KR101256456B1 - Uv curable resin composition and adhesives comprising thereof - Google Patents

Abstract

상기 식에서, R₁은 탄소수가 6내지 20인 방향족 또는 지방족 탄화수소이고, R₂는 독립적으로 탄소수가 2 내지 10인 지방족 탄화수소이고, R₃은 각각 독립적으로 탄소수가 2내지 10인 (메타)아크릴레이트기이고, l은 화학식 1의 반복단위로서, 15 내지 31이고, m은 16 내지 31의 자연수이고, n은 15 내지 30의 자연수이며, 이때 m은 n에 종속적으로 m=n+1이다. 또한 a, b는 독립적으로 5 내지 10 의 범위를 가지며, z는 자연수이다. The present invention relates to a solvent-free UV-curable coating composition and an adhesive using the same, which maintains transparency at high temperature, and has excellent optical properties of lifting / peeling resistance and warpage resistance. 40 to 80% by weight of the photopolymerized urethane acrylate oligomer according to formula (1); 5 to 55% by weight of a reactive monomer comprising at least one acrylate group, methacrylate group or vinyl group in the molecule; And a photoinitiator 1 to 10% by weight; solvent-free UV-curable coating composition comprising.
≪ Formula 1 >

Wherein R ₁ is an aromatic or aliphatic hydrocarbon having 6 to 20 carbon atoms, R ₂ is independently an aliphatic hydrocarbon having 2 to 10 carbon atoms, and R ₃ is each independently a (meth) acrylate having 2 to 10 carbon atoms. And l is a repeating unit of Formula 1, 15 to 31, m is a natural number of 16 to 31, n is a natural number of 15 to 30, where m is m = n + 1 depending on n. In addition, a and b independently have a range of 5 to 10, and z is a natural number.

Description

Solvent-free UV-curable coating composition and adhesive using same {UV CURABLE RESIN COMPOSITION AND ADHESIVES COMPRISING THEREOF}

The present invention relates to a solvent-free UV-curable coating composition and an adhesive using the same, and more particularly, to a solvent-free UV-curable coating composition having transparency at high temperatures, and having excellent optical properties of anti-peel / peel-off and anti-bending. It relates to the adhesive used.

Recently, with the advent of the information age, mobile communication terminals (mobile phones, PDA terminals, etc.), liquid crystal displays (LCDs), organic light emitting displays (OLEDs), and the like, form a large market. The main direction of the technical goal pursued with respect to such an image display apparatus is thinness, light weight, low power consumption, high resolution, high brightness, etc. are mentioned.

Particularly, in a small PDA or smart phone equipped with a touch panel as an input device, a transparent conductive thin film (e.g., polyethylene terephthalate film) is used as a substrate in terms of weight reduction and cracking prevention. A touch panel having a structure in which a transparent conductive film (for example, conductive PET) on which an ITO thin film) is formed is laminated on conductive glass by an adhesive is often used. Such a touch panel is fixed by being adhered by an adhesive tape or an adhesive sheet on the LCD module.

Such adhesive tapes or pressure-sensitive adhesive sheets are strongly required to have characteristics that do not cause lifting or peeling at the adhesive interface under harsh conditions such as high temperature and high humidity, but in reality, such a phenomenon occurs. Lifting or peeling may be due to moisture or residual monomer absorbed into the transparent substrate under severe conditions such as high temperature or high humidity of about 80 to 100 ° C., and outgassing may appear as a cause of foaming.

By bubbles generated from such a transparent plastic substrate or the like, lifting or peeling occurs at the adhesive interface between the substrate and the pressure-sensitive adhesive layer, which not only reduces the appearance but also significantly impairs the visibility. In addition, under such high temperature and high humidity conditions, it is necessary to uniformly relax the stress caused by the numerical change in the plastic substrate. However, when the stress relaxation property of the pressure-sensitive adhesive is poor, the residual stress becomes a residual monomer and in some cases, adverse effects such as discoloration and color failure.

Therefore, conventionally, as in the Republic of Korea Patent Publication No. 10-2006-123222, as the base polymer of the pressure-sensitive adhesive, various additives such as tackifiers to appropriately adjust the molecular weight of the acrylic polymer or to improve the adhesion to the transparent plastic substrate By adding or copolymerizing with a monomer component capable of improving the adhesiveness to prepare the base polymer of the adhesive, there is an attempt to prevent lifting or peeling even if bubbles are generated from the transparent plastic substrate or the like.

In order to polymerize when controlling the molecular weight of the acrylic polymer in order to improve the stress improvement and discoloration, bubbles in such high temperature and high humidity conditions, the solvent was inevitably applied such as ethyl acetate to increase the molecular weight. In addition, there may be a case where the average molecular weight is 500,000 g / mol or more and the low molecular weight is appropriately blended for improvement.

