UV-LED curing inkjet, and preparation method and application thereof

Abstract

The application discloses a kind of UV-LED solidification ink-jet and its preparation method and application.It is related to the technical field of solidification ink.The raw material of the above-mentioned solidification ink-jet includes the following components by weight: photoinitiator 7-10 parts;UV monomer 50-75 parts;oligomer 5-10 parts;thermal curing agent 2-8 parts.Through the reasonable proportion of photoinitiator, UV monomer, oligomer and thermal curing agent, a relatively close polymer network structure is formed, and the selection of UV monomer and oligomer will further promote intermolecular attraction, so that the surface tension increases, and the surface tension of the ink after solidification is higher.

Description

Technical Field

[0001] This invention relates to the field of curing ink technology, and in particular to a UV-LED curing inkjet, its preparation method, and its application. Background Technology

[0002] PCB (Printed Circuit Board) is the connector and carrier of electronic components. Characters are printed on PCBs to facilitate subsequent inspection, repair, or installation. Traditional thermosetting character inks are produced using screen printing, a process with many steps, long cycles, and defects such as ghosting and blurring. Furthermore, organic solvents are generally required for dilution, resulting in wastewater and VOC emissions, and the stencil needs cleaning at the end. Inkjet printing combined with UV-LED curing is driving a technological revolution in PCB production. Inkjet printing is a screenless, contactless printing technology controlled by computer programs, achieving on-demand printing with high ink utilization. UV curing requires no volatile solvents; UV inkjet printing is VOC-free, making it more environmentally friendly than traditional screen printing inks. In recent years, PCB production has gradually shifted towards automation, with semi-automatic production lines for circuit ink coating and solder resist screen printing emerging. Character inks have taken the lead in this shift, adopting an inkjet printing and UV curing process, significantly improving production efficiency while reducing the error rate of manual operation.

[0003] Character ink is an important component of circuit boards. Besides basic performance requirements such as adhesion, hardness, high-temperature resistance, and resistance to yellowing, to ensure good printability, it also needs low viscosity, good storage stability, and stable particle size (no agglomeration). Finally, surface tension is also important: before the ink droplets from the printhead land on the substrate, high surface tension ink facilitates droplet tail shrinkage, resulting in a relatively full printed pattern and smooth lines; when printing on the substrate, low surface tension ink helps the droplets wet and spread on the substrate, preventing abnormal shrinkage.

[0004] Currently, the requirements for mid-to-high-end PCB manufacturing are becoming increasingly stringent. For example, end customers of new energy vehicle PCBs continue to print (barcodes, QR codes) on the finished white ink blocks or apply conformal coating to the entire board. This requires the surface tension of the white ink blocks to reach 32 mN / m or higher, and some end customers even require 38 mN / m or higher, to ensure: 1. Adhesive adhesion and no peeling of the printed code on the white ink blocks; 2. Uniform spread of the conformal coating on the entire board without localized shrinkage, unevenness, or other abnormalities. Among the various brands of PCB solder resist inks on the market, matte solder resist inks have a higher surface tension (32-42 mN / m), while glossy solder resist inks have a relatively lower surface tension (24-32 mN / m). This leads to a contradiction in the character production process: developing character inks that meet high surface tension requirements results in the abnormal phenomenon of ink shrinkage when applied to low-tension solder resist inks.

[0005] Therefore, there is an urgent need to develop a UV inkjet printer with high surface tension after curing, in order to provide a high surface tension to meet the process requirements of subsequent coding or conformal coating. Summary of the Invention

[0006] The first technical problem to be solved by this invention is:

[0007] A curing inkjet is provided.

[0008] The second technical problem to be solved by this invention is:

[0009] A method for preparing the curing inkjet is provided.

[0010] The third technical problem to be solved by this invention is:

[0011] The application of curing inkjet.

[0012] To solve the first technical problem, the technical solution adopted by the present invention is as follows:

[0013] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0014] 7-10 parts of photoinitiator;

[0015] 50-75 parts of UV monomer;

[0016] 5-10 parts of oligomer;

[0017] 2 to 8 parts of thermosetting agent.

