KR101418026B1 - Thermosetting ink composition - Google Patents

Abstract

The present invention relates to a thermosetting ink composition. More particularly, the present invention relates to a thermosetting ink composition including a binder resin with a hydroxyl group, a curing agent expressed by chemical formula 1, a multifunctional monomer having an ethylenically non-saturated double bond and a solvent, and may be cured at low temperatures, thereby being applicable to a flexible display using a polymer resin film as a substrate to form a pattern without degradation of the film.

Description

[0001] THERMOSETTING INK COMPOSITION [0002]

The present invention relates to a thermosetting ink composition which can be cured at a lower temperature.

2. Description of the Related Art Fine patterns applied to an image display device such as a liquid crystal display device, a plasma display device, and the like and a semiconductor circuit device have been formed by a photolithography method using a photoresist.

The photolithography method has an advantage that a desired pattern can be precisely obtained. However, in order to maximize the effect of the photoresist, expensive exposing equipment and a high resolution mask are required, and a large amount of photoresist is consumed in the process, It is inefficient. In addition, since it is a multi-step process such as exposure, post-exposure baking, development, development, baking, etching, cleaning, etc., the process takes a long time and the process is repeated many times.

In recent years, printing methods such as offset, inversion offset, roll-to-roll, and dispensing nozzles have been proposed as a method for replacing the photolithography method.

The resin composition is applied to the substrate by the above methods and is heated and cured to form a predetermined pattern. Such a heat curing process is usually carried out at a high temperature of about 230 캜.

On the other hand, as the display field gradually moves to flexible displays, a flexible substrate is required, and conventionally used glass substrates are replaced by polymeric resin films such as polyimide and polyethylene terephthalate films. In the case of the high temperature process, There is no problem in forming the polymeric resin film. However, the polymeric resin film has problems such as shrinkage or deterioration due to heat at a high temperature.

Accordingly, there is a demand for a resin composition which can be cured even at a low temperature such that the polymer resin film used for a flexible substrate or the like does not deteriorate.

Korean Patent Publication No. 2008-68286 discloses a thermosetting overcoat resin composition.

Korean Patent Publication No. 2008-68286

An object of the present invention is to provide an ink composition which can be cured at a lower temperature.

1. A resin composition comprising a binder resin having a hydroxy group, a curing agent, a polyfunctional monomer having an ethylenically unsaturated double bond and a solvent,

Wherein the curing agent is a compound represented by the following Formula 1:

[Chemical Formula 1]

,

또는

이고;(Wherein, R ₁ is an alkyl group having 1 to 5 carbon atoms,

,

or

ego;

R ₂ is an alkylene group having 1 to 10 carbon atoms;

R ₃ and R ₄ are independently of each other an alkyl group having 1 to 5 carbon atoms;

and n is an integer of 1 to 3).

2. The ink composition according to 1 above, wherein the curing agent is contained in an amount of 0.1 to 5% by weight based on the total weight of the composition.

3. The ink composition according to item 1 above, wherein the binder resin is a novolak resin.

4. The ink composition according to 1 above, wherein the binder resin is contained in an amount of 10 to 20% by weight based on the total weight of the composition.

5. A pattern formed from the composition of any one of claims 1-4.

6. The pattern as set forth in 5 above, wherein the pattern is a color pattern for a color filter, a black matrix pattern, a black column spacer pattern, a thin film transistor pattern, an electrode pattern for an image display device, or a partition wall pattern.

The ink composition of the present invention can be cured even at a lower temperature. Therefore, it can be applied to a flexible display using a polymeric resin film as a substrate, so that a pattern can be formed without deteriorating the film.

The present invention relates to a flexible display using a polymer resin film as a substrate, which can be cured even at a lower temperature by including a binder resin having a hydroxyl group, a curing agent represented by the formula (1), a polyfunctional monomer having an ethylenically unsaturated double bond, To a thermosetting ink composition capable of forming a pattern without deteriorating the film.

Hereinafter, the present invention will be described in detail.

≪ Thermosetting ink composition >

The thermosetting ink composition of the present invention comprises a binder resin having a hydroxyl group, a curing agent, a polyfunctional monomer having an ethylenically unsaturated double bond, and a solvent.

Binder resin

The binder resin according to the present invention is not particularly limited as long as it has a hydroxyl group and can be reacted with a curing agent to be described later, and resins commonly used in the art can be used. For example, it may be a novolak resin.

The novolak resin is a novolak type phenolic resin obtained by copolymerizing at least one phenolic compound and an aldehyde compound.

