Inkjet printing ink, ink preparation method, insulating material and equipment

Abstract

The invention discloses ink-jet printing ink which is prepared from the following components in parts by weight: 20 to 40 parts of DOPO structure modified epoxy acrylate, 40 to 60 parts of active monomer, 5 to 10 parts of initiator, 0.5 to 5 parts of pigment and 1 to 3 parts of additive. According to the ink disclosed by the invention, the DOPO structure modified epoxy acrylate is taken as matrix resin, and the resin can form stable bonding force on the surface of a base material in a UV light curing reaction process, so that the cured ink has relatively high firmness on a metal surface, and a formed insulating coating has relatively good adhesive force and high-temperature and high-humidity resistance; in addition, the DOPO structure modified epoxy acrylate can also properly adjust the surface tension of the liquid ink, so that the ink forms homogeneous ink droplets in the ink jet printing process, ink misting is prevented, and accurate ink jet printing is further achieved. In addition, the invention also discloses a preparation method of the ink, an insulating material and equipment.

Description

Technical Field

[0001] The invention relates to the field of polymer insulating materials, and in particular to an inkjet printing ink, a method for preparing the ink, an insulating material and equipment. Background Art

[0002] In order to insulate the equipment, the surfaces of metal parts such as power battery housings and display devices need to be coated or laminated with insulating materials. Traditional processes mostly use the method of laminating blue insulating protective film or spraying insulating paint. However, the process of laminating blue insulating protective film on power battery housings and other equipment is relatively complicated, requiring coating, die-cutting, laminating and other processes, and there is a problem of low film size accuracy and easy rework; when spraying insulating paint for insulation protection, a large amount of solvent is needed to dilute the insulating paint before spraying, which will cause a large amount of VOC emissions, and the sprayed insulating paint needs to be cured at high temperature, with low material utilization and safety.

[0003] Therefore, it is necessary to provide a UV curing insulating ink with good adhesion suitable for inkjet printing. Summary of the invention

[0004] The main purpose of the present invention is to provide an inkjet printing ink, aiming to solve the problem that the existing insulating ink cannot be accurately printed.

[0005] To achieve the above object, the present invention provides an inkjet printing ink, which includes: by weight, the ink includes 20-40 parts of DOPO structure-modified epoxy acrylate, 40-60 parts of active monomers and 5-10 parts of initiators.

[0006] The inkjet printing ink provided by the present invention has a viscosity and surface tension suitable for printing, can achieve precise printing, and has a high ink utilization rate; the insulating coating obtained by printing the ink of the present invention meets the insulation requirements, has good adhesion to the substrate, is voltage-resistant and friction-resistant, and has stable performance in a high temperature and high humidity environment.

[0007] The present invention further provides a method for preparing an inkjet printing ink, the method comprising the following steps:

[0008] The DOPO structure-modified epoxy acrylate and the active monomer are mixed, and then an initiator, an auxiliary agent and a pigment are added to the obtained mixture, and the mixture is stirred evenly to obtain a liquid ink;

[0009] The liquid ink is ground and filtered to obtain the inkjet printing ink.

[0010] The present invention further provides an insulating material, which comprises a substrate and an insulating coating covering at least a portion of the surface of the substrate, wherein the insulating coating is formed by spraying the inkjet printing ink described in the present invention.

[0011] The insulating coating formed on the substrate is accurately positioned, has high adhesion to the substrate, and is resistant to high temperature and high humidity.

[0012] The present invention further provides a device comprising the insulating material of the present invention.

[0013] The beneficial effects of the technical solution of the present invention are:

[0014] (1) The ink provided by the present invention uses DOPO structure-modified epoxy acrylate as the main resin, which can form a stable bonding force on the surface of the substrate during the UV light curing reaction, so that the cured ink has a high firmness on the metal surface and good adhesion on the substrate;

[0015] (2) The ink has a viscosity suitable for inkjet printing, and the DOPO structure-modified epoxy acrylate can also properly adjust the surface tension of the liquid ink so that the ink forms homogeneous ink droplets during the inkjet printing process, thereby preventing ink from flying and achieving accurate inkjet printing;

[0016] (3) The insulating coating obtained by printing with the ink of the present invention meets the insulation requirements, is voltage-resistant and friction-resistant, and has stable performance under high temperature and high humidity environments. DETAILED DESCRIPTION

[0017] The scheme in the embodiment of the present invention will be described clearly and completely below. Obviously, the described embodiment is only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0019] The invention provides an inkjet printing ink, which comprises, by weight, 20-40 parts of DOPO structure-modified epoxy acrylate, 40-60 parts of active monomers, 5-10 parts of initiators, 0.5-5 parts of pigments and 1-3 parts of auxiliary agents.