[0018] According to embodiments of the present invention, one of the technical solutions has at least one of the following advantages or beneficial effects:

[0019] The curing inkjet, through a reasonable ratio of photoinitiator, UV monomer, oligomer and thermosetting agent, promotes the formation of a relatively compact polymer network structure. The selection of UV monomer and oligomer further promotes the mutual attraction between molecules, which increases the surface tension and thus makes the surface tension of the cured ink higher.

[0020] According to one embodiment of the present invention, the photoinitiator includes at least one selected from 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoylphenylphosphine acid, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-isopropylthioxanthone, and ethyl 4-dimethylaminobenzoate.

[0021] According to one embodiment of the present invention, the UV monomer includes monofunctional monomers, difunctional monomers, and trifunctional monomers.

[0022] According to one embodiment of the present invention, the weight ratio of the monofunctional monomer to the difunctional monomer is 15-30:15-40.

[0023] According to one embodiment of the present invention, the weight ratio of the monofunctional monomer to the trifunctional monomer is 15-30:5-25.

[0024] According to one embodiment of the present invention, the weight ratio of the monofunctional monomer, difunctional monomer, and trifunctional monomer is 20-25: 25-35: 8-20.

[0025] Among UV monomers, monofunctional, difunctional, and trifunctional monomers possess different functional groups, which influence the interactions between ink molecules. For example, multifunctional monomers can form more cross-linked structures, thereby enhancing the intermolecular attraction, while monofunctional monomers may result in fewer cross-linked structures and weaker intermolecular attraction.

[0026] Furthermore, the weight ratio of monofunctional, difunctional, and trifunctional monomers affects the proportion of different functional groups in the ink and the interaction forces between ink molecules. The proportion of different functional groups influences the structure of the ink molecules. Multifunctional monomers may form more complex molecular structures, while monofunctional monomers may have simpler molecular structures. These structural differences affect the arrangement and morphology of ink molecules on the surface, thus affecting surface tension. Different types of functional groups can influence the interaction forces between ink molecules, such as hydrogen bonds and van der Waals forces. These interaction forces affect the aggregation state of ink molecules and surface tension.

[0027] According to one embodiment of the present invention, the monofunctional monomer includes at least one of vinyl active monomers, cyclohexyl acrylate monomers, and hydroxyl-containing acrylate monomers.

[0028] According to one embodiment of the present invention, the vinyl active monomer includes at least one of ACMO (N-acryloylmorpholine), DMMA (N,N-dimethylacrylamide), and DEAA (N,N-diethylacrylamide).

[0029] Different vinyl reactive monomers react differently with other components during photopolymerization, forming different cross-linked structures. These cross-linked structures affect the intermolecular interactions and surface tension of the ink. Some vinyl reactive monomers may lead to the formation of more cross-linking points, which enhances the attraction between ink molecules and thus reduces surface tension.

[0030] According to one embodiment of the present invention, ACMO is a vinyl reactive monomer containing an acryloylmorpholine functional group. During photopolymerization, it can undergo polymerization with compounds containing active hydrogen to form a cross-linked structure. For example, a cross-linking reaction occurs when ACMO reacts with oligomers containing active hydrogen.

[0031] According to one embodiment of the present invention, DMMA is a vinyl reactive monomer containing a methacrylamide functional group. It can copolymerize with other vinyl reactive monomers in the components to form copolymers. For example, DMMA can copolymerize with other vinyl reactive monomers such as DEAA.

[0032] According to one embodiment of the present invention, DEAA is a vinyl reactive monomer containing an ethylacrylamide functional group. During photopolymerization, it can react with a photoinitiator to initiate the polymerization reaction. The photoinitiator can initiate the polymerization of the vinyl reactive monomer by releasing reactants such as free radicals or ions, thereby promoting the curing of the ink.

[0033] According to one embodiment of the present invention, at least one of the cyclohexyl acrylate monomers TBCHA (4-tert-butylcyclohexyl acrylate) and TMCHA (3,3,5-trimethylcyclohexyl acrylate) is used.

[0034] According to one embodiment of the present invention, the hydroxyl-containing acrylic monomer is at least one of 4-HBA (4-hydroxybutyl acrylate), CA (caprolactone acrylate), and HEMA (2-hydroxyethyl acrylate).