However, the above problems are actively improved in a relatively small display such as a mobile phone or a PDA terminal. However, in the case of a large display device such as a tablet PC or a digital view, a thin double-sided adhesive sheet is used. In order to maintain a stronger adhesive force while improving stress and discoloration, bubbles, and the like under high temperature and high humidity conditions, there are many difficulties.

In a large-scale display device, a thick film adhesive layer having a thickness of about 100 to 300 μm is required above all, but when using an acrylic polymer as in the prior art and a solvent type (or adhesive solution) adhesive, it is difficult to form a thick film. .

The technical problem to be solved by the present invention is to provide a solvent-free UV-curable coating composition and an adhesive using the same, which maintains transparency in high temperature and high humidity conditions, and has excellent optical properties of anti-peel / peel-off and warpage.

Solvent-free UV-curable coating composition according to the present invention for achieving the above technical problem, 40 to 80% by weight of the photopolymerizable urethane acrylate oligomer of the formula (1); 5 to 55% by weight of a reactive monomer comprising at least one acrylate group, methacrylate group or vinyl group in the molecule; And a photoinitiator 1 to 10% by weight; solvent-free UV-curable coating composition comprising.

≪ Formula 1 >

Wherein R ₁ is an aromatic or aliphatic hydrocarbon having 6 to 20 carbon atoms, R ₂ is independently an aliphatic hydrocarbon having 2 to 10 carbon atoms, and R ₃ is each independently a (meth) acrylate having 2 to 10 carbon atoms. And l is a repeating unit of Formula 1, 15 to 31, m is a natural number of 16 to 31, n is a natural number of 15 to 30, where m is m = n + 1 depending on n. In addition, a and b independently have a range of 5 to 10, and z is a natural number.

In addition, the ultraviolet curable coating composition of the present invention may be any component other than (A) a photopolymerizable urethane acrylate oligomer, (B) a reactive monomer comprising at least one acrylate group, methacrylate group or vinyl group in a molecule, and (C) a photoinitiator. And (D) other conventional additives such as silane monomers, stabilizers, photosensitizers, dispersants, or leveling agents may be further included.

Hereinafter, each component will be described in more detail.

(A) branched urethane acrylate oligomer

The photopolymerizable urethane acrylate oligomer used in the ultraviolet curable coating composition of the present invention is used in an amount of 40 to 80% by weight based on the ultraviolet curable coating composition. If it is less than 40% by weight, there is a problem that the adhesion strength is significantly lowered due to a decrease in cohesion of the adhesive layer, and when it exceeds 80% by weight, a work viscosity may be increased to cause workability problems.

The photopolymerized urethane acrylate oligomers used in the present invention are (i) 50 to 85% by weight of the main chain polyol copolymer, (ii) 1 to 10% by weight of the branched polyol copolymer (iii) 5 to 25% by weight of diisocyanate, (iv ) From 5 to 35% by weight of acrylate alcohol, from 0.01 to 1% by weight of (v) urethane reaction catalyst and from 0.01 to 1% by weight of (vi) polymerization inhibitor.

(i) main chain polyol copolymers

The main chain polyol copolymer (i) has a number average molecular weight of 1,000 to 10,000, and -CH ₂ COO- preferably comprises a repeating unit.

Preferred examples of the main chain polyol copolymer (i) include a polyester polyol, a polyether polyol, a polycarbonate polyol, a polycaprolactone polyol, and a ring-opening tetrahydro Tetrahydrofuran propyleneoxide ring opening copolymer, ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,5 -pentanediol), 1,6-hexanediol, 1,6-hexandiol, neopentyl glycol, 1,4-cyclohexane dimethanol and bisphenol-A ) Diols and the like.

The main chain polyol copolymer is more preferably a polycaprolactone polyol having a number average molecular weight of 1,000 to 3,000.

(ii) branched polyol copolymer

Preferred examples of the branched polyol copolymer may be branched in the polyurethane main chain direction. Bis-MPA (Dimethylolpropionic Acid) containing hydroxy groups in both directions, dimethylolbutanoic acid (DMBA) and ethylene oxide by applying the above structure Nonionic diol added.

(iii) diisocyanate

Preferred examples of the diisocyanate used in the present invention are 2,4-tolyenediisocyanate, 2,6-tolyenediisocyanate, 1,3-xylenediisocyanate, 1 , 4-xylene diisocyanate, 1,5-naphthalened diisocyanate, 1,6-hexanediisocyanate, isophoronediisocyanate (IPDI) and mixtures thereof There is this.

(iv) acrylate alcohol

The acrylate alcohol (iii) comprises at least one (meth) acrylate and a hydroxy group, preferred examples of which are 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2- Hydroxybutyl (meth) acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 4-hydroxybutyl acrylate, neo Pentyl glycol mono (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol penta (meth) Acrylate, trimethylolpropanediaryl, trimethylolpropanemonoaryl and mixtures thereof.

