High-shading insulating matte black ink and preparation method thereof

Abstract

The invention discloses high-shading insulating matte black ink and a preparation method thereof, and the high-shading insulating matte black ink comprises the following components in percentage by mass: 8-10% of carbon black, 15-25% of polyester resin, 0-3% of matte powder, 1-3% of filler, 1-5% of assistant, 3-5% of blocked isocyanate curing agent, 1-3% of acrylonitrile thermal expansion microsphere, 15-30% of butanone, 5-15% of n-propyl acetate and 10-20% of ethyl acetate. Wherein the acrylonitrile thermal expansion microspheres comprise microspheres with particle sizes of 10 microns and 30 microns; the ratio of the acrylonitrile thermal expansion microspheres with the particle size of 10 microns to the acrylonitrile thermal expansion microspheres with the particle size of 30 microns is (1.1-1.3): (1.7-1.9). According to the high-shading insulating matte black ink and the preparation method thereof provided by the invention, the thermal expansion microspheres with two different particle sizes are used, the two thermal expansion microspheres with different particle sizes generate non-uniform rough surfaces after expansion, the matte effect is excellent, and meanwhile, a large number of cavities are formed in an ink film layer to store air, so that the matte effect is excellent. The insulating property of the ink layer is improved, the material ratio of polyester resin can be increased, and the adhesive force is improved.

Description

Technical Field

[0001] The present invention belongs to the field of ink preparation, and particularly relates to a high-shielding insulating matte black ink and a preparation method thereof. Background Art

[0002] High-shielding insulating matte black ink generally refers to black ink that can achieve a light transmittance of <5% on a transparent substrate (generally a PET film or a PI film) after printing, a resistance value of >1012 Ω, a glossiness of <1 (tested at a 60-degree angle with a glossiness meter), and excellent adhesion (>99%). Traditionally, in order to prepare ink meeting the aforementioned requirements, a large amount of matte powder (silica) and fillers (calcium carbonate, barium sulfate, etc.) are used to achieve the matte effect, and at the same time, a large amount of carbon black is added to meet the requirement of high shielding.

[0003] The defects of the current technology are as follows: In order to achieve a matte effect with a glossiness of <1, the black ink formulation will add too much matte powder and filler, generally 5 - 10%; in order to achieve a light transmittance of <5%, the black ink formulation will add too much carbon black, generally 10 - 15%. This results in a relatively reduced proportion of the resin (polyester resin) that provides basic adhesion in the ink formulation, so that the resin in the ink cannot completely coat the carbon black, matte powder, and filler, resulting in poor adhesion fastness after ink printing because it is the resin that has adhesion to the substrate. To solve this problem, the existing technology generally adds a curing agent containing an isocyanate group such as HDI to carry out a cross-linking curing reaction after ink printing to increase the adhesion to the substrate. However, this method will cause the ink to gradually react and cure in the ink tank during printing, and the remaining ink after printing cannot be used, and the improvement of adhesion is not very ideal. At the same time, substances such as carbon black, matte powder, and filler are not strictly high-insulating substances, and after adding a large amount of these substances to the ink, its resistance value will inevitably decrease and cannot meet the requirement of high insulation. Summary of the Invention

[0004] To solve the deficiencies of the existing technology, the present invention provides a high-shielding insulating matte black ink and a preparation method thereof.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A high-shielding insulating matte black ink, by mass percentage, comprises the following components: 8 - 10% carbon black, 15 - 25% polyester resin, 0 - 3% matte powder, 1 - 3% filler, 1 - 5% additive, 3 - 5% blocked isocyanate curing agent, 1 - 3% acrylonitrile thermally expandable microspheres, 15 - 30% methyl ethyl ketone, 5 - 15% n-propyl acetate, 10 - 20% ethyl acetate, wherein the acrylonitrile thermally expandable microspheres include microspheres with particle sizes of 10 microns and 30 microns.

[0007] Further, the filler is one or a combination of nano calcium carbonate and barium sulfate.

[0008] Further, the auxiliary agent is a mixture of one or more of a dispersant and an organosilicon leveling agent.

[0009] Further, the ratio of the acrylonitrile thermally expandable microspheres with a particle size of 10 microns to the acrylonitrile thermally expandable microspheres with a particle size of 30 microns is 1.1 - 1.3:1.7 - 1.9.

[0010] A preparation method of a high-shielding insulating matte black ink includes the following steps:

[0011] Step 1: Mix methyl ethyl ketone, n-propyl acetate and ethyl acetate evenly to obtain a mixed solvent;

[0012] Step 2: Add carbon black, filler, auxiliary agents such as a dispersant, etc. to the mixed solvent while dispersing, and disperse at a high speed at a rotation speed of 1200 - 1500 revolutions per minute for 30 - 40 minutes to obtain a mixed material;

[0013] Step 3: Grind the mixed material through a sand mill until the fineness of the ink is less than 20 microns;

[0014] Step 4: Add matte powder, thermally expandable microspheres and blocked isocyanate curing agent while dispersing, and then disperse at a high speed at a rotation speed of 1200 - 1500 revolutions per minute for 15 - 20 minutes to fully mix the materials, and filter to obtain a high-shielding insulating matte black ink.