[0035] According to one embodiment of the present invention, the bifunctional monomer includes at least one of HDDA (1,6-hexanediol diacrylate), TPGDA (tripropylene glycol diacrylate), DPGDA (dipropylene glycol diacrylate), NPGDA (neopentyl glycol diacrylate), NPG(PO)2DA (2(propoxy)neopentyl glycol diacrylate), and TTEGDA (tetraethylene glycol diacrylate).

[0036] According to one embodiment of the present invention, the monofunctional monomer includes ACMO and CA.

[0037] According to one embodiment of the present invention, the bifunctional monomer includes HDDA and NPG(PO)2DA.

[0038] According to one embodiment of the present invention, the trifunctional monomer includes at least one of TMPTA (trimethylolpropane triacrylate), 3EO-TMPTA (3(ethoxy)trimethylolpropane triacrylate), GPTA (propoxylated glycerol triacrylate), and PET3A (pentaerythritol triacrylate).

[0039] According to one embodiment of the present invention, the oligomer includes at least one of ethoxylated bisphenol A diacrylate and ethoxylated bisphenol F diacrylate.

[0040] According to one embodiment of the present invention, the ethoxylated bisphenol A diacrylate has the chemical name BPA(EO). n DA, where n = 3, 4, 8, 10, 20, 30.

[0041] Select ethoxylated bisphenol A diacrylate (BPA(EO)) with different degrees of polymerization (n value) n As an oligomer, DA (dimer-dependent polymers) affects the surface tension and surface free energy of UV-LED cured inks. This is because different degrees of polymerization affect the molecular structure and properties of the oligomer, thus influencing the interactions between ink molecules and surface properties. Furthermore, choosing oligomers with different degrees of polymerization affects the surface tension of the ink. Generally, oligomers with higher degrees of polymerization lead to increased intermolecular attraction, resulting in lower surface tension. Therefore, choosing oligomers with higher degrees of polymerization (larger n-values) may result in lower surface tension. The degree of polymerization also affects the surface free energy after ink curing. After curing, surface free energy refers to the energy state of ink molecules on the surface; lower surface free energy means that ink molecules are more stable on the surface. Oligomers with higher degrees of polymerization may have more complex molecular structures, forming more stable network structures, resulting in lower surface free energy after ink curing.

[0042] In summary, selecting ethoxylated bisphenol A diacrylate (BPA(EO)nDA) with different degrees of polymerization as oligomers affects the surface tension and surface free energy of UV-LED cured inks. Oligomers with higher degrees of polymerization may reduce the surface tension of the ink and result in a lower surface free energy after curing, contributing to a more stable surface state. Choosing an appropriate degree of polymerization allows for adjustments to the ink's performance and surface characteristics based on specific application requirements.

[0043] According to one embodiment of the present invention, the ethoxylated bisphenol F diacrylate has the chemical name BPF(EO). n DA, where n = 4, 6, 8, 10, 15, 20, 30.

[0044] Choosing different types of oligomers (such as ethoxylated bisphenol A diacrylate or ethoxylated bisphenol F diacrylate) affects the surface tension and surface free energy of UV-LED cured inks. Because ethoxylated bisphenol A diacrylate and ethoxylated bisphenol F diacrylate have different chemical structures, their interactions with other components also differ. These interactions can affect the arrangement and surface state of ink molecules, thus influencing the surface tension of the ink. Furthermore, the choice of oligomer also affects the surface free energy of the cured ink. Surface free energy refers to the energy state of ink molecules on the surface after curing. Different types of oligomers may form different types of network structures, resulting in different surface free energies after ink curing.

[0045] According to one embodiment of the present invention, the thermosetting agent comprises isocyanate.

[0046] According to one embodiment of the present invention, the isocyanate includes LANXESS isocyanate.

[0047] According to one embodiment of the present invention, the LANXESS isocyanate includes at least one of Txiene BI 7981, Txiene BI 7984, Txiene BI 7991, and Txiene BI 7992.

[0048] According to one embodiment of the present invention, the curing inkjet further includes the following components: color paste and additives, wherein the color paste includes acrylic monomer, titanium dioxide and dispersant.

