KR101571853B1 - Polymer substrate having primer layer having improved adhesion to base film and optical substrate using the same - Google Patents

Abstract

The present invention relates to a polymer base material having a primer layer improved in adhesion to a base film and an optical base material using the polymer base material.

The polymer base material of the present invention comprises a primer layer formed by coating a polyurethane based binder resin composition containing a copolymer containing a sulfonate group (SO ₃ ^- ) and a crosslinking curing agent on a polyester base film layer, by containing a copolymer comprising a) the polymer chains in the copolymer sulphonate group (SO ₃ ^{- -} a poly sulfonate group O ₃ in the urethane resin) are continuously arranged, induces hydrogen bonding between the base film The adhesive force is excellent even for a UV curable resin which provides an excellent adhesive force and is used at the same time in post-processing. Thus, the polymer base material of the present invention maintains excellent adhesive force even under high temperature and high humidity conditions, and can be used for various optical members.

Polymer substrate, polyurethane, polyester, polyamide

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer substrate having a primer layer having improved adhesion to a substrate film, and an optical substrate using the polymer substrate. 2. Description of the Related Art [0002]

The present invention relates to a polymer base material having a primer layer having improved adhesion to a base film and an optical base material using the polymer base material. More particularly, the present invention relates to a polymer base material having a primer layer formed on a polyester base film layer, (SO < ₃ > ^- ), it is possible to improve the adhesive force with the base film and to exhibit excellent adhesion even to the UV curable resin used at the time of post-processing, Functional polymer substrate excellent in wetting property and an optical substrate using the same.

The polyester film is excellent in dimensional stability, thickness uniformity and optical transparency, and is widely used for various industrial materials as well as display devices.

When such a polyester film is used as a polyester-based functional polymer substrate for an optical member, a primer layer is constituted by using a copolymer polyester binder resin excellent in adhesion to a polyester base film, The resin has a sufficient adhesion with the polyester base material film, but has poor heat resistance, moisture resistance, and poor adhesion, and has excellent adhesiveness with other substrates such as a prism processing layer, a lens processing layer, an antireflection layer or a hard coating layer Lack.

Therefore, in order to solve the conventional problems, post-curing catalysts or polyurethane-based binder resins introduced into molecules are applied, and they are excellent in heat resistance and moisture resistance as well as adhesion to various UV curable resins used in post-processing.

However, the polyurethane-based binder resin is superior in heat resistance and adhesion to the UV cured resin at the time of post-processing, and has a problem in that adhesion strength with the polyester base film is insufficient at the time of adhesion test to detach the primer layer from the polyester base film layer Occurs.

Therefore, development of a binder resin and a functional polymer substrate which can provide heat resistance and moisture resistance so as to have an excellent adhesive strength to a UV curable resin which is excellent in adhesion to a polyester base film and used in post-processing is required.

An object of the present invention is to provide a polyurethane-based binder resin composition containing a copolymer in which a sulfonate group (SO ₃ ^- ) is continuously arranged in a polyurethane resin and a crosslinking curing agent.

Another object of the present invention is to provide a high-functional polymer base material having a primer layer formed by applying the polyurethane-based binder resin composition on at least one surface of a polyester base film layer.

Yet another object of the present invention is to provide a use as an optical substrate using the high-functional polymer substrate.

In order to achieve the above object, the present invention provides a polyester base film layer; And

Wherein at least one side of the base film layer is coated with a polyurethane resin represented by the following formula (I) in an amount of 1.0 to 90 wt%, a copolymer containing a sulfonate group (SO ₃ ^- ) in an amount of 1.0 to 60 wt%, a melamine- , A isocyanate-based compound, and an oxazoline-based compound, and a primer layer formed by a polyurethane-based binder resin composition in which 1.0 to 25% by weight of a crosslinking curing agent selected from the group consisting of an isocyanate-based compound and an oxazoline- .

(Wherein R is a hydroxyl group, an amine group or an aryl group, m is an integer of 0 to 10, and n is an integer of 1 or more).

