JPWO2020031773A1 - Inkjet ink, film forming method using it, ink coating film, cured silicone rubber film and multifunctional film - Google Patents

Abstract

An object of the present invention is that when a protective layer containing a silicone rubber is formed on an organic electronic device by inkjet printing, it can be applied directly, there is no damage to the organic electronic device, and the protective layer is further coated. To provide an inkjet ink having high ejection stability, a film forming method using the ink, an ink coating film, a cured silicone rubber film, and a multifunctional film, which can obtain high gas barrier properties even if a direct sealing layer is provided. Is.
The ink for inkjet of the present invention is an ink for inkjet containing a liquid silicone rubber, and at least a liquid silicone rubber (A) having a unit structure represented by the general formula (A), a catalyst (B), and the like. It is characterized by containing a volatile siloxane diluent (C) and a surface tension modifier (D).
[Chemical 1]

Description

The present invention relates to an ink for inkjet, a film forming method using the ink, an ink coating film, a cured silicone rubber film, and a multifunctional film. More specifically, the protection containing the cured silicone rubber by inkjet printing on an organic electronic device. When forming the layer, it can be applied directly, there is no damage to the organic electronic device, and even if a sealing layer is provided directly on the protective layer, high gas barrier property can be obtained, and the discharge stability is high. Regarding expensive inkjet inks and the like.

Since organic electronic devices are sensitive to moisture, sealing is essential. Generally, the sealing layer having a gas barrier property provided on an organic electronic device is often an inorganic film formed by a chemical vapor deposition method (hereinafter referred to as CVD: chemical vapor deposition).

When the sealing layer is provided, it is not a film that is too hard to break while covering the unevenness of the organic electronic device to some extent, and low molecular weight components (monomer, polymerization initiation) from the smooth layer and the sealing layer provided on the upper layer. In order to avoid damage to the organic functional layer and electrode corrosion due to diffusion of agents, solvents, etc.), a relatively thick protective layer on the order of microns is required as a layer that is in direct contact with the organic electronic device, and the protective layer is also subjected to CVD. The current situation is that it is formed.

However, although the protective layer employs CVD, it does not contribute to gas barrier properties. Therefore, if the function can be replaced by a coating film formed by coating instead of CVD, a special type such as a vacuum device or a vapor deposition device can be used. Since no equipment is required, the generation of defects and foreign substances derived from CVD film formation can be reduced, and an improvement in product yield can be expected.

Further, if the protective layer can be replaced with a coating film, the tact time can be shortened, which is a great cost advantage.

In addition, if the protective layer can be replaced with a coating film, the layer thickness of the smoothing layer can be reduced, and if the conventional smoothing function can be imparted, the protective layer and the smoothing layer become integrated and become a layer. It is possible to contribute to the reduction of the number.

Further, if the protective layer by the coating can also serve as a smooth layer, the coating film has a higher leveling performance than the CVD film when the sealing layer is directly provided on the sealing layer. It can also contribute to the improvement of the film quality of itself, and further improvement of gas barrier property can be expected.

Further, if the protective layer can be replaced with an organic resin film having high stress relaxation property against a hard CVD inorganic film which is a sealing layer, the bending resistance of the organic electronic device can be significantly improved.

Therefore, substituting the protective layer with a coating film has great advantages in terms of performance and production.

Conventionally, the following techniques are known as techniques for providing a sealing layer by direct coating on an organic electronic device.

Patent Document 1 discloses a technique of using a siloxane having a low viscosity by controlling the degree of polymerization as an ink for a sealing layer in order to enable ejection by inkjet even without a solvent, but the viscosity is adjusted to a desired level. Therefore, it is necessary to optimize the structure of the siloxane before cross-linking, and it is not easy to control the film thickness. In addition, it is not sufficient to reduce the viscosity optimally for stable discharge, and the surface tension of the siloxane liquid is too low, so that the liquid gets wet and spreads on the head discharge part, causing liquid dripping and other concerns about discharge stability. ..

Patent Document 2 discloses that a non-aromatic solvent that does not damage an organic electronic device or an electrode is used, or the content of the solvent is reduced as much as possible. However, an aromatic solvent is disclosed. It is clear that even a non-aromatic or non-aromatic solvent containing even a small amount of a polar solvent diffuses and adversely affects organic electronic devices and electrodes. There is no disclosure regarding a solvent that does not adversely affect organic electronic devices even if it is further diffused.

Further, a polymerization initiator is required to cure the epoxy compound disclosed in Patent Document 2, and such an initiator which is a small molecule and ionic acid generator damages organic electronic devices. Is not preferable because of concern.

Pat. Although there is a disclosure of a solvent, since the surface tension of a liquid in which all of the resin component and the solvent are siloxane compounds is very low, stable ink ejection cannot be expected, and it is not at a practical level as it is. Further, there is no disclosure in the document regarding raising the surface tension of the ink to an optimum range for inkjet ejection to improve ejection stability. Generally, siloxane is a material having a low surface tension that is known as a leveling agent for lowering the surface tension. It is extremely difficult to raise the surface tension of a liquid having such a low surface tension, and the surface tension is raised. It can be said that there is little knowledge about the additive to be adjusted in this way, and no technique has been disclosed so far that solves the problem of surface tension of such a liquid.

Therefore, it is expected that an inkjet ink having high ejection stability, which can provide a protective layer by directly coating an organic electronic device by using inkjet printing, will appear.

U.S. Patent Application No. 2017/207419 International Publication No. 2016/170893 JP-A-2007-326994

The present invention has been made in view of the above problems and situations, and the problem to be solved thereof can be directly applied when forming a protective layer containing a liquid silicone rubber on an organic electronic device by inkjet printing. Inkjet ink with high ejection stability, which does not damage the organic electronic device and can obtain high gas barrier properties even if a sealing layer is provided directly on the protective layer, and a film forming method using the ink. The purpose of the present invention is to provide an ink coating film, a cured silicone rubber film, and a multifunctional film.

In the process of investigating the cause of the above problem in order to solve the above problem, the present inventor uses an inkjet ink containing a specific addition-polymerized polysiloxane and a specific additive to perform inkjet printing on an organic electronic device. When forming a protective layer containing a cured silicone rubber, it can be applied directly, there is no damage to the organic electronic device, and even if a sealing layer is provided directly on the protective layer, it has high gas barrier properties. It has been found that an ink jet ink having high ejection stability, a film forming method using the ink jet ink, an ink coating film, a cured silicone rubber film, and a multifunctional film can be obtained.

That is, the above problem according to the present invention is solved by the following means.

1. 1. Inkjet ink containing liquid silicone rubber
It contains at least a liquid silicone rubber (A) having a unit structure represented by the general formula (A), a catalyst (B), a volatile siloxane diluent (C), and a surface tension adjusting agent (D). Ink for inkjet characterized by that.

(In the formula, R represents an unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bond having 1 to 8 carbon atoms. R'represents a substituent synonymous with R, and R R'may be the same or different. N represents an integer greater than or equal to 1.)

2. The liquid silicone rubber (A) has a _{first polysiloxane (a 1) having two or more alkenyl groups in the molecule and a second} polysiloxane (a 2) having two or more hydrosilyl groups in the molecule. ), The ink for inkjet according to item 1, wherein the catalyst (B) is a hydrosilylation catalyst.

3. 3. The ink jet ink according to item 1 or 2, wherein the surface tension at 20 ° C. after adding the surface tension adjusting agent (D) is in the range of 20 to 35 mN / m.

4. The ink jet ink according to any one of items 1 to 3, wherein the volatile siloxane diluent (C) contains a small molecule siloxane compound.

5. The ink jet ink according to any one of items 1 to 4, wherein the surface tension adjusting agent (D) is a photocurable polyfunctional monomer.

6. The ink jet ink according to any one of items 1 to 5, wherein the surface tension adjusting agent (D) is a metal oxide fine particle.

7. The ink jet ink according to Item 6, wherein the metal oxide fine particles are silicon oxide particles or titanium oxide particles.

8. A film forming method comprising a step of forming an ink coating film on a substrate using the inkjet ink according to any one of items 1 to 7.

9. Item 8 is characterized by having a step of drying the ink coating film to remove a volatile siloxane diluent, and then a step of forming a cured silicone rubber film by irradiating the ink coating film with ultraviolet rays. The film forming method according to.

10. The film forming method according to item 8 or 9, further comprising a step of forming a multifunctional film by directly ejecting the inkjet ink onto an organic electronic device.

11. An ink coating film formed by using the inkjet ink according to any one of items 1 to 7.

12. A cured silicone rubber film formed by using the inkjet ink according to any one of items 1 to 7.

13. A multifunctional film formed by using the inkjet ink according to any one of items 1 to 7.

According to the above means of the present invention, when a protective layer containing a cured silicone rubber is formed on an organic electronic device by inkjet printing, it can be applied directly, there is no damage to the organic electronic device, and the protective layer is further formed. Provided are inkjet inks with high ejection stability, which can obtain high gas barrier properties even if a sealing layer is directly provided on the top, a film forming method using the ink, an ink coating film, a cured silicone rubber film, and a multifunctional film. can do.

Although the mechanism of expression or mechanism of action of the effects of the present invention has not been clarified, it is inferred as follows.

