Yellowing-resistant ink composition containing alkali-soluble resin and preparation method thereof

Abstract

The present invention provides an ink composition containing an alkali-soluble resin and being resistant to yellowing. The ink composition containing an alkali-soluble resin and being resistant to yellowing comprises a component A and a component B. The component A comprises the following components in mass fractions: a modified alkali-soluble resin, an active monomer, a photoinitiator, silicon dioxide, a pigment, a surfactant, and a divalent acid ester; the component B comprises the following components in mass fractions: an epoxy resin, an auxiliary agent, and a divalent acid ester. The present invention first partially grafts acrylic acid and linoleic acid onto silicon dioxide particles through the action of carboxyl groups and hydroxyl groups, respectively, to obtain modified acrylic acid and modified linoleic acid, and then obtains a modified alkali-soluble resin through free radical polymerization with ethyl methacrylate. The surface of the modified alkali-soluble resin is grafted with silicon dioxide particles, contains a large number of active groups such as hydroxyl groups and ester groups, and can form hydrogen bonds and covalent bonds with other components to achieve a stable anti-yellowing effect.

Description

Technical Field

[0001] The invention relates to the field of ink, and in particular to an ink composition containing an alkali-soluble resin and being resistant to yellowing, and a preparation method thereof. Background Art

[0002] With the development of social economy and the improvement of environmental awareness, people have higher and higher requirements for the performance of ink. As a permanent protective coating for large-area printing on circuit boards, ink should not only selectively mask the wires to prevent pattern damage and short circuits, but also have chemical resistance, solvent resistance, heat resistance, insulation, and prevent solder adhesion and copper contamination of the solder bath. Resin is a key component in the ink formulation, and its physical and chemical properties have a decisive influence on the overall performance of the ink. Therefore, the development and selection of appropriate resins are crucial to the manufacture of high-performance inks.

[0003] However, existing ink technology faces some challenges in practical applications. In particular, during long-term use, the ink may yellow due to environmental factors such as light, temperature changes, humidity, etc. This yellowing not only affects the appearance of the coating, but also may reduce its protective performance, thereby affecting the overall quality and reliability of the circuit board.

[0004] In summary, it is urgent to develop a new technical solution to solve the problems existing in the prior art. Summary of the invention

[0005] The present invention provides an ink composition containing an alkali-soluble resin and a preparation method thereof. The ink composition containing an alkali-soluble resin and a yellowing-resistant ink composition is composed of modified alkali-soluble resin, active monomers, photoinitiators and other components. The present invention first partially grafts acrylic acid and linoleic acid onto silica particles through the action of carboxyl and hydroxyl groups, respectively, to obtain modified acrylic acid and modified linoleic acid, and then obtains a modified alkali-soluble resin through free radical polymerization with ethyl methacrylate. The modified alkali-soluble resin contains a large number of alkali-soluble groups such as carboxyl groups, is suitable for alkaline water development, and is added to the ink composition to effectively reduce environmental pollution and broaden the scope of use; at the same time, the surface of the modified alkali-soluble resin is grafted with silica particles, contains a large number of active groups such as hydroxyl groups and ester groups, and can form hydrogen bonds and covalent bonds with other components to achieve a stable anti-yellowing effect.

[0006] An object of the present invention is to provide an ink composition containing an alkali-soluble resin and being resistant to yellowing. The ink composition containing an alkali-soluble resin and being resistant to yellowing comprises a component A and a component B.

[0007] The A component includes the following components in parts by mass:

[0008]

[0009]

[0010] The B component includes the following components in parts by mass:

[0011] Epoxy resin 1-10 parts

[0012] 1-10 parts of additives

[0013] 1-10 parts of dibasic acid ester;

[0014] in,

[0015] The modified alkali-soluble resin is a product obtained by free radical polymerization of modified acrylic acid, modified linoleic acid and ethyl methacrylate;

[0016] The modified acrylic acid is acrylic acid partially grafted with silica particles;

[0017] The modified linoleic acid is linoleic acid partially grafted with silicon dioxide particles.

[0018] Furthermore, the active monomer is an acrylate having a monofunctional group.

[0019] Furthermore, the molar ratio of the modified acrylic acid, modified linoleic acid and ethyl methacrylate is 1:1:1-1:3:5.

[0020] Furthermore, the surfactant is selected from one or more of Tween or Span surfactants.