[0049] According to one embodiment of the present invention, the color paste comprises 20-25 parts acrylic monomer, 65-70 parts titanium dioxide and 5-8 parts dispersant.

[0050] According to one embodiment of the present invention, the acrylic monomer includes at least one of 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, and neopentyl glycol diacrylate.

[0051] According to one embodiment of the present invention, the titanium dioxide includes at least one of Melilink 595, Melilink R-105, DuPont 706, Ishihara CR-50, and Ishihara R-980.

[0052] According to one embodiment of the present invention, the dispersant in the color paste component includes at least one of BYKJET-9150, BYKJET-9151, and BYKJET-9152 from BYKJET; BASF efka 4310, BASF efka 4330, BASF efka PX4701, and BASF efka PX7701 from BASF; and Lubrizol Solsperse 39000, Solsperse 36000, Solsperse 28000, and Solsperse 24000 from Lubrizol.

[0053] According to one embodiment of the present invention, the additive is a leveling additive, including at least one of TEGO 410, TEGO 432, TEGO 425, TEGO 2200n, TEGO 2300 from TIGAL, and BYK 307, BYK 377, BYK 379, BYK 3500, and BYK 361n from BYK.

[0054] To solve the second technical problem, the technical solution adopted by the present invention is as follows:

[0055] A method for preparing the cured inkjet printer includes the following steps:

[0056] A curable inkjet printer is obtained by mixing a photoinitiator, a UV monomer, an oligomer, and a thermosetting agent.

[0057] In another aspect, the present invention provides a PCB solder resist ink, comprising the aforementioned curing inkjet. Since this application employs all the technical solutions of the above-described curing inkjet, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments.

[0058] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Detailed Implementation

[0059] In the description of this invention, the use of terms such as "first," "second," etc., is for the purpose of distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or implicitly indicating the order of the technical features indicated.

[0060] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the embodiments, and are only for the purpose of facilitating the description of this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0061] The terms "preferred," "more preferably," etc., used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.

[0062] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0063] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of the present invention.

[0064] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in this technical field.

[0065] Example 1

[0066] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0067]

[0068] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0069] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0070] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0071] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0072] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0073] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0074] The thermosetting agent is Txiene BI 7981.

[0075] The nano-white paste comprises the following components by weight percentage:

[0076] HDDA 27.5%

[0077] Meililian 595 67.5%

[0078] BASF efka 4310 5%.

[0079] The additive is BYK 377.

[0080] The steps for preparing the above-mentioned nano-white paste are as follows:

[0081] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0082] The preparation of the above-mentioned curable inkjet includes the following steps:

[0083] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0084] Example 2

[0085] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0086]

[0087] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0088] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:12.

[0089] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0090] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0091] The trifunctional monomer is TMPTA, with a weight of 12 parts.

[0092] The oligomer in question is BPA(EO). n DA, where n = 10, has a surface tension of 44.0 mN / m.

[0093] The thermosetting agent is Txiene BI 7981.

[0094] The nano-white paste comprises the following components by weight percentage:

[0095] HDDA 27.5%

[0096] Meililian 595 67.5%

[0097] BASF efka 4310 5%.

[0098] The additive is BYK 377.

[0099] The steps for preparing the above-mentioned nano-white paste are as follows:

[0100] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0101] The preparation of the above-mentioned curable inkjet includes the following steps:

[0102] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0103] Example 3

[0104] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0105]

[0106] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0107] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:10.

[0108] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0109] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0110] The trifunctional monomer is TMPTA, with a weight of 10 parts.

[0111] The oligomer in question is BPA(EO). n DA, where n = 20, has a surface tension of 44.4 mN / m.

[0112] The thermosetting agent is Txiene BI 7981.

[0113] The nano-white paste comprises the following components by weight percentage:

[0114] HDDA 27.5%

[0115] Meililian 595 67.5%

[0116] BASF efka 4310 5%.

[0117] The additive is BYK 377.