Conventionally, inkjet inks containing liquid silicone rubber, which have no concern about by-products that adversely affect organic electronic devices, have been known, but since the surface tension of the liquid is low, stable inkjet ejection cannot be expected, and the liquid Since dripping occurred and the discharge stability was lacking, it was not at the practical level as it was. Further, Patent Document 3 does not disclose that the surface tension of the discharged liquid is raised to the optimum range for inkjet to improve the discharge stability, and it is difficult to actually raise the surface tension of the liquid having a low surface tension. It was good to say that there was almost no knowledge about additives that increase surface tension.

The inkjet ink of the present invention is an inkjet ink containing a specific liquid silicone rubber and a specific additive, particularly a specific surface tension adjusting agent, by adjusting the surface tension of the ink to an optimum level for the inkjet method. , The problem of discharge stability is solved. The inkjet ink can be directly applied when forming a protective layer on an organic electronic device by inkjet printing, and a low molecular weight diffusion component (monomer, a monomer, etc.) from an upper coating film (smooth layer, coating barrier layer, etc.) If there is no suppression of diffusion of the initiator (initiator, solvent), damage to the electrodes and organic layer due to plasma when forming the sealing layer by CVD, and the protective layer also serves as a smooth layer, the protection is on top of the protection. It is possible to provide an ink jet ink having high ejection stability, which can obtain high gas barrier properties even if a direct sealing layer is provided.

Schematic diagram when a protective layer according to the present invention is formed on an organic electronic device. Schematic diagram when another protective layer according to the present invention is formed on an organic electronic device. Schematic diagram showing an example of an inkjet printing method Schematic perspective view showing an inkjet head applicable to the present invention Bottom view of inkjet head Schematic diagram showing an example of a vacuum plasma CVD apparatus used for forming a sealing layer.

The ink for inkjet of the present invention is an ink for inkjet containing a liquid silicone rubber, and includes at least a liquid silicone rubber (A) having a unit structure represented by the general formula (A) and a catalyst (B). , A volatile siloxane diluent (C) and a surface tension modifier (D). This feature is a technical feature common to or corresponding to the following embodiments.

In an embodiment of the present invention, from the viewpoint of exhibiting the effect of the present invention, the liquid silicone rubber (A) has an intramolecular first polysiloxane (a ₁ ) having two or more alkenyl groups in the molecule. It is preferable that the catalyst (B) is a hydrosilylation catalyst, which comprises a mixture of _{a second} polysiloxane (a 2) having two or more hydrosilyl groups.

Further, in the inkjet ink of the present invention, the surface tension at 20 ° C. after the addition of the surface tension adjusting agent (D) is within the range of 20 to 35 mN / m from the viewpoint of enhancing ejection stability. ,preferable.

Further, it is preferable that the volatile siloxane diluent (C) contains a small molecule siloxane compound from the viewpoint of high volatility and reduction of the residual diluent when the coating film is dried.

The surface tension adjusting agent (D) is preferably a photocurable polyfunctional monomer, and the metal oxide fine particles have a high effect of adjusting the surface tension without affecting other materials. preferable. Further, it is preferable that the metal oxide fine particles are silicon oxide particles or titanium oxide particles.

The film forming method using the inkjet ink of the present invention is characterized by having a step of forming an ink coating film on a substrate using the inkjet ink.

Further, the electronic device and the upper layer include a step of drying the ink coating film to remove the volatile siloxane diluent, and then a step of forming a cured silicone rubber film by irradiating the ink coating film with ultraviolet rays. It is preferable from the viewpoint of avoiding adverse effects on.

Further, according to the film forming method of the present invention, a multifunctional film can be formed by directly ejecting the inkjet ink onto an organic electronic device. As the multifunctional film, first, a thin film having a common protective layer and a smooth layer is exemplified, which leads to a reduction in the number of layers.

By using the inkjet ink of the present invention, an ink coating film, a cured silicone rubber film and a multifunctional film can be obtained.

Hereinafter, the present invention, its constituent elements, and modes and modes for carrying out the present invention will be described in detail. In the present application, "~" is used to mean that the numerical values described before and after the value are included as the lower limit value and the upper limit value.

<< Outline of Inkjet Ink of the Present Invention >>
The ink for inkjet of the present invention is an ink for inkjet containing a liquid silicone rubber, and includes at least a liquid silicone rubber (A) having a unit structure represented by the following general formula (A) and a catalyst (B). , A volatile siloxane diluent (C) and a surface tension modifier (D).

In the formula, R represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms and having no aliphatic unsaturated bond. R'represents a substituent synonymous with R, and R and R'may be the same or different. n represents an integer of 1 or more.

Silicone rubber is generally commercially available in the form of a liquid, and is a rubber-like resin that is cured by the polymerization reaction of silicone by adding a catalyst. It is roughly classified into an addition reaction type and a condensation reaction type according to the type of reaction. The silicone rubber according to the present invention may be of either type, but an addition reaction type that does not generate outgas is particularly preferable. The addition reaction type is polymerized by adding a hydrosilyl group to an carbon-carbon double bond, and the silicone rubber formed by the addition reaction is called an addition reaction type silicone rubber or an addition polymerization type silicone rubber.

The layer structure when the protective layer according to the present invention is formed on an electronic device using the inkjet ink of the present invention is shown.

FIG. 1 is a schematic view when a protective layer according to the present invention is formed on an electronic device.

In FIG. 1A, the ink for inkjet of the present invention is ejected from an inkjet head onto an electronic device 1 to form a protective layer 2, a smooth layer 3 is provided on the protective layer 2, and the ink is further subjected to, for example, CVD. The sealing layer 4 which is an inorganic film is formed.

FIG. 1B is a schematic view when the protective layer also serves as the smoothing layer and forms a common layer. A protective layer 2 having a smoothing function is formed on the electronic device 1 and directly sealed on the protective layer 2. A stop layer 4 is formed. In this case, the number of layers and the number of production steps can be reduced. Further, the surface tension of the ink for inkjet of the present invention is at least the liquid silicone rubber (A), the catalyst (B), and the volatile siloxane diluent (C). And, in the composition in which the surface tension adjusting agent (D) is mixed, it is preferable to prepare the composition in the range of 20 to 35 mN / m at 20 ° C., but more preferably in the range of 24 to 30 mN / m. ..

An example of the method for measuring the surface tension is given below.

<Surface tension measurement method>
The surface tension of the inkjet ink of the present invention is measured by the willmy method (plate method). More specifically, it is calculated by contacting the willmy plate with the liquid sample to give strain and measuring the force of pulling the willmy plate into the liquid. As the measuring device, Leosurf, which is a dynamic surface tension measuring device manufactured by UBM Co., Ltd., is used.

The surface tension is measured after the ink liquid temperature and room temperature are kept constant. Specifically, the ink is left in an environment of room temperature (20 ° C.), and the surface tension of the ink is measured when the liquid temperature of the ink reaches 20 ° C.

[1] Composition of Ink for Ink Ink The ink for inkjet of the present invention is an ink for inkjet containing a liquid silicone rubber, and has at least a liquid silicone rubber having a unit structure represented by the general formula (A). It is characterized by containing A), a catalyst (B), a volatile siloxane diluent (C), and a surface tension adjusting agent (D) capable of increasing the surface tension of the liquid before the addition. ..

The liquid silicone rubber (A) has a _{first polysiloxane (a 1) having two or more alkenyl groups in the molecule and a second} polysiloxane (a 2) having two or more hydrosilyl groups in the molecule. ) Is preferably composed of a mixture of.

_{(1) A first polysiloxane (a 1} ) having two or more alkenyl groups in the molecule.
The first polysiloxane (a ₁ ) is a base polymer contained in the ink jet ink of the present invention, and is an organopolysiloxane having two or more alkenyl groups in the molecule. The organopolysiloxane includes, for example, an organopolysiloxane having an alkenyl group bonded to a silicon atom at both ends of the molecular chain or the side chain of the molecular chain (in the middle of the molecular chain) (particularly, from the repetition of the diorganosiloxane unit in the main chain). As a linear diorganopolysiloxane in which both ends of the molecular chain are sealed with a triorganosyloxy group), those represented by the following general formula (1) are preferably used.

In the formula, R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms and having no aliphatic unsaturated bond. R ² is an alkenyl group having 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms. R ³ is ^{a hydrocarbon group synonymous with R 1} or R ² , which may be the same or different. m represents an integer of 2 to 50 when ^{R 3} and R ^{1 are synonymous or identical hydrocarbon groups.} When R ³ is a hydrocarbon group synonymous with or the same as ^{R 2, it represents an integer of 0 to 50.} n is an integer from 0 to 1000.

Examples of R ¹ include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, hexyl group and cyclohexyl group and cycloalkyl group; aryl group such as phenyl group; aralkyl group such as benzyl group; chloromethyl group. , 3-Chloropropyl group, 3,3,3-trifluoropropyl group and other halogen-substituted hydrocarbon groups, preferably methyl group, phenyl group, 3,3,3-trifluoropropyl group and the like. It is preferably a methyl group. Examples of R ² include an alkyl group such as a vinyl group, an allyl group, a butenyl group, a cyclopentenyl group and a cyclohexenyl group, and a cycloalkenyl group, and a vinyl group is particularly preferable.

m is an integer of 2 to 50, preferably 2 to 20, more preferably 2 to 10 ^{when R 3} is a hydrocarbon group synonymous with or identical to R ^1. When R ³ is ^{a hydrocarbon group synonymous with or the same as R 2,} it is an integer of 0 to 50, preferably 0 to 20, and more preferably 1 to 10. n is an integer of 0 to 1000, preferably an integer of 20 to 500, more preferably an integer of 20 to 200, and particularly preferably an integer of 50 to 100.