[0020] The technical solution of the present invention adopts DOPO structure-modified epoxy acrylate and active monomers to make the ink have a viscosity suitable for printing, can achieve precise printing, and has high ink utilization rate; the ink can completely solidify the ink layer within 0.1-1s, and the insulating coating obtained by printing with the ink of the present invention meets the insulation requirements, has good adhesion to the substrate, is voltage-resistant and friction-resistant, and has stable performance in high temperature and high humidity environments.

[0021] The ink provided by the present invention uses DOPO structure-modified epoxy acrylate as the main resin. After the DOPO structural group is introduced into the epoxy acrylate structure, it has high affinity with the substrate interface and can form a stable bonding force on the substrate surface during the UV light curing reaction, so that the cured ink has a high firmness on the metal surface, and the formed insulating coating has better adhesion, friction resistance and high temperature and humidity resistance. The DOPO structure-modified epoxy acrylate can also appropriately adjust the surface tension of the liquid ink so that the ink forms homogeneous ink droplets during the ink printing process to prevent ink flying, thereby achieving precise ink printing.

[0022] In addition, the DOPO structure-modified epoxy acrylate also has a certain flame retardant effect, and can significantly improve the flame retardancy of the ink after curing.

[0023] In some embodiments of the present invention, the viscosity of the ink at 25° C. is 10-30 mpa·s, and the surface tension is 25-32 mN / m. In this way, precise ink printing can be achieved, and the coating formed by the ink has better adhesion.

[0024] In the present invention, the DOPO structure-modified epoxy acrylate is a DOPO structure-modified bisphenol A type epoxy acrylate. Specifically, the DOPO-modified epoxy acrylate is prepared by reacting bisphenol A type epoxy resin, a DOPO structure-containing compound and acrylic acid. The bisphenol A type epoxy resin is preferably E44 epoxy resin.

[0025] In some embodiments of the present invention, the DOPO structure-modified epoxy acrylate is prepared by the following method:

[0026] S1, adding bisphenol A epoxy resin, DOPO or its derivatives, a catalyst and a polymerization inhibitor into a reactor and mixing them to obtain a first mixture;

[0027] S2, heating the first mixture to a first temperature, and adding acrylic acid to the first mixture at the first temperature to obtain a second mixture;

[0028] S3. Raising the temperature of the second mixture to a second temperature under stirring to react and obtain the modified epoxy acrylate.

[0029] In some embodiments of the present invention, the mass ratio of the bisphenol A epoxy resin, acrylic acid and DOPO or its derivatives can be 100:(15-30):(30-60), and epoxy acrylate with DOPO is obtained. Among them, the molecular structure of DOPO or its derivatives contains PH bonds, which can react with olefins, epoxy bonds or carbonyl groups. At the same time, since DOPO or its derivatives contain cyclic O=PO bonds, the ink compounded with active monomers in the present invention has higher dielectric strength; in addition, since the DOPO structure contains a cyclic organic phosphorus structure, it can play a flame retardant role.

[0030] In the present invention, when DOPO or its derivatives are used to modify the epoxy acrylic resin, when the DOPO dosage is too low, the adhesion and flame retardancy of the ink after curing are poor, and when the DOPO structural group content in the modified epoxy acrylic resin is too high, the viscosity of the ink is too high and cannot meet the requirements of inkjet printing.

[0031] In some embodiments of the present invention, the mass ratio of the bisphenol A epoxy resin to the catalyst may be 100:0.2-0.8.