[0021] Another object of the present invention is to provide a method for preparing the above-mentioned yellowing-resistant alkali-soluble resin ink composition, the method for preparing the yellowing-resistant alkali-soluble resin ink composition comprising the following steps:

[0022] S1, immersing the silicon dioxide particles in an aqueous solution of acrylic acid and ultrasonically heating them to obtain acrylic acid partially grafted with the silicon dioxide particles, i.e., modified acrylic acid;

[0023] S2, immersing the silicon dioxide particles in an aqueous solution of linoleic acid and ultrasonically heating them to obtain linoleic acid partially grafted with the silicon dioxide particles, i.e., modified linoleic acid;

[0024] S3, subjecting the modified acrylic acid, modified linoleic acid and ethyl methacrylate to free radical polymerization in toluene under the action of benzoyl peroxide, and removing the solvent to obtain a modified alkali-soluble resin;

[0025] S4. Blend and react a modified alkali-soluble resin, an active monomer, a photoinitiator, silica, a pigment, a surfactant and a divalent acid ester to obtain a component A; blend and react an epoxy resin, an auxiliary agent and a divalent acid ester to obtain a component B; then blend the components A and B, stir and disperse them evenly, grind and filter them to obtain a yellowing-resistant ink composition containing an alkali-soluble resin.

[0026] Furthermore, in step S1, the mass ratio of silicon dioxide to acrylic acid is 1:5-1:6.

[0027] Furthermore, in step S1, the heating condition is 70-90°C.

[0028] Furthermore, in step S2, the mass ratio of silicon dioxide to linoleic acid is 1:20-1:25.

[0029] Furthermore, in step S2, the heating condition is 70-90°C.

[0030] The present invention has the following beneficial effects:

[0031] The present invention discloses an ink composition containing an alkali-soluble resin and being resistant to yellowing, and a preparation method thereof. The ink composition containing an alkali-soluble resin and being resistant to yellowing is composed of components such as a modified alkali-soluble resin, an active monomer, and a photoinitiator. The present invention first partially grafts acrylic acid and linoleic acid onto silica particles through the action of carboxyl and hydroxyl groups, respectively, to obtain modified acrylic acid and modified linoleic acid, and then obtains a modified alkali-soluble resin through free radical polymerization with ethyl methacrylate. The modified alkali-soluble resin contains a large number of alkali-soluble groups such as carboxyl groups, is suitable for alkaline water development, and is added to the ink composition, which can effectively reduce environmental pollution and broaden the scope of use; at the same time, the silica particles grafted on its surface contain a large number of active groups such as hydroxyl groups and ester groups, which can form hydrogen bonds and covalent bonds with other components to achieve a stable anti-yellowing effect. DETAILED DESCRIPTION

[0032] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0033] The words "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not applicable, nor is it intended to exclude other embodiments from the scope of the present invention.

[0034] It should be understood that, except in any operating examples, or where otherwise indicated, all numbers indicating, for example, the amounts of ingredients used in the specification and claims should be understood to be modified in all cases by the term "about". Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that vary depending on the desired properties to be obtained by the present invention.

[0035] The present invention uses the following raw materials:

[0036] The Tween 80 used in the examples and comparative examples of the present invention is PB01659, purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.

[0037] The photoinitiator in the embodiments and comparative examples of the present invention is photoinitiator 819.

[0038] The additives in the embodiments and comparative examples of the present invention are toner, leveling agent and dispersant in a mass ratio of 1:1:2. The toner is titanium dioxide, the leveling agent is isopropyl alcohol, and the dispersant is sodium dodecyl sulfate.

[0039] The epoxy resin in the embodiments and comparative examples of the present invention is hydrogenated bisphenol A epoxy resin with the brand name HE4080E, a viscosity of 2300 cps@25°C, and an epoxy equivalent of 210-230 g / eq, purchased from Luohe High-tech Materials (Shanghai) Co., Ltd.

[0040] Example 1

[0041] A yellowing-resistant ink composition containing an alkali-soluble resin, the yellowing-resistant ink composition containing an alkali-soluble resin comprising a component A and a component B,

[0042] The A component includes the following components in parts by mass:

[0043]

[0044]

[0045] The B component includes the following components in parts by weight:

[0046] Epoxy resin 5 parts

[0047] 5 parts of additives

[0048] 5 parts of dibasic acid ester.