Examples of the liquid silicone rubber (A) include the following compounds (1) to (3).

(In the formula, m1 is an integer of 2 to 50. m2 is an integer of 1 to 50. n is an integer of 0 to 1000.)
_{(2) A second polysiloxane (a 2} ) having two or more hydrosilyl groups in the molecule.
The second polysiloxane (a ₂ ) is an organohydrogen polysiloxane having two or more hydrosilyl groups (SiH groups) in the molecule, and is a cross-linking agent for the liquid silicone rubber (A). In this case, the molecular structure is not particularly limited, and various types such as linear, cyclic, branched, and three-dimensional network structures can be used, but two or more, preferably three, are used in one molecule. It is necessary to have a hydrogen atom (hydrosilyl group represented by SiH) bonded to the above silicon atom, and it is desirable to have usually 2 to 200, more preferably about 3 to 100 SiH groups. Further, those having 2 to 300 silicon atoms (or degree of polymerization) in one molecule, particularly about 3 to 150, are preferably used.

The organohydrogenpolysiloxane includes, for example, a triorganosyloxy group at both ends of the molecular chain represented by the following general formula (2) having a hydrosilyl group at both ends of the molecular chain and / or the side chain of the molecular chain (in the middle of the molecular chain). Blocked Organohydrogenpolysiloxane, Triorganosiloxy Group Blocked at Both Ends of Molecular Chain Organohydrogensiloxane / Diorganosiloxane Copolymer, Diorganohydrogensiloxy Group Blocked at Both Ends of Molecular Chain Diorganopolysiloxane, Diorgano at Both Ends of Molecular Chain Hydrogensiloxy group-blocked organohydrogenpolysiloxane, molecular chain both-terminal diorganohydrogensiloxy group-blocked organohydrogensiloxane / diorganosiloxane copolymer, linear chain such as 1,1,3,3-tetraorganodisiloxane A state organohydrogenpolysiloxane (here, the organo group means a monovalent hydrocarbon group having no aliphatic unsaturated group) or the like is preferable.

Wherein, R ⁴ is preferably unsubstituted or substituted C1-8 monovalent hydrocarbon group having no aliphatic unsaturated bond. R ⁵ is a hydrogen atom or ^{a hydrocarbon group synonymous with R 4,} and may be the same or different. p is an integer from 0 to 100. q is an integer from 0 to 100 when ^{R 5 is a hydrogen atom.} When R ⁵ is ^{a hydrocarbon group synonymous with or the same as R 4} , it is an integer of 2 to 100.

Examples of R ⁴ include methyl group, ethyl group, propyl group, butyl group, hexyl group, an alkyl group or a cycloalkyl group such as a cyclohexyl group; chloromethyl group; aralkyl group such as benzyl group; an aryl group such as a phenyl group , 3-Chloropropyl group, 3,3,3-trifluoropropyl group and other halogen-substituted hydrocarbon groups, preferably methyl group, phenyl group, 3,3,3-trifluoropropyl group and the like. It is preferably a methyl group. p is an integer from 0 to 100, preferably 0 to 40. Further, q is an integer of 0 to 100, preferably 1 to 40 when ^{R 5 is a hydrogen atom.} When R ⁵ is ^{a hydrocarbon group synonymous with or the same as R 4,} it is an integer of 2 to 100, preferably 3 to 40.

Examples of the second polysiloxane (a ₂ ) include the following compounds (4) to (6).

(In the formula, p is an integer from 0 to 100. Q1 is an integer from 2 to 100. Q2 is an integer from 0 to 100.)
The composition amount of the _second polysiloxane (a 2) is such that 1 mol of the alkenyl group bonded to the silicon atom of the _first polysiloxane (a 1) has a SiH group in the _{second polysiloxane (a 2).} It is preferable that the amount (that is, the hydrogen atom bonded to the silicon atom) is 0.5 to 20 mol, particularly 1.5 to 12 mol. Alternatively, the amount may be 0.1 to 100 parts by mass, particularly 0.1 to 50 parts by mass with respect to 100 parts by mass of the _first polysiloxane (a 1).

As the liquid silicone rubber (A) having the unit structure represented by the general formula (A), a commercially available product can also be used, and KER-4500, KER-4600, KER-4410, KER4690-A / B, KER- 4691-A / B, KER-4530, KER-4531, KE-1031-A / B, KE-103, KE-106F, KE-109E-A / B, KE-1282-A / B, KE-1283- A / B, KE-1204-A / B (above, manufactured by Shinetsu Silicone), TSE3250 (manufactured by Momentive), TSCE4000, TSCE5000, TSCE6000, TSCE7000, TSCE8000 (above, manufactured by Tomita Matex) and the like can be mentioned. ..

(3) Catalyst (B)
The catalyst (B) is preferably a hydrosilylation catalyst.

The catalyst (B) is a catalyst for accelerating curing of the composition by an addition reaction (hydrosilylation), and well-known catalysts for hydrosilylation reactions such as platinum-based catalysts, rhodium-based catalysts, and palladium-based catalysts are exemplified. .. In particular, platinum-based catalysts such as platinum fine powder, platinum black, platinum-supported silica fine powder, platinum-supported activated carbon, platinum chloride acid, alcohol solution of platinum chloride acid, platinum olefin complex, and platinum alkenylsiloxane complex have a high reaction rate. It is preferable because it is good.

Examples of the platinum-based catalyst, which is the preferred catalyst (B), include an alcohol solution of chloroplatinic acid. This is obtained by dissolving platinum chloride (IV) acid hexahydrate in ethanol, isopropanol (IPA), n-butanol, 2-ethylhexyl alcohol, etc., and the metal platinum concentration is about 0.1 to 5% by mass, preferably about 0.1 to 5% by mass. It is adjusted to 0.5 to 2% by mass. Further, a platinum complex compound solution obtained by neutralizing these platinum chloride alcohol solutions, coordinating the diene compound, and substituting with an appropriate solvent is also preferably used. Examples of this diene are 1,3-butadiene, 1,5-hexadiene, 1,9-decadien, cyclopentadiene, 1,3-cyclohexadiene, vinyl norbornene, 1,3-divinyl-1,1,3. Examples thereof include 3-tetramethyldisiloxane and 1,5-divinyl-1,1,3,3,5,5-hexamethyltrisiloxane. Examples of the solvent include toluene, xylene, hexane, heptane, acetone, methyl ethic ketone (MEK), methyl isobutyl ketone (MIBK), ethyl acetate, butyl acetate and the like, in addition to the above alcohols, and organopolysiloxane. (Silicone oil) and the like can also be mentioned.

The blending amount of the catalyst (B) is the amount of the catalyst, and is usually 1 to 1000 ppm, particularly 5 to 200 ppm, as a platinum metal with respect to the total amount of the liquid silicone rubber (A).

(4) Volatile siloxane diluent (C)
The volatile siloxane diluent (C) is highly volatile and the amount of residual diluent can be reduced when the coating film is dried. Therefore, it is preferable that the volatile siloxane diluent contains a low molecular weight siloxane compound. ..

The volatile siloxane diluent (C) is not particularly limited, and examples thereof include chain siloxanes (for example, alkyl siloxanes), cyclic siloxanes, and polyether-modified siloxanes. The volatile siloxane diluent (C) has a property of not causing damage even if it diffuses into an organic electronic device.

Examples of the chain siloxane include low molecular weight volatile siloxane compounds such as hexamethyldisiloxane, dimethicone, and methyltrimethicone, and examples of the cyclic siloxane include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane. And so on.

As the volatile siloxane diluent (C), it is preferable to dry the ink coating film to remove the volatile siloxane diluent. The molecular weight of the small molecule siloxane is preferably 2000 or less, more preferably 1000 or less, and particularly preferably 800 or less.

The boiling point of the volatile siloxane is preferably 80 ° C to 250 ° C, more preferably 90 ° C to 210 ° C. If the boiling point is lower than 80 ° C, it becomes difficult to handle at normal temperature and pressure, and if it is higher than 250 ° C, it becomes difficult to remove it by drying the coating film, which is not preferable.

It is preferable that the content (mass) of the volatile siloxane diluent (C) is within the range of 1 to 30 times that of the polysiloxane, from the viewpoint of adjusting the viscosity of the polysiloxane-containing coating liquid. More preferably, it is in the range of 2 to 15 times.

(5) Surface tension adjuster (D)
The surface tension modifier (D) is preferably a photocurable polyfunctional monomer or metal oxide fine particles. (5.1) Photocurable polyfunctional monomer The photocurable monomer is a photocurable functional group (for example,). (Meta) means a functional group such as an acrylate group or a vinyl group that can be cured by advancing a polymerization reaction or a cross-linking reaction by light irradiation.) It means a monomer. The photocurable polyfunctional monomer is preferably a non-silicone photocurable monomer having a photocurable functional group.
The photocurable monomer includes a monofunctional monomer and a polyfunctional monomer, but the one effectively used in the present invention is a polyfunctional monomer from the viewpoint of more easily forming a crosslinked structure. However, a mixture with a monofunctional monomer may be used as long as the effect is not impaired. As used herein, the term "monofunctional monomer" means a monomer having one photocurable functional group. As used herein, the term "polyfunctional monomer" means a monomer having two or more photocurable functional groups.