[0032] In some embodiments of the present invention, the mass ratio of the polymerization inhibitor to the acrylic acid may be 0.1-0.3:100;

[0033] Wherein, the catalyst may be one or more selected from triethylamine, triethanolamine and triphenylphosphine; the inhibitor may be one or more selected from o-methylhydroquinone, p-hydroxyanisole and p-benzoquinone.

[0034] In some embodiments of the present invention, in step S1, the first temperature is 100-120°C.

[0035] In some embodiments of the present invention, in step S2, the second temperature is 120-140° C. and the reaction time is 2-4 h.

[0036] In some embodiments of the present invention, the active monomer can be selected from one or more of isobornyl methacrylate, isobornyl acrylate, pentaerythritol tetraacrylate, ethoxyethoxyethyl acrylate, 1,6-hexanediol diacrylate, dipropylene glycol diacrylate, ethoxylated trimethylolpropane triacrylate, hydroxyethyl acrylate, 2-ethylacryloyloxymethyl phosphate, and hydroxyethyl acrylate phosphate. In this way, the active monomer can have good compatibility with DOPO structure-modified epoxy acrylate, balance the viscosity and surface tension of the ink, and provide excellent physical and chemical properties of the ink after curing, such as making the insulating coating have better adhesion and high temperature and humidity resistance.

[0037] In some embodiments of the present invention, the initiator is selected from one or more of alkyl phenone photoinitiators, acylphosphine oxide photoinitiators and anthrone photoinitiators.

[0038] In some preferred embodiments of the present invention, the initiator can be selected from one or more of 2,4,6-trimethylbenzoyl-di(p-tolyl)phosphine oxide (TMO), 2-hydroxy-2-methyl-1-phenyl-1-propanone (trade name 1173), 1-hydroxy-cyclohexyl-phenyl ketone (trade name 184), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TPO), 2-isopropylthioxanthone (ITX), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (trade name 819) and 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone (trade name 907).

[0039] In the present invention, when the amount of active monomer in the ink is too low, the viscosity of the ink is too high and cannot meet the printable viscosity requirement. When the amount of active monomer is too high, the adhesion and flame retardancy of the ink layer after the ink is cured cannot meet the requirements.

[0040] In some preferred embodiments of the present invention, the ink comprises, by weight, 20-40 parts of DOPO structure-modified epoxy acrylate, 45-55 parts of active monomer, 5-8 parts of initiator, 1-2 parts of auxiliary agent and 1-3 parts of pigment.

[0041] In some embodiments of the present invention, the pigment may be an organic pigment or an inorganic pigment. Specifically, the pigment may be selected from one or more of phthalocyanine blue, phthalocyanine green, titanium black and titanium dioxide.

[0042] The auxiliary agent is selected from one or more of a defoamer, a silane coupling agent and a leveling agent to reduce or eliminate the foam in the ink, so that the ink meets the printing requirements and has good leveling properties to increase the adhesion of the ink layer after curing.

[0043] Wherein, the coupling agent may be one or more of the silane coupling agents KH550, KH560, KH570 and KH792.

[0044] The present invention further proposes a method for preparing the above-mentioned inkjet printing ink, which comprises the following steps: mixing modified epoxy acrylate and active monomer, then adding initiator, auxiliary agent and pigment to the obtained mixture, stirring evenly to obtain liquid ink; grinding and filtering the liquid ink to obtain the inkjet printing ink.

[0045] In some specific embodiments of the present invention, the preparation method of the inkjet printing ink comprises the following steps: weighing 20-40 parts by weight of modified epoxy acrylate, 40-60 parts by weight of active monomer, 5-10 parts by weight of initiator and 1-5 parts by weight of auxiliary agent, mixing the modified epoxy acrylate and the active monomer, and then adding the initiator, pigment and auxiliary agent to the obtained mixture, stirring evenly at 400-600 rpm to obtain a uniform liquid ink; grinding the liquid ink until the pigment particles in the ink are below 0.6 μm and the viscosity is 10-30 mpa·s, filtering with a 0.6 μm filter screen or filter element to obtain the inkjet printing ink.