(v) urethane reaction catalyst

The urethane reaction catalyst (v) used in the present invention is a catalyst added in a small amount during the urethane reaction, and examples thereof include copper naphthenate, cobalt naphthenate, zinc naphthenate, and n-butyltinlaurate (n- butyltinlaurate), dibutyltindilaurate, tristhylamine, 2-methyltriethylenediamide and mixtures thereof.

(vi) polymerization inhibitor

Preferred examples of the polymerization inhibitor (vi) used in the present invention include hydroquione, hydroquinone monomethyl ether, para-benzoquinone, phenothiazine and mixtures thereof.

The branched urethane acrylate oligomer (A) can be synthesized from the respective components as follows:

First, diisocyanate (iii) is added to a round bottom flask with a stirrer. The urethane reaction catalyst (v) was added while stirring at 100 to 200 rpm (approximately 2/3 of the total catalyst (v) used), and the polyol copolymer (i) and the branched polyol copolymer (ii) were added to the reactor. Slowly inject into. The reaction temperature is about 70 to 80 ℃, the reaction time is about 2 to 3 hours. After completion of the reaction, the theoretical NCO concentration and the NCO concentration of the reactants are appropriately adjusted to obtain a urethane prepolymer, and the polymerization inhibitor (vi) and the acrylate alcohol (iv) are gradually added to react. After the addition of the reactant, the branched urethane acrylate oligomer can be obtained by maintaining the reaction temperature at 80 ° C. for 3 hours and reacting with an infrared spectrometer until the NCO peak of 2270 cm ⁻¹ disappears.

The photopolymerized urethane acrylate oligomer obtained by the above method has a number average molecular weight of 30,000 to 60,000 (gel permeation chromatography (GPC) measurement), the viscosity is 40,000 to 100,000cps (40 ℃, Brookfield Viscometer HB type (spindle) # 51)).

(B) reactive monomer

The reactive monomer (B) used in the present invention preferably uses a low molecular weight monomer having a number average molecular weight of 100 to 300 g / mol in order to match the working viscosity with the branched urethane acrylate oligomer (A) having a polymer structure. .

The reactive monomer has one or more acrylate groups, methacrylate groups or vinyl groups in the molecule, it is possible to use a monomer having 1 to 4, preferably 1 to 2 various functional groups. In particular, it is preferable to use a reactive monomer having a low glass shrinkage temperature while having a low glass transition temperature in the film state.

Preferred examples thereof include phenoxyethyl acrylate, phenoxyethylene glycol acrylate, phenoxy tetraethylene glycol acrylate, phenoxy hexaethylene glycol acrylate, isobornyl acrylate (IBOA), isobornyl methacrylate, 2-ethyl Hexyl acrylate (2-EHA), ethyl acrylate (EA), butyl acrylate (BA), lauryl acrylate (LA), N-vinylpyrrolidone (N-VP), N-vinyl caprolactam (N VC), acryloyl morpholine (ACMO), bisphenol ethoxylate diacrylate, ethoxylate phenol monoacrylate, polyethyleneglycol 400 diacrylate, tripropylene glycol diacrylate , Trimethyl propane triacrylate (TMPTA), polyethylene glycol diacrylate, ethylene oxide addition triethyl propane triacrylate (ethyleneoxide-addition trieth ylolpropantri acrylate), pentaerythritol tetraacrylate (PETA), 1,4-butanediol diacrylate, 1-6hexanediol diacrylate, ethoxylated pentaerythritol tetraacrylate, ethoxylate nonyl Phenol acrylate, 2-phenoxyethyl acrylate, ethoxylated bisphenol A diacrylate, alkoxylated nonylphenol acrylate, alkoxylated trifunctional acrylate ester , Metallic diacrylate, trifunctional acrylate ester, trifunctional methacrylate ester and mixtures thereof.

If necessary, in order to improve the adhesion with the surface to be coated, a monomer that exhibits an effect of increasing adhesion may be further used.

The reactive monomer is preferably used in the range of 5 to 55% by weight based on the total weight of the ultraviolet curable coating composition. If it is less than 5% by weight, it is difficult to dilute the high-viscosity oligomeric compound to a working viscosity of 3,000 to 10,000 cps (25 ° C). If it exceeds 55% by weight, the curing shrinkage of the film and the thermal stability at high temperatures The gel is formed off the viscosity is increased and the particles are large can lead to an unbalanced surface during coating, there is a problem in adhesion.