The photocurable polyfunctional monomer (hereinafter, also referred to as a photocurable monomer) preferably has 2 to 30 photocurable functional groups in consideration of reactivity and the like, and preferably has 2 to 20 photocurable functional groups. It is more preferable to have 2 to 5 pieces, and even more preferably to have 2 to 5 pieces.

Examples of the photocurable monomer include the following monomers. That is, the photocurable monomer is an aromatic compound having 6 to 20 carbon atoms having a substituted or unsubstituted vinyl group; an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and 6 to 6 carbon atoms. An unsaturated carboxylic acid ester having 20 aromatic groups or a hydroxy group and an alkyl group having 1 to 20 carbon atoms; an unsaturated carboxylic acid ester having an aminoalkyl group having 1 to 20 carbon atoms; a saturated carboxylic acid ester having 1 to 20 carbon atoms. Or vinyl ester of unsaturated carboxylic acid; glycidyl ester of unsaturated carboxylic acid having 1 to 20 carbon atoms; vinyl cyanide compound; unsaturated amide compound; monoalcohol or polyhydric alcohol monofunctional (meth) acrylate; monoalcohol or polyalcohol It may be one or more of the polyfunctional (meth) acrylates of the valent alcohol. Among them, in order to further improve the effect of the present invention, the photocurable monomer consists of a group consisting of a polyalkylene glycol di (meth) acrylate and a monofunctional or polyfunctional (meth) acrylate of a monoalcohol or a polyhydric alcohol. It is preferred that it contains at least one selected. The "multivalent alcohol" is an alcohol having two or more hydroxy groups, preferably having 2 to 20 hydroxy groups, and even more preferably 2 to 10 hydroxy groups. It is particularly preferable to have ~ 6. As used herein, the term "polyfunctional (meth) acrylate" means a monomer having two or more (meth) acrylates.

The photocurable monomer is at least one selected from the group consisting of monoalcolate (meth) acrylates having 1 to 30 carbon atoms and polyalkylene glycol di (meth) acrylates among the above-mentioned monomers; With at least one selected from the group consisting of di (meth) acrylates of 20 diols, tri (meth) acrylates of triols having 3 to 20 carbon atoms, and tetra (meth) acrylates of tetraols having 4 to 20 carbon atoms; It is preferable that the mixture contains. In the present specification, "monoalcohol (meth) acrylate" refers to an ester of monoalcohol and (meth) acrylic acid. Further, in the present specification, the "(meth) acrylate of a polyhydric alcohol" refers to an ester of a polyhydric alcohol and (meth) acrylic acid. The carbon number refers to the carbon number of monoalcohol, diol, triol, and tetraol, respectively.

The viscosity of the composition can be reduced by using a polyalkylene glycol di (meth) acrylate.

The following monomers can be used as the photocurable monomer. That is, as the photocurable monomer, an aromatic compound having an alkenyl group containing a vinyl group such as styrene, alpha-methylstyrene, vinyltoluene, vinylbenzyl ether, and vinylbenzylmethyl ether; and methyl (meth) having 6 to 20 carbon atoms. ) Acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate , Undecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate and other unsaturated carboxylic acid esters; 2-aminoethyl (meth) ) Unsaturated carboxylic acid aminoalkyl ester such as acrylate and 2-dimethylaminoethyl (meth) acrylate; Saturated or unsaturated carboxylic acid vinyl ester such as vinyl acetate and vinyl benzoate; 1 to 20 carbon atoms such as glycidyl (meth) acrylate Acrylate glycidyl ester of unsaturated carboxylic acid; vinyl cyanide compound such as (meth) acrylonitrile; unsaturated amide compound such as (meth) acrylamide may be contained.

Among the above, it is preferable to use the following compounds in order to further improve the effect of the present invention. The polyalkylene glycol di (meth) acrylate includes diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, poly (ethylene glycol) di (meth) acrylate, and tri (propylene glycol). It is preferably at least one selected from the group consisting of glycol) di (meth) acrylate and poly (propylene glycol) di (meth) acrylate.

The (meth) acrylate of the polyhydric alcohol is 1,8-octanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol diacrylate, 1,11-. It is preferable to select from the group consisting of undecanediol di (meth) acrylate, 1,12-dodecanediol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetraacrylate. ..

Further, in order to further improve the effect of the present invention, the photocurable monomer preferably contains tetraethylene glycol di (meth) acrylate and 1,10-decanediol di (meth) acrylate, and further, pentaerythritol tetra. It is more preferable to contain (meth) acrylate.

In a specific example, the photocurable monomer may contain one or more of monoalcoholic or polyhydric alcohol monofunctional (meth) acrylates; monoalcohol or polyhydric alcohol polyfunctional (meth) acrylates.

More specifically, the photocurable monomers are methyl (meth) acrylate, ethyl (meth) crylate, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, and decanyl (meth). ) Mono (meth) acrylate of monoalcohol having 1 to 30 carbon atoms such as acrylate, undecanyl (meth) acrylate, dodecyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate; ethylene Glycoldi (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tri (propylene glycol) di (meth) acrylate, poly (propylene glycol) di ( Monoalkylene glycol di (meth) acrylates or polyalkylene glycol di (meth) acrylates or mixtures thereof, including meta) acrylates, etc .; 1,4-butanediol di (meth) acrylates, 1,6-hexanediol di (meth) acrylates, etc. ) Acrylate, octanediol di (meth) acrylate, nonanediol di (meth) acrylate, decanediol di (meth) acrylate, undecanediol di (meth) acrylate, dodecanediol di (meth) acrylate, neopentyl glycol di (meth) Di (meth) acrylates of diols, triols, tetraols, pentaols, or hexaols having 2 to 20 carbon atoms, including acrylates, pentaerythritol di (meth) acrylates, dipentaerythritol di (meth) acrylates, etc. Triol, tetraol, pentaol, or hexaol tri (meth) having 3 to 20 carbon atoms including methylolpropantri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, etc. Acrylate; Tetra (meth) acrylate of tetraol, pentaol or hexaol containing 4 to 20 carbon atoms including pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate; dipentaerythritol penta (meth) Pentaol or hexaol penta (meth) acrylate containing 4 to 20 carbon atoms including acrylate, etc .; Hexaol hexa (meth) acrylate having 4 to 20 carbon atoms including entaerythritol hexa (meth) acrylate; bisphenol A di (meth) acrylate; novolak epoxy (meth) acrylate and the like may be contained.

The photocurable monomer may be contained alone or in combination of two or more. The photocurable monomer may be contained alone or in combination of two or more of the same type.

The photocurable monomer preferably contains one or more of polyfunctional (meth) acrylates, for example, bifunctional (meth) acrylates, trifunctional (meth) acrylates, and tetrafunctional (meth) acrylates. It is preferable from the viewpoint of adjusting to.

The photocurable monomer may contain a mixture of one or more of a) bifunctional (meth) acrylate; and b) trifunctional (meth) acrylate and tetrafunctional (meth) acrylate.

Further, in an example of the present invention, the photocurable monomer may contain one or more of the following i), ii), iii), iv) and v):
i) Mono (meth) acrylate of monoalcohol with 1 to 30 carbon atoms,
ii) Monoalkylene glycol di (meth) acrylate or polyalkylene glycol di (meth) acrylate or a mixture thereof,
iii) Di (meth) acrylates of diols, triols, tetraols, pentaols, or hexaols having 2 to 20 carbon atoms.
iv) Triol, tetraol, pentaol, or hexaol tri (meth) acrylates with 3 to 20 carbon atoms,
v) Tetraol, pentaol or hexaol tetra (the above i), ii), iii), iv) and v) having 4 to 20 carbon atoms can be used alone or in combination of two or more ink compositions. May be included in.

The photocurable monomer is preferably contained in the ink composition in the range of 0.5 to 50% by mass, more preferably in the range of 2 to 20% by mass.

(5.2) Metal oxide fine particles The surface tension adjusting agent (D) preferably contains metal oxide particles. The metal oxide particles may be metal oxide fine particles whose surface has been modified by a predetermined surface modifier.

The metal oxide fine particles may be metal oxides including transition metals, for example, silicon oxide, magnesium oxide, zinc oxide, lead oxide, aluminum oxide (alumina), tantalum oxide, indium oxide, bismuth oxide, and oxidation. Examples thereof include yttrium, cobalt oxide, copper oxide, manganese oxide, selenium oxide, iron oxide, zirconium oxide, germanium oxide, tin oxide, titanium oxide, niobium oxide, molybdenum oxide and vanadium oxide.

The untreated metal oxide fine particles are preferably silicon oxide particles or titanium oxide particles from the viewpoint of adjusting the surface tension.

As the untreated metal oxide fine particles, those produced by a general production method such as a vapor phase method, a chlorine method, a sulfuric acid method, a plasma method, or an electrolysis method can be used.

The number average primary particle size of the untreated metal oxide fine particles is preferably in the range of 1 to 300 nm, and more preferably in the range of 3 to 100 nm. When the number average primary particle size is 1 nm or more, the surface tension adjusting ability is sufficient, and when the number average primary particle size is 300 nm or less, the dispersibility is good and it is difficult to settle in the coating liquid. In addition, the particles do not hinder the photocuring of the ink coating film, and the abrasion resistance is improved.

