KR101158696B1 - Printing ink composite for etching resist comprising polyurethane polymer - Google Patents

Abstract

The present invention relates to a dendritic polyurethane polymer produced by polymerization of diols containing trifunctional isocyanates and carboxylic acid side chains in a 1: 2 to 1: 5 molar ratio, a preparation method thereof, and an ink composition for etching resist printing. The ink composition for printing an etching resist of the present invention includes the polyurethane polymer, the low boiling point solvent, the high boiling point solvent, and an additive including a humectant and an air bubble remover, and the etching resist is left with volatile solvents removed from the ink composition. It is formed by the solid component formed. Such an etching resist is excellent in adhesiveness to a metal and peeling resistance to an etching solution, but has a characteristic of being peeled off by a weak alkali or an aqueous stripping solution.

Description

Ink composition for printing an etching resist comprising a polyurethane-based polymer {Printing ink composite for etching resist comprising polyurethane polymer}

The present invention relates to an ink composition for etching resist printing comprising a polyurethane polymer of dendritic structure produced by polymerizing diol containing trifunctional isocyanate and carboxylic acid side chain. Specifically, the present invention synthesizes a polyurethane-based polymer having a dendritic structure, and the polyurethane-based polymer is mixed with a low boiling point solvent, a high boiling point solvent, and an additive to etch excellent in peeling properties with respect to the etching solution and the peeling property by the removing solution. The present invention relates to a technique for providing a resist composition.

The development of various electronic devices that have changed our lives conveniently today is due to the development of various patterning technologies, including the manufacturing technology of semiconductors embedded in electronic devices. The development of patterning technology is in line with the development of semiconductor technology, and various types of patterning technologies have been developed.

The development direction of patterning technology is divided into the development of highly fine patterning technology that can pattern the line width in nanometers as in the field of DRAM development, and the development of patterning technology that has a large line width but low process cost. The former is implemented by a method of transferring and patterning a pattern patterned on a photomask to a resist on a wafer by using an exposure apparatus attached to expensive equipment such as a stepper or a scanner, and dry etching capable of anisotropic etching. Since the latter has a larger scale of the pattern than the former, the latter is implemented through wet etching having an isotropic etching characteristic or an inkjet method or a gravure printing method using no separate mask. One of the fields in which the wet etching patterning technology is required is an antenna manufacturing technology of an RFID tag.

In recent years, the frequency of use of RFID tags attached to humans or objects to be managed and transmitting information in a non-contact state is increasing, and their application fields are also expanding. The RFID tag has an IC chip for storing data and enables information exchange between objects by transmitting and receiving radio waves. For example, an RFID tag is embedded in a commuter pass of a transportation institution and used to manage a ride section or a fare, or perform a task such as managing a person's access, a product's inventory, or a logistics management in a company.

The RFID tag includes a certain type of antenna for transmitting and receiving electromagnetic waves. The manufacturing method of an RFID tag antenna is mainly performed by wet etching with etching liquid. The wet etching may be performed by coating a photoresist on a substrate on which a metal film is formed, exposing and developing the photoresist using a mask to form an etching resist in a predetermined pattern, and etching the lower metal film with an etchant. However, in the etching resist formation method using the photoresist, expensive equipment, such as a spin coater or an exposure machine, is inevitably used, and the process cost is complicated because the steps of the process are complicated.

Printing technology is a technique that can replace the etching resist formation method using a photo resist having the above problems. Printing technology can form a pattern directly on a metal film without a mask or exposure equipment, so the process cost is low and productivity is excellent. This printing technique is highly dependent on the physical properties of the ink forming the pattern, the accuracy and productivity of the pattern. In general, the higher the content of the active ingredient in the ink, the higher the ratio of the active ingredient to the same amount of droplets, so the characteristics of the formed pattern are excellent. However, as the solid content of the ink increases, the viscosity of the ink increases, so that it is difficult to print stably and the storage stability also decreases. In addition, the peeling resistance to the etching solution of the etching resist pattern formed through printing and the peeling efficiency by the peeling solution also largely depend on the composition of the ink. Therefore, the market demand for the development of the etching resist composition having a high content of the active ingredient, excellent storage stability, and excellent properties for the etching solution and the stripping solution is increasing.

