific light emission wavelength in accordance with digital data. Examples of the laser light source used for exposure in the CTP method include those having an emission wavelength region in the range of 350 to 1,500 nm.

  Next, the development process will be described. The exposed printing plate precursor is rubbed in the presence or absence of a liquid to remove either the exposed or unexposed silicone rubber layer. Examples of the friction treatment include (i) a method of rubbing the plate surface with a developing pad, brush, dry cotton pad, etc. in the absence of a liquid, (ii) a nonwoven fabric impregnated with water or water added with a surfactant, absorbent cotton , A method of wiping the plate surface with a cloth, a sponge, etc., (iii) a method of rubbing with a rotating brush while bringing water or surfactant-added water into contact with the plate surface, and (iv) jetting high-pressure water, hot water or water vapor onto the plate surface. The method etc. are mentioned. The surfactant is preferably one having a pH of 5 to 8 when the aqueous solution is used, and the surfactant content is preferably 10% by weight or less of the aqueous solution. Such an aqueous solution has high safety and is preferable from the viewpoint of economy such as disposal cost.

  Prior to development, a pretreatment in which a plate is immersed in a pretreatment solution for a certain time may be performed. Examples of the pretreatment liquid include water, polar water such as alcohol, ketone, ester and carboxylic acid added to water, aliphatic hydrocarbons, aromatic hydrocarbons and the like. A solvent added or a polar solvent is used. Among these, a pretreatment liquid using a glycol compound or a glycol ether compound as a main component is preferable. Moreover, you may add an amine compound, surfactant mentioned above, etc. in a pretreatment liquid.

  Examples of the pretreatment liquid include pretreatments described in JP-A-63-179361, JP-A-4-163557, JP-A-4-343360, JP-A-9-34132, and WO1997 / 017634. A liquid etc. can be mentioned. Specific examples of the pretreatment liquid include PP-1, PP-3, PP-F, PP-FII, PTS-1, PH-7N, CP-1, NP-1, DP-1, CP-Y (any And Toray Industries, Inc.).

  In addition, for the purpose of improving the visibility of the image area and the measurement accuracy of halftone dots, dyes such as crystal violet, Victoria Pure Blue, Astrazone Red, etc. are added to water or water with a surfactant added to the image at the same time as development. It is also possible to dye the ink receiving layer at the line part. Furthermore, it can also dye | stain with the liquid which added the said dye after image development.

  Part or all of the developing process can be automatically performed by an automatic developing machine. As an automatic developing machine, a device having only a developing unit, a device in which a pre-processing unit and a developing unit are provided in this order, a device in which a pre-processing unit, a developing unit and a post-processing unit are provided in this order, a pre-processing unit, a developing unit, An apparatus or the like provided with a post-processing section and a water washing section in this order can be used. Specific examples of such an automatic developing machine include TWL-650 series, TWL-860 series, TWL-1160 series (all manufactured by Toray Industries, Inc.), JP-A-4-2265, and JP-A-5- Examples thereof include automatic developing machines disclosed in Japanese Patent No. 2272, Japanese Patent Application Laid-Open No. 5-6000, and the like, and these can be used alone or in combination.

  For the purpose of further improving resistance to chemicals such as ink and ink remover, the printing plate may be subjected to heat treatment (hereinafter referred to as burning treatment). When the printing plate before development (before exposure and after exposure) is subjected to a burning treatment, the sensitivity and developability of the printing plate are remarkably lowered. Therefore, the burning treatment is preferably performed on the printing plate after development. For the burning treatment of the printing plate after development, a generally known heating device such as a hot air dryer, an infrared dryer, or a burning processor can be used. The temperature of the burning treatment is preferably 140 ° C. or higher from the viewpoint of improving chemical resistance, and preferably 300 ° C. or lower from the viewpoint of suppressing decomposition of the compound constituting the printing plate, although it depends on the type of components of the printing plate. The burning treatment time is preferably 0.5 minutes or more from the viewpoint of improving chemical resistance, and preferably 60 minutes or less from the viewpoint of productivity of the printing plate.