[0015] Further, the ratio of the acrylonitrile thermally expandable microspheres with a particle size of 10 microns to the acrylonitrile thermally expandable microspheres with a particle size of 30 microns is 1.2:1.8.

[0016] A high-shielding insulating matte black ink and a preparation method thereof disclosed by the present invention, compared with the prior art, have the following beneficial effects:

[0017] 1. Using thermally expandable microspheres to replace or partially replace matte powder and filler, increasing the resin powder ratio of the black ink formula and improving the adhesion. The reduction of matte powder and filler also enables the corresponding light shielding rate to be achieved without adding a lot of carbon black;

[0018] 2. The thermally expandable microspheres use two kinds of microspheres with different particle sizes (10 microns and 30 microns). The two different particle-sized thermally expandable microspheres produce an uneven rough surface after expansion, and the resulting matte effect is better than that of using a single particle size. At the same time, a large number of voids are formed in the ink film layer to store air, improving the insulation of the ink layer;

[0019] 3. Using a blocked isocyanate group curing agent enables the ink resin and the isocyanate active groups to react only when the ink passes through the high temperature of the drying oven after printing, which can effectively reduce the reaction of the ink in the ink trough of the printing press, allowing the remaining ink in the ink trough to be saved for use in the next printing, thereby reducing the ink loss in the printing factory. Detailed implementation manner

[0020] The present invention discloses a high-shielding insulating matte black ink and a preparation method thereof. The following describes the specific implementation manner of the present invention in combination with preferred embodiments.

[0021] Preferred embodiment.

[0022] This embodiment provides a high-shielding insulating matte black ink, which includes the following components by mass percentage: 8-10% carbon black, 15-25% polyester resin, 0-3% matte powder, 1-3% filler, 1-5% additives, 3-5% blocked isocyanate curing agent, 1-3% acrylonitrile thermally expandable microspheres, 15-30% methyl ethyl ketone, 5-15% n-propyl acetate, 10-20% ethyl acetate, wherein the acrylonitrile thermally expandable microspheres include microspheres with particle sizes of 10 microns and 30 microns.

[0023] Furthermore, the filler is one or a combination of nano calcium carbonate and barium sulfate.

[0024] Furthermore, the additives are a mixture of one or more of a dispersant and an organosilicon leveling agent.

[0025] Furthermore, the ratio of the acrylonitrile thermally expandable microspheres with a particle size of 10 microns to the acrylonitrile thermally expandable microspheres with a particle size of 30 microns is 1.1-1.3:1.7-1.9.

[0026] A preparation method of a high-shielding insulating matte black ink includes the following steps:

[0027] Step 1: Mix methyl ethyl ketone, n-propyl acetate and ethyl acetate evenly to obtain a mixed solvent;

[0028] Step 2: Add carbon black, filler, additives such as a dispersant, etc. to the mixed solvent while dispersing them in turn, and disperse them at a high speed at a rotation speed of 1200-1500 revolutions per minute for 30-40 minutes to obtain a mixed material;

[0029] Step 3: Grind the mixed material through a sand mill until the fineness of the ink is less than 20 microns;

[0030] Step 4: Add the silica powder, thermally expandable microspheres and blocked isocyanate curing agent while dispersing, and then disperse at a high speed of 1200 - 1500 revolutions per minute for 15 - 20 minutes to fully mix the materials, and filter to obtain a highly light-shielding, insulating, matte black ink.

[0031] Furthermore, the ratio of the acrylonitrile thermally expandable microspheres with a particle size of 10 μm to the acrylonitrile thermally expandable microspheres with a particle size of 30 μm is 1.2:1.8.

[0032] Test according to different component ratios and adjust individual components. The main difference component ratios of each example are shown in the following table:

[0033]

[0034] For the inks configured or selected according to the above Examples 1 - 5, the performances of each example are detected as shown in the following table:

[0035] Detection indicators Example 1 Example 2 Example 3 Example 4 Example 5 Glossiness 1.5 2 1.2 0.9 0.9 Resistance value (Ω) <![CDATA[10 10 > <![CDATA[10 11 > <![CDATA[10 12 > <![CDATA[10 12 > <![CDATA[10 12 > Transmittance (%) 5 6 5 5 3 Adhesion (%) 90 98 100 100 100 Ink deterioration time (days) 1 1 1 >180 >180

[0036] Among them, Example 1 is a conventional highly light-shielding, insulating, matte black ink. Its gloss cannot effectively reach below 1. The resistance is small because too much silica powder and carbon black are added. The adhesion also becomes small because there is more powder and less resin. And because isocyanate curing agent is added to the ink, the ink will thicken and deteriorate after 1 day.