The phenolic compound is not particularly limited and includes, for example, phenols, cresols such as p-cresol, m-cresol and o-cresol, 3,5-xylenol, 2,5- - xylenol, 3,4-xylenol and the like; 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol, 2,6-dimethylphenol, 3,4- Dimethylphenols such as phenol and 3,5-dimethylphenol; phenols such as 2,3,4-trimethylphenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol and 2,4,5- Butylphenol such as trimethylphenol, 2-t-butylphenol, 3-t-butylphenol and 4-t-butylphenol, Chlorophenols such as phenol, etc .; chlorinated phenols such as m-methoxyphenol, p-methoxyphenol, o-methoxyphenol, 2,3-dimethoxyphenol, 2,5-dimethoxyphenol and 3,5- Phenoxyphenols; p-butoxyphenol; ethylphenol, m-ethylphenol, p-ethylphenol, 2,3-diethylphenol, 2,5-diethylphenol, 3,5-diethylphenol, 2,3,5-triethylphenol, 3 , Ethylphenols such as 4,5-triethylphenol, resorcinols such as resorcinol, 2-methyl resorcinol, 4-methyl resorcinol and 5-methyl resorcinol, p-isopropylphenol, Naphthols such as naphthol and? -Naphthol; and methylene bisphenol, methylene bis p-cresol, catechol, and 4-methylresorcin. These may be used alone or in combination of two or more.

The aldehyde compound is not particularly limited, and examples thereof include formaldehyde, paraformaldehyde, acetaldehyde, propylaldehyde, benzaldehyde, phenylaldehyde,? -Phenylpropylaldehyde,? -Hydroxybenzaldehyde, Hydroxybenzaldehyde, p-hydroxybenzaldehyde, glutaraldehyde, glyoxal, o-methylbenzaldehyde, p-methylbenzaldehyde and the like. These may be used alone or in combination of two or more.

The binder resin may be contained in an amount of 10 to 20% by weight in 100% by weight of the total ink composition. In this content range, the role of the pattern support and the pattern transfer rate can be improved to improve yield and process efficiency

Hardener

The curing agent according to the present invention is represented by the following Formula 1:

[Chemical Formula 1]

,

또는

이고;(Wherein, R ₁ is an alkyl group having 1 to 5 carbon atoms,

,

or

ego;

R ₂ is an alkylene group having 1 to 10 carbon atoms;

R ₃ and R ₄ are independently of each other an alkyl group having 1 to 5 carbon atoms;

and n is an integer of 1 to 3).

When an isocyanate group (-NCO) reacts with a hydroxyl group (-OH), when a curing agent having an isocyanate group is used in an ink composition, the reaction is very excellent and the reaction with a binder resin having a hydroxyl group even at a room temperature before the heat- There is a problem that it is difficult to uniformly coat and form a fine pattern.

Therefore, conventionally, a high temperature curing process at about 230 캜 was performed using an ink composition including a polymerizable compound, a thermal initiator, a silane additive and the like to form a pattern.

However, the present invention includes a curing agent in which the carbon atoms of the isocyanate group are not double-bonded to the nitrogen atom and are protected by other substituents.

When the curing agent according to the present invention does not react with a hydroxyl group at room temperature and applies heat at a predetermined temperature or higher (about 120 ° C), the protecting group is dissociated to react with the binder resin to activate the isocyanate group And they are cured by crosslinking.

That is, the ink composition of the present invention can be cured even at a low temperature of about 120 캜 by including the curing agent, and thus can be used for pattern formation applied to a flexible display or the like.

The curing agent may be included in an amount of 0.1 to 5% by weight based on 100% by weight of the ink composition. When the content is less than 0.1% by weight, the degree of crosslinking is insignificant and the degree of curing of the pattern may be deteriorated. If the content is more than 5% by weight, the storage stability of the composition may be deteriorated.

Ethylenic  Having an unsaturated double bond Multifunctional  Monomer

The multifunctional monomer having an ethylenically unsaturated double bond is a component for enhancing the strength of the pattern and may include a monofunctional monomer. Specific examples include monofunctional compounds such as nonylphenylcarbitol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexylcarbitol acrylate, 2-hydroxyethyl acrylate and N- Monomer; (Meth) acrylates such as 1,6-hexanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, triethylene glycol di Bifunctional monomers such as 3-methylpentanediol di (meth) acrylate; Trifunctional monomers such as trimethylolpropane tri (meth) acrylate and pentaerythritol tri (meth) acrylate; Tetrafunctional monomers such as pentaerythritol tetra (meth) acrylate; Pentafunctional monomers such as dipentaerythritol penta (meth) acrylate; And hexafunctional monomers such as dipentaerythritol hexa (meth) acrylate. These may be used alone or in combination of two or more.