  Among the resin layers such as the heat-sensitive layer or the photosensitive layer described above, in the present invention, the effect of improving the chemical resistance by the burning treatment is particularly remarkable. In the present invention, the heat-sensitive layer or the photosensitive layer having the phenol resin or the metal chelate is used. It is preferable that the resin layer is used. That is, in this invention, it is one of the preferable aspects that the resin layer of a printing plate contains a metal chelate. It is more preferable to use a resin layer such as a heat-sensitive layer or a photosensitive layer having the phenol resin and the metal chelate at the same time.

  As metal chelates, Al (III), Fe (II), Fe (III), Ti (IV), Zr (IV) β-diketone complexes, β-ketoester complexes, β-diester complexes, triethanolamine complexes, etc. Is mentioned. Among these, a β-diketone complex or β-ketoester complex of Ti (IV) is preferable from the viewpoint of the pot life of the heat-sensitive layer composition liquid and the photosensitive layer composition liquid and the chemical resistance of the printing plate.

  As the β-diketone complex of Ti (IV), titanium dimethoxybis (acetylacetonate), titanium diethoxybis (acetylacetonate), titanium di-n-propoxybis (acetylacetonate), titanium di-iso-propoxy Bis (acetylacetonate), Titanium di-n-butoxybis (acetylacetonate), Titanium di-sec-butoxybis (acetylacetonate), Titanium di-tert-butoxybis (acetylacetonate), Titanium tetrakis (acetylacetonate) , Titanium dimethoxybis (2,2,6,6-tetramethyl-3,5-heptanedionate), titanium diethoxybis (2,2,6,6-tetramethyl-3,5-heptanedionate), Titanium N-propoxybis (2,2,6,6-tetramethyl-3,5-heptanedionate), titanium di-iso-propoxybis (2,2,6,6-tetramethyl-3,5-heptane Diate), titanium di-n-butoxybis (2,2,6,6-tetramethyl-3,5-heptanedionate), titanium di-sec-butoxybis (2,2,6,6-tetramethyl-3) , 5-heptanedionate), titanium di-tert-butoxybis (2,2,6,6-tetramethyl-3,5-heptanedionate), titanium tetrakis (2,2,6,6-tetramethyl-3) , 5-heptanedionate) and the like, but is not limited thereto.

  Examples of the β-ketoester complex of Ti (IV) include titanium dimethoxybis (methyl acetoacetate), titanium diethoxybis (methyl acetoacetate), titanium di-n-propoxy bis (methyl acetoacetate), and titanium di-iso-propoxy. Bis (methylacetoacetate), Titanium di-n-butoxybis (methylacetoacetate), Titanium di-sec-butoxybis (methylacetoacetate), Titanium di-tert-butoxybis (methylacetoacetate), Titanium tetrakis (methylacetoacetate) , Titanium dimethoxybis (ethyl acetoacetate), titanium diethoxybis (ethyl acetoacetate), titanium di-n-propoxybis (ethyl acetoacetate) Titanium di-iso-propoxy bis (ethyl acetoacetate), titanium di-n-butoxy bis (ethyl acetoacetate), titanium di-sec-butoxy bis (ethyl acetoacetate), titanium di-tert-butoxy bis (ethyl acetoacetate), titanium Tetrakis (ethyl acetoacetate), Titanium dimethoxybis (propyl acetoacetate), Titanium diethoxybis (propyl acetoacetate), Titanium di-n-propoxybis (propyl acetoacetate), Titanium di-iso-propoxybis (propyl acetoacetate) ), Titanium di-n-butoxybis (propylacetoacetate), titanium di-sec-butoxybis (propylacetoacetate), titanium Di-tert-butoxybis (propyl acetoacetate), titanium tetrakis (propyl acetoacetate), titanium dimethoxybis (butyl acetoacetate), titanium diethoxybis (butyl acetoacetate), titanium di-n-propoxybis (butyl acetoacetate) Titanium di-iso-propoxy bis (butyl acetoacetate), titanium di-n-butoxy bis (butyl acetoacetate), titanium di-sec-butoxy bis (butyl acetoacetate), titanium di-tert-butoxy bis (butyl acetoacetate), Although titanium tetrakis (butyl acetoacetate) etc. can be mentioned, it is not limited to these.

  As another method for producing a printing plate, the silicone rubber layer composition solution or the silicone rubber layer composition solution is directly patterned on the substrate or another layer provided on the substrate using an inkjet or the like. And a method of drying and curing the silicone rubber layer under heating or non-heating. In the case of heating, it is preferable to dry at a temperature of 50 to 150 ° C. for 30 seconds to 5 minutes using a hot air dryer or an infrared dryer.

