KR101647392B1 - 2 layer coextruding retro-reflection film and preparing method of thereof - Google Patents

Abstract

The present invention relates to a retroreflective film having a two-layer structure and a method of manufacturing the same. More specifically, the present invention relates to a retroreflective film having a two-layer structure and having similar or improved weatherability as a conventional retroreflective film, To a retroreflective film having a two-layer structure and a manufacturing method thereof.

Description

[0001] The present invention relates to a two-layer coextruded retroreflective film,

The present invention relates to a retroreflective film having a two-layer structure and a method of manufacturing the same. More specifically, the present invention relates to a retroreflective film having a two-layer structure and having similar or improved weatherability as a conventional retroreflective film, To a retroreflective film having a two-layer structure and a manufacturing method thereof.

A retroreflective film (or sheet) generally refers to a reflective sheet that reflects light in a direction parallel to incident light, as opposed to being reflected at the same angle as its incident angle when light is incident. Such a retroreflective film reflects light toward the light source It is very widely used for safety belts, traffic signs, apparel materials and so on.

The conventional retroreflective film has a disadvantage that it is difficult to manufacture because of its very complicated shape. Korean Unexamined Patent Publication No. 2002-96570 of the prior art discloses a method for manufacturing a retroreflective film, in which a retroreflective sheet is formed of a glass or a sheet form made of an optically transparent material such as polymethylmethacrylate And one side of the sheet was processed in such a manner that cube corners were continuously arranged on one side of the sheet. The above-mentioned method is a method using glass beads, in which fine glass beads are uniformly coated on a fabric or a film at a density of about 130,000 per square inch to return incident light to the direction of the light source. In particular, In order to improve the performance of the reflection, special coating is applied to the back of the glass beads. However, this method has a problem in durability because the adhesion of the glass beads to the film is lowered.

The conventional retroreflective sheet of the micro prism type has a shape as shown in Fig. 1 and / or Fig. As shown in Fig. 1 and / or Fig. 2, the retroreflective sheet of the micro prism type is provided with a base layer (or base film 3), and a plurality of fine microstructured prism layers 4 are formed on the bottom surface thereof. In order to improve the weatherability and scratch resistance of the micro-prism, the light incident on the fine micro-prism forms a retroreflection toward the light source. The body layer 1 is formed, and high-frequency or ultrasonic waves And an adhesive layer 2 was formed through adhesion, thermal bonding or adhesive. Such a retroreflective sheet having a four-layer structure and / or a three-layer structure including an adhesive layer is not suitable for peeling and miniaturization of a retroreflective product, which is a recent trend, (Or sheets) constituting each layer have to be produced and then laminated, so that the manufacturing process is complicated and the cost of the product is increased There has been a problem of lowering the economic efficiency.

The reason why the body film of the thermoplastic resin material such as urethane resin or acrylic resin and the film having the pattern formed thereon have to be laminated by a method such as an adhesive or a thermal bonding in the conventional manner is that the thermoplastic resin (Film) is peeled off. In addition, there is a problem that the flowability of the general-purpose acrylic resin and the compatibility with the general-purpose poly Due to the difference in the flowability of the carbonates, the appearance of the surface of the pneumatically released surface was lowered, and these layers could not be manufactured by the single die coextrusion method.

In addition, the retroreflective sheet produced by the conventional method for producing a retroreflective sheet has a problem of poor appearance quality.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above-mentioned problems, and an object of the present invention is to provide a retroreflective film which has a two-layer structure and has a weather resistance similar to that of a conventional retroreflective film, A retroreflective film having a two-layer structure and a method for producing the same.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a method for producing an acrylonitrile-butadiene copolymer, which comprises at least one of polymethyl methacrylate, cyanoacrylate and alpha-methylstyrene acrylonitrile (AMSSAN) A first layer comprising an acrylic resin and a UV stabilizer; A second layer comprising a polycarbonate resin and having a pattern formed on one surface thereof; And a ratio of a melting index (MI) of the acrylic resin to a melting index (MI) of the polycarbonate resin is 1: 5 to 10.

According to a preferred embodiment of the present invention, the acrylic resin of the retroreflective film of the two-layer structure of the present invention has a melt index of 2 to 4 and the melt index of the polycarbonate resin may be 12 to 40. [

According to a preferred embodiment of the present invention, the acrylic resin of the two-layer retroreflective film of the present invention has a melt index of 2.5 to 3.5 and a melt index of the polycarbonate resin of 15 to 30.

According to a preferred embodiment of the present invention, the first layer of the retroreflective film of the two-layer structure of the present invention may contain 0.001 to 10.0 parts by weight of a UV stabilizer per 100 parts by weight of the acrylic resin.

According to a preferred embodiment of the present invention, the UV stabilizer of the retroreflective film of the two-layer structure of the present invention may comprise at least one of benzotriazole, benzophenone, HALS and triazine-based compounds.