The multifunctional monomer having an ethylenically unsaturated double bond may be contained in an amount of 1 to 10% by weight based on 100% by weight of the ink composition. Good pattern strength can be obtained in this content range.

menstruum

The solvent is preferably an ethylene glycol monoalkyl ether such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, or ethylene glycol monobutyl ether in consideration of solubility, dispersibility of the colorant, coating property, and the like; Diethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether and diethylene glycol dibutyl ether; Ethylene glycol alkyl ether acetates such as methyl cellosolve acetate and ethyl cellosolve acetate; Alkylene glycol alkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methoxybutyl acetate, and methoxypentyl acetate; Aromatic hydrocarbons such as benzene, toluene and xylene; Ketones such as methyl ethyl ketone, acetone, methyl amyl ketone, methyl isobutyl ketone, and cyclohexanone; Alcohols such as ethanol, methanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol and glycerin; and cyclic esters such as? -butyrolactone. These may be used alone or in combination of two or more.

The solvent may be contained in an amount of 75 to 90% by weight based on 100% by weight of the ink composition. When the content is less than 75% by weight, the solid content is increased and the viscosity is increased to deteriorate the coating property. When the content is more than 90% by weight, the solid content is excessively decreased to cause difficulties in the coating phase and a large amount of solvent It is not good in terms of process.

coloring agent

The ink composition of the present invention may further comprise colorants known in the art.

The coloring agent may be an organic coloring agent such as pigment, dye, synthetic or natural coloring matter, or an inorganic coloring agent such as metal oxide, metal complex salt, barium sulfate (extender pigment).

As the colorant, compounds classified as pigments and dyes in the Color Index (The Society of Dyers and Colourists) may be used, and these may be used alone or in combination of two or more.

Specific examples of the pigment include C.I. Pigment yellow 1, 12, 13, 14, 15, 16, 17, 20, 24, 31, 53, 83, 86, 93, 94, 109, 110, 117, 125, 128, 137, 138, 139, 147, 148, 150, 153, 154, 166, 173, 180, 185; C.I. Pigment orange No. 13, 31, 36, 38, 40, 42, 43, 51, 55, 59, 61, 64, 65, 71, 73; C.I. Pigment red 9, 97, 105, 122, 123, 144, 149, 166, 168, 176, 177, 180, 192, 215, 216, 224, 242, 254, 255, 264, 265; C.I. Pigment Blue 15, 15: 3, 15: 4, 15: 6, 60; C.I. Pigment purple No. 1, No. 14, No. 19, No. 23, No. 29, No. 32, No. 33, No. 36, No. 37, No. 38; C.I. Pigment Green 7, 10, 15, 25, 36, 47; C.I. Pigment brown No. 23, No. 25, No. 28; C.I. Pigment black No. 1, No. 7, carbon black, and the like.

Specific examples of the dye include C.I. Solvent yellow 2, 14, 16, 33, 34, 44, 56, 82, 93, 94, 98, 116, 135; C.I. Solvent Orange No. 1, No. 3, No. 7, No. 63; C.I. Solvent Red 1, 2, 3, 8, 18, 23, 24, 27, 35, 43, 45, 48, 49, 91: 1, 119, 135 No. 140, No. 196, No. 197; C.I. Solvent Purple No. 8, No. 9, No. 13, No. 26, No. 28, No. 31, No. 59; C.I. Solvent Blue No. 4, No. 5, No. 25, No. 35, No. 36, No. 38, No. 70; C.I. Solvent Green No. 3, No. 5, No. 7 and the like.

The content of the coloring agent may be adjusted according to the required color characteristics, and may be included in an amount of 5 to 20% by weight based on 100% by weight of the ink composition.

additive

The ink composition containing the above-mentioned components may further contain at least one additive such as an adhesion promoter, an antioxidant, a dispersant, and a surfactant.

<Pattern>

The present invention also provides a pattern made from the ink composition.

The pattern of the present invention may be a color pattern for a color filter, a black matrix pattern, a black column spacer pattern, a thin film transistor pattern, an electrode pattern for an image display device, or a barrier rib pattern.

The pattern can be formed by applying the ink composition on a substrate and thermosetting it.

The coating method is not particularly limited and may be carried out by, for example, offset printing, reverse offset printing, screen printing, gravure printing, dispensing, spraying, casting, bar coating, die coating and spin coating.

The coated film is cured to form a pattern.

Since the ink composition of the present invention can be cured at a lower temperature, it is possible to form a pattern under more relaxed conditions. For example, the pattern can be formed by curing at a temperature of 120 to 150 DEG C for 10 to 30 minutes, but is not limited thereto.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to be illustrative of the present invention and are not intended to limit the scope of the appended claims. It will be apparent to those skilled in the art that such variations and modifications are within the scope of the appended claims.

Example  One

30% by weight of pigment carbon black and 3% by weight of polyester dispersant (Diperbyk-2010, BYK) were mixed to prepare a mill base.