  Next, an ink removing method in printing will be described. In the present invention, it is preferable to employ a method in which the ink attached to the printing plate is removed using the ink remover of the present invention. Ink adhering to the surface of each cylinder, roller, blanket, and printing plate of a printing press can be removed by wiping with a nonwoven fabric, absorbent cotton, or cloth (such as a waste cloth) containing the ink removing agent of the present invention. Further, when the printing press is equipped with an automatic cleaning mechanism, the ink may be automatically removed using the ink removing agent of the present invention in the automatic cleaning mechanism. Furthermore, when using a roller or blanket as a roller or blanket, the main component of the surface rubber is an EPDM roller or blanket, and a printing plate having a resin layer such as a heat-sensitive layer or photosensitive layer containing phenol resin is used as the printing plate. Since all of the plates can be deinked with one type of ink remover of the present invention, it is not necessary to prepare many types of ink removers. Furthermore, if the roller is brought into contact with the printing plate mounted on the plate cylinder and the ink is removed while the roller is in the cylinder, the ink can be removed from the roller, the printing plate and the blanket at the same time, so that the ink removal time can be shortened.

  When resuming printing after removing ink, if a large amount of ink remover remains on the surface of rollers, printing plates, blankets, etc., the remaining ink remover and ink will mix and change the physical properties of the ink. The ink remover is preferably dried before printing because it tends to cause printing defects such as background stains. If the ink remover has a high drying property, printing may be resumed immediately after removing the ink without going through a special drying step. As a drying method of the ink remover, a method of rotating (idling) with the roller, plate cylinder, blanket cylinder of the printing press in contact or non-contact, dry nonwoven fabric, absorbent cotton, cloth (cloth etc.) The method of wiping with paper, the method of blowing with a blower, the method of passing paper, such as spear paper, in the state which contacted the roller of the printing machine, the plate cylinder, and the blanket cylinder, etc. are mentioned. Moreover, you may implement combining these methods.

  Hereinafter, the present invention will be described in more detail with reference to examples. Moreover, evaluation in each Example and Comparative Example was performed by the following method.

<Evaluation method in each example and comparative example>
(1) Weight average molecular weight measurement of silicone compound (GPC-LALLS method)
The weight average molecular weights of the vinyl group-containing silicone compound and the silanol group-containing silicone compound were determined under the following conditions.
<Measurement conditions>
a. GPC
Apparatus: 201D type gel permeation chromatograph (manufactured by Nippon Waters Co., Ltd.)
Column: TSK-GEL-GMH6: 2 pieces, G2500H _XL : 1 piece (manufactured by Tosoh Corporation)
Solvent: Toluene Flow rate: 0.8 ml / min Temperature: 23 ° C
Sample concentration: 0.300% (wt / vol)
Solubility: Complete dissolution injection amount: 0.4 ml
Concentration detector: differential refractive index detector: R-401 (manufactured by Nippon Waters Co., Ltd.)
b. LALLS
Apparatus: KMX-6 type low angle laser light scattering photometer (Chromatix)
Wavelength: 633nm
Refractive index density change (dn / dc): Measured value device obtained under the following conditions: KMX-16 laser differential refractometer (manufactured by Chromatix)
Wavelength: 633nm
Solvent: Toluene Temperature: 23 ° C
Gain: P ₀ = 500 mV
Temperature: 23 ° C
Filter: 0.3 μ-Fluoro Pore FP-030 (manufactured by Sumitomo Electric Co., Ltd.).

(2) Evaluation of drying property of ink removing agent The drying property of the ink removing agent was evaluated by the following method.

  Printing machine: The image area (5 cm long x 10 cm wide) of the printing plate attached to the plate cylinder of “OLIVER” 466SD (manufactured by Sakurai Graphic Systems Co., Ltd.) was wiped with a waste cloth containing an ink remover. Thereafter, the plate cylinder was idled at a speed of 2000 rpm, and the dry state of the ink remover after an arbitrary time was evaluated. Dryability is very good when dry after 5 minutes (score: A), dryness when dry completely after 8 minutes (score: B +), dry when dry completely after 10 minutes Slightly good (score: B) and poorly dry (score: C) when not completely dry even after 10 minutes of idling.