The number average primary particle size of the untreated metal oxide fine particles is a photographic image (aggregated particles) obtained by taking a 10000 times magnified photograph with a scanning electron microscope (manufactured by JEOL Ltd.) and randomly capturing 300 particles with a scanner. (Excluded) is an automatic image processing analyzer (trade name: "LUZEX AP", manufactured by JEOL Ltd.) software version Ver. The numerical average primary particle size is calculated using 1.32.

The surface modifier for producing the surface-modified metal oxide fine particles is not particularly limited, and preferably contains Si. The amount of surface modification is determined by heat-treating the surface-modified metal oxide fine particles at 550 ° C. for 3 hours, quantitatively analyzing the strong heat residue by fluorescent X-rays, and converting the amount of Si into molecular weight.

Specifically, the surface is preferably surface-modified with a silane coupling agent, for example, vinylsilazane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, trimethylalkoxysilane, dimethyldialkoxysilane, methyltrialkoxysilane, hexa. Examples thereof include methyldisilazane, and trimethylmethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, hexamethyldisilazane and the like are preferably used.

For surface modification, a wet media dispersion type apparatus can be used. The wet media dispersion type device is a device in which beads are filled as media in a container, and a stirring disk mounted perpendicular to the rotation axis is rotated at high speed to crush and pulverize and disperse agglomerated particles of metal oxide fine particles. It is an apparatus capable of executing the process, and there is no particular problem as long as the untreated metal oxide fine particles are sufficiently dispersed when the untreated metal oxide fine particles are surface-modified and the surface can be modified. However, various styles such as vertical / horizontal type, continuous type / batch type, and the like can be adopted. Specifically, a sand mill, an ultra visco mill, a pearl mill, a Glen mill, a dyno mill, an agitator mill, a dynamic mill and the like can be used. These dispersion-type devices are finely pulverized and dispersed by impact crushing, friction, shearing, shear stress, etc. using a pulverizing medium (media) such as balls and beads. As the beads used in the dispersion type apparatus, balls made of glass, alumina, zircon, zirconia, steel, flint stone or the like can be used, but those made of zirconia or zircon are particularly preferable. The size of the beads is usually about 1 to 2 mm in diameter, but in this embodiment, it is preferable to use beads having a diameter of about 0.3 to 1.0 mm.

The metal oxide fine particles are preferably contained in the range of 0.1 to 50 parts by volume, more preferably in the range of 1 to 30 parts by volume with respect to the volatile siloxane diluted solution.

(6) Other Compositions In addition to the above description, the inkjet ink of the present invention has, if necessary, emission stability, print head and ink cartridge compatibility, storage stability, image storage, and other performances. Various known additives, viscosity modifiers, specific resistance modifiers, film forming agents, ultraviolet absorbers, antioxidants, anti-fading agents, anti-corrosive agents, anti-corrosive agents, etc. are appropriately selected according to the purpose of improvement. Can be used.

(7) Preparation of Inkjet Ink In the preparation of the ink for inkjet of the present invention, at least the first polysiloxane (a ₁ ) having two or more alkenyl groups in the molecule and two or more hydrosilyls in the molecule are prepared. After mixing the second polysiloxane (a ₂ ) having a group, the hydrosilylation catalyst (B), the volatile siloxane diluent (C), and the surface tension adjuster (D), foreign substances are removed through a filter. By doing so, it can be used as an ink for inkjet.

The surface tension of the inkjet ink of the present invention having the above configuration is in the range of 20 to 35 mN / m at 20 ° C., particularly in the range of 24 to 30 mN / m, according to the above-mentioned measuring method. preferable. If the surface tension is less than 20 mN / m, ink adheres to the nozzle plate of the inkjet head, and it becomes difficult to form meniscus in the nozzle, and the ejection stability deteriorates. Further, if the surface tension exceeds 35 mN / m, the desired wettability to the substrate cannot be obtained. The viscosity is preferably in the range of 1 to 50 mPa · s, more preferably in the range of 2 to 20 mPa · s. If the viscosity exceeds the above range, the ejection property of the inkjet is lowered.

[2] Inkjet Printing Method The method for forming a protective layer film according to the present invention is characterized by including a step of forming an ink coating film on a substrate using the inkjet ink of the present invention.

Further, it is preferable to have a step of drying the ink coating film to remove the volatile siloxane diluent, and then a step of forming a cured silicone rubber film by irradiating the ink coating film with ultraviolet rays.

Further, it is preferable to have a step of forming a multifunctional film by directly ejecting the inkjet ink directly onto an organic electronic device.

The multifunctional film is a multifunctional film obtained when a metal oxide is used as an adjusting agent for increasing surface tension, in addition to the protective layer for standardizing the protective layer and the smooth layer, which is the main object of the present invention. One of the functions of the sex film is expected to be a "light scattering function", which is effective for organic light emitting element devices. In addition, the functions of the "multifunctional film" include the above-mentioned functions such as flattening, protection from process damage during lamination, and stress relaxation. For example, UV absorption can be achieved by adding a UV absorber or an infrared absorber. Further functions and infrared absorption functions can be added.

The layer thickness of the protective layer, which is the ink coating film according to the present invention, after drying is preferably in the range of 0.1 to 10 μm, more preferably in the range of 0.2 to 7 μm. Therefore, it is preferable that the wet layer thickness of the ink coating film is appropriately adjusted in consideration of the layer thickness after drying.

Hereinafter, the inkjet head used in the inkjet printing method, the ejection conditions for ink droplets, the inkjet printing method and the apparatus will be described with reference to the drawings.

(Inkjet head)
The inkjet head used in the inkjet printing method may be an on-demand method or a continuous method. The discharge method includes an electric-mechanical conversion method (for example, single cavity type, double cavity type, bender type, piston type, shared mode type, shared wall type, etc.) and an electric-heat conversion method (for example, thermal). Specific examples include an inkjet type, a bubble jet (registered trademark) type, etc.), an electrostatic attraction method (for example, an electric field control type, a slit jet type, etc.), and a discharge method (for example, a spark jet type, etc.). However, any discharge method may be used. Further, as the printing method, a serial head method, a line head method, or the like can be used without limitation.

(Ink droplet size)
In forming each constituent layer, the volume of ink droplets ejected from the inkjet head is preferably in the range of 0.5 to 100 pL. It is more preferably in the range of 2 to 20 pL from the viewpoint that the coating unevenness of the cambium is small and the printing speed can be increased. The volume of the ink droplet can be appropriately adjusted to a desired condition by adjusting the applied voltage or the like.

(Printing method)
The printing method by the inkjet printing method includes a one-pass printing method and a multi-pass printing method. The one-pass printing method is a method in which a plurality of inkjet heads are fixedly arranged in a predetermined printing area and printing is performed by one head scan. On the other hand, the multi-pass printing method (also referred to as a serial printing method) is a method of printing a predetermined print area by a plurality of head scans.

In the one-pass printing method, it is preferable to use a wide head in which nozzles are arranged side by side over a width equal to or larger than a desired coating pattern width. When forming a plurality of independent coating patterns whose patterns are not continuous with each other on the same substrate, a wide head having at least the width of each coating pattern may be used.

FIG. 2 is a schematic view showing an example of a film forming method for a protective layer using an inkjet printing method of a one-pass printing method.

FIG. 2 shows an example of a method of forming a protective layer according to the present invention on a substrate F by using an inkjet printer provided with an inkjet head 30. The substrate F may be an organic electronic device.

As shown in FIG. 2, while continuously transporting the flexible base material (F), the ink jet head 30 sequentially ejects ink containing the protective layer forming material as ink droplets to form an ink coating film EL. do.

The inkjet head 30 applicable to the manufacturing method of the present invention is not particularly limited. For example, the ink pressure chamber has a vibrating plate provided with a piezoelectric element, and ink is generated by a pressure change in the ink pressure chamber due to the vibrating plate. It may be a shear mode type (piezo type) head that discharges the liquid, or it has a heat generating element, and the ink liquid is discharged from the nozzle due to a sudden volume change due to the film boiling of the ink liquid due to the heat energy from the heat generating element. It may be a thermal type head to be made to.

An ink jet liquid supply mechanism for ejection is connected to the inkjet head 30. The ink liquid is supplied by the tank 38A. In this example, the tank liquid level is kept constant so that the ink liquid pressure in the inkjet head 30 is always kept constant. As a method, the ink liquid overflows from the tank 38A and is returned to the tank 38B by natural flow. The ink liquid is supplied from the tank 38B to the tank 38A by the pump 31, and the liquid level of the tank 38A is controlled to be stable according to the ejection conditions.

The ink liquid is returned from the pump 31 to the tank 38A after passing through the filter 32. As described above, it is preferable that the ink liquid is passed through a filter medium having an absolute filtration accuracy or a quasi-absolute filtration accuracy of 0.05 to 50 μm at least once before being supplied to the inkjet head 30.

Further, in order to perform cleaning work, liquid filling work, and the like of the inkjet head 30, ink liquid can be forcibly supplied to the inkjet head 30 from the tank 36, and cleaning solvent can be forcibly supplied from the tank 37 to the inkjet head 30 by the pump 39. Such tank pumps may be divided into a plurality of such tank pumps with respect to the inkjet head 30, a branch of a pipe may be used, or a combination thereof may be used. In FIG. 2, the pipe branch 13 is used. Further, in order to sufficiently remove the air in the inkjet head 30, the ink liquid is forcibly sent from the tank 36 to the inkjet 30 by the pump 39, and the ink liquid is discharged from the air bleeding pipe described below to the waste liquid tank 34. I may send it.