[0046] The present invention further proposes an insulating material, comprising a substrate and an insulating coating covering at least a portion of the surface of the substrate, wherein the insulating coating is formed by printing any of the inkjet printing inks. The insulating coating formed on the substrate is accurately positioned, has high adhesion to the substrate, is resistant to abrasion, and is resistant to high temperature and humidity. The substrate may be metal.

[0047] The present invention further provides a device, comprising the above-mentioned insulating material, wherein the device may be a power battery or a display device.

[0048] The present invention is described below in conjunction with specific embodiments, but the present invention is not limited to the conditions of the following embodiments.

[0049] The materials used in the examples of the present invention and comparative example 1 are all commercially available, wherein epoxy resin E44 is purchased from Sanmu Group;

[0050] 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0051] The leveling agent was KMT7015 and the defoaming agent was KMT2030, which were purchased from Foshan Koning New Materials Co., Ltd.

[0052] Example 1

[0053] This embodiment is used to illustrate the preparation method of the inkjet printing ink provided by the present invention, and the method comprises:

[0054] (1) Preparation of modified acrylic epoxy resin

[0055] S1, adding epoxy resin E44, DOPO, catalyst triethylamine and inhibitor o-methyl hydroquinone into a reactor and mixing them to obtain a first mixture; wherein the mass ratio of epoxy resin E44, DOPO, triethylamine and o-methyl hydroquinone is 100:50:0.5:0.02;

[0056] S2, heating the first mixture to 110° C., adding acrylic acid to the first mixture to obtain a second mixture; wherein the mass ratio of epoxy resin E44 to acrylic acid is 100:20;

[0057] S3. Raising the temperature of the second mixture to 130° C. and keeping the temperature for 3 hours under stirring to obtain the modified epoxy acrylate.

[0058] (2) Preparation of inkjet printing ink

[0059] Weigh 30 parts by weight of modified epoxy acrylate, 50 parts by weight of isobornyl methacrylate, 7 parts by weight of initiator TPO, 0.3 parts by weight of leveling agent, 0.2 parts by weight of defoamer and 0.5 parts by weight of coupling agent KH550;

[0060] The modified epoxy acrylate and isobornyl methacrylate were mixed, and then TPO, pigment phthalocyanine blue, leveling agent, defoaming agent and coupling agent were added to the obtained mixture, and the mixture was stirred evenly at 500 rpm to obtain a uniform liquid ink; the liquid ink was ground and filtered using a 0.6 μm filter screen or filter element to obtain the inkjet printing ink, which was recorded as P1, and the properties are shown in Table 1.

[0061] Example 2

[0062] The method for preparing the inkjet printing ink in this embodiment is carried out in accordance with the method of embodiment 1, and the difference from embodiment 1 is that the amount of the active monomer isobornyl methacrylate is 40 parts by weight. The inkjet printing ink obtained is denoted as P2, and the properties are shown in Table 1.

[0063] Example 3

[0064] The method for preparing the inkjet printing ink in this embodiment is carried out in accordance with the method of embodiment 1, and the difference from embodiment 1 is that the amount of the active monomer isobornyl methacrylate is 60 parts by weight. The inkjet printing ink obtained is denoted as P3, and the properties are shown in Table 1.

[0065] Example 4

[0066] The method for preparing inkjet printing ink in this embodiment is carried out in accordance with the method of embodiment 1, and the difference from embodiment 1 is that the active monomers are ethoxyethoxyethyl acrylate and 1,6-hexanediol diacrylate in equal parts by weight. The obtained inkjet printing ink is denoted as P4, and the properties are shown in Table 1.

[0067] Example 5

[0068] The method for preparing inkjet printing ink in this embodiment is carried out with reference to Example 1, and the difference between this embodiment and Example 1 is that:

[0069] In step (1), the mass ratio of epoxy resin E44, DOPO, triethylamine and o-methyl hydroquinone is 100:30:0.5:0.02. The obtained inkjet printing ink is denoted as P5, and the properties are shown in Table 1.

[0070] Comparative Example 1

[0071] The method for preparing the ink in this comparative example is carried out with reference to Example 1, and the difference between the method and Example 1 is that: in step (1), DOPO is not added to modify the epoxy resin;

[0072] The mass ratio of epoxy resin E44, ethylamine and o-methyl hydroquinone is 100:0.5:0.02. The obtained inkjet printing ink is denoted as D1, and the properties are shown in Table 1.