The image area of the printing plate was prepared under the following plate making (exposure and development) conditions.
<Exposure conditions>
Exposure machine: “PlateRite” 8800E (Dainippon Screen Mfg. Co., Ltd.)
Exposure amount: 125 mJ / cm ²
<Development conditions>
Automatic processor: TWL-1160FII (manufactured by Toray Industries, Inc.)
Pretreatment liquid: CP-Y (manufactured by Toray Industries, Inc., liquid temperature: 45 ° C.)
Developer: tap water (solution temperature: 30 ° C)
Post-treatment liquid: PA-1 (manufactured by Toray Industries, Inc., liquid temperature: 30 ° C.)
Flushing: tap water (liquid temperature: 30 ° C)
Development speed: 80 cm / min.

(3) Evaluation of ink removability The ease of wiping the ink when the image area of the printing plate on which the ink was developed (5 cm long × 10 cm wide) was wiped with a waste cloth containing an ink remover was evaluated. . When the ink could be removed within 1 reciprocation of the waste cloth, the removability was very good (score: A), and when the ink could be removed within 5 reciprocations, the removability was good (score: B). If the ink cannot be removed within 5 reciprocations, the score is C or D. Specifically, if the ink is removed within 10 reciprocations, the removability is somewhat good (score: C). The case where removal was not possible was defined as poor removal (score: D).

(4) Evaluation of resistance to ink remover of heat-sensitive layer and photosensitive layer Place a cotton pad (5cm x 5cm) on the non-image area of the printing plate held at 30 ° C on a hot plate, and remove ink on the cotton pad. After containing the agent, it was allowed to stand for an arbitrary time. After an arbitrary time, the cotton pad containing the ink removing agent was removed and rubbed strongly 10 times with a dry waste, and the degree of peeling of the silicone rubber layer accompanying the damage of the heat sensitive layer was observed. The test was carried out every 30 minutes until the silicone rubber layer was peeled up to 600 minutes.
・ Removal agent resistance when the silicone rubber layer peels off in 30 minutes: <30 minutes ・ Removal agent resistance when the silicone rubber layer does not peel off in 30 minutes and peeling off in 60 minutes: Silicone rubber in 30 minutes and 60 minutes Remover resistance when the layer does not peel off and peels off in 90 minutes: Silicone rubber layer does not peel off at 60 minutes / 90 minutes, and remover resistance when peels off at 120 minutes: silicone rubber at 90 minutes / 120 minutes Remover resistance when the layer does not peel off and peels off after 150 minutes: Silicone rubber layer does not peel off at 120 minutes / 150 minutes, and remover resistance when peels off after 180 minutes: silicone rubber at 150 minutes / 180 minutes Remover resistance when the layer does not peel and peels after 210 minutes: 180 minutes / 210 minutes The silicone rubber layer does not peel, and when the peeler peels after 240 minutes: Remover resistance: 210 minutes / 240 minutes Remover resistance when the rubber layer does not peel off and peels off at 270 minutes: Silicone rubber layer does not peel off at 240 minutes and 270 minutes, and remover resistance when peels off at 300 minutes: silicone at 270 minutes and 300 minutes Remover resistance when the rubber layer does not peel and peels after 330 minutes: Silicone rubber layer does not peel after 300 minutes / 330 minutes Remover resistance when peels after 360 minutes: Silicone after 330 minutes / 360 minutes Remover resistance when the rubber layer does not peel off after 390 minutes: Silicone rubber layer does not peel off after 360 minutes and 390 minutes, and remover resistance when peeled after 420 minutes: silicone after 390 minutes and 420 minutes Remover resistance when the rubber layer does not peel off and peels after 450 minutes: 420 minutes / 450 minutes When the silicone rubber layer does not peel off and peels after 480 minutes, remover resistance: 45 Remover resistance when the silicone rubber layer does not peel off at 480 minutes and 480 minutes, and remover resistance when peeled off at 540 minutes: 510 Remover resistance when the silicone rubber layer does not peel off at 540 minutes / minutes: 570 minutes when the silicone rubber layer does not peel off at 540 minutes / 570 minutes: Remover resistance when peeled after 600 minutes: 570 minutes Remover resistance when the silicone rubber layer does not peel in minutes / 600 minutes:> 600 minutes.