[0049] The method for preparing the above-mentioned yellowing-resistant alkali-soluble resin ink composition comprises the following steps:

[0050] S1, immersing silica particles in an aqueous solution of acrylic acid (silicon dioxide: acrylic acid = 1:5, m / m), ultrasonically dispersing at 70° C. for 10 h, filtering, washing, and drying to obtain acrylic acid partially grafted with silica particles, i.e., modified acrylic acid;

[0051] S2, immersing the silica particles in an aqueous solution of linoleic acid (silicon dioxide: linoleic acid = 1:20, m / m), ultrasonically dispersing at 70° C. for 10 h, filtering, washing, and drying to obtain linoleic acid partially grafted with silica particles, i.e., modified linoleic acid;

[0052] S3, blending the modified acrylic acid, modified linoleic acid and ethyl methacrylate, and subjecting the mixture to free radical polymerization in toluene under the action of benzoyl peroxide (modified acrylic acid: modified linoleic acid: ethyl methacrylate: benzoyl peroxide = 1:1:3:0.01, m / m / m / m), and removing the solvent to obtain a modified alkali-soluble resin;

[0053] S4. According to the above-mentioned mass fractions, the modified alkali-soluble resin, methyl acrylate, photoinitiator, silica, pigment, Tween 80 and dibasic acid ester are blended and reacted to obtain component A; the epoxy resin, auxiliary agent and dibasic acid ester are blended and reacted to obtain component B; then the components A and B are blended, stirred and dispersed evenly, ground to a fineness of ≤20 μm, and passed through a 120-mesh sieve to obtain a yellowing-resistant ink composition containing an alkali-soluble resin.

[0054] Example 2

[0055] A yellowing-resistant ink composition containing an alkali-soluble resin, the yellowing-resistant ink composition containing an alkali-soluble resin comprising a component A and a component B,

[0056] The A component includes the following components in parts by mass:

[0057]

[0058]

[0059] The B component includes the following components in parts by weight:

[0060] Epoxy resin 10 parts

[0061] 10 parts of additives

[0062] 10 parts of dibasic acid ester.

[0063] The preparation method of the above-mentioned yellowing-resistant alkali-soluble resin ink composition is the same as that of Example 1.

[0064] Example 3

[0065] A yellowing-resistant ink composition containing an alkali-soluble resin, the yellowing-resistant ink composition containing an alkali-soluble resin comprising a component A and a component B,

[0066] The A component includes the following components in parts by mass:

[0067]

[0068] The B component includes the following components in parts by weight:

[0069] Epoxy resin 8 parts

[0070] 5 parts of additives

[0071] 8 parts of dibasic acid ester.

[0072] The preparation method of the above-mentioned yellowing-resistant alkali-soluble resin ink composition is the same as that of Example 1.

[0073] Comparative Example 1

[0074] A yellowing-resistant ink composition containing an alkali-soluble resin. The difference between this comparative example and Example 1 is that step S1 is omitted, and in step S3, the mass of modified acrylic acid is replaced by unmodified acrylic acid, and the amounts of other components and the preparation method are the same as those in Example 1.

[0075] Comparative Example 2

[0076] A yellowing-resistant ink composition containing an alkali-soluble resin. The difference between this comparative example and Example 1 is that step S2 is omitted, and in step S3, the mass of modified linoleic acid is replaced by unmodified linoleic acid, and the amounts of other components and the preparation method are the same as those in Example 1.

[0077] Test Case

[0078] The performance of the yellowing-resistant alkali-soluble resin-containing ink compositions prepared in Examples 1-3 and Comparative Examples 1-2 was tested.

[0079] The test method is as follows:

[0080] The yellowing-resistant alkali-soluble resin ink compositions prepared in the examples and comparative examples were coated on PCB boards and photocured for 1 h (wavelength 395 nm, intensity 25.0 mW / cm 2 The film was then cured at 150 °C for 1 h to form a 0.5 mm thick film.

[0081] Pencil hardness: measured in accordance with JIS K5400.

[0082] Adhesion: Use a needle tip to make an "X" on the film, then stick a cellophane tape on the cut and pull it, and evaluate based on the following criteria:

[0083] Excellent: Not torn off;

[0084] Poor: Extensive tear-off.

[0085] Bending resistance: Bend 180° with the solder mask film on the outside and evaluate based on the following criteria:

[0086] Excellent: No cracks on the film;

[0087] Poor: There are cracks on the film.

[0088] Acid resistance: At 20°C, PCBs coated with an ink composition containing an alkali-soluble resin and yellowing resistance were immersed in a 10% sulfuric acid solution. After 30 minutes, the PCBs were taken out and the coating state and adhesion were evaluated. The criteria for determination were as follows:

[0089] Pass: No change or slight change was found;

[0090] Unqualified: There is swelling or shedding on the coating film.

[0091] Heat resistance: Thermal shock performance test is carried out according to the method in IPC-SM-840E, and the judgment criteria are as follows:

[0092] Qualified: no bubbles or cracks;

[0093] Unqualified: bubbles and cracks appear.