[0073] Comparative Example 2

[0074] The method for preparing the ink in this comparative example is carried out in accordance with Example 1, and the difference from Example 1 is that the amount of the active monomer isobornyl methacrylate is 30 parts by weight. The obtained inkjet printing ink is denoted as D2, and the properties are shown in Table 1.

[0075] Comparative Example 3

[0076] The method for preparing the ink in this comparative example is carried out in accordance with Example 1, and the difference from Example 1 is that the amount of the active monomer isobornyl methacrylate is 70 parts by weight. The inkjet printing ink obtained is denoted as D3, and the properties are shown in Table 1.

[0077] Table 1

[0078]

[0079] From the data in the above table, it can be found that the ink provided by the present invention has a viscosity and surface tension suitable for inkjet printing, and is conducive to realizing intelligent and precise printing, thereby achieving high ink utilization.

[0080] Performance Testing

[0081] The inkjet printing ink prepared in Examples 1-5 and Comparative Examples 1-3 was loaded into an IJP high-precision printing device, and the text or pattern that needed ink protection was designed by computer and imported into the operating system. The ink was sprayed on the surface of the aluminum alloy substrate to form a 60 μm insulating coating on the substrate. UV light curing was performed simultaneously, and curing was completed within 0.1-1 s. The curing lamp used was a 395 nm LED curing lamp, and the curing energy was 800-1600 mJ / cm 2 ; Obtain insulating materials, denoted as C1-C8, and perform the following tests on C1-C8:

[0082] (1) Adhesion test

[0083] The adhesion of sample materials C1-C8 was tested. The adhesion test method was based on the "Scratch test for paint, varnish and paint film (GB / T9286-1998)". The adhesion of the insulating coating was recorded. The results are shown in Table 2.

[0084] Judging criteria:

[0085] Level 0: The cutting edge is completely smooth and there is no shedding;

[0086] Level 1: A small amount of coating falls off at the intersection of the cuts, but the falling area does not exceed 5%;

[0087] Level 2: Coating peels off at the intersection of the cuts and / or along the cuts, with the peeling area exceeding 5% but not exceeding 15%.

[0088] (2) Wear resistance test

[0089] Test method: Refer to ASTM F 2357-04 RCA paper tape abrasion test, use a special rubber for friction resistance, load a 300g weight, wipe back and forth on the sample surface for 100 cycles at a speed of 40-60 times / minute and a stroke of about 20mm.

[0090] Judgment criteria: After the test, the paint is not transparent (exposing the base material) and does not change color, and the text and pattern are not unclear or the font is not damaged.

[0091] (3) High temperature and high humidity resistance test

[0092] Test method: Under the environment of temperature 65°C and humidity 90RH%, refer to GB / T 1966-1995, conduct high temperature and high humidity test on substrates C1-C8 with insulating coating on the surface, and record the time when the insulating coating wrinkles and falls off; the results are shown in Table 2.

[0093] (4) Acid and alkali resistance test

[0094] Test method: Referring to GB / T 1966-1995, the insulating materials C1-C8 were immersed in 5wt% HCl solution and 5wt% NaOH solution for 2h respectively. The samples C1-C8 were qualified when no deformation, shrinkage, bulging and cracking occurred at the end of the test. The results are shown in Table 2.

[0095] Table 2

[0096]

[0097] (5) Dielectric strength test

[0098] The dielectric strength test of the insulating materials C1-C8 was carried out, wherein the dielectric strength test was carried out according to ASTM D149, and the volume resistivity and surface resistivity were carried out according to ASTM D257. The results are shown in Table 3.

[0099] (6) Flame retardant test

[0100] Referring to the horizontal and vertical methods for the determination of combustion performance of plastics in GB / T2408, the ink was coated on tin-plated iron or aluminum alloy with an ink layer thickness of 50-120um. After UV curing, a flame retardant test was performed and the flame retardant reached V0 level. The results are shown in Table 3.