According to a preferred embodiment of the present invention, the second layer of the retroreflective film of the two-layer structure of the present invention has a tetrahedron pattern having a length of one side of the bottom surface and a height ratio of the pattern of 1 to 1.5: 1 .

According to a preferred embodiment of the present invention, the total thickness of the retroreflective film of the two-layer structure of the present invention may be 170 to 310 탆.

According to a preferred embodiment of the present invention, the thickness of the body layer of the retroreflective film of the two-layer structure of the present invention is 30 to 90 탆, and the thickness of the pattern layer may be 142 to 214 탆.

On the other hand, the present invention relates to a process for co-extruding an acrylic resin and a polycarbonate resin containing at least one of polymethylmethacrylate, cyanoacrylate and alpha-methylstyrene acrylonitrile (AMSSAN) A step of preparing a two-layer structure film in which a first layer and a polycarbonate layer are bonded to each other; And forming a pattern on one surface of the polycarbonate layer; Wherein the ratio of the melt index (MI) of the acrylic resin to the melt index (MI) of the polyketone resin is 1: 5 to 10, to provide.

Further, the present invention relates to a process for producing a UV-stabilized acrylic resin and a polycarbonate resin containing at least one of polymethyl methacrylate, cyanoacrylate and alpha-methylstyrene acrylonitrile (AMSSAN) A retroreflective film having a two-layer structure in which a first layer and a second layer are integrated is produced by forming a pattern on one surface of a polycarbonate layer, and the melt index (MI) of the acrylic resin and the polyketone And a ratio of a melt index (MI) of the resin is 1: 5 to 10.

According to a preferred embodiment of the present invention, the acrylic resin of the two-layer retroreflective film producing method of the present invention has a melt index of 2.5 to 3.5 and the polycarbonate resin may have a melt index of 15 to 30.

According to a preferred embodiment of the present invention, the method for producing a retroreflective film having a two-layer structure of the present invention may include 0.001 to 10.0 parts by weight of a UV stabilizer per 100 parts by weight of the acrylic resin.

According to a preferred embodiment of the present invention, the pattern of the two-layer retroreflective film manufacturing method of the present invention can be formed using a pattern roll.

According to a preferred embodiment of the present invention, the co-extrusion of the two-layer retroreflective film manufacturing method of the present invention is carried out at an extrusion temperature of 200 to 270 DEG C, an extrusion Klanter line pressure of 0.6 to 2 kN and an extrusion rate of 5 to 25 m / min . ≪ / RTI >

According to a preferred embodiment of the present invention, the twist angle (°) of the co-compressed acrylic resin and polycarbonate resin of the two-layer retroreflective film manufacturing method of the present invention may be 20 ° or less.

The retroreflective film of the present invention having a two-layer structure and the method of producing the same have a two-layer structure, and have a weather resistance similar to that of a conventional retroreflective film, and excellent appearance quality.

1 and 2 are sectional views of a conventional retroreflective film, wherein FIG. 1 is a sectional view of a retroreflective film having a four-layer structure, and FIG. 2 is a sectional view of a retroreflective film having a three-layer structure.
3 is a schematic view of a retroreflective film of the present invention in which a first layer 10 and a polycarbonate layer 20 'are joined or integrated, according to an embodiment of the present invention.
4 is a schematic view of a retroreflective film of the present invention in which a first layer 10 and a second layer 20 are joined or integrated by coextrusion and pattern formation.
5 is a schematic view showing a state in which an acrylic resin 11 having a melt index of 3 and a polycarbonate resin 22 having a melt index of 22 are co-extruded in the co-extrusion die 100 according to an embodiment of the present invention.
6 is a schematic view showing a state in which an acrylic resin 11 'having a melt index of 3 and a polycarbonate resin 22' having a melt index of 7 are co-extruded in the co-extrusion die 100.
7 is a schematic view showing a state in which an acrylic resin 11 '' having a melt index of 3 and a polycarbonate resin 22 '' having a melt index of 80 are co-extruded in the co-extrusion die 100.
Figs. 8 and 9 are schematic views of one embodiment of the pattern form of the second layer, Fig. 5 is a schematic view of the pattern plane, and Fig. 6 is a schematic view of the pattern cross section.
10 is a schematic view of a manufacturing process of a retroreflective film having a two-layer structure of the present invention.
Fig. 11 is a schematic diagram of the angle of incidence of the acrylic resin 11 '''and the polycarbonate resin 22''' co-extruded in the co-extrusion die 100, according to an embodiment of the present invention.
12 is an external view of a retroreflective film of a two-layer structure manufactured according to Example 1. Fig.
13 is an external view of a retroreflective film having a two-layer structure produced according to Comparative Example 1. Fig.