The copolymer containing the sulfonate group (SO ₃ ^- ) contained in the polyurethane binder resin composition of the present invention is a structure in which a sulfonate group (SO ₃ ^- ) is continuously arranged in a chain of polymer chains, A polyester copolymer containing a sulfonate group represented by the general formula (2) or a polyamide copolymer containing a sulfonate group represented by the general formula (3).

(In the above, m is an integer of 0 to 10, and n is an integer of 1 or more.)

(In the above, m is an integer of 0 to 10, and n is an integer of 1 or more.)

The copolymer containing the sulfonate group (SO ₃ ^- ) contained in the polyurethane-based binder resin composition of the present invention shows weak acidity at pH 5 to 7 or less due to the sulfonate group (SO ₃ ^- ).

The polyurethane-based binder resin composition of the present invention may further contain 1.0 to 10% by weight of inorganic particles. At this time, the inorganic particles use silica particles or alumina-silica composite oxide particles having an average particle diameter of 30 to 500 nm.

In the polymer substrate of the present invention, the preferable thickness of the primer layer is 0.01 to 5.00 탆.

The polymer substrate of the present invention exhibits the functionality that satisfies the adhesive force of 70 to 100% between the base film layer and the primer layer after the 96 hour moisture resistance test under the conditions of 65 ° C and 95% humidity.

Further, an optical substrate having a light transmittance of 85% or more and a haze value of 0.3 to 2% or less is provided by using the polymer substrate of the present invention.

According to the present invention, it is possible to provide a polymer base material excellent in adhesion force to a UV curable resin used in post-processing, as well as in adhesion to a base film.

The polymer base material of the present invention comprises a primer layer formed by applying a polyurethane binder resin composition containing a copolymer containing a sulfonate group (SO ₃ ^- ) and a crosslinking curing agent on a polyester base film layer, , And a sulfonate group (SO ₃ ^- ) are continuously arranged to provide excellent adhesion with a substrate film.

Thus, the polymer base material of the present invention, which has excellent heat resistance and moisture resistance, can be used throughout various optical members which maintain excellent adhesion even under high temperature and high humidity conditions. In particular, the polymer substrate of the present invention can be usefully used as a plastic packaging material, a substrate for an LCD prism sheet, a substrate for a backlight, a substrate for a hard coat process, and a CRT protective substrate.

Hereinafter, the present invention will be described in detail.

The present invention relates to a polyester base film layer; And

1.0 to 90% by weight of a polyurethane resin represented by the following general formula (1)

1.0 to 60% by weight of a copolymer containing a sulfonate group (SO ₃ ^- ),

A primer layer formed from a polyurethane-based binder resin composition in which 1.0 to 25% by weight of a crosslinking curing agent selected from the group consisting of a melamine compound, an epoxy compound, an isocyanate compound and an oxazoline compound is dissolved in water in a remaining amount; ≪ / RTI >

Formula 1

(Wherein R is a hydroxyl group, an amine group or an aryl group, m is an integer of 0 to 10, and n is an integer of 1 or more).

In the polymer substrate of the present invention, the polyester base film layer may be selected from polyethylene terephthalate, polyethylene naphthalate or polycarbonate.

In the polymer substrate of the present invention, the polyurethane-based binder resin composition for forming the primer layer is characterized by adding a copolymer containing a sulfonate group (SO ₃ ^- ) to the polyurethane resin.

At this time, a preferable example of the copolymer containing a sulfonate group (SO ₃ ^- ) is a polyester copolymer containing a sulfonate group represented by the following formula (2).

(2)

(In the above, m is an integer of 0 to 10, and n is an integer of 1 or more.)

Further, another preferred example of the copolymer containing a sulfonate group (SO ₃ ^- ) is a polyamide copolymer containing a sulfonate group represented by the following formula (3).

(3)

In the above, m is an integer of 0 to 10, and n is an integer of 1 or more.

The addition of a copolymer containing a sulfonate group in which a sulfonate group (SO ₃ ^- ) is continuously arranged in a chain of polymer chains is added to the polyurethane-based binder resin composition of the present invention, which is advantageous for improving adhesion with a polyester base film layer.

