Compound for a curable composition

Abstract

The present application relates to a curable composition, a cured product and uses of the curable composition and the cured product. By comprising the curable compound having a certain structure, the present application can provide a curable composition which can increase cohesiveness of the cured product without increasing viscosity of the composition before curing, also minimize the increase of the elastic modulus, and also minimize the ratio of a nonreactive oligomer with an effect of improving the interfacial adhesion. The curable composition can be applied to a variety of optical applications and can be usefully used, for example, for bonding various optical functional members in a display device, for example, for directly bonding a touch panel and a display panel.

Claims

1. A compound represented by the Formula 1 below: ##STR00006## wherein, in the Formula 1, A is a core comprising a polyalkylene oxide unit and derived from polyalkylene polyol, B is a chain connected to said core, and is represented by Formula 2 below, n is a number of 0 or more, m is a number of 1 or more, n+m is a number of 3 or more, and K is -L-R, wherein said L is a linker and R is a polymerizable functional group that is an acryloyl group, an acryloyloxy group, a methacryloyl group or a methacryloyloxy group, ##STR00007## wherein, in Formula 2, A.sub.1 is an alkylene group, Q.sub.1 is an alicyclic or aromatic divalent residue, L.sub.1 to L.sub.3 are each independently a linker, R is a polymerizable functional group or a residue of Formula 3 below, wherein the polymerizable functional group is an acryloyl group, an acryloyloxy group, a methacryloyl group or a methacryloyloxy group, and n is any number, ##STR00008## wherein, in Formula 3, Q.sub.2 is an alicyclic or aromatic divalent residue, L.sub.4 is a linker, A is the same as A in Formula 1, K is the same as K in Formula 1, and p is a number of 2 or more, wherein L.sub.3 in Formula 2 and L in the -L-R is represented by Formula D or E below: ##STR00009## wherein, in Formulas D and E, each of X is independently a single bond, an alkylene group, an oxyalkylene group or an alkyleneoxy group, and R.sub.1 and R.sub.2 are each independently a hydrogen atom or an alkyl group.

2. The compound according to claim 1, wherein the polyalkylene oxide unit is a polyethylene oxide unit or a polypropylene oxide unit.

3. The compound according to claim 1, wherein the polyalkylene polyol has a weight average molecular weight in a range of 1000 to 10,000.

4. The compound according to claim 1, wherein L.sub.1, L.sub.2 and L.sub.4 in Formulas 2 and 3 are each independently an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group or an alkynylene group, or a linker represented by Formula D or E below: ##STR00010## wherein, in Formulas D and E, each of X is independently a single bond, an alkylene group, an oxyalkylene group or an alkyleneoxy group, and R.sub.1 and R.sub.2 are each independently a hydrogen atom or an alkyl group.

5. The compound according to claim 1, wherein the structure of -L.sub.1-Q.sub.1-L.sub.2- or the structure of -L.sub.3-Q.sub.2-L.sub.4- in Formulas 2 and 3 is a structure derived from a diisocyanate compound.

6. The compound according to claim 5, wherein the diisocyanate compound is tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoboron diisocyanate, tetramethylxylene diisocyanate or naphthalene diisocyanate.

7. The compound according to claim 1, wherein [O-A.sub.1].sub.n in Formula 2 is a structure derived from polyalkylene glycol.

8. The compound according to claim 1, wherein in Formula 1, n is 0, m is a number of 3 or more, and in Formula 2: ##STR00011## R is the polymerizable functional group.

9. The compound according to claim 1, wherein in Formula 1, n is 1 or more, m is 1 or more, and in Formula 2: ##STR00012## R is the residue of Formula 3 ##STR00013##

10. A curable composition comprising the compound of Formula 1 of claim 1.

11. A display panel comprising a display body and an optically functional material which are bonded with the curable composition of claim 10.

12. A display device comprising a touch panel and a display panel which are bonded with the curable composition of claim 10.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIGS. 1 and 2 are schematic diagrams of an exemplary display device of the present application.