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink composition for etching resist printing comprising a polyurethane-based polymer having excellent peeling resistance with respect to etching liquid and peeling characteristic with a peeling liquid.

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In order to solve the above problems, the present invention,
Polyurethane type polymer | macromolecule produced by superposing | polymerizing the diol which contains 65-85 weight% of trifunctional isocyanate and carboxylic acid in a side chain of 1: 2-1: 5 molar ratio;
A high boiling point solvent having a boiling point of 2 to 6% by weight of 100 to 150 ° C;
Low boiling point solvent having a boiling point of 8 to 24% by weight of 60 to 80 ℃; And
Provided is an ink composition for etching resist printing comprising an additive comprising 1 to 6% by weight of a wetting agent and an antifoaming agent.

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According to one embodiment of the present invention, the etching resist composition of the present invention may further comprise 1 to 6% by weight of the curing agent relative to the total composition.

According to another embodiment of the present invention, the present invention may use at least one selected from the group consisting of oxazoline, aziridine and carbodiimide as a curing agent.

According to another embodiment of the present invention, the present invention may use at least one selected from the group consisting of N-methylpyrrolidone, dimethyl formamide and dimethyl sulfoxide as a high boiling point solvent.

According to another embodiment of the present invention, the present invention may use at least one selected from the group consisting of tetrahydrofuran, acetone and methyl ethyl ketone as a low boiling point solvent.

According to another embodiment of the present invention, the present invention may use a polyether modified dimethylpolysiloxane as a wetting agent.

Polyurethane-based polymer material included in the etching resist composition of the present invention has a dendritic structure (dendritic) structure has a low molecular weight and has a large molecular weight characteristics can exhibit excellent mechanical properties. Moreover, the etching resist composition containing such a polyurethane-type polymer is excellent in peeling resistance with respect to a metal etching liquid, and the peeling characteristic by peeling liquid.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings based on embodiments. The examples presented are exemplary and are not intended to limit the scope of the invention.

 The composition for etching resists of the present invention includes a polyurethane-based polymer produced by polymerizing diols containing 65 to 85% by weight of trifunctional isocyanate and carboxylic acid in a side chain of 1: 2 to 1: 5 molar ratio. The polyurethane-based polymer is produced by polymerizing a difunctional isocyanate or a diol including a polyisocyanate and a carboxylic acid side chain. The trifunctional isocyanate and polyisocyanate include aromatic aliphatic and cycloaliphatic polyisocyanates. Based on cost solubility and the properties imparted to the product polyurethane, aromatic polyisocyanates are generally preferred. Representative polyisocyanates include, for example, m-phenylene diisocyanate, 2,4- and / or 2,6-toluene diisocyanate (TDI), various isomers of diphenylmethane diisocyanate (MDI), hexamethylene-1, 6-diisocyanate, tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate, hexahydrotoluene diisocyanate, hydrogenated MDI (H12 MDI), naphthylene-1,5-diisocyanate, methoxy Phenyl-2,4-diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenyl diisocyanate, 3,3'-dimethyldiphenylmethane-4, 4'-diisocyanate, 4,4 ', 4 "-triphenylmethane tri-isocyanate, polymethylene polyphenylisocyanate, hydrogenated polymethylene polyphenylisocyanate, toluene-2,4,6-triisocyanate, and 4,4' Dimethyldiphenylmethane-2,2 ', 5,5'-tetraisocyanate Preferred polyisocyanates include HDI and derivatives of HDI, such as biuret-modified “liquid” HDI products and polymeric HDI, as well as biuret or laurate modifications of MDI, TDI, IPDI. The polyurethane-based polymer is a dendritic polymer having a dendritic structure, which is also called a branched structure, and a dendritic polymer means a polymer compound having a regular branching shape like a tree branch. The polyurethane-based polymer of the present invention is characterized by low molecular weight, high molecular weight, and excellent mechanical properties due to such structural characteristics, and also polymers having various ranges of viscosities can be synthesized according to the synthetic conditions of the polymer even in adjusting the viscosity. Controlling the viscosity of polymers is characterized by printing characteristics using polymers, especially gravure (gra vure) is related to the characteristic of filling polymers tightly in the uneven portion during printing, and consequently affecting the precision of the pattern formed by printing, and controlling the mechanical properties of the polymer. It is related to robustness and also affects the precision of the pattern.