(5) Evaluation of Ink Removal Scratch Resistance of Silicone Rubber Layer The non-image area (range of 10 cm x 10 cm) of the printing plate attached to the plate cylinder of a printing machine is strongly 10 with a waste cloth containing an ink remover. After reciprocating, printing was performed under the following printing conditions.
<Printing conditions>
Ink roller: Trust Zeta (manufactured by Technoroll Co., Ltd.)
Blanket: MC1300 (manufactured by Kinyo)
Ink: High sensitivity UV ink: Rich Cure WL Process SI-H3 Black N (manufactured by Inner and Outer Ink Manufacturing Co., Ltd.)
Solid part reflection density on printed matter: 1.8
Plate temperature: 28 ° C
Printing speed: 8,000 sph
Media to be printed: OK top coat + (Oji Paper Co., Ltd.)

  Scratch resistance was good (score: A) when no scratches derived from ink removal were observed on the printed matter, and scratch resistance was poor (score: B) when scratches derived from ink removal were observed.

(6) Evaluation of ink repellency after removing ink on plate surface 30 reciprocations of the non-image area (10cm x 10cm) of the printing plate attached to the plate cylinder of the printing press with an ink remover. After wiping, printing was performed under the following printing conditions.
<Printing conditions>
Ink roller: Trust Zeta (manufactured by Technoroll Co., Ltd.)
Blanket: MC1300 (manufactured by Kinyo)
Ink: High sensitivity UV ink: Rich Cure WL Process SI-H3 Black N (manufactured by Inner and Outer Ink Manufacturing Co., Ltd.)
Non-wiped white solid portion reflection density on printed matter: 0.10
Plate temperature: 28 ° C
Printing speed: 2,000 sph
Media to be printed: OK top coat + (Oji Paper Co., Ltd.)

  When the non-image area reflection density on the printed material corresponding to the portion wiped with the ink remover is 0.15 or less, the ink resilience is good (rating: A), and when it is 0.20 or less, the ink resilience is When the ink was slightly poor (score: B) and 0.21 or more, it was defined as ink repellent defect (score: C).

(7) Evaluation of Ink Remover Resistance of Ink Roller and Blanket In order to evaluate damage to the surface rubber of the ink roller and blanket by the ink remover, the swelling rate of the surface rubber of the ink roller and blanket after immersion of the ink remover is determined. It measured by the following method. The greater the swelling rate after immersion in the ink remover, the greater the damage to the surface rubber of the ink roller and the blanket, and the more likely to cause printing defects due to deformation.

The surface rubber part of the ink roller and the blanket was cut into a size of 10 × 10 × 1 mm, and the weight was measured (weight A). The cut sample after the weight measurement was put into a screw tube (capacity: 30 ml) filled with an ink remover and allowed to stand at 35 ° C. for 48 hours. The cut sample that was allowed to stand for 48 hours in the ink remover was taken out from the screw tube, and the ink remover adhering to the surface was lightly wiped off with a cotton pad, and the weight was immediately measured (weight B). Using the measured values of weight A and weight B obtained, the swelling rate [wt%] was determined by the following calculation method.
Swelling ratio [% by weight] = 100 × (weight B [g] −weight A [g]) / weight A [g]

  When the swelling rate is 0% by weight, there is no damage (score: A), when 1-5% by weight is slightly damaged (score: B), and when it is 6% by weight or more, the damage is high (score: C). .

[Examples 1-9, Comparative Examples 1-8]
Change the type of ink remover and use the methods described above to dry the ink remover, remove the ink, resist the ink remover on the heat sensitive layer, resist the ink removed from the silicone rubber layer, and repel the ink after removing the plate ink. Evaluated.

  As an ink for evaluating ink removability, high-sensitivity UV ink: Rich Cure WL Process SI-H3 Black N (manufactured by Inner and Outer Ink Manufacturing Co., Ltd.) was used.