(2) FIG. 3 is a schematic diagram of a display device related to the background art.

(3) FIG. 4 is the IR spectrum of the compound prepared in Example.

MODE FOR INVENTION

(4) Hereinafter, the present application will be described in more detail through Examples according to the present application, but the scope of the present application is not limited to Examples to be described below.

(5) 1. IR Spectrum Measurement Method

(6) The measurement conditions of the IR spectrum applied in this specification are as follows. Upon measuring, the air condition was set as the base line.

(7) <Measurement Conditions>

(8) Measuring instrument: Agilent Cary 660 FTIR Spectrometer

(9) ATR: PIKE Technologies 025-2018 Miracle Znse perf crystal plate

(10) Measured wavelength: 400 to 4000 nm

(11) Measuring temperature: 25 C.

(12) 2. Evaluation of Molecular Weight

(13) The weight average molecular weight (Mn) was measured using GPC under the following conditions, and the measurement results were converted into standard polystyrene of Agilent system for preparing the calibration curve.

(14) <Measurement Conditions>

(15) Measuring instrument: Agilent GPC (Agilent 1200 series, U.S.)

(16) Column: Two PL Mixed B connected

(17) Column temperature: 40 C.

(18) Eluent: THF (tetrahydrofuran)

(19) Flow rate: 1.0 mL/min

(20) Concentration: 1 mg/mL (100 L injection)

(21) 3. Measurement of Storage Elastic Modulus

(22) After curing the curable compositions obtained in Examples and Comparative Examples and cutting the cured products into a size of 8 mm in diameter and 1 mm in thickness to prepare circular samples, the elastic modulus of the samples was measured using an ARES (Advanced Rheometrics Expansion System) by a frequency sweep mode at 25 C. and a frequency of 1 Hz.

(23) 4. Tensile Strength Measurement

(24) The tensile strength was measured using a UTM (Zwick/Roell Z005) by ASTM D412 method while stretching a specimen having a thickness of 1 mm at a speed of 50 mm/min.

(25) 5. Peeling Force Measurement

(26) After curing the curable compositions obtained in Examples and Comparative Examples and cutting the cured products to a size of 15 mm in width, 100 mm in length and 250 m in thickness to prepare specimens, the peeling force of these specimens was measured using a TA-XT2plus [Tension] at 25 C. with a peeling angle of 180 and a peeling speed of 300 mm/min.

(27) Specifically, in a polarizing plate comprising a TAC (triacetyl cellulose) film as a protective film, after applying the curable composition on the TAC film to a thickness of about 250 m and covering the prepared PET film having a width of 15 mm and a length of about 100 mm (thickness: 100 m) thereon, the curable composition was cured to measure the peeling force against the polarizing plate, while peeling the PET film.

EXAMPLE 1

Preparation of the Compound of Formula 1

(28) A compound, in which in Formula 1 above, n is 0, m is 3, B is a chain of Formula 2 and the chain of Formula 2 is represented by Formula F below, was synthesized by the following method. PPG (polypropylene glycol) (weight average molecular weight: 6000) and a catalyst (dibutyltin dilaurate) were injected in a weight ratio of 78:0.002 (PPG:catalyst) into a reactor equipped with a heating device, a condenser and a thermometer for refluxing reflux nitrogen gas and facilitating temperature control, and the temperature was gradually increased and maintained to 55 C. Thereafter, AOI (2-isocyanatoethyl acrylate) was slowly added in drops for 30 minutes to be finally in a weight ratio (PPG:catalyst:AOI) of 78:0.002:1.8 and further stirred at the same temperature for 1 hour to synthesize a first compound. The reaction time was determined through an IR spectrum, and the reaction was carried out until the NCO peak identified at 2270 cm.sup.1 in the IR spectrum before reaction completely disappeared.