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The polyurethane-based polymer according to the present invention contains a large number of carboxyl groups. Diols containing carboxylic acid as a side chain include dimethylol propanoic acid, or dimethylol butanoic acid. The carboxyl group affects the etching characteristics of the etching resist composition comprising the polyurethane-based polymer. First, the carboxyl group increases the adhesion of the etching resist to the metal film. Metals contain free electrons on their surface, and carboxyl groups play a role in delocalizing electrons to bonds between carbon and oxygen through resonance structures and enhancing interactions with free electrons. This adhesion property to the metal film prevents the etching solution from penetrating into the lower portion of the etching resist during etching of the metal film, resulting in pattern defects. Second, the carboxyl group improves the peeling resistance to the etching solution. In general, an etching solution such as FeCl ₃ may be used to etch the metal film, and the carboxyl groups form a complex with Fe in the etching solution, thereby preventing the polymer from dissolving in the etching solution. Third, the carboxyl group improves the peeling characteristics by the stripping solution. Carboxyl groups are acidic groups, which increase the solubility in aqueous solutions, especially in weak alkaline solutions.

In the polyurethane-based polymer of the present invention, difunctional isocyanate containing trifunctional isocyanate or polyisocyanate and carboxylic acid side chain is preferably polymerized in a 1: 2 to 1: 5 molar ratio. When there are too many hexamethylene diisocyanate trimers, since the highly reactive isocyanate group remains in the side chain terminal of the synthesized polyurethane type polymer, storage property becomes low. When there are too many diols containing carboxylic acid as a side chain, the diols containing unreacted carboxylic acid as a side chain exist and defect may arise at the time of printing.

The polyurethane-based polymer of the present invention may be polymerized through the following process. First, dimethylol propanoic acid is dissolved in a mixed solution of N-methylpyrrolidone and tetra hydrofuran to prepare a first solution. Subsequently, the hexamethylene diisocyanate trimer is dissolved in tetrahydrofuran to prepare a second solution. Subsequently, the first solution and the second solution are mixed and polymerized at a temperature of 60 to 80 ° C. In this case, an infrared spectrometer may be used to confirm the termination of the polymerization. When the polymerization proceeds dimethylol profile If the attack of the oxygen atom is an isocyanate group of hexamethylene diisocyanate trimer of the alcohol group of the acid group remains unreacted isocyanate since polyurethane structure is produced characteristic peaks at 2270㎝ ^-1 in the infrared spectrum is observed do. If the presence of unreacted isocyanate is confirmed by infrared spectroscopy, optionally a small amount of catalyst such as DBTDL (dibutyl tin dilaulate) can be added, and then the temperature is increased to proceed with the reaction to complete the polymerization.

The etching resist composition of the present invention can form a pattern through gravure printing. Gravure printing is a technique in which ink is applied to a plate on which a pattern of irregularities is formed, and the ink of the remaining portions except for the concave portion is scraped off and printed on the substrate. In gravure printing, the printing quality is determined by the viscosity of the ink filled in the concave portion, the degree of volatilization of the solvent, and the like.