(C) photoinitiator

The photoinitiator (C) used in the present invention is added to maintain the fast curing rate of the resin itself. The photoinitiator may receive ultraviolet energy to form free radicals and attack a double bond in the resin to induce polymerization. Preferred examples thereof include commercially available Irgacure # 184 (hydroxycyclohexylketone) from Ciba Geigy, Igacure # 907 (2-methyl-1 [4- (methyl) Thio) phenyl] -2-morpholino-propan-1-one (2-methyl-1 [4- (methylthio) phenyl] -2-morpholino-propan-1-one)), Igacure # 500 (hydroxy Ketones and benzophenones, igacure # 651 (benzildimethyl-ketone), Darocure # 1173 (2-hydroxy-2-methyl-1-phenyl-propane -1-one (2-hydroxy-2-methyl-1-phenyl-propan-1-one), Darocure TPO (2,4,6-trimethylbenzoyl diphenylphosphine oxide (2,4,6-trimethylbenzoyl diphenylphosophinoxide)), Darocure CGI # 1800 (bisacylphosphineoxide), and CGI # 1700 (bisacylphosphine-oxide and hydroxy ketone).

(D) Other additives

In addition, the UV curable coating composition of the present invention may be used an effective amount of other amine additives, silane monomers, stabilizers, photosensitizers, dispersants or leveling agents as other additives, and preferably the total weight of the UV curable coating composition 1 to 5% by weight can be used as a standard.

Specifically, the ultraviolet curable coating composition of the present invention may include a silane monomer and a stabilizer to prevent the adhesion between the coating layer and the substrate is reduced. Silane-based monomers not only increase the adhesion between the coating layer and the glass but can also fundamentally reduce the water absorption of the resin composition. Representative examples of the silane monomers include vinyl trimethoxy silane, vinyl trimethoxy silane, biryl tri (methoxyethoxy) silane, gamma-methacryloxypropyltrimethoxy silane, and gamma-glycid from Chisso, Japan. Oxypropylmethoxy silane, gamma-aminopropyltriethoxy silane, gamma-mercaptopropyltrimethoxysilane, and the like, may be used at 1 to 5% by weight based on the total weight of the composition.

Stabilizers serve to improve thermal and oxidative stability and to improve the storage stability of coating compositions. Representative stabilizers include Irganox 1010, Iganox 1035, Iganox 1076, and Songwon Industries' TPP from Ciba. And mixtures thereof. The stabilizer is suitable to use about 0.1 to 5% by weight based on the total weight of the composition.

In addition, photosensitizers, dispersants, and leveling agents can be used as materials commonly used.

The process for preparing the solvent-free ultraviolet curable coating composition of the present invention is as follows:

A photopolymerizable urethane acrylate oligomer (A), a reactive monomer (B), a photoinitiator (C) and other additives (D) of Formula 1 are added to the reactor and dispersed impeller at a temperature of 15 to 50 ° C. and a humidity of 60% or less. The reaction is carried out using a stirring at a uniform speed of 1000rpm or more. If the reaction temperature is less than 15 ℃, the viscosity of the photopolymerized urethane acrylate oligomer (A) may increase the process problem, if the temperature exceeds 50 ℃ photo initiator (C) forms a radical to cure the reaction May cause When the reaction humidity exceeds 60%, the resulting resin composition may generate bubbles during the subsequent coating process, and a side reaction may occur in which an unreacted material reacts with moisture in the air. In addition, if the stirring speed is less than 1,000rpm may not be well blended.

The pressure-sensitive adhesive sheet having a coating layer having a thickness of 100 to 300 µm may be manufactured by first coating the substrate with the low-viscosity pressure-sensitive UV-curable coating composition of the present invention, followed by exposure (exposure to an UV lamp) to cure. In this case, a D-bulb having a light amount of 0.5 to 3 J / cm ² and a speed of 30 to 150 fpm can be used in the UV lamp in a nitrogen atmosphere.

Solvent-free UV-curable composition according to the present invention is easy to thick film coating of 100 to 300㎛ thickness on a number of substrates, even when cured to prepare an adhesive sheet has an excellent adhesive strength of 1kgf or more. In addition, heat resistance also has a significant advantage over the ultraviolet curable composition having a conventional linear structure.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example

Preparation Example 1: Preparation of Branch Radiated Urethane Acrylate Oligomer (A-1)

Into a 3-liter round bottom flask with a stirrer was charged 70.47 g (0.317 mole) of isophorone diisocyanate (IPDI) (Lyondell chemical company or Bayer) and 300 g of isobornyl acrylate (IBoA) Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After maintaining the reaction temperature at 60 ° C., 528.6 g (0.264 mole) of caprolactone polyol having a number average molecular weight of 2,000 g / mol and Perstorp's number average molecular weight of 1,000 g / mol and ethylene oxide were formed into branches. 13.22 g (0.0132 mol) of diols are charged to the reactor.

After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 0.55% was adjusted to between 0.1 and 0.5% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) (Eastman) g (0.66 mole) 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) was gradually added to the reaction.