That is, a polyurethane-based binder resin composition containing a copolymer containing a sulfonate group (SO ₃ ^- ) is applied onto a polyester base film layer to form a primer layer, thereby inducing hydrogen bonding with the polyester base film layer It is possible to prevent penetration of moisture and other solvent between the interface between the polyester base film layer as the main substrate and the interface between the polymer primer layer and improve the adhesion.

In addition, the primer layer formed of the polyurethane-based binder resin composition of the present invention is capable of reducing the phenomenon of trapping of the air layer between the interface by providing excellent adhesion with the polyester base film, thereby reducing the optical loss between the interface between the base film layer and the primer layer . That is, it is possible to reduce the loss of light between the interfaces and to impart excellent optical characteristics.

To improve durability, the polyurethane-based binder resin composition of the present invention contains 1.0 to 25% by weight of a crosslinking curing agent selected from the group consisting of a melamine compound, an epoxy compound, an isocyanate compound and an oxazoline compound. If the amount is less than 1.0 wt%, the crosslinking reaction is insufficient, resulting in poor durability. If the amount is more than 25 wt%, durability is deteriorated due to an excessive increase in the degree of curing and self-reaction of the curing agent.

In the polymer base material of the present invention, the polyurethane-based binder resin composition constituting the primer layer further contains 1.0 to 10% by weight of inorganic particles having a relatively small difference in refractive index from the resin contained in the primer layer, thereby ensuring the drivability. In this case, the average particle size of the inorganic particles is preferably 30 to 500 nm, more preferably 50 to 300 nm. When the average particle size is less than 30 nm, the fine inorganic particles do not contribute to the running property and scratch resistance of the substrate, The effect of injecting the particles is not given. If the average particle size of the fine particles exceeds 500 nm, there arises a problem that the haze is interfered.

As the inorganic particles used in the present invention, silica particles or alumina-silica composite oxide particles are used. If the content of the inorganic particles of the present invention is less than 1.0% by weight, it is not effective for running and is susceptible to scratches. If the content of the inorganic particles exceeds 10% by weight, it affects the turbidity of the product and becomes opaque.

In the polymer substrate of the present invention, the primer layer is preferably formed to a thickness of 0.01 to 5.00 탆, more preferably 0.05 to 3.00 탆. At this time, if the thickness of the primer layer is thinner than 0.01 탆, the transparency becomes good, but the adhesive force decreases at the time of post-processing, and when it is thicker than 5.00 탆, the adhesive property is excellent but transparency and coating property are deteriorated.

The polyurethane-based binder resin composition of the present invention may further contain an additive, if necessary, in order to improve coatability and functionality. Examples thereof include a surfactant, a defoaming agent, and the like.

From the above, it can be seen that the polymer base of the present invention has a primer layer excellent in adhesion to the polyester base film layer, so that the adhesive force between the base film layer and the primer layer after the 96 hour moisture resistance test under the conditions of 65 캜 and 95% 70 to 100%.

In addition, since the primer layer of the present invention exhibits excellent adhesion with the UV resin at the time of post-processing, the primer layer of the present invention is excellent in post-processing suitability such as transportability of the substrate in the heat treatment process, .

Accordingly, the present invention provides an optical substrate using the functional polymer substrate.

The polymer base material of the present invention has an excellent adhesion strength between the polyester base film layer and the primer layer, and improves the adhesive force and the adhesion of the moisture resistance to other base materials coated on the polymer primer layer at the time of post-processing.

In addition, the polymer base material of the present invention is characterized in that a primer layer is formed of a polyurethane-based binder resin composition on a polyester base film, and the polyurethane-based binder resin composition contains a copolymer containing a sulfonate group (SO ₃ ^- It is possible to reduce the phenomenon that the air layer between the interface is trapped effectively by being in intimate contact with the polyester base film. As a result, optical loss between the base film layer and the interface between the primer layer can be reduced, and loss of light between the interfaces can be reduced and excellent optical characteristics can be imparted.

Therefore, the polymer base material of the present invention is useful as a plastic packaging material, a base material for LCD diffusing and prism sheet, a backlight base material, various hard coat processing or AR (anti-reflection) base material, CRT protection base material and the like.