[0118] The steps for preparing the above-mentioned nano-white paste are as follows:

[0119] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0120] The preparation of the above-mentioned curable inkjet includes the following steps:

[0121] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0122] Example 4

[0123] The difference between Example 4 and Example 3 is that the oligomer in Example 4 is BPF(EO). n DA, where n=4, has a viscosity of 550-750 cps; Example 3 shows that the oligomer is BPA(EO). n DA, where n = 20, has a viscosity of 500-700 cps.

[0124] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0125]

[0126] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0127] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:10.

[0128] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0129] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0130] The trifunctional monomer is TMPTA, with a weight of 10 parts.

[0131] The oligomer in question is BPF(EO). n DA, where n = 4, has a surface tension of 44.2 mN / m.

[0132] The thermosetting agent is Txiene BI 7981.

[0133] The nano-white paste comprises the following components by weight percentage:

[0134] HDDA 27.5%

[0135] Meililian 595 67.5%

[0136] BASF efka 4310 5%.

[0137] The additive is BYK 377.

[0138] The steps for preparing the above-mentioned nano-white paste are as follows:

[0139] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0140] The preparation of the above-mentioned curable inkjet includes the following steps:

[0141] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0142] Comparative Example 1

[0143] The difference between Comparative Example 1 and Example 1 is that all the trifunctional monomers in Comparative Example 1 are made of GPTA.

[0144] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0145]

[0146] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0147] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0148] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0149] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0150] The trifunctional monomer is GPTA, with a weight of 15 parts.

[0151] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0152] The thermosetting agent is Txiene BI 7981.

[0153] The nano-white paste comprises the following components by weight percentage:

[0154] HDDA 27.5%

[0155] Meililian 595 67.5%

[0156] BASF efka 4310 5%.

[0157] The additive is BYK 377.

[0158] The steps for preparing the above-mentioned nano-white paste are as follows:

[0159] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0160] The preparation of the above-mentioned curable inkjet includes the following steps:

[0161] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0162] Comparative Example 2

[0163] The difference between Comparative Example 2 and Example 1 is that all the bifunctional monomers in Comparative Example 2 are HDDA.

[0164] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0165]

[0166] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0167] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0168] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0169] The bifunctional monomer is HDDA, with a weight of 30 parts.

[0170] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0171] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0172] The thermosetting agent is Txiene BI 7981.

[0173] The nano-white paste comprises the following components by weight percentage:

[0174] HDDA 27.5%

[0175] Meililian 595 67.5%

[0176] BASF efka 4310 5%.

[0177] The additive is BYK 377.

[0178] The steps for preparing the above-mentioned nano-white paste are as follows:

[0179] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0180] The preparation of the above-mentioned curable inkjet includes the following steps:

[0181] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0182] Comparative Example 3

[0183] The difference between Comparative Example 3 and Example 1 is that the monofunctional monomers in Comparative Example 3 include DMMA and CA.

[0184] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0185]

[0186] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0187] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0188] The monofunctional monomers include DMMA and CA, with a weight ratio of DMMA to CA of 14:10, totaling 24 parts;

[0189] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0190] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0191] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0192] The thermosetting agent is Txiene BI 7981.

[0193] The nano-white paste comprises the following components by weight percentage:

[0194] HDDA 27.5%

[0195] Meililian 595 67.5%

[0196] BASF efka 4310 5%.

[0197] The additive is BYK 377.

[0198] The steps for preparing the above-mentioned nano-white paste are as follows:

[0199] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0200] The preparation of the above-mentioned curable inkjet includes the following steps:

[0201] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0202] Comparative Example 4

[0203] The difference between Comparative Example 4 and Example 1 is that the monofunctional monomers in Comparative Example 4 include TBCHA and CA.

[0204] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0205]

[0206] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0207] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0208] The monofunctional monomers include TBCHA and CA, with a weight ratio of 14:10 for TBCHA and CA, totaling 24 parts.

[0209] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0210] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0211] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0212] The thermosetting agent is Txiene BI 7981.

[0213] The nano-white paste comprises the following components by weight percentage:

[0214] HDDA 27.5%

[0215] Meililian 595 67.5%

[0216] BASF efka 4310 5%.

[0217] The additive is BYK 377.