After the completion of the addition, the reaction temperature was maintained at 80 ° C. for 2 hours, the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a branched urethane acrylate oligomer. The weight average molecular weight of the prepared oligomer is 53,000 g / mol (gel permeation chromatography (GPC)), and the viscosity is about 80,000 cps at 40 ° C.

Preparation Example 2 Preparation of Branch Radiated Urethane Acrylate Oligomer (A-2)

Into a 3-liter round bottom flask with a stirrer, 86.81 g (0.391 mole) of isophorone diisocyanate (IPDI) (manufactured by Lyondell Chemical Company or Bayer) and 300 g of isobornyl acrylate (IBoA) Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After the reaction temperature was maintained at 60 ° C., 488.4 g (0.326 mole) of polyester polyol having a number average molecular weight of 1,500 g / mol and the number average molecular weight of Perstorp company having a number average molecular weight of 1,500 g / mol were 1,000 g / mol. 16.38 g (0.0164 mol) of diol was added to the reactor.

After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 0.71% was adjusted between 0.1 and 0.7% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) (manufacturer: Eastman) and 107.5 g (0.81 mole) of 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) was gradually added to proceed with the reaction.

After the completion of the addition, the reaction temperature was maintained at 80 ° C. for 2 hours, the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a branched urethane acrylate oligomer. The weight average molecular weight of the prepared oligomer is 40,000 g / mol (gel permeation chromatography (GPC)), and the viscosity is about 55,000 cps at 40 ° C.

Preparation Example 3 Preparation of Photopolymerized Urethane Acrylate Oligomer (B-1)

Into a 3-liter round bottom flask with a stirrer, 64.83 g (0.292 mole) of isophorone diisocyanate (IPDI) (manufactured by Lyondell Chemical Company or Bayer) and 360 g of isobonyl acrylate (IBoA) Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After the reaction temperature was maintained at 60 ° C, 507.4 g (0.254 mole) of caprolactone polyol having a number average molecular weight of 2,000 g / mol Perstorp was added thereto. After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 0.55% was adjusted to between 0.1 and 0.5% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) (manufacturer: Eastman) and 67 g (0.51 mole) 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) was gradually added to proceed with the reaction.

After the end of the addition, the reaction temperature was maintained at 80 ° C. for 3 hours, the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a photopolymerized urethane acrylate oligomer. The weight average molecular weight of the prepared oligomer is 51,000 g / mol (gel permeation chromatography (GPC)), and the viscosity is about 130,000 cps at 40 ° C.

Preparation Example 4 Preparation of Photopolymerizable Urethane Acrylate Oligomer (B-2)

Into a 3-liter round bottom flask with a stirrer, 80.86 g (0.364 mole) of isophorone diisocyanate (IPDI) (manufactured by Lyondell Chemical Company or Bayer) and 360 g of isobornyl acrylate (IBoA) Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After maintaining the reaction temperature at 60 ° C, 474.6 g (0.316 mole) of polyester polyol having a number average molecular weight of 1,500 g / mol of Union Chemical Co., Ltd. was added thereto. After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 0.71% was adjusted between 0.1 and 0.7% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) (manufacturer: Eastman) and 83.6 g (0.63 mole) 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) was gradually added to proceed with the reaction.

After the end of the addition, the reaction temperature was maintained at 80 ° C. for 3 hours, the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a photopolymerized urethane acrylate oligomer. The weight average molecular weight of the prepared oligomer is 50,000 g / mol (gel permeation chromatography (GPC)) and the viscosity is about 100,000 cps at 40 ° C.

Preparation Example 5 Preparation of Photopolymerizable Urethane Acrylate Oligomer (C-1)

Into a 3-liter round bottom flask equipped with a stirrer, 82.03 g (0.369 mole) of isophorone diisocyanate (IPDI) (manufactured by Lyondell Chemical Company or Bayer) and 360 g of isobornyl acrylate (IBoA) Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After maintaining the reaction temperature at 60 ° C, 492.2 g (0.246 mole) of caprolactone polyol having a number average molecular weight of 2,000 g / mol Perstorp was added thereto. After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 1.81% was adjusted to between 1.5 and 1.8% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) (Eastman) and 65.0 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) of g (0.49 mole) was gradually added to proceed with the reaction.

After the completion of the addition, the reaction temperature was maintained at 80 ° C. for 1 hour, and the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a photopolymerized urethane acrylate oligomer. The weight average molecular weight of the prepared oligomer is 15,000 g / mol (gel permeation chromatography (GPC)), and the viscosity is about 4,500 cps at 40 ° C.