The following were used as the ink remover.
・ Ethylene glycol diacetate (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ Propylene glycol diacetate (Wako Pure Chemical Industries, Ltd.)
1,4-butanediol diacetate: “Certor” (registered trademark) 1,4-BDDA (manufactured by Daicel Corporation)
・ 1,3-Butylene glycol diacetate: “Certor” 1,3-BGDA (manufactured by Daicel Corporation)
1,6-hexanediol diacetate: “Certor” 1,6-HDDA (manufactured by Daicel Corporation)
・ 1,2-propylene glycol dibutyrate (manufactured by Inoue Fragrance Co., Ltd.)
・ Dimethyl maleate (Wako Pure Chemical Industries, Ltd.)
・ Diethyl oxalate (Wako Pure Chemical Industries, Ltd.)
・ Diethyl malonate (Wako Pure Chemical Industries, Ltd.)
・ Dimethyl succinate (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ Dibenzyl ether (Wako Pure Chemical Industries, Ltd.)
・ Ethylene glycol monoethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ 3-Methoxy-3-methyl-1-butanol (manufactured by Wako Pure Chemical Industries, Ltd.)
Propylene glycol monomethyl ether acetate (manufactured by Tokyo Chemical Industry Co., Ltd.).

  The following were used as printing plates.

The following heat insulation layer composition solution was applied onto a 0.24 mm thick degreased aluminum substrate (Mitsubishi Aluminum Co., Ltd.) and dried at 200 ° C. for 90 seconds to form a heat insulation layer having a membrane weight of 10 g / m ^2. Provided.

<Insulation layer composition solution>
Add the following component (a) into the container and stir the components (b), (c), (d), (e) slowly while stirring with a three-one motor, and stir and mix until the components are uniform. did. The components (f) and (g) were added to the obtained mixed solution and stirred and mixed for 10 minutes to obtain a heat insulating layer composition solution.
(A) The following titanium oxide dispersion: N, N-dimethylformamide dispersion (Titanium oxide 50% by weight) of “Taipeku” (registered trademark) CR-50 (manufactured by Ishihara Sangyo Co., Ltd.): 60 parts by weight (b) Epoxy resin: “JER” (registered trademark) 1010 (manufactured by Mitsubishi Chemical Corporation): 35 parts by weight (c) Polyurethane: “Samprene” (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., solid content concentration) (20% by weight): 375 parts by weight (d) N, N-dimethylformamide: 730 parts by weight (e) Methyl ethyl ketone: 250 parts by weight (f) Aluminum chelate: “Aluminum chelate” ALCH-TR (Kawaken Fine Chemical Co., Ltd.) 10 parts by weight (g) Leveling agent: “Disparon” (registered trademark) LC951 (manufactured by Enomoto Kasei Co., Ltd., solid content: 10% by weight): 1 part by weight.

<Preparation of titanium oxide dispersion>
Zirconia beads: N, N-dimethylformamide: 500.0 g in a sealable glass standard bottle filled with 1,600.0 g of “YTZ” (registered trademark) balls (φ1 mm, manufactured by Nikkato Co., Ltd.) "Tipeke" (registered trademark) CR-50 (Ishihara Sangyo Co., Ltd.): 500.0 g was charged, sealed, and then set on a small ball mill rotating stand (manufactured by ASONE Co., Ltd.), rotating at 0.4 m / sec. By dispersing for 7 days at a speed, a titanium oxide dispersion was obtained.

Next, the following heat-sensitive layer composition solution was applied onto the heat insulating layer and heated at 140 ° C. for 90 seconds to provide a heat-sensitive layer having a film weight of 1.4 g / m ² . The thermosensitive layer composition solution was obtained by stirring and mixing the following components at room temperature.

<Thermosensitive layer composition solution>
(A) Phenol formaldehyde novolak resin: “Sumilite Resin” (registered trademark) PR53195 (manufactured by Sumitomo Bakelite Co., Ltd.): 45.0 parts by weight (b) Polyurethane solution: “Nipporan” (registered trademark) 5196 (Nippon Polyurethane ( Co., Ltd., solid content concentration: 30% by weight): 62.5 parts by weight (c) Infrared absorbing dye: “PROJET” 825LDI (manufactured by Avecia): 12.0 parts by weight (d) Titanium di-n- Butoxybis (acetylacetonate) solution: “Narsem” (registered trademark) titanium (manufactured by Nippon Chemical Industry Co., Ltd., solid content concentration: 73% by weight): 28.5 parts by weight (e) polyoxypropylenediamine / glycidyl methacrylate / 3-glycidoxypropyltrimethoxysilane = 1/3/1 mole of reactant (solid content: 50% by weight) : 22.5 parts by weight (f) tetrahydrofuran: 717.0 parts by weight (g) of ethanol: 112.5 parts by weight.