[0218] The steps for preparing the above-mentioned nano-white paste are as follows:

[0219] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0220] The preparation of the above-mentioned curable inkjet includes the following steps:

[0221] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0222] Comparative Example 5

[0223] The difference between Comparative Example 5 and Example 1 is that the monofunctional monomers in Comparative Example 5 include TMCHA and CA.

[0224] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0225]

[0226] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0227] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0228] The monofunctional monomers include TMCHA and CA, with a weight ratio of TMCHA to CA of 14:10, totaling 24 parts;

[0229] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0230] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0231] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0232] The thermosetting agent is Txiene BI 7981.

[0233] The nano-white paste comprises the following components by weight percentage:

[0234] HDDA 27.5%

[0235] Meililian 595 67.5%

[0236] BASF efka 4310 5%.

[0237] The additive is BYK 377.

[0238] The steps for preparing the above-mentioned nano-white paste are as follows:

[0239] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0240] The preparation of the above-mentioned curable inkjet includes the following steps:

[0241] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0242] Comparative Example 6

[0243] The difference between Comparative Example 6 and Example 1 is that the monofunctional monomers in Comparative Example 6 include ACMO and 4-HBA.

[0244] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0245]

[0246] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0247] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0248] The monofunctional monomers include ACMO and 4-HBA, with a weight ratio of ACMO to 4-HBA of 14:10, totaling 24 parts.

[0249] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0250] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0251] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0252] The thermosetting agent is Txiene BI 7981.

[0253] The nano-white paste comprises the following components by weight percentage:

[0254] HDDA 27.5%

[0255] Meililian 595 67.5%

[0256] BASF efka 4310 5%.

[0257] The additive is BYK 377.

[0258] The steps for preparing the above-mentioned nano-white paste are as follows:

[0259] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0260] The preparation of the above-mentioned curable inkjet includes the following steps:

[0261] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0262] Comparative Example 7

[0263] The difference between Comparative Example 7 and Example 1 is that the monofunctional monomers in Comparative Example 7 include TMCHA and 4-HBA.

[0264] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0265]

[0266] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0267] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0268] The monofunctional monomers include TMCHA and 4-HBA, with a weight ratio of TMCHA to 4-HBA of 14:10, totaling 24 parts;

[0269] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0270] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0271] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0272] The thermosetting agent is Txiene BI 7981.

[0273] The nano-white paste comprises the following components by weight percentage:

[0274] HDDA 27.5%

[0275] Meililian 595 67.5%

[0276] BASF efka 4310 5%.

[0277] The additive is BYK 377.

[0278] The steps for preparing the above-mentioned nano-white paste are as follows:

[0279] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0280] The preparation of the above-mentioned curable inkjet includes the following steps:

[0281] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0282] Comparative Example 8

[0283] The difference between Comparative Example 8 and Example 1 is that the amount of additive BYK 377 in Comparative Example 8 is 0.3 parts.

[0284] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0285]

[0286] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0287] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0288] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0289] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0290] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0291] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0292] The thermosetting agent is Txiene BI 7981.

[0293] The nano-white paste comprises the following components by weight percentage:

[0294] HDDA 27.5%

[0295] Meililian 595 67.5%

[0296] BASF efka 4310 5%.

[0297] The additive is BYK 377.

[0298] The steps for preparing the above-mentioned nano-white paste are as follows:

[0299] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0300] The preparation of the above-mentioned curable inkjet includes the following steps:

[0301] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0302] Comparative Example 9

[0303] The difference between Comparative Example 9 and Example 1 is that the amount of additive BYK 377 used in Comparative Example 9 is 0.05 parts.

[0304] A curing inkjet, wherein the raw material of the curing inkjet comprises the following components in parts by weight:

[0305]

[0306] The photoinitiators include TPO and 819, with a weight ratio of TPO to 819 of 6.5:1.5.

[0307] The weight ratio of monofunctional monomers, difunctional monomers, and trifunctional monomers in the UV monomers is 24:30:15.

[0308] The monofunctional monomers include ACMO and CA, with ACMO and CA in a weight ratio of 14:10, totaling 24 parts.

[0309] The bifunctional monomers include HDDA and NPG(PO)2DA, with a weight ratio of HDDA to NPG(PO)2DA of 10:20, totaling 30 parts.