In particular, the polymer substrate of the present invention can be utilized as an optical substrate of an optical polyester film due to the characteristics of a light transmittance of 85% or more and a haze value of 0.3 to 2% or less.

More specifically, the surface of the polymer substrate on which the primer layer of the present invention is formed satisfies 95% to 100% of adhesion, 85% or more of total light transmittance, 0.3 to 2% of haze, more preferably 0.4 to 1.8% do.

Hereinafter, the present invention will be described in more detail with reference to Examples.

The present invention is intended to more specifically illustrate the present invention, and the scope of the present invention is not limited to these embodiments.

≪ Example 1 >

28% by weight of urethane resin Water dispersion 15% by weight (solids weight 4.2% by weight); 15% by weight (solids weight 4.5% by weight) of an aqueous dispersion containing 30% by weight of a polyester copolymer (m = 1, n = 5) containing a sulfonate group; 30% by weight of melamine-based crosslinking curing agent 5% by weight of water dispersion (solids weight 1.5% by weight); 10% by weight of an anionic surfactant 1.0% by weight of an aqueous dispersion (solids weight 0.1% by weight); A polyurethane binder resin composition was prepared by mixing 0.1 wt% (solid content weight 0.07 wt%) of an aqueous dispersion containing 70 wt% of colloidal silica particles having a particle size of 80 nm and 63.9 wt% of water.

Thereafter, the polyurethane-based composition was applied to a polyethylene terephthalate (PET) base film to prepare a polymer base having a primer layer with a thickness of 188 탆.

≪ Example 2 >

Based binder resin composition prepared in Example 1, except that the polyurethane-based binder resin composition prepared in Example 1 contained 5% by weight of an aqueous dispersion containing 30% by weight of an epoxy cross-linking curing agent. Of a polymer substrate having a primer layer formed thereon was prepared.

≪ Example 3 >

Based binder resin composition prepared in Example 1, except that it contained 5% by weight of an aqueous dispersion containing 30% by weight of an isocyanate crosslinking curing agent, and this was carried out in the same manner as in Example 1 to obtain a 188 탆 thick Of a polymer substrate having a primer layer formed thereon was prepared.

<Example 4>

The binder composition was the same as that of the polyurethane-based binder resin composition prepared in Example 1 except that it contained 5% by weight of an aqueous dispersion containing 30% by weight of an oxazoline crosslinking curing agent. Thereby preparing a polymer base material having a primer layer of a thickness.

&Lt; Example 5 >

The procedure of Example 1 was repeated except that the polyamine-based binder resin composition containing a melamine crosslinking curing agent of Example 1 was applied to a polyethylene naphthalate (PEN) base film to prepare a polymer having a primer layer with a thickness of 188 탆 Substrate.

&Lt; Example 6 >

The procedure of Example 1 was repeated except that the polyurethane-based binder resin composition containing isocyanate crosslinking and curing agent of Example 2 was applied to a polyethylene naphthalate (PEN) base film to prepare a polymer having a primer layer with a thickness of 188 탆 Substrate.

&Lt; Example 7 >

The procedure of Example 1 was repeated except that the polyurethane-based binder resin composition containing isocyanate crosslinking and curing agent of Example 3 was applied to a polyethylene naphthalate (PEN) base film to prepare a polymer having a primer layer with a thickness of 188 탆 Substrate.

&Lt; Example 8 >

A primer layer having a thickness of 188 탆 was formed by performing the same method as in Example 1 except that the polyurethane-based binder resin composition containing an oxazoline crosslinking curing agent of Example 4 was applied to a polyethylenenaphthalate (PEN) To prepare a polymer substrate.

&Lt; Example 9 >

Except that a polyurethane binder resin composition containing a melamine crosslinking and curing agent of Example 1 was applied to a polycarbonate (PC) base film, a polymer substrate having a primer layer with a thickness of 188 탆 was formed .

&Lt; Example 10 >

The procedure of Example 1 was repeated except that the polyurethane-based binder resin composition containing an isocyanate crosslinking and curing agent of Example 2 was applied to a polycarbonate (PC) base film to prepare a polymer substrate having a primer layer with a thickness of 188 탆 .