Next, the following silicone rubber layer composition solution-1 was applied onto the heat-sensitive layer and heated at 140 ° C. for 80 seconds to provide a silicone rubber layer having a film weight of 2.0 g / m ² .

<Silicone rubber layer composition solution-1>
The following components (a), (b), and (c) were charged into a container and stirred and mixed until the components became uniform. The resulting solution was bubbled with dry nitrogen for 20 minutes to remove moisture in the solution. The components (d), (e), and (f) were added to the obtained solution and stirred and mixed for 10 minutes, and then the component (g) was added and stirred and mixed for another 10 minutes. Immediately before coating, the component (h) was added and mixed by stirring to obtain a silicone rubber layer composition solution-1.
(A) Isoparaffinic solvent: “Isopar” (registered trademark) E (manufactured by ExxonMobil Chemical Co.): 894.05 parts by weight (b) Vinyl group-containing silicone compound (both ends dimethylvinylsiloxy-polydimethylsiloxane): “DMS "-V35 (manufactured by GELEST Inc., weight average molecular weight: 49,500, number of vinyl groups in the molecule: 2): 73.68 parts by weight (c) liquid having a surface tension at 25 ° C. of 30 mN / m or less (both Terminal trimethylsiloxy-polydimethylsiloxane): KF-96-50cs (manufactured by Shin-Etsu Chemical Co., Ltd., viscosity average molecular weight: 3,780, surface tension at 25 ° C .: 20.8 mN / m, boiling point:> 150 ° C.) : 20.00 parts by weight (d) SiH group-containing compound (both terminals trimethylsiloxy-methylhydrosiloxane-dimethylsiloxane copolymer) Limer): “HMS” -301 (manufactured by GELEST Inc., weight average molecular weight: 1,960, SiH group equivalent: 245, number of SiH groups in the molecule: 8): 2.27 parts by weight (e) Vinyl tris (methyl ethyl ketoximi) B) Silane: 1.00 parts by weight (f) Phenyltriacetoxysilane: 3.00 parts by weight (g) Reaction inhibitor: γ-picoline: 1.00 parts by weight (h) Reaction catalyst (platinum mixture): XC94- C4326 (Momentive Performance Materials Japan GK, solid content concentration: 1% by weight): 5.00 parts by weight.

  Tables 1 and 2 show the conditions and results for each level.

[Examples 10 to 12]
The ink removal property was evaluated by the method described above by changing the ink type.
・ LED-UV ink: Flash dry LED Acquares FC black 2M (manufactured by Toyo Ink Co., Ltd.)
・ UV ink: Best Cure UV171CT Black M-TW (manufactured by T & K TOKA)
・ Oil ink: Dry color naturalis ink N (manufactured by DIC Graphics)
Table 3 shows the conditions and results for each level.

[Examples 13 to 15]
The heat-sensitive layer and the silicone rubber layer were changed as follows, and the ink removing agent resistance of the heat-sensitive layer or the photosensitive layer, the ink removal scratch resistance of the silicone rubber layer, and the ink rebound after removing the plate surface ink were evaluated by the methods described above. (The level (Examples 14 and 15) using the silicone layer composition solution-3 containing no liquid having a surface tension at 25 ° C. of 30 mN / m or less was not evaluated for ink resilience).

<Photosensitive layer composition solution>
(A) Partially esterified product of 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride and “Sumilite Resin” PR50731 <Esterification degree 36%>: 100 parts by weight (b) “Samprene” (registered trademark) LQ-T1331D: 50 parts by weight (c) 4,4′-bis (diethylamino) benzophenone: 10 parts by weight (d) Polyisocyanate: “Millionate” MR200: 20 parts by weight (e) Dibutyltin diacetate: 0.2 parts by weight (F) Acetic acid: 2 parts by weight (g) Tetrahydrofuran: 800 parts by weight.

<Silicone rubber layer composition solution-2>
The following components (a), (b), and (c) were charged into a container and stirred and mixed until the components became uniform. The resulting solution was bubbled with dry nitrogen for 20 minutes to remove moisture in the solution. The component (d) was added to the obtained solution and stirred and mixed for 10 minutes, and then the component (e) was added and stirred and mixed for 10 minutes to obtain a silicone rubber layer composition solution-2.
(A) “Isopar” (registered trademark) E: 900.00 parts by weight (b) Silanol group-containing silicone compound (both ends silanol-polydimethylsiloxane): “DMS” -S35 (manufactured by GELEST Inc., weight average molecular weight: 49,000, number of silanol groups in the molecule: 2): 73.68 parts by weight (c) KF-96-50cs: 20.00 parts by weight (d) vinyltris (methylethylketoximino) silane: 6.27 parts by weight ( e) Reaction catalyst: dibutyltin diacetate: 0.05 parts by weight.