The etching resist composition of the present invention is 65 to 85% by weight of the polyurethane-based polymer, 2 to 6% by weight of high boiling point solvent, 8 to 24% by weight of low boiling point solvent, 1 to 6% by weight of the additive composition It includes. At this time, the high boiling point solvent is a solvent having a boiling point of 100 to 150 ℃, may be at least one selected from the group consisting of N-methylpyrrolidone, dimethyl formamide and dimethyl sulfoxide. The low boiling point solvent is a solvent having a boiling point of 60 to 80 ° C., and may be at least one selected from the group consisting of tetrahydrofuran, acetone and methylethyl ketone. The additive may include a wetting agent and a defoamer, and a polyether modified dimethylpolysiloxane-based BYK-345, BYK-346, or BYK-348, etc., sold by BYK, may be used as the wetting agent, and BYK-011 may be used as an antifoaming agent. Can be.

High boiling solvents serve to dissolve dimethylol propanoic acid. If the high boiling point solvent is contained in less than 2% by weight dimethylol propanoic acid is not dissolved well, the transfer capacity is reduced during printing, and if contained in more than 6% by weight is difficult to dry after pattern formation, the productivity is low. Low-boiling solvents are highly volatile solvents that help to effectively fill ink in recesses during gravure printing. When the low boiling point solvent is included in less than 8% by weight, the ink viscosity is too high, it is difficult to fill the ink, and when included in excess of 24% by weight, the viscosity of the ink is too low, there is a problem that the ink flows down.

Among the components of the additive, the humectant may impart hydrophilic properties to the etching resist composition to improve affinity with the metal film, thereby improving transfer ability during printing, and the bubble remover serves to prevent pattern defects caused by bubble generation.

The etching resist composition of the present invention may further comprise a curing agent. The curing agent serves to crosslink the polyurethane-based polymer to improve mechanical properties of the pattern formed by printing. The curing agent may be at least one selected from the group consisting of oxazoline, aziridine, and carbodiimide, and is preferably included in an amount of 1 to 6% by weight based on the total composition. When there is too much addition amount of a hardening | curing agent, the peeling characteristic with respect to a peeling liquid will fall.

Hereinafter, the present invention will be described in more detail using examples and comparative examples of the present invention.

Example 1

Dimethylol propanoic acid was added to a reactor containing a mixture of N-methylpyrrolidone and tetrahydrofuran, and the temperature was raised to 60 ° C. to confirm the dissolution of DMPA. Subsequently, a tetrahydrofuran solution in which hexamethylene diisocyanate trimer was dissolved was added to the reactor, and the reaction was performed at 70 ° C. for 4 hours. Subsequently, it was confirmed that the characteristic peak of 2270cm ^-1 disappeared through the infrared spectroscopy. At this time, the molar ratio of hexamethylene diisocyanate trimer and dimethylol propanoic acid was 1: 3.

The polyurethane-based polymer produced through the polymerization reaction was mixed with N-methylpyrrolidone, tetra hydrofuran, oxazoline, and an additive to prepare an etching resist composition. The etching resist composition was comprised of 75% by weight of polyurethane based polymer, 4% by weight of N-methylpyrrolidone, 15% by weight of hydrofuran, 3% by weight of oxazoline and 3% by weight of additives. . The additive was used by mixing 1: 1 with BYK-346 and BYK-011.

Using the etching resist composition, patterns of 1 cm × 1 cm and 10 cm × 10 cm were formed on the aluminum film by gravure printing.

Example 2

The etching resist composition was etched in the same manner as in Example 1 except that the composition was 75% by weight of the polyurethane-based polymer, 5% by weight of N-methylpyrrolidone, 16% by weight of hydrofuran, and 4% by weight of the additive. A resist composition was prepared, and patterns of 1 cm × 1 cm and 10 cm × 10 cm were formed on the aluminum film by gravure printing.

Comparative Example 1

The etching resist composition was prepared in the same manner as in Example 1 except that the synthesis of the polyurethane-based polymer was carried out in a 1: 1 molar ratio of hexamethylene diisocyanate trimer and dimethylol propanoic acid. And a pattern of 10 cm x 10 cm was formed by gravure printing.