&Lt; Example 11 >

Except that a polyurethane-based binder resin composition containing an isocyanate crosslinking and curing agent of Example 3 was applied to a polycarbonate (PC) base film, a polymer substrate having a primer layer with a thickness of 188 탆 was formed .

&Lt; Example 12 >

The procedure of Example 1 was repeated except that the polyurethane-based binder resin composition containing the oxazoline crosslinking curing agent of Example 4 was applied to a polycarbonate (PC) base film to prepare a polymer having a primer layer with a thickness of 188 탆 Substrate.

&Lt; Example 13 >

Except that 15 wt% of an aqueous dispersion containing 30 wt% of a polyester copolymer (m = 1, n = 8) containing a sulfonate group was used instead of the polyester resin .

&Lt; Example 14 >

Except that a polyamide copolymer containing a sulfonic acid group (m = 2 and n = 5) was prepared by the same method as in Example 1, to thereby prepare a polymer substrate.

&Lt; Example 15 >

A polymer substrate was prepared by carrying out the same polyurethane-based binder resin composition and method as in Example 1, except that the polyamide copolymer (m = 2, n = 8) containing sulfonic acid groups was contained.

&Lt; Example 16 >

A polymer substrate was prepared in the same manner as in Example 1, except that a polyurethane-based binder resin composition containing no colloidal silica particles was used in Example 1.

&Lt; Example 17 >

Except that the colloidal silica particles used in Example 1 were replaced by 0.1 wt% of an aqueous dispersion containing 70 wt% of alumina-silica composite oxide particles having a particle size of 80 nm, instead of the colloidal silica particles used in Example 1, the polyurethane- And a method were used to prepare a polymer substrate.

&Lt; Comparative Example 1 &

Except that a polyester copolymer containing a sulfonate group was not contained, a polymer base was prepared by performing the same with the polyurethane-based binder resin composition and method as in Example 1 containing a melamine crosslinking curing agent.

&Lt; Comparative Example 2 &

Except that a polyester copolymer containing a sulfonate group was not contained, a polymer base was prepared by carrying out the same polyurethane binder resin composition and method as in Example 2 containing the above epoxy crosslinking curing agent.

&Lt; Comparative Example 3 &

Except that a polyester copolymer containing a sulfonate group was not contained, a polymer substrate was prepared by carrying out the same polyurethane binder resin composition and method as in Example 3 containing the isocyanate crosslinking curing agent.

&Lt; Comparative Example 4 &

Except that a polyester copolymer containing a sulfonate group was not contained, a polymer substrate was prepared by carrying out the same polyurethane-based binder resin composition and method as in Example 4 containing the above-mentioned oxazoline crosslinking curing agent.

&Lt; Comparative Example 5 &

Except that a polyamide copolymer containing a sulfonate group was not contained, a polymer base material was prepared by carrying out the same polyurethane binder resin composition and method as in Example 1 containing a crosslinking curing agent.

&Lt; Comparative Example 6 >

Except that a polyamide copolymer containing a sulfonate group was not contained, a polymer base was prepared by carrying out the same polyurethane-based binder resin composition and method as in Example 2 containing the epoxy cross-linking curing agent.

&Lt; Comparative Example 7 &

Except that a polyamide copolymer containing a sulfonate group was not contained, a polymer substrate was prepared by carrying out the same polyurethane binder resin composition and method as in Example 3 containing the isocyanate crosslinking curing agent.

&Lt; Comparative Example 8 >

Except that a polyamide copolymer containing a sulfonate group was not contained, a polymer base material was prepared by carrying out the same polyurethane-based binder resin composition and method as in Example 4 containing the above-mentioned oxazoline crosslinking curing agent.

Experimental Example 1 Measurement of Adhesion between Primer Layer-coated Base Film and UV Resin at Post-Processing

The polymer base materials prepared in the above Examples and Comparative Examples were measured for adhesion strength after curing with a base film layer and a UV resin mainly used in post-processing.