<Silicone rubber layer composition solution-3>
The following components (a) and (b) were charged into a container and mixed with stirring until the components were uniform. The resulting solution was bubbled with dry nitrogen for 20 minutes to remove moisture in the solution. The components (c), (d), and (e) were added to the obtained solution and stirred and mixed for 10 minutes, and then the component (f) was added and stirred and mixed for another 10 minutes. Immediately before coating, the component (g) was added and mixed by stirring to obtain a silicone rubber layer composition solution-3.
(A) "Isopar" (registered trademark) E: 894.05 parts by weight (b) "DMS" -V35: 93.68 parts by weight (c) "HMS" -301: 2.27 parts by weight (d) Vinyl tris ( Methylethylketoximino) silane: 1.00 parts by weight (e) Phenyltris (methylethylketoximino) silane: 3.00 parts by weight (f) γ-picoline: 1.00 parts by weight (g) XC94-C4326: 5.00 Parts by weight.

  Table 4 shows the conditions and results for each level.

[Examples 16 to 20]
The ink roller and blanket were changed, and the ink remover resistance of the ink roller and blanket was evaluated by the method described above.

<Ink roller>
・ UV-B (manufactured by Kinyo Co., Ltd., surface material: EPDM)
・ Super Rex (Miyakawa Roller Co., Ltd., surface material: NBR)
・ Trust Zeta (manufactured by Technoroll Co., Ltd., surface material: urethane resin).

<Blanket>
MC1300 (manufactured by Kinyo Co., Ltd., surface material: EPDM)
S7400 (manufactured by Kinyo Co., Ltd., surface material: NBR).

  Table 5 shows the conditions and results for each level.

[Examples 21 to 32, Comparative Examples 9 to 11]
Change the type of heat-sensitive layer and photosensitive layer, type of silicone rubber layer, printing plate burning treatment after development, and type of ink remover. The ink resilience after removal was evaluated.

  Table 6 shows the conditions and results for each level.

Claims (14)

An ink remover used for printing using ink, comprising at least a compound represented by the following general formula (I):
(In the formula, R ¹ and R ² represent a saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms, which may be linear or branched, and may be the same or different. R ³ represents a saturated or unsaturated hydrocarbon group having 2 to 6 carbon atoms, and may be linear, branched or cyclic. The ink removing agent according to claim 1, wherein R ^{3 of the} compound represented by the general formula (I) is a branched saturated hydrocarbon group having 3 to 6 carbon atoms. The ink removing agent according to claim 1 or 2, wherein R ¹ and R ² of the compound represented by the general formula (I) are both methyl groups. The ink removing agent according to claim 1, wherein the compound represented by the general formula (I) is propylene glycol diacetate. The ink remover according to any one of claims 1 to 4, wherein the ink is an active energy ray-curable ink. An ink removing method comprising: removing the ink adhering to the printing plate using the ink remover according to any one of claims 1 to 4. The ink removing method according to claim 6, wherein the ink adhering to the printing plate is removed with a non-woven fabric, absorbent cotton or cloth containing the ink removing agent according to claim 1. The ink removing method according to claim 6 or 7, wherein the printing plate has a resin layer and / or a rubber layer. 9. The ink removing method according to claim 8, wherein the resin layer and / or the rubber layer of the printing plate has heat sensitivity or photosensitivity. The ink removing method according to claim 8 or 9, wherein the resin layer of the printing plate contains at least a phenol resin. The ink removing method according to claim 8, wherein the resin layer of the printing plate contains a metal chelate. The ink removing method according to claim 8, wherein the rubber layer of the printing plate is a silicone rubber layer. The ink removing method according to claim 12, wherein the silicone rubber layer of the printing plate contains a liquid having a surface tension of at least 30 mN / m at 25 ° C. The ink removing method according to claim 6, wherein the printing plate is a printing plate subjected to a burning process.