FIG. 3 is a schematic external view showing an example of the structure of an inkjet head applicable to the inkjet printing method.

FIG. 3A is a schematic perspective view showing an inkjet head 30 applicable to the present invention, and FIG. 3B is a bottom view of the inkjet head 30.

The inkjet head 30 applicable to the present invention is mounted on an inkjet printer (not shown), and includes a head chip that ejects ink from a nozzle, a wiring board on which the head chip is arranged, and the wiring board. A drive circuit board connected via a flexible substrate, a manifold for introducing ink into the channel of the head chip via a filter, a housing 56 in which the manifold is housed inside, and a bottom opening of the housing 56. The cap receiving plate 57 attached so as to close, the first and second joints 81a and 81b attached to the first ink port and the second ink port of the manifold, and the third ink port attached to the third ink port of the manifold. It includes a joint 82 and a cover member 59 attached to the housing 56. Further, mounting holes 68 for mounting the housing 56 on the printer main body side are formed. 641, 651, 661 and 671 indicate mounting recesses, respectively.

Further, the cap receiving plate 57 shown in FIG. 3B is formed as a substantially rectangular plate whose outer shape is long in the left-right direction corresponding to the shape of the cap receiving plate mounting portion 62, and a plurality of nozzles are formed in the substantially central portion thereof. In order to expose the arranged nozzle plate 61, a long nozzle opening 71 is provided in the left-right direction. Further, regarding the specific structure inside the inkjet head shown in FIG. 3A, for example, FIG. 2 and the like described in Japanese Patent Application Laid-Open No. 2012-140017 can be referred to.

A typical example of the inkjet head is shown in FIG. 3, but in addition to the above, for example, Japanese Patent Application Laid-Open No. 2012-140017, Japanese Patent Application Laid-Open No. 2013-01227, Japanese Patent Application Laid-Open No. 2014-058171 and Japanese Patent Application Laid-Open No. 2014-097644. JP, 2015-142979, 2015-142980, 2016-002675, 2016-002682, 2016-107401, 2017-109476, An inkjet head having the configuration described in JP-A-2017-177626 or the like can be appropriately selected and applied.

After forming the coating film, it is preferable to have a step of drying the coating film to remove the volatile siloxane diluent, and then a step of forming a cured silicone rubber film by irradiating the ink coating film with ultraviolet rays. ..

The drying conditions of the coating are not particularly limited, but it is a preferable example that the coating is carried out in a temperature range of 50 to 250 ° C. for about 10 seconds to 10 minutes. Drying is preferably performed in a heating zone or a heating chamber equipped with a heating device.

In this step, the volatile siloxane diluent is removed from the ink coating. The residual amount of the volatile siloxane diluent is preferably as small as possible, preferably 100 volume ppm or less, more preferably 10 volume ppm or less, and particularly preferably 1 volume ppm or less.

Next, by irradiating the ink coating film with ultraviolet rays, the process shifts to the step of forming a cured silicone rubber film.

Irradiating the ink coating film with ultraviolet rays is preferable because it promotes addition polymerization to form a cured silicone rubber film and improves the smoothness of the thin film surface.

As described above, examples of the means for generating ultraviolet rays in the ultraviolet treatment include metal halide lamps, high-pressure mercury lamps, low-pressure mercury lamps, xenon arc lamps, carbon arc lamps, excimer lamps, UV light lasers, and the like.

Ultraviolet irradiation can be applied to both batch processing and continuous processing, and can be appropriately selected depending on the shape of the base material to be used. When the base material is in the form of a long film, it can be carried out by continuously irradiating the base material with ultraviolet rays in a dry zone provided with the above-mentioned ultraviolet source while transporting the base material. The time required for ultraviolet irradiation depends on the composition and concentration of the base material used and the coating liquid, but is generally 0.1 seconds to 10 minutes, preferably 0.5 seconds to 3 minutes.

The energy coated surface receives, from the viewpoint of forming a uniform and robust film, is preferably 1.0 J / cm ² or more, and more preferably 1.5 J / cm ² or more. Similarly, from the viewpoint of avoiding excessive ultraviolet radiation, it is preferably 14.0J / cm ² or less, more preferably 12.0J / cm ² or less, is 10.0J / cm ² or less Is particularly preferred.

Further, the oxygen concentration when irradiating with ultraviolet rays is preferably 300 to 10000% by volume (1% by volume), more preferably 500 to 5000% by volume.

When irradiated with ultraviolet rays, it is preferable to use a dry inert gas as the gas other than these oxygens, and it is particularly preferable to use dry nitrogen gas from the viewpoint of cost.

For details of these ultraviolet treatments, for example, paragraphs 0055 to 0091 of JP2012-08634, paragraphs 0049 to 0085 of JP2012-006154, paragraphs 0046 to 0074 of JP2011-251460, etc. You can refer to the contents described in.

[3] Sealing layer The sealing layer used in the present invention preferably has a gas barrier property, and has a water vapor transmission rate (25 ± 0.5 ° C., measured by a method according to JIS K 7129-1992). preferably the relative humidity of (90 ± 2)% RH) is 0.01g ^/ (m 2 · 24h) or less of a gas barrier layer, and further, the oxygen permeability measured by the method based on JIS K 7126-1987 degree ^{is, 1 × 10 -3 mL / (} m 2 · 24h · atm) or less, the water vapor permeability, it is ^{1 × 10 -5 g / (m} 2 · 24h) or less of the high gas barrier layer, an electron Preferred for device applications.

The material constituting the sealing layer is not particularly limited as long as it is a material that causes deterioration of electronic devices such as moisture and oxygen but has a function of suppressing infiltration. For example, metal oxides, metal acid carbides, and metal acid nitrides. Inorganic substances such as substances or metal nitrides, organic substances, or hybrid materials of both can be used.

Examples of the metal oxide, metal oxynitride or metal nitride include metal oxides such as silicon oxide, titanium oxide, indium oxide, tin oxide, indium tin oxide (ITO) and aluminum oxide, and metal nitride such as silicon nitride. Examples thereof include metal oxynitrides such as silicon oxynitride and titanium oxynitride, and metal oxycarbide such as silicon oxide.

Further, in order to improve the brittleness of the sealing layer, it is more preferable to have a laminated structure of these inorganic layers and layers made of an organic material. The stacking order of the inorganic layer and the organic layer is not particularly limited, but it is preferable to stack the inorganic layer and the organic layer alternately a plurality of times.

The method for providing the sealing layer is not particularly limited and may be any method. For example, a vacuum vapor deposition method, a sputtering method (DC sputtering or RF sputtering), a reactive sputtering method, a molecular beam epitaxy method, a cluster ion beam method, etc. Ion plating method, plasma polymerization method, atmospheric pressure plasma polymerization method, CVD method (for example, plasma CVD method, laser CVD method, thermal CVD method, etc.), coating method, sol-gel method and the like can be used.

Of these, from the viewpoint of being able to form a dense film, as an example, a method by plasma CVD treatment at atmospheric pressure or in the vicinity of atmospheric pressure can be mentioned as a preferable example. For example, an atmospheric pressure plasma discharge processing apparatus having the configuration described in JP-A-2004-68143 can be used to form an inorganic sealing layer made of _{SiO x.}

As another example of the sealing layer, it is also preferable to form the sealing layer by the plasma CVD method using hexamethyldisiloxane (HMDSO) as a raw material, and in that case, the thin film is formed by the vacuum plasma CVD method. It is preferable to manufacture the sealing layer by using an opposed roller type roll-to-roll film forming apparatus.

FIG. 4 is a schematic view showing an example of a vacuum plasma CVD apparatus used for forming the sealing layer used in the present invention.

As shown in FIG. 4, the film forming apparatus 200 includes a feeding roller 210, transfer rollers 211 to 214, first and second film forming rollers 215 and 216, a take-up roller 217, a gas supply pipe 218, and a vacuum. It has a power source for generation 219, magnetic field generators 220 and 221, a vacuum chamber 230, a vacuum pump 240, and a control unit 241. The base material 201a on which the molecular conversion layer unwound from the delivery roller 210 is formed becomes base materials 201b to 201c by forming a gas barrier layer on the molecular conversion layer, is conveyed, and is wound by the take-up roller 217. ..

Magnetic field generators 220 and 221 are installed inside the first and second film forming rollers 215 and 216, respectively. By providing such a magnetic field generator, it is possible to promote the formation of a magnetic field in which magnetic field lines swell near the surface of each film forming roller on the opposite side, and plasma is likely to converge on the bulging portion. Efficiency can be improved.

A high frequency voltage for plasma generation is applied to the first film forming roller 215 and the second film forming roller 216 by the plasma generation power source 219. As a result, an electric field is formed in the film forming portion S between the first film forming roller 215 and the second film forming roller 216, and discharge plasma of the film forming gas supplied from the gas supply pipe 218 is generated on the base material. A gas barrier layer is formed on the surface.

A silicon compound can be used as the raw material gas. Examples of the silicon compound include hexamethyldisiloxane (HMDSO), 1,1,3,3-tetramethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, and diethylsilane. , Ppropylsilane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, dimethyldisilazane, trimethyldisilazan, tetramethyldisilazane, pentamethyldisilazane, hexamethyldisilazane, 2, Examples thereof include 4,6,8-tetramethylcyclotetrasiloxane and octamethylcyclotetrasiloxane.