Preparation Example 6 Preparation of Photopolymerizable Urethane Acrylate Oligomer (C-2)

Into a 3-liter round bottom flask with agitator, 104.89 g (0.472 mole) of isophorone diisocyanate (IPDI) (manufactured by Lyondell Chemical Company or Bayer) and 360 g of isobornyl acrylate (IBoA) Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After maintaining the reaction temperature at 60 ° C, 472.1 g (0.236 mole) of caprolactone polyol having a number average molecular weight of 2,000 g / mol of Perstorp was added thereto. After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 3.41% was adjusted to between 2.9 and 3.4% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) manufactured by Eastman and 62.4. g (0.47 mole) 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) was gradually added to the reaction.

After the completion of the addition, the reaction temperature was maintained at 80 ° C. for 2 hours, and the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a photopolymerized urethane acrylate oligomer. The weight average molecular weight of the prepared oligomer is 9,000 g / mol (gel permeation chromatography (GPC)) and the viscosity is about 2,500 cps at 40 ° C.

Preparation Example 7 Preparation of Photopolymerized Urethane Acrylate Oligomer (D)

Into a 3-liter round bottom flask with a stirrer was charged 64.83 g (0.292 mole) of isophorone diisocyanate (IPDI) manufactured by Lydelldell Chemical Company or Bayer and 200 g of isobornyl acrylate (IBoA). Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After the reaction temperature was maintained at 60 ° C., ethylene oxide was added to the main chain direction of 235.7 g (0.127 mole) of caprolactone polyol having a number average molecular weight of 2,000 g / mol, and 2,000 g / mol of polyol. 235.7 g (0.127 mol) of the prepared polyisomer polyol is sequentially added to the reactor.

After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 0.55% was adjusted to between 0.1 and 0.5% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) manufactured by Eastman and 227 g. (1.72 mole) 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) was gradually added to proceed with the reaction.

After the completion of the addition, the reaction temperature was maintained at 80 ° C. for 2 hours, and the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a photopolymerized urethane acrylate oligomer. The number average molecular weight of the prepared oligomer was 37,000 g / mol (gel permeation chromatography (GPC)), and the viscosity was 14,500 cps at 40 degreeC.

Preparation Example 8 Preparation of Photopolymerizable Urethane Acrylate Oligomer (E)

Into a 3-liter round bottom flask with a stirrer was charged 64.83 g (0.292 mole) of isophorone diisocyanate (IPDI) manufactured by Lydelldell Chemical Company or Bayer and 200 g of isobornyl acrylate (IBoA). Then, 0.3 g of dibutyl tin dilaurate (dibutyltindilaurate) (manufactured by Songwon Industry) is added.

After the reaction temperature was maintained at 60 ° C., 507.4 g (0.254 mole) of a Polycer type PTMG2000 polyol having a number average molecular weight of 2,000 g / mol of Basf was added to the reactor. After completion of the dosing, the NCO concentration of the reactants having a theoretical NCO concentration of 0.55% was adjusted to between 0.1 and 0.5% to obtain a urethane prepolymer, and 0.03 g of hydroquinone monomethyl ether (HQMME) manufactured by Eastman and 227 g. (1.72 mole) 2-hydroxypropyl acrylate (2-HPA) (manufactured by Nippon shokubai) was gradually added to proceed with the reaction.

After the completion of the addition, the reaction temperature was maintained at 80 ° C. for 2 hours, and the infrared spectroscopy confirmed that the NCO peak of 2270 cm ⁻¹ disappeared, and the reaction was terminated to obtain a photopolymerized urethane acrylate oligomer. The weight average molecular weight of the prepared oligomer was 59,000 g / mol (gel permeation chromatography (GPC)), and the viscosity was 210,000 cps at 40 degreeC.

Examples 1 to 2: Preparation of UV Curable Coating Composition

The branched-urethane urethane acrylate oligomers prepared in Preparation Examples 1 to 2 were each blended in the composition of components as shown in Table 1 to obtain an ultraviolet curable coating composition.

Comparative Examples 1 to 6: Preparation of UV Curable Coating Composition

Using the urethane acrylate oligomers prepared in Preparation Examples 3 to 8, respectively, they were formulated into a composition of components as shown in Table 1 to obtain an ultraviolet curable coating composition.

division ingredient Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Oligomer
(A) Production Example 1 65 Production Example 2 65 Production Example 3 65 Production Example 4 65 Production Example 5 65 Production Example 6 65 Production Example 7 65 Production Example 8 65 Reactive monomer
(B) 2-ethylhexyl acrylate
(2-EHA) 19 19 19 19 19 19 19 19 Ethoxyethoxyethyl acrylate (ED-021) 12 12 12 12 12 12 12 12 Isobonylacrylate
(IBoA) One One One One One One One One Photoinitiator
(C) Darocure # 184 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 additive
(D) Iganox # 1076 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

Test Example: Evaluation of Physical Properties of UV Curable Coating Composition

In order to examine the mechanical properties and adhesive properties of the UV-curable coating composition prepared in Examples and Comparative Examples, the results of the viscosity, curing conditions, and adhesive strength with various optical substrates after curing are shown in the following [Table 2]. It was.