[0310] The trifunctional monomer is TMPTA, with a weight of 15 parts.

[0311] The oligomer in question is BPA(EO). n DA, where n = 4, has a surface tension of 42.1 mN / m.

[0312] The thermosetting agent is Txiene BI 7981.

[0313] The nano-white paste comprises the following components by weight percentage:

[0314] HDDA 27.5%

[0315] Meililian 595 67.5%

[0316] BASF efka 4310 5%.

[0317] The additive is BYK 377.

[0318] The steps for preparing the above-mentioned nano-white paste are as follows:

[0319] According to the formula, the acrylate monomer and dispersant are mixed evenly, then titanium dioxide is added, and then the mixture is stirred at high speed to disperse evenly. Finally, the mixture is added to a sand mill and circulated and ground until D95≤700nm to obtain nano white paste.

[0320] The preparation of the above-mentioned curable inkjet includes the following steps:

[0321] Oligomers, UV monomers, photoinitiators, thermosetting agents, and additives were mixed and stirred at 1000 rpm for 1.5 hours under light-protected conditions to obtain a transparent oil. Finally, the previously obtained nano-white paste was mixed with it and stirred at 600 rpm for 1 hour. After filtration through a 1μm filter, the cured inkjet ink was obtained.

[0322] Performance testing:

[0323] The viscosity and surface tension of the UV inkjet inks obtained in Examples 1-4 and Comparative Examples 1-9 were tested. A Konica printhead (KM1024i, printhead temperature 50°C) and a 395nm wavelength LED-UV lamp were used to spray the ink onto the PCB solder resist layer to form ink blocks, which were then heat-cured (heat-curing temperature 150°C, time 1 hour). The adhesion and surface free energy of the ink blocks were tested, and the specific tests are as follows:

[0324] 1. Viscosity: GB / T 10247-2008 Viscosity Measurement Method.

[0325] 2. Adhesion: GB / T 9286-2021 Cross-cut adhesion test for paint and varnish films. (Hundred-cross test)

[0326] 3. Surface tension: GB / T 22237-2008 Determination of surface tension of surfactants. Platinum plate method.

[0327] 4. Surface free energy: DIN ISO 8296-2008 Plastics—Films and sheets—Determination of wetting tension. Dayn pen test.

[0328] Table 1 Test Results

[0329]

[0330]

[0331] As shown in Table 1, the inks of Examples 1-4 and Comparative Example 1 have high surface free energy after curing.

[0332] In the ink of Comparative Example 1, the trifunctional monomer TMPTA was replaced with GPTA. The surface tension of TMPTA is 36.6 mN / m, and that of GPTA is 36.0 mN / m. The surface free energy of the cured ink is 38, approximately equal to that of Example 1.

[0333] In Comparative Example 2, the ink used only HDDA as the bifunctional monomer, with a surface tension of 35.7 mN / m. Its photocuring speed was relatively fast, resulting in excessively smooth film formation during photocuring. The surface free energy of the cured ink was approximately 34, lower than that of Example 1. This is because the crosslinking properties of HDDA alone are relatively weak, while the combination of HDDA and NPG(PO)₂DA can form more crosslinked structures, resulting in a denser and more stable network structure after curing. Furthermore, the weaker crosslinking structure may lead to a decrease in the surface tension of the cured ink. Lower surface tension means better wettability of the ink surface, allowing the liquid to spread more easily on the surface, resulting in a smoother film.

[0334] In Comparative Example 3, the monofunctional monomer ACMO was replaced with DMMA. The surface tension of ACMO was 44.6 mN / m, while that of DMMA was 37.1 mN / m. The surface free energy of the cured ink was approximately 36, which was lower than that of Example 1.

[0335] In Comparative Example 4, the monofunctional monomer ACMO was replaced with TBCHA, which has a surface tension of 29.4 mN / m. The surface free energy of the cured ink was approximately 32, lower than that of Example 1.

[0336] In Comparative Example 5, the monofunctional monomer ACMO was replaced with TMCHA, which has a surface tension of 26.3 mN / m. The surface free energy of the cured ink was approximately 30, lower than that of Example 1.