[0101] (7) Hardness test

[0102] The paint film hardness was determined by the pencil method according to GB / T 6739-2006 for paints and varnishes. The results are shown in Table 3.

[0103] Table 3

[0104]

[0105] From the data in Table 2 and Table 3, it can be found that the insulating coating formed by inkjet printing provided by the present invention has good adhesion on the substrate, and the obtained insulating material meets the insulation requirements, withstands voltage, and has excellent wear resistance and high temperature and humidity resistance.

[0106] The above description is only a partial or preferred embodiment of the present invention, and the scope of protection of the present invention cannot be limited therefrom. All equivalent structural changes made using the contents of the present invention specification under the concept of an overall concept of the present invention, or direct / indirect application in other related technical fields are included in the scope of protection of the present invention.

Claims

1. An inkjet printing ink, characterized in that: In parts by weight, the ink comprises 20-40 parts of DOPO structure-modified epoxy acrylate, 40-60 parts of active monomer, 5-10 parts of initiator, 0.5-5 parts of pigment and 1-3 parts of auxiliary agent.

2. The inkjet printing ink according to claim 1, characterized in that The ink has a viscosity of 10-30 mpa·s at 25° C. and a surface tension of 25-32 mN / m.

3. The inkjet printing ink according to claim 2, characterized in that The DOPO structure-modified epoxy acrylate is prepared by the following method: S1, adding bisphenol A epoxy resin, DOPO or its derivatives, a catalyst and a polymerization inhibitor into a reactor and mixing them to obtain a first mixture; S2, heating the first mixture to a first temperature, and adding acrylic acid to the first mixture at the first temperature to obtain a second mixture; S3. Raising the temperature of the second mixture to a second temperature under stirring to react and obtain the modified epoxy acrylate.

4. The inkjet printing ink according to any one of claims 1 to 3, characterized in that The mass ratio of the bisphenol A epoxy resin, acrylic acid and the DOPO or its derivative is 100:(15-30):(30-60); and / or The mass ratio of the bisphenol A epoxy resin to the catalyst is 100:0.2-0.8; and / or The mass ratio of the polymerization inhibitor to the acrylic acid is 0.1-0.3:

100.

5. The inkjet printing ink according to claim 1, characterized in that In step S2, the first temperature is 100-120°C; and / or In step S3, the second temperature is 120-140°C; and the reaction time is 2-4h.

6. The inkjet printing ink according to claim 1, characterized in that The active monomer is selected from one or more of isobornyl methacrylate, isobornyl acrylate, pentaerythritol tetraacrylate, ethoxyethoxyethyl acrylate, 1,6-hexanediol diacrylate, dipropylene glycol diacrylate, ethoxylated trimethylolpropane triacrylate, hydroxyethyl acrylate, 2-ethylacryloyloxymethyl phosphate, and hydroxyethyl acrylate phosphate; and / or The initiator is selected from one or more of alkyl phenone photoinitiators, acylphosphine oxide photoinitiators and anthrone photoinitiators; and / or The auxiliary agent is selected from one or more of a defoamer, a silane coupling agent and a leveling agent; and / or The pigment is selected from one or more of phthalocyanine blue, phthalocyanine green, titanium black and titanium dioxide.

7. The inkjet printing ink according to claim 1, characterized in that In parts by weight, the ink comprises 20-40 parts of DOPO structure-modified epoxy acrylate, 45-55 parts of active monomer, 5-8 parts of initiator, 1-2 parts of auxiliary agent and 1-3 parts of pigment.

8. A method for preparing the inkjet printing ink according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: The DOPO structure-modified epoxy acrylate and the active monomer are mixed, and then an initiator, an auxiliary agent and a pigment are added to the obtained mixture, and the mixture is stirred evenly to obtain a liquid ink; The liquid ink is ground and filtered to obtain the inkjet printing ink.

9. An insulating material, characterized in that: The material comprises a substrate and an insulating coating covering at least a portion of the surface of the substrate, wherein the insulating coating is formed by printing the inkjet printing ink according to any one of claims 1 to 7.

10. A device, characterized in that: Comprising the insulating material as claimed in claim 9.

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