(1) Viscosity

The viscosity of the composition is measured in the range of 50-90% torque using spindle 31 using a Brookfield Viscometer (Brookfield DV III +) according to ASTM D-2196.

(2) adhesive strength with interposition after curing

Apply the composition prepared in Examples and Comparative Examples on a 20 × 20 cm size PET film, fix it with a bar coater at about 150 micrometers, push it, put it in a fixed mold into which nitrogen is injected (nitrogen flow rate 40lpm), and fusion. Using a 600W 9mm D-bulb of the company (model: DRS10 / 12-QN), the amount of light at a speed of 50fpm 2.0J / cm 2 was irradiated and cured to produce a film. After laminating the film of the cured composition with a light release release liner, cut to 25 mm in width, stored in an oven at 40 ° C. and a relative humidity of 50% or less for 2 hours, after lamination on the substrate, Instron 4443 UTM The adhesive force between the PET films is measured by pulling the film at a speed of 300 mm / min at an angle of 180 ° using.

(3) Evaluation method of durability

     Apply the composition prepared in Examples and Comparative Examples on a 10 × 10 cm size PET film (188 microns thick), fix it with a bar coater at about 150 microns, push it, and put it in a fixed mold in which nitrogen is injected (nitrogen flow rate 40lpm). ), Using a 600W 9mm D-bulb of Fusion Yarn (model: DRS10 / 12-QN) to irradiate and cure the amount of light at a speed of 50fpm 2.0J / cm 2 to produce a film.

After laminating the film of the cured composition with a light release release liner, cut it to 50x50 mm and store it in an oven at 40 ° C., a relative humidity of 50% or less for 2 hours, and then lamination to glass at 80 ° C., and 60 The weather resistance test is performed for 500 hours at the conditions of ℃ and 95% RH. After this weather resistance test, durability is evaluated by visual observation as follows. [No defect] means that bubbles and floating are not observed as appearance defects at the adhesive interface, and [defect] means that some bubbles are generated and observed locally.

(4) Heat resistance evaluation method

Apply the composition prepared in Examples and Comparative Examples on a 10 × 10 cm size PET film (188 microns thick), fix it with a bar coater at about 150 microns, push it, and put it in a fixed mold in which nitrogen is injected (nitrogen flow rate 40lpm). ), Using a 600W 9mm D-bulb of Fusion Yarn (model: DRS10 / 12-QN) to irradiate and cure the amount of light at a speed of 50fpm 2.0J / cm 2 to produce a film.

After laminating the film of the cured composition with a light peeling release liner, it was cut to 50x50 mm and stored in an oven at 40 ° C. and a relative humidity of 50% or less for 2 hours, after lamination on glass for 500 hours at 100 ° C. in a high temperature condition. The heat resistance yellowing test is performed and the degree of color change [according to ASTM 1925] is measured using a Minolta 3700d.

Example Comparative example Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Viscosity (cps) 5,300 3,500 8,500 6,500 1,500 1,200 2,800 23,000 Oligomer Type Caprolactone Branch Radiation Polyester Branch Radiation Caprolactone oligomer Polyester oligomer Caprolactone oligomer Caprolactone oligomer Caprolactone and Polycer Oligomers Polymer oligomer [Polyol]: [isocyanate] molar ratio 1: 1.2 1: 1.2 1: 1.2 1: 1.2 1: 1.5 1: 2 1: 1.2 1: 1.2

Adhesive force (gf) Adhesion to glass (gf) 2,300 2,050 1,500 1,800 400 190 1,100 400 Adhesive force to PMMA sheet (gf) 2,600 2,300 1,150 1,500 550 550 1,000 550 Adhesive force with PC sheet (gf) 2,500 3,200 1,400 1,000 500 400 1,500 1,500
durability
(500 hr left) 80 ℃ No defect No defect No defect No defect No defect No defect No defect No defect 60 ℃ and 95% RH No defect No defect flaw flaw flaw flaw flaw No defect Yellowing degree (100 ℃ * 500hr) <1 or less 5.5 <1 or less 5.2 2.5 2.7 4.8 2.5

As can be seen in Table 2, in Examples 1 to 2 according to the present invention, the same diisocyanate and polyol as in Example 1 to 2 are applied, and the molar ratio (diisocyanate / By maintaining the polyol) from 1.05 to 1.25, it can be seen that excellent adhesion of 1 kgf or more on various substrates. In addition, when the molar ratio is not maintained, as in Comparative Examples 3 to 4, it was found that the adhesive strength is remarkably decreased, and the branched radial structure shows a significantly better result than the linear structure even in heat resistance.