(29) Subsequently, the first compound was added in drops to the reactor where IPDI (isophorone diisocyanate), MEHQ (4-methoxyphenol) and a catalyst (dibutyltin dilaurate) were present, in a weight ratio of 2.9:0.17:0.003 (IPDI:MEHQ:catalyst) at 50 C. for 30 minutes, and reacted by further stirring the mixture at the same temperature for 30 minutes. The reaction time and the input of the first compound were adjusted until the area of the NCO peak identified at 2270 cm.sup.1 in the IR spectrum decreased to 50%. Polypropylene triol (GP-4000, KPX, weight average molecular weight: 4000) was further added thereto and reacted with further stirring the mixture at 65 C. for 4 hours to prepare the desired compound. Here, the input of polypropylene triol and the reaction time were controlled to such an extent that the NCO peak at 2270 cm.sup.1 completely disappeared through the IR. The weight average molecular weight (Mw) of the desired compound thus synthesized was about 26,000.

(30) ##STR00005##

(31) In Formula F, R is an acryloyloxyethyl group.

EXAMPLE 2

Curable Composition

(32) The compound prepared in Example 1, a mono-functional reactive oligomer, a nonreactive oligomer, a monomer for dilution and an initiator were mixed in a weight ratio of 10:3:51:36:0.32 (reactive oligomer; compound of Example 1: nonreactive oligomer:monomer for dilution:initiator) to prepare a curable composition.

(33) As the mono-functional reactive oligomer, a polyurethane oligomer derived from polypropylene glycol and having one acryloyloxy group and a molecular weight of about 17,000 was used, and as the nonreactive oligomer, a polyurethane oligomer derived from polypropylene glycol and having a molecular weight of about 17,000 was used, as the monomer for dilution, isobornyl acrylate was used, and as the initiator, a compound known as Irgacure 819 was used.

COMPARATIVE EXAMPLE 1

Preparation of Curable Composition

(34) The mono-functional reactive oligomer and the nonreactive oligomer, the monomer for dilution, and the initiator, of Example 2 were mixed in a weight ratio of 10:54:36:0.32 (reactive oligomer:nonreactive oligomer:monomer for dilution:initiator) to prepare a curable composition.

COMPARATIVE EXAMPLE 2

Preparation of Curable Composition

(35) The mono-functional reactive oligomer of Example 2, a bi-functional reactive oligomer, the nonreactive oligomer of Example 2, the monomer for dilution of Example 2, and the initiator of Example 2 were mixed in a weight ratio of 10:3:51:36:0.32 (reactive oligomer (mono-functional):reactive oligomer (bi-functional):nonreactive oligomer:monomer for dilution:initiator) to prepare a curable composition.

(36) Here, as the bi-functional reactive oligomer, a polyurethane oligomer derived from polypropylene glycol and having two acryloyloxy groups and a molecular weight of about 17,000 was used.

COMPARATIVE EXAMPLE 3

Preparation of Curable Composition

(37) The mono-functional reactive oligomer and the nonreactive oligomer, the monomer for dilution and the initiator, of Example 2, and MFA (DIPENTAERYTHRITOL HEXAACRYLATE) were mixed in a weight ratio of 10:51:36:0.32:3 (reactive oligomer:nonreactive oligomer:monomer for dilution:initiator:MFA) to prepare a curable composition.

(38) The results of evaluating the measured physical properties of the curable compositions are summarized and described in Table 1 below.

(39) TABLE-US-00001 TABLE 1 Storage Elastic Tensile Modulus Viscosity Strength Adhesion Example 2 23000 Pa 3200 cps 0.14 MPa 700 gf/15 mm C. Example 1 22000 Pa 3300 cps 0.04 MPa 500 gf/15 mm C. Example 2 28000 Pa 4000 cps 0.05 MPa 350 gf/15 mm C. Example 3 45000 Pa 2000 cps 0.10 MPa 100 gf/15 mm (C. Example: Comparative Example)

(40) From Table 1, it can be confirmed that the curable composition containing the specific compound of the present application exhibits proper cohesiveness, tensile strength and adhesion without excessively increasing the elastic modulus, if it is cured, while showing proper viscosity before curing.