[0037] In Example 2, ordinary polymer plastic microspheres are used to replace part of the silica powder. Although the resistance can be reduced slightly, the degree of matteness cannot effectively meet the standard, and the shelf life of the ink is not long either.

[0038] In Example 3, 30μ thermally expandable microspheres are used to replace part of the silica powder and fillers. The surface unevenness caused by the expansion of the thermally expandable microspheres on the printing press results in a relatively low degree of matteness. At the same time, the expanded holes cause the resistance to increase. Except for the short shelf life, all other indicators basically meet the standard.

[0039] In Examples 4 and 5, two kinds of thermally expandable microspheres are mixed on the basis of Example 3, and at the same time, a blocked curing agent is used, which greatly improves the shelf life of the ink, and all its performance parameters can meet the standard.

[0040] The present invention uses heat-expandable microspheres (expansion temperature 80-90 degrees) instead of silicon dioxide to be added to the black ink formula. The temperature of the drying oven (100-110 degrees) during printing is used to make the ink film surface uneven due to the expansion of the heat-expandable microspheres to achieve a matte effect. Since this matte effect does not require the participation of matte powder, the proportion of resin and powder (carbon black, matte powder, filler, etc.) in the black ink formula is greater than that of the traditional black ink formula that requires the addition of a lot of matte powder and filler, thereby having excellent adhesion. At the same time, the expanded microspheres form a large number of cavities in the ink film layer to store air, thereby improving the insulation of the ink layer.

[0041] The heat-expandable microspheres used in the present invention have two particle sizes (10 microns and 30 microns). The microspheres of two different particle sizes produce uneven rough surfaces after expansion, and the matte effect caused is significantly better than the matte effect of using a single particle size.

[0042] The blocked isocyanate curing agent used in the present invention has an unblocking temperature of 90-100 degrees. After the ink is printed on the substrate and passes through the drying oven of the printing machine, it is unblocked by utilizing the temperature of the drying oven (100-110 degrees), so that the blocked curing agent containing isocyanate active groups undergoes a cross-linking and curing reaction with the ink, thereby further improving the adhesion of the black ink to the substrate.

[0043] It is worth mentioning that the technical features such as dispersants and silicone leveling agents involved in the patent application of this invention should be regarded as prior art. The specific structure, working principle and possible control method and spatial arrangement method of these technical features can be selected according to the conventional methods in the field, and should not be regarded as the inventive point of this patent. This patent will not be further elaborated.

[0044] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high light-shielding insulating matte black ink, characterized in that: The invention comprises the following components in percentage by mass: 8-10% carbon black, 15-25% polyester resin, 0-3% matte powder, 1-3% filler, 1-5% auxiliary agent, 3-5% blocked isocyanate curing agent, 1-3% acrylonitrile heat-expandable microspheres, 15-30% butanone, 5-15% n-propyl acetate, and 10-20% ethyl acetate, wherein the acrylonitrile heat-expandable microspheres comprise microspheres with particle sizes of 10 microns and 30 microns.

2. The high light-shielding insulating matte black ink according to claim 1, characterized in that: The filler is one of nano calcium carbonate and barium sulfate or a combination thereof.

3. The high light-shielding insulating matte black ink according to claim 1, characterized in that: The auxiliary agent is a dispersant, an organosilicon leveling agent or a mixture of more than one thereof.

4. The high light-shielding insulating matte black ink according to claim 1, characterized in that: The ratio of the acrylonitrile heat-expandable microspheres with a particle size of 10 microns to the acrylonitrile heat-expandable microspheres with a particle size of 30 microns is 1.1-1.3:1.7-1.

9.

5. A method for preparing a high light-shielding insulating matte black ink according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Evenly mix butanone, n-propyl acetate and ethyl acetate to obtain a mixed solvent; Step 2: Add carbon black, filler, dispersant and other additives to the mixed solvent in sequence while dispersing, and disperse at a high speed of 1200-1500 rpm for 30-40 minutes to obtain a mixed material; Step 3: Grind the mixed material by a sand mill until the fineness of the ink is less than 20 microns; Step 4: Add matte powder, heat-expandable microspheres and blocked isocyanate curing agent while dispersing, and then disperse at a high speed of 1200-1500 rpm for 15-20 minutes to fully mix the materials, and filter to obtain high-shielding insulating matte black ink.

6. The method for preparing the high light-shielding insulating matte black ink according to claim 5, characterized in that: The ratio of the acrylonitrile heat-expandable microspheres with a particle size of 10 microns to the acrylonitrile heat-expandable microspheres with a particle size of 30 microns is 1.2:1.8.

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