As the film-forming gas, a reaction gas may be used in addition to the raw material gas. As the reaction gas, a gas that reacts with the raw material gas to form a silicon compound such as an oxide or a nitride is selected. As the reaction gas for forming an oxide as a thin film, for example, oxygen gas or ozone gas can be used. In addition, you may use these reaction gases in combination of 2 or more types.

As the film-forming gas, a carrier gas may be further used to supply the raw material gas into the vacuum chamber 230. Further, as the film forming gas, a discharge gas may be further used to generate plasma. As the carrier gas and the discharge gas, for example, a rare gas such as argon, hydrogen or nitrogen is used.

The thickness of the sealing layer is preferably in the range of 15 to 1500 nm, more preferably in the range of 20 to 1000 nm, and even more preferably in the range of 30 to 500 nm. Within this range, the advantage of achieving both productivity and gas barrier properties can be obtained. The thickness of the sealing layer can be measured by observation with a transmission electron microscope (TEM).

Further, since the protective layer according to the present invention has a feature that it can be produced by a wet forming method called an inkjet printing method, it is also preferable to adopt a wet forming method for the sealing layer from the viewpoint of simplification of the apparatus. Examples of the wet forming method include a spray coating method, a spin coating method, a blade coating method, a dip coating method, a casting method, a roll coating method, a bar coating method, a die coating method, and a printing method including an inkjet printing method. The method by patterning of is mentioned. Above all, it is preferable to form by the above-mentioned inkjet printing method.

The sealing layer produced by the wet forming method is preferably a layer obtained by applying a coating liquid containing at least polysilazane (hereinafter, may be referred to as PHPS) and modifying the dried layer.

The thickness of the gas barrier layer containing the modified polysilazane after drying is preferably in the range of 30 to 1000 nm, more preferably in the range of 50 to 800 nm, and particularly preferably in the range of 100 to 500 nm. This is preferable from the viewpoint of achieving both gas barrier properties and flexibility.

<Polysilazane>
Polysilazane is a polymer having a silicon-nitrogen bond, and is a ceramic such as _{SiO 2} , Si ₃ N ₄ , and both intermediate solid solutions SiO _x N _y having a bond of Si—N, Si—H, N—H, etc. It is a precursor inorganic polymer.

Specifically, polysilazane preferably has the partial structure of the following general formula (3).

In the above general formula (3), R ₁ , R ₂ and R ₃ are independently hydrogen atoms, substituted or unsubstituted alkyl groups, aryl groups, vinyl groups or (trialkoxysilyl) alkyl groups, respectively. .. At this time, R ₁ , R ₂ and R ₃ may be the same or different from each other. Here, examples of the alkyl group include a linear, branched chain or cyclic alkyl group having 1 to 8 carbon atoms. More specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n. -Hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group and the like. Further, examples of the aryl group include an aryl group having 6 to 30 carbon atoms. More specifically, non-condensed hydrocarbon groups such as phenyl group, biphenyl group and terphenyl group; pentarenyl group, indenyl group, naphthyl group, azulenyl group, heptalenyl group, biphenylenyl group, fluorenyl group, acenaftyrenyl group and preadenyl group. , Acenaphthenyl group, phenalenyl group, phenanthryl group, anthryl group, fluoranthenyl group, acephenanthrylenyl group, acetylenyl group, triphenylenyl group, pyrenyl group, chrysenyl group, naphthacenyl group and other condensed polycyclic hydrocarbon groups Can be mentioned. Examples of the (trialkoxysilyl) alkyl group include an alkyl group having 1 to 8 carbon atoms having a silyl group substituted with an alkoxy group having 1 to 8 carbon atoms. More specifically, a 3- (triethoxysilyl) propyl group, a 3- (trimethoxysilyl) propyl group and the like can be mentioned. The _{substituents sometimes present in R 1 to} R ₃ are not particularly limited, but for example, an alkyl group, a halogen atom, a hydroxy group (-OH), a mercapto group (-SH), a cyano group (-CN), and the like. sulfo group _(-SO 3 H), carboxyl group (-COOH), a is nitro group (-NO _2). It should be noted that the substituents present in some cases may not be the same as _{those of R 1 to} R _{3 to be substituted.} For example, when R _{1 to} R ₃ are alkyl groups, they are not further substituted with alkyl groups. Of these, preferably R ₁ , R ₂ and R ₃ are hydrogen atoms, methyl groups, ethyl groups, propyl groups, isopropyl groups, butyl groups, isobutyl groups, tert-butyl groups, phenyl groups, vinyl groups, 3 -(Triethoxysilyl) propyl group or 3- (trimethoxysilylpropyl) group.

Further, in the above general formula (3), n is an integer, and it is preferable that polysilazane having a structure represented by the general formula (3) is defined to have a number average molecular weight of 150 to 150,000 g / mol.

In the compound having the structure represented by the general formula (3), one of the preferred embodiments is perhydropolysilazane in which all of _{R 1} , R ₂ and R _{3 are hydrogen atoms.}

Polysilazane is commercially available in a solution state in which it is dissolved in an organic solvent, and the commercially available product can be used as it is as a coating liquid for forming a gas barrier layer. Commercially available products of polysilazane solution include Aquamica (registered trademark) NN120-10, NN120-20, NAX120-20, NN110, NN310, NN320, NL110A, NL120A, NL120-20, NL150A, NP110 manufactured by AZ Electronic Materials Co., Ltd. , NP140, SP140 and the like.

When polysilazane is used, the content of polysilazane in the gas barrier layer before the reforming treatment can be 100% by mass when the total mass of the gas barrier layer is 100% by mass. When the gas barrier layer contains something other than polysilazane, the content of polysilazane in the layer is preferably 10% by mass or more and 99% by mass or less, and 40% by mass or more and 95% by mass or less. It is more preferable, and particularly preferably 70% by mass or more and 95% by mass or less.

Further, as another example of polysilazane that is ceramicized at a low temperature, a silicon alkoxide-added polysilazane obtained by reacting a polysilazane having a main skeleton composed of a unit represented by the above general formula (3) with a silicon alkoxide (for example, JP-A-5-238827 (see JP-A-5-238827), Glycidol-added polysilazane obtained by reacting glycidol (see, for example, JP-A-6-122852), and alcohol-added polysilazane obtained by reacting alcohol (see, for example, JP-A-6-12852). 6-240208 (see), metal carboxylate-added polysilazane obtained by reacting metal carboxylates (see, for example, JP-A-6-299118), and acetylacetonate complexes containing metals are reacted. Examples thereof include the obtained acetylacetonate complex-added polysilazane (see, for example, JP-A-6-306329), the metal fine particle-added polysilazane obtained by adding metal fine particles (see, for example, JP-A-7-196986), and the like. Be done.

The sealing layer used in the present invention preferably contains polysilazane and a modified product thereof, and the modified product can be obtained by, for example, modifying polysilazane in the polysilazane-containing layer formed by an inkjet printing method. Be done. The reforming treatment refers to a reaction in which a part or all of polysilazane is converted into silicon oxide or silicon nitride.

As the reforming treatment, it is preferable to carry out the vacuum ultraviolet irradiation treatment by the method described in the above-mentioned publicly known documents.

[4] Electronic Device The inkjet ink of the present invention is preferably applied to an organic electronic device, and examples of the organic electronic device include an organic electroluminescence element, a photoelectric conversion element, and a solar cell.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In the examples, the indication of "parts" or "%" is used, but unless otherwise specified, it indicates "parts by mass" or "% by mass".

[Preparation of cured silicone rubber film].

<Preparation of base material>
A substrate to be used in the examples was prepared by providing a 100 nm-thick polyethylene terephthalate (PET) film (manufactured by Toray Industries, Inc., Lumirror U48) on one side by vapor deposition of an aluminum film having a thickness of 100 nm.

<Preparation of film samples 1 to 5 provided with a cured silicone rubber film (invention)>
(Preparation of film sample 1)
The first polysiloxane (a ₁ ) according to the present invention (denoted as siloxane a _{1 in the} table): 10 g of the exemplary compound (2) of the general formula (1) and the second polysiloxane (a _{2) according to the present invention.} ) (Indicated as siloxane a _{2 in the} table): 1 g of the exemplary compound (5) of the general formula (2) and 0.1 g of an n-butanol solution of chloroplatinic acid (platinum concentration 2%) as the catalyst (B). , 85 g of hexamethyldisiloxane (denoted as HMDSO) as a volatile siloxane diluent (C) and 4 g of silica fine particles having an average particle size of 20 nm as a surface tension adjuster (D) are mixed and stirred, and then put into a 5 μm filter. The ink 1 of the present invention was prepared by filtering. Using this ink 1, a discharge film is formed on the aluminum vapor deposition film surface side of the PET substrate described above with an inkjet printer (DMP-2850, manufactured by Fuji Film Co., Ltd.), air-dried at room temperature for 30 minutes, and then at 150 ° C. By heating for 10 minutes, a film sample 1 provided with a cured silicone rubber film was prepared.

The surface tension of the prepared ink was measured by the following measuring method and found to be 40 mN / m.

<Surface tension measurement method>
The surface tension of the inkjet ink was measured by the willmy method (plate method). More specifically, it is calculated by contacting the willmy plate with the liquid sample to give strain and measuring the force of pulling the willmy plate into the liquid. As the measuring device, Leosurf, which is a dynamic surface tension measuring device manufactured by UBM Co., Ltd., was used.