[0094] Hot and cold cycle shock:

[0095] First, pre-treatment is performed: after placing at 125°C for 24 hours, place at 60°C and 60% RH for 52 hours; then, hot and cold conditions are cycled: after placing at -65°C for 15 minutes, place at 150°C for 15 minutes, and so on. The switching time is <10s and the number of cycles is 1000. The judgment criteria are as follows:

[0096] Qualified: No cracking, falling off, etc.

[0097] Unqualified: cracking and falling off.

[0098] Anti-yellowing performance: The reflectivity of the sample was measured after reflow soldering for three times. The reflow soldering conditions were: 190℃*3min, 220℃*2min, 240℃*3min, 280℃*4min, for a total of 12min.

[0099] The test instrument used is X-RITE colorimeter model SP62. The larger the △B value, the more serious the yellowing.

[0100] The test results are shown in Table 1.

[0101] Table 1 Performance test results

[0102]

[0103]

[0104] It can be seen from the above test results that the various properties of the yellowing-resistant alkali-soluble resin-containing ink composition prepared in the embodiment of the present invention are significantly better than those of comparative examples 1-2, indicating that the addition of the modified alkali-soluble resin of the present invention can synergize with other components to improve the anti-yellowing performance of the ink composition; while comparative examples 1-2 replaced the modified acrylic acid or modified linoleic acid, resulting in weakened interaction between components, decreased stability, and poor anti-yellowing performance.

[0105] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0106] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A yellowing-resistant ink composition containing an alkali-soluble resin, characterized in that: The yellowing-resistant alkali-soluble resin-containing ink composition comprises component A and component B, The A component includes the following components in parts by mass: 50-60 parts of modified alkali-soluble resin Active monomer 30-40 parts Photoinitiator 1-2 parts 20-30 parts of silicon dioxide 3-5 parts of pigment 3-5 parts surfactant 40-60 parts of dibasic acid ester; The B component includes the following components in parts by mass: Epoxy resin 1-10 parts 1-10 parts of additives 1-10 parts of dibasic acid ester; in, The modified alkali-soluble resin is a product obtained by free radical polymerization of modified acrylic acid, modified linoleic acid and ethyl methacrylate; The modified acrylic acid is acrylic acid partially grafted with silica particles; The modified linoleic acid is linoleic acid partially grafted with silica particles; The active monomer is an acrylate having a monofunctional group; The molar ratio of the modified acrylic acid, modified linoleic acid and ethyl methacrylate is 1:1:1-1:3:

5.

2. The yellowing-resistant alkali-soluble resin-containing ink composition according to claim 1, characterized in that: The surfactant is selected from one or more of Tween or Span surfactants.

3. The method for preparing the yellowing-resistant alkali-soluble resin ink composition according to any one of claims 1 to 2, characterized in that: The method for preparing the yellowing-resistant alkali-soluble resin ink composition comprises the following steps: S1, immersing the silicon dioxide particles in an aqueous solution of acrylic acid and ultrasonically heating them to obtain acrylic acid partially grafted with the silicon dioxide particles, i.e., modified acrylic acid; S2, immersing the silicon dioxide particles in an aqueous solution of linoleic acid and ultrasonically heating them to obtain linoleic acid partially grafted with the silicon dioxide particles, i.e., modified linoleic acid; S3, subjecting the modified acrylic acid, modified linoleic acid and ethyl methacrylate to free radical polymerization in toluene under the action of benzoyl peroxide, and removing the solvent to obtain a modified alkali-soluble resin; S4. Blend and react a modified alkali-soluble resin, an active monomer, a photoinitiator, silica, a pigment, a surfactant and a divalent acid ester to obtain a component A; blend and react an epoxy resin, an auxiliary agent and a divalent acid ester to obtain a component B; then blend the components A and B, stir and disperse them evenly, grind and filter them to obtain a yellowing-resistant ink composition containing an alkali-soluble resin.

4. The method for preparing the yellowing-resistant alkali-soluble resin ink composition according to claim 3, characterized in that: In step S1, the mass ratio of silicon dioxide to acrylic acid is 1:5-1:

6.

5. The method for preparing the yellowing-resistant alkali-soluble resin ink composition according to claim 3, characterized in that: In step S1, the heating condition is 70-90°C.

6. The method for preparing the yellowing-resistant alkali-soluble resin ink composition according to claim 3, characterized in that: In step S2, the mass ratio of silicon dioxide to linoleic acid is 1:20-1:

25.

7. The method for preparing the yellowing-resistant alkali-soluble resin ink composition according to claim 3, characterized in that: In step S2, the heating condition is 70-90°C.

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