Comparative Example 2

The etching resist composition was prepared in the same manner as in Example 1 except that the synthesis of the polyurethane-based polymer proceeded with a 1: 6 molar ratio of hexamethylene diisocyanate trimer and dimethylol propanoic acid. And a pattern of 10 cm x 10 cm was formed by gravure printing.

Experimental Example

The following tests were performed on the patterns formed according to Examples and Comparative Examples, and the results are shown in Table 1 below.

1. Metal adhesion test (cross-cut test)

The pattern of 1 cm x 1 cm formed according to the Example and the comparative example was cut | disconnected with a razor blade at 1 mm intervals, the cellophane tape was affixed on the pattern, and the tape was removed in the 180 degree direction. The shape of the remaining pattern was observed, and if there was a dropped pattern, it was judged to be defective or not good.

2. Peeling resistance test for etching solution

Embodiment a pattern of 1㎝ × 1㎝ observed natneunji allowed to stand for 3 minutes in a solution of FeCl ₃ 50 ℃ to the peeling of the etching resist pattern is formed up by the etching solution in accordance with the examples and comparative examples. If peeling was found, it was judged to be defective, and if not found to be good.

3. Pin hole test

The pattern of 10 cm x 10 cm formed in accordance with the Examples and Comparative Examples was observed with an electron microscope to observe the number of pinholes having a diameter of 10 µm or more. If the observed pinhole number was 10 or more, it was considered bad, and if it was less than 10, it was judged good.

4. Peeling characteristic test by peeling liquid

The patterns of 10 cm × 10 cm formed according to Examples and Comparative Examples were treated with 50 ^° C. of 5% NaOH aqueous solution for 1 minute. If the pattern remained after the treatment, it was judged to be defective, and if it was not left, it was good.

Metal adhesion Peeling Resistance to Etching Solution Pinhole count By stripping solution
Peeling properties Example 1 Good Good Normal (2) Good Example 2 Good Good Normal (3) Good Comparative Example 1 Bad Bad Good (7) Bad Comparative Example 2 Good Good Bad (28) Good

Examples 1 and 2 showed good results in all of the metal adhesion, the peeling resistance to the etching solution, the number of pinholes and the peeling property test by the peeling solution. In Comparative Example 1, the metal adhesion, the peeling resistance to the etching solution and the peeling property by the peeling solution were poor, and the infrared spectroscopy analysis showed that the unreacted isocyanate groups were present in the polyurethane-based polymer synthesis process. there was. In Comparative Example 2, the number of pinholes was 28, indicating a poor result.

Claims (9)

delete delete delete Polyurethane type polymer | macromolecule produced by superposing | polymerizing the diol which contains 65-85 weight% of trifunctional isocyanate and carboxylic acid in a side chain of 1: 2-1: 5 molar ratio;
A high boiling point solvent having a boiling point of 2 to 6% by weight of 100 to 150 ° C;
Low boiling point solvent having a boiling point of 8 to 24% by weight of 60 to 80 ℃; And
An ink composition for printing an etching resist comprising an additive comprising 1 to 6% by weight of a wetting agent and a defoamer. The method of claim 4, wherein
The high boiling point solvent is at least one selected from the group consisting of N-methylpyrrolidone, dimethyl formamide and dimethyl sulfoxide, the ink composition for printing an etching resist. The method of claim 4, wherein
The low boiling point solvent is at least one selected from the group consisting of tetrahydrofuran, acetone and methyl ethyl ketone ink resist printing ink composition. The method of claim 4, wherein
The wetting agent is an ink composition for etching resist printing, characterized in that the polyether modified dimethylpolysiloxane. The method of claim 4, wherein
Ink composition for etching resist printing further comprising 1 to 6% by weight of the curing agent relative to the total composition. The method of claim 8,
The curing agent is an ink composition for etching resist printing, characterized in that at least one selected from the group consisting of oxazoline, aziridine and carbodiimide.