The surface tension is measured after the ink liquid temperature and room temperature are kept constant. Specifically, the ink was left in an environment of room temperature (20 ° C.), and the surface tension of the ink was measured when the liquid temperature of the ink reached 20 ° C.

(Preparation of film sample 2)
In the production of the film sample 1, the film sample 2 was produced in the same manner as in the production of the film sample 1 except that the silica fine particles were _{changed to titanium oxide fine particles (TiO 2).}

(Preparation of film sample 3)
In the preparation of the film sample 2, the film sample 3 was prepared in the same manner as in the preparation of the film sample 2 except that the titanium oxide fine particles were changed to 2 g and the hexamethyldisiloxane was changed to 87 g.

(Preparation of film sample 4)
In the preparation of the film sample 1, the silica fine particles were changed to tetraethylene glycol diacrylate (denoted as double-ended diacrylic), heated at 150 ° C. for 10 minutes, and then irradiated with a high-pressure mercury lamp at an amount of 0.5 J / cm ² The film sample 4 was prepared in the same manner as in the preparation of the film sample 1 except that the film sample was irradiated with ultraviolet rays.

(Preparation of film sample 5)
In the preparation of the film sample 4, the film was prepared in the same manner as in the preparation of the film sample 4 except that the tetraethylene glycol diacrylate was changed to 2 g of diethylene glycol divinyl ether (denoted as both-terminal divinyl) and the hexamethyldisiloxane was changed to 87 g. Sample 5 was prepared.

<Preparation of film samples 6 to 8 (comparison)>
(Preparation of film sample 6)
In the preparation of the film sample 1, the film sample 6 was prepared in the same manner as in the preparation of the film sample 1 except that the hexamethyldisiloxane was changed to 89 g without adding silica fine particles.

(Preparation of film sample 7)
In the preparation of the film sample 1, the film sample 7 was prepared in the same manner as in the preparation of the film sample 1 except that hexamethyldisiloxane and silica fine particles were not added.

(Preparation of film sample 8)
Aluminum vapor deposition of the PET substrate described above using an ink prepared by mixing and stirring 10 g of tricyclodecanedimethanol diacrylate, 0.2 g of IRGACURE184 (manufactured by BASF Japan Ltd.), and 90 g of propylene glycol monomethyl ether. An ejection film is formed on the film surface side with an inkjet printer, dried at 80 ° C. for 10 minutes, and then irradiated with ultraviolet rays with ^{an irradiation energy amount of 0.5 J / cm 2 using a high-pressure mercury lamp to form an acrylic resin film.} The provided film sample 8 was prepared.

≪Evaluation≫
[Inkjet ejection performance evaluation]
With respect to the inkjet ink used for producing each of the film samples 1 to 8, the inkjet ejection property of the inkjet printer was evaluated according to the following criteria.
〇: Nozzle clogging and no ink adhesion to the nozzle plate, stable ejection is possible. Δ: Ink adhesion to the nozzle plate is observed and unstable ejection is observed. ×: Nozzle clogging prevents ejection. In the film sample 7, since the volatile siloxane diluent (C) was not added, the viscosity increased and the ink could not be ejected.

[Evaluation of inkjet coating properties]
The inkjet coating properties of each film sample 1 to 8 were evaluated according to the following criteria.

〇: A solid film with a uniform film thickness can be formed in the entire coating film area. Δ: A region with a non-uniform film thickness is partially formed. Can not

[Adhesion evaluation].
The adhesion of each film sample 1 to 8 to the substrate was evaluated according to the following criteria. Adhesion evaluation was performed according to the following procedure.

1) Fix the evaluation film on the workbench with tape 2) After making a notch in a part of the film, firmly attach cellophane tape (registered trademark) so as to include the notch. At that time, do not completely attach the tape on the front side to the base material, but hold it by hand. 3) Hold the end of the tape on the front side that has not been attached and quickly peel it off to the back of the upper surface. Δ: Peeling starting from a partial notch is seen ×: All tape adhesive parts are peeled off

[Preparation of gas barrier film]
<Formation of upper gas barrier layer>

Gas barrier film samples 1-1 to 1-8 were prepared by further providing a gas barrier layer made of a CVD film on the upper layers of each film sample 1 to 8.

(Formation of CVD film)

A gas barrier layer (100 nm) made of an inorganic film was formed by a plasma CVD method under the following conditions.

Raw material gas (gas flow rate): Silane gas (100 sccm), ammonia gas (200 sccm), nitrogen gas (500 sccm), hydrogen gas (500 sccm)
Pressure: 50Pa
Frequency: 13.5MHz
Electric power: 3000W
Chamber temperature: 100 ° C
[Gas barrier property evaluation]

The gas barrier property was evaluated for each gas barrier film sample 1-1 to 1-8. Evaluation of gas barrier properties is used manufactured by MOCON AQUATRAN, 38 ° C., numeric in 100% RH conditions by measuring the water vapor permeability waiting to stabilize ^{(g / (m 2 · day} )), the following Evaluated by criteria.

^{〇: 1 × 10 -2 (g /} (m 2 · day)) less ^{△: 1 × 10 -2 (g} / (m 2 · day)) or ^{more, 1 × 10 -1 (g /} (m 2 · day )) Less than ×: 1 × 10 ^-1 (g / (m ² · day)) or more The composition of the film sample and the above evaluation results are shown in Tables I and II.

_{From the results of Tables I and II, the first polysiloxane (a 1} ) having two or more alkenyl groups in the molecule as a liquid silicone rubber (A) having a unit structure represented by the general formula (A). _{, A second polysiloxane (a 2} ) having two or more hydrosilyl groups in the molecule, a platinum-based hydrosilylation catalyst (B), a volatile siloxane diluent (C), and the surface of the liquid before addition. It was found that the ink for inkjet of the present invention to which the material shown in Table I was added as a surface tension adjusting agent (D) capable of increasing the tension was excellent in IJ ejection property, IJ coating property and adhesion. ..

Further, it was found that the gas barrier film formed by using the inkjet ink of the present invention is also excellent in gas barrier property.

The inkjet ink of the present invention can be directly applied when forming a protective layer containing silicone rubber on an organic electronic device by inkjet printing, and there is no damage to the organic electronic device, and further on the protective layer. Since a high gas barrier property can be obtained even if a sealing layer is directly provided on the surface, it is suitable for producing a gas barrier film and for an organic electroluminescence element, a photoelectric conversion element, a solar cell, etc. provided with the gas barrier film.

1 Organic electronic device 2 Protective layer 3 Smooth layer 4 Sealing layer F substrate, flexible substrate, electronic device EL ink coating 30 Inkjet head 31, 39 Pump 32 Filter 33 Piping branch 34 Waste liquid tank 35 Control unit 36, 37, 38A , 38B Tank 50 Inkjet head 56 Housing 57 Cap receiving plate 59 Cover member 61 Nozzle plate 62 Cap receiving plate mounting part 68 Mounting hole 71 Nozzle opening 81a 1st joint 81b 2nd joint 82 3rd joint 200 Film deposition equipment 201a, b, c Base material 210 Feeding roller 211, 212, 213, 214 Conveying roller 215 First film forming roller 216 Second film forming roller 217 Winding roller 218 Gas supply pipe 219 Plasma generation power supply 220, 221 Magnetic field generator 230 Vacuum chamber 240 Vacuum pump 241 Control unit

Claims (13)

Inkjet ink containing liquid silicone rubber
It contains at least a liquid silicone rubber (A) having a unit structure represented by the general formula (A), a catalyst (B), a volatile siloxane diluent (C), and a surface tension adjusting agent (D). Ink for inkjet characterized by that.

(In the formula, R represents an unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bond having 1 to 8 carbon atoms. R'represents a substituent synonymous with R, and R R'may be the same or different. N represents an integer greater than or equal to 1.) The liquid silicone rubber (A) has a _{first polysiloxane (a 1) having two or more alkenyl groups in the molecule and a second} polysiloxane (a 2) having two or more hydrosilyl groups in the molecule. ), The ink for inkjet according to claim 1, wherein the catalyst (B) is a hydrosilylation catalyst. The inkjet ink according to claim 1 or 2, wherein the surface tension at 20 ° C. after the addition of the surface tension adjusting agent (D) is within the range of 20 to 35 mN / m. The inkjet ink according to any one of claims 1 to 3, wherein the volatile siloxane diluent (C) contains a low-molecular-weight siloxane compound. The ink jet ink according to any one of claims 1 to 4, wherein the surface tension adjusting agent (D) is a photocurable polyfunctional monomer. The inkjet ink according to any one of claims 1 to 5, wherein the surface tension adjusting agent (D) is a metal oxide fine particle. The ink jet ink according to claim 6, wherein the metal oxide fine particles are silicon oxide particles or titanium oxide particles. A film forming method comprising a step of forming an ink coating film on a substrate by using the inkjet ink according to any one of claims 1 to 7. 8. Claim 8 is characterized by having a step of drying the ink coating film to remove a volatile siloxane diluent, and then a step of forming a cured silicone rubber film by irradiating the ink coating film with ultraviolet rays. The film forming method according to. The film forming method according to claim 8 or 9, further comprising a step of forming a multifunctional film by directly ejecting the inkjet ink onto an organic electronic device. An ink coating film formed by using the inkjet ink according to any one of claims 1 to 7. A cured silicone rubber film formed by using the inkjet ink according to any one of claims 1 to 7. A multifunctional film formed by using the inkjet ink according to any one of claims 1 to 7.

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