[0337] In the ink of Comparative Example 6, the monofunctional monomer CA was replaced with 4-HBA. The surface tension of CA was 42.0 mN / m, while that of 4-HBA was 28.9 mN / m. The surface free energy of the cured ink was approximately 32, which was lower than that of Example 1.

[0338] In the ink of Comparative Example 7, the monofunctional monomer ACMO was replaced with TMCHA, and the monofunctional monomer CA was replaced with 4-HBA. The surface free energy of the cured ink was less than 28, which was lower than that of Example 1.

[0339] The ink in Comparative Example 8, using 0.3 parts of BYK 377, exhibited a stronger effect in reducing surface tension. The surface free energy of the cured ink was less than 28, lower than that of Example 1.

[0340] In Comparative Example 9, the ink using 0.05 parts of BYK 377 exhibited a strong effect in reducing surface tension, but even at only 0.05%, abnormal shrinkage occurred. It showed poor wetting properties, poor contact with the substrate, and poor adhesion. The surface free energy of the cured ink was 38, approximately equal to that of Example 1.

[0341] In summary, the beneficial effects of this invention are:

[0342] (1) Through experiments, this invention has found that the UV monomers ACMO, CA, and oligomers used have high surface tension, which significantly contributes to the surface tension of the inkjet mixture and the surface free energy after curing. When ACMO or CA is replaced with UV monomers with low surface tension (such as TBCHA, TMCHA, 4-HBA), or when ACMO and CA are replaced simultaneously, the surface tension of the system decreases (in liquids), and the surface free energy of the cured ink decreases significantly. The aforementioned test results of the replacement materials can guide the adjustment of the surface free energy after inkjet curing.

[0343] (2) Through experiments, this invention found that when the amount of additive (leveling agent) is 0.05 parts, inkjet printing on the substrate exhibits shrinkage. Compared with the amount of 0.1 parts in Example 1, it can be seen that the effect of 0.05 parts of additive in reducing surface tension is insufficient, resulting in shrinkage on the substrate. On the other hand, the effect of 0.3 parts of additive in reducing surface tension is too strong and affects adhesion.

[0344] The above are merely embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A cured inkjet, characterized by: The raw material of the solidified inkjet includes the following components by weight: a photoinitiator 7-10 parts; a UV monomer 50-75 parts; an oligomer 5-10 parts; a thermal curing agent 2-8 parts; The solidified inkjet also includes a color paste and an auxiliary agent, the color paste includes 20-25 parts of acrylic monomer, 65-70 parts of titanium white and 5-8 parts of dispersant; the auxiliary agent is 0.1 part of leveling agent; The UV monomer includes monofunctional monomer, bifunctional monomer and trifunctional monomer; The weight ratio of monofunctional monomer, bifunctional monomer and trifunctional monomer is 20-25:25-35:8-20; The oligomer includes at least one of ethoxylated bisphenol A diacrylate and ethoxylated bisphenol F diacrylate; The monofunctional monomer includes N-acryloyl morpholine and caprolactone acrylate; The bifunctional monomer includes 1,6-hexanediol diacrylate and 2-(propoxy) neopentyl glycol diacrylate; The trifunctional monomer includes trimethylolpropane triacrylate.

2. The cured inkjet according to claim 1, wherein: The photoinitiator includes at least one of 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide, 2,4,6-trimethylbenzoyl phenyl phosphonic acid ethyl ester, phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide, 2-isopropylthioxanthone, 4-dimethylamino-benzoic acid ethyl ester.

3. The cured inkjet according to claim 1, wherein: The thermal curing agent includes isocyanate.

4. The cured inkjet of claim 1, wherein: The acrylic monomer includes at least one of 1,6-hexanediol diacrylate, tripropyleneglycol diacrylate, neopentyl glycol diacrylate.

5. A method of preparing a cured inkjet ink according to any one of claims 1 to 4, characterized in that: The method includes the following steps: mixing the photoinitiator, the UV monomer, the oligomer and the thermal curing agent to obtain the solidified inkjet.

6. A PCB solder resist ink characterized by: The method includes the solidified inkjet of any one of claims 1-4.

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