The difference between the caprolactone polyol and the polyester polyol in Examples 1 to 2 or Comparative Examples 1 to 2, although the ester (CH2COO) group had a great influence on the adhesion, the color change in the 100 ° C heat evaluation, the caprolactone structure Remarkably good results can be confirmed.

In addition, as can be seen in Comparative Examples 5 to 6, even if the molar ratio (diisocyanate / polyol) is maintained from 1.05 to 1.25, preferably the adhesive strength is reduced to the glass and PMMA sheet when the structure is not the same as that of Formula 1, And it can be seen that the fall significantly in durability.

Claims (12)

40 to 80% by weight of the photopolymerized urethane acrylate oligomer described in Formula 1 below; 5 to 55% by weight of a reactive monomer comprising at least one acrylate group, methacrylate group or vinyl group in the molecule; And a photoinitiator 1 to 10% by weight; solvent-free UV-curable coating composition comprising.
&Lt; Formula 1 >

Wherein R ₁ is an aromatic or aliphatic hydrocarbon having 6 to 20 carbon atoms, R ₂ is independently an aliphatic hydrocarbon having 2 to 10 carbon atoms, and R ₃ is each independently a (meth) acrylate having 2 to 10 carbon atoms. And l is a repeating unit of Formula 1, 15 to 31, m is a natural number of 16 to 31, n is a natural number of 15 to 30, where m is m = n + 1 depending on n. In addition, a and b independently have a range of 5 to 10, and z is a natural number. The method of claim 1, wherein z is
Solvent-free UV-curable coating composition, characterized in that the natural water of 15 to 20. The method of claim 2, wherein the photopolymerizable urethane acrylate oligomer,
50 to 85 weight percent of backbone polyol copolymer; 1 to 10% by weight of the branched polyol copolymer; 5 to 25 weight percent diisocyanate; 5 to 35 weight percent of acrylate alcohol; 0.01 to 1 wt% urethane reaction catalyst; And 0.01 to 1% by weight of a polymerization inhibitor. A solvent-free ultraviolet curable coating composition, characterized in that it is prepared from a composition comprising a. The method of claim 3, wherein the main chain polyol copolymer,
A solvent-free ultraviolet curable coating composition having a number average molecular weight of 1,000 to 10,000, wherein -CH ₂ COO- comprises a repeating unit. The method of claim 3,
Solvent-free UV-curable coating composition, characterized in that the molar ratio of the main chain polyol copolymer and the branched polyol copolymer is 1.05 ~ 1.23. The method of claim 3, wherein the main chain polyol copolymer,
Polyester polyols, polyether polyols, polycarbonate polyols, polycaprolactone polyols, ring-opening tetrahydrofuran propyleneoxide ring opening copolymers, Ethylene glycol, propylene glycol, 1,4-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 6-hexandiol), neopentyl glycol (neopentyl glycol), 1,4-cyclohexane dimethanol (1,4-cyclohexane dimethanol) and any one selected from the group consisting of diols of the bisphenol-A (bisphenol-A) type or Solvent-free UV curable coating composition, characterized in that the mixture of two or more. The method of claim 3, wherein the main chain polyol copolymer,
A solvent-free ultraviolet curable coating composition characterized in that the polycaprolactone polyol having a number average molecular weight of 1,000 to 3,000. The method according to claim 3, wherein the branched polyol copolymer,
It contains a hydroxyl group in both directions, Bis-MPA (Dimethylolpropionic Acid), DMBA (Dimethylolbutanoic Acid), Bis-MPA (Dimethylolpropionic Acid), DMBA (Dimethylolbutanoic Acid) is characterized in that any one of nonionic diol Solvent-free ultraviolet curable coating composition. The method of claim 3, wherein the diisocyanate is
2,4-tolylenediisocyanate, 2,6-tolylenediisocyanate, 1,3-xylenediisocyanate, 1,4-xylenediisocyanate, 1,5- Naphthalene diisocyanate (1,5-naphthalenediisocyanate), 1,6-hexanediisocyanate (1,6-hexanediisocyanate), isophoronediisocyanate (IPDI), any one or a mixture of two or more selected from the group consisting of Solvent-free ultraviolet curable coating composition. The method of claim 3, wherein the acrylate alcohol,
One or more (meth) acrylates and hydroxy groups, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy Hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 4-hydroxybutyl acrylate, neopentylglycol mono (meth) acrylate, 4-hydroxy Oxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol penta (meth) acrylate, trimethylolpropanediaryl, trimethylol Solvent-free UV-curable coating composition, characterized in that any one or a mixture of two or more selected from the group consisting of propane monoaryl. An adhesive comprising the solvent-free ultraviolet curable coating composition according to any one of claims 1 to 10. An adhesive sheet produced by coating the solvent-free ultraviolet curable coating composition according to any one of claims 1 to 10 on one surface of a substrate, followed by curing.