Specifically, an acrylic UV curable resin was applied to a surface to which a primer layer was adhered by using a # 20 wire bar, and after curing by UV irradiation, the cured UV resin was cut into a film coated with a primer layer by a cutter A line was made and 2 mm x 2 mm squares were placed in a 10 x 10 matrix. A cellophane tape (No. 405, made by NICHIBAN; width: 24 mm) was attached to the film having the cut line, and the tape was rubbed to be strongly adhered to the film using a velvet. Thereafter, the tape was peeled vertically and the area of the primer layer remaining on the adhesive layer was visually observed, and the adhesive force was calculated by the following formula (1 ).

Also, an adhesion test for evaluating moisture resistance after 96 hours under the conditions of 65 占 폚 and 90% humidity was carried out in the same manner.

<Experimental Example 2>

The coating properties between the primer layer coating liquid and the substrate were measured for the polymer substrates prepared in the above-described Examples and Comparative Examples. Specifically, the primer layer was observed on the surface of the substrate before application and the surface after application using # 0 to # 4 wire bars.

At this time, the coating solution should not be visually imprinted like an island, and when the number of parts where the coating solution is not applied is less than 2, such as Ireland, it is judged to be excellent.

From the above results, it was confirmed that the base resin of the polyurethane contained a polyester or polyamide copolymer containing a sulfonate group (SO ₃ ^- ), so that after the test of wettability in 96 hours under the conditions of 65 ° C and 95% The adhesion between the film layer and the primer layer was 100%. Therefore, adhesion is expected to be improved due to securing heat resistance and moisture resistance.

In addition, the adhesive property (%) with the UV resin in the post-processing also satisfies 100%, thereby exhibiting excellent adhesion with other substrates.

As described above, the present invention relates to a polyurethane based binder resin composition containing a polyester or polyamide copolymer containing a sulfonate group (SO ₃ ^- ) in a base resin of a polyurethane on a polyester base film Thereby providing a high-functional polymer substrate having a primer layer formed thereon. The polymer base material of the present invention exhibits excellent adhesion strength of 100% between the polyester base film layer and the primer layer under the conditions of high temperature and high humidity, thereby solving the conventional problem of deterioration of adhesion due to heat resistance and moisture resistance.

In addition, since the post-processability such as the transportability of the polymer substrate is excellent in the heat treatment process of post-processing such as prism lens processing of the polymer base material of the present invention, hard coat processing, AR processing, etc., , A substrate for LCD prism sheet, a substrate for backlight, a substrate for hard coat processing AR, and a substrate for CRT protection.

While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (9)

Based base film layer and a primer layer formed from a polyurethane-based binder resin composition on at least one side of the base film layer, The polyurethane-based binder resin composition may contain, 1.0 to 90% by weight of a polyurethane resin represented by the following general formula (1) A polyester copolymer comprising a sulfonate group of the following formula (2) or a polyamide copolymer containing a sulfonate group of the following formula ( ₃ ), wherein the sulfonate group (SO ₃ ^- ) is continuously arranged on the chain of the polymer chain weight%, By weight of a crosslinking curing agent selected from the group consisting of a melamine-based compound, an epoxy-based compound, an isocyanate-based compound and an oxazoline-based compound is dissolved in a residual amount of water. Formula 1

(Wherein R is a hydroxyl group, an amine group or an aryl group, m is an integer of 0 to 10, and n is an integer of 1 or more) (2)

(Wherein m is an integer of 0 to 10 and n is an integer of 1 or more) (3)

(Wherein m is an integer of 0 to 10, and n is an integer of 1 or more). delete delete delete The polymer base material according to claim 1, further comprising 1.0 to 10% by weight of inorganic particles in the polyurethane-based binder resin composition. The polymer substrate according to claim 5, wherein the inorganic particles are silica particles or alumina-silica composite oxide particles having an average particle diameter of 30 to 500 nm. The polymer base material according to claim 1, wherein the thickness of the primer layer is 0.01 to 5.00 μm. The polymer substrate according to claim 1, wherein the functional polymer substrate satisfies an adhesive force of 70 to 100% between the base film layer and the primer layer after the 96 hours of wet test under the conditions of 65 占 폚 and 95% humidity. An optical substrate having a light transmittance of 85% or more and a haze value of 0.3 to 2% or less using the polymer substrate of claim 1.