Next, 12% by weight of a binder resin having a weight average molecular weight (Mw) of 5,000 (containing m-cresol and p-cresol in a weight ratio of 6: 4 and polymerizing, formaldehyde copolymerization) , 8 wt% of dipentaerythritol hexaacrylate (Toagoes), 1.5 wt% of BI-7963 (baxenden) as a curing agent, 0.2 wt% of a surfactant (TF-1535, DIC) % Of propylene glycol monomethyl acetate.

Then, the above mixture was stirred for 3 hours to prepare an ink composition.

Example  2-3, Comparative Example  1- 3

The binder resin, the kind and content of the curing agent were used in the same manner as in Example 1, as shown in Table 1 below.

division Binder resin Hardener Kinds content
(weight%) Kinds content
(weight%) Example 1 A 12 BI-7963 1.5 Example 2 A 12 BI-7963 0.05 Example 3 A 12 BI-7963 5.5 Example 4 A 12 BI-7983 2.0 Comparative Example 1 B 12 BI-7983 0.5 Comparative Example 2 A 12 BI-7641 0.5 Comparative Example 3 A 12 SI-100L
(Samsin Chemistry) 0.5 A: The binder resin used in Example 1
B: Copolymer of methacrylic acid and benzyl methacrylate having a weight average molecular weight (MW) of 8,000

Experimental Example

(1) Evaluation of pattern adhesion

The ink compositions of Examples and Comparative Examples were coated on a glass substrate using a spin coater and cured by heating at 120 DEG C for 30 minutes. The cured coating film was subjected to a tape peeling test using JIS K5400, and the degree of the total of 100 pieces of the grid-cut was examined. The results are shown in the drawing.

(2) Chemical resistance evaluation

The coating film prepared in Experimental Example 1 was immersed in a 1% potassium hydroxide aqueous solution (alkali-resistant), MA-So2 (Dongwoo Fine Chemical Co., Ltd.) (acid resistance) and SAM-19 And the chemical resistance was evaluated by the change of adhesion before and after immersion.

<Evaluation Criteria>

?: 90 to 100 presence of plaids (good)

DELTA: Existence of lattice pattern of not less than 80 and not more than 90 (normal)

X: Less than 80 grid patterns (defective)

(3) Evaluation of storage stability

The initial viscosity of the ink compositions of Examples and Comparative Examples was measured and stored at 5 占 폚 for one month, respectively, and the viscosity was measured to observe the viscosity change. The viscosity was measured with a Brookfield viscometer (Brookfield Viscometer DVI +, manufactured by BROOKFIELD) at 25 ° C. The measurement results are shown in Table 1 below.

◎: Viscosity change 3% or less

?: Viscosity change from more than 3% to less than 5%

?: Change in viscosity exceeding 5% to 10%

×: Viscosity change exceeding 10%

division Adhesiveness Chemical resistance Storage stability Alkali resistance Acid resistance My peeling liquor Example 1 ○ ○ ○ ○ ◎ Example 2 △ ○ △ ○ ◎ Example 3 ○ ○ ○ ○ △ Example 4 ○ ○ ○ ○ ○ Comparative Example 1 △ △ X △ ○ Comparative Example 2 △ △ X △ ○ Comparative Example 3 X △ X △ ○

Referring to Table 2, a pattern was formed through a low-temperature curing process at 120 ° C. However, the patterns prepared from the ink compositions of Examples 1 to 4 exhibited excellent adhesion to a substrate and excellent chemical resistance.

However, the patterns prepared with the compositions of Comparative Examples 1 to 3 had poor adhesion to the substrate and poor chemical resistance.

Claims (6)

Curable thermosetting ink composition comprising a novolak resin, a curing agent represented by the following formula (1), a polyfunctional monomer having an ethylenically unsaturated double bond, and a solvent:
[Chemical Formula 1]

(Wherein, R ₁ is an alkyl group having 1 to 5 carbon atoms,

,

or

ego;
R ₂ is an alkylene group having 1 to 10 carbon atoms;
R ₃ and R ₄ are independently of each other an alkyl group having 1 to 5 carbon atoms;
and n is an integer of 1 to 3).
The low temperature curable thermosetting ink composition according to claim 1, wherein the curing agent is contained in an amount of 0.1 to 5% by weight based on the total weight of the composition.
delete The low temperature curable thermosetting ink composition according to claim 1, wherein the novolak resin is contained in an amount of 10 to 20% by weight based on the total weight of the composition.
A pattern formed from the composition of any one of claims 1, 2 and 4.
The pattern according to claim 5, wherein the pattern is a color pattern for a color filter, a black matrix pattern, a black column spacer pattern, a thin film transistor pattern, an electrode pattern for an image display device, or a barrier rib pattern.