Hereinafter, the present invention will be described in more detail.

As described above, the reason why the conventional body film of a thermoplastic resin material such as urethane resin or acrylic resin and a film having a pattern formed thereon can not be laminated by a method such as an adhesive or a thermal bonding, The compatibility between the thermoplastic resin and the resin used in the patterned film is reduced and the adhesiveness between the thermoplastic resin and the resin used in the patterned film is deteriorated to cause detachment of the pattern layer (film). In addition, Due to the difference in the flowability of the general-purpose polycarbonate, there was a problem that the appearance of the surface of the pneumatic launching dropped, and these layers could not be manufactured by the single-die co-extrusion method. In addition, the retroreflective sheet produced by the conventional method for producing a retroreflective sheet has a problem of poor appearance quality.

Accordingly, the present invention relates to an acrylic resin containing at least one of polymethyl methacrylate, cyanoacrylate and alpha-methyl styrene acrylonitrile (AMSSAN) A first layer containing a stabilizer and a second layer containing a polycarbonate resin and having a pattern formed on one surface thereof, wherein a melt index (MI) of the acrylic resin and a viscosity of the polyketone resin Layer structure having a melt index (MI) of 1: 5 to 10, the present inventors have sought to solve the above-mentioned problems, A retroreflective film having a two-layer structure which is similar to the conventional retroreflective film and has excellent weatherability as well as an excellent appearance quality, and a method for producing the same.

The retroreflective film of the two-layer structure of the present invention includes a first layer 10 and a second layer 20, as shown in Fig.

The first layer 10 is a kind of bady layer comprising an acrylic resin and a UV stabilizer. The acrylic resin may be selected from the group consisting of polymethyl methacrylate, cyanoacrylate, And alpha-methyl styrene acrylonitrile (AMSSAN), and may include at least one of polymethyl methacrylate, and the polymethyl methacrylate The use of polymethyl methacrylate may be good for pneumatic discharge with polycarbonate resin.

The UV stabilizer is contained in the first layer 10 and serves to enhance the weatherability of the retroreflective film of the two-layer structure of the present invention.

The UV stabilizer may include at least one compound selected from the group consisting of benzotriazole, benzophenone, HALS, and triazine, preferably a benzotriazole-based compound.

A list of such UV stabilizers can be found in Stabilization of Poymeric Materials, Appendix 3, edited by Hans Zweifel, Springer, pages 181 to 213, which is incorporated herein by reference.

If the UV stabilizer is contained in an amount of less than 0.001 part by weight, the effect of improving the weatherability may be insignificant. When the UV stabilizer is added in an amount of more than 10.0 parts by weight , There may arise a problem in processing stability.

The second layer 20 may include a polycarbonate resin as a pattern layer having a pattern formed on one surface thereof. By using a polycarbonate resin, the second layer 20 may be formed at a pneumatic discharge with an acrylic resin. have.

The ratio of the melting index (MI) of the acrylic resin to the melting index (MI) of the polycarbonate resin may be 1: 5 to 10, preferably 1: 7 to 9 have.

If the ratio of the melting index (MI) of the acrylic resin to the melting index (MI) of the polycarbonate resin is out of the range of 1: 5 to 10, then the acrylic resin and the polycarbonate resin When the coextruded coin is extruded, a curvature is generated due to a difference in intrinsic viscosity between the coin-extruded coextruded coextruded coextruded coextruded coextensive coextruded coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial coaxial cable coaxial coaxial coaxial coaxial coaxial

More specifically, referring to Figs. 5 to 7, the following will be described.

5 is a schematic view showing a state in which an acrylic resin 11 having a melt index of 3 and a polycarbonate resin 22 having a melt index of 22 are co-extruded in the co-extrusion die 100. Referring to FIG. 5, The acrylic resin 11 and the polycarbonate resin 22 discharged from the coin dispenser 100 can be stably co-extruded without being inclined to either side of the co-extruding die 100 lip, in other words, The appearance surface of the produced retroreflective film may be good.

6 is a schematic view showing a state in which an acrylic resin 11 'having a melt index of 3 and a polycarbonate resin 22' having a melt index of 7 are simultaneously co-extruded in the co-extrusion die 100, The polycarbonate resin 22 'having relatively low intrinsic viscosity due to the intrinsic viscosity difference between the acrylic resin 11' and the polycarbonate resin 22 'discharged from the co-extrusion die 100 is co-extruded Extruded die 100 may be biased toward the lip of the co-extrusion die 100. In other words, a projectile is generated and co-extruded, and on the lip of the biased co-extrusion die 100, the residual oligomer is gradually formed, A die line may be formed on the surface of the reflective film to deteriorate the appearance quality.

Similarly, FIG. 7 is a schematic diagram showing a state in which an acrylic resin 11 '' having a melt index of 3 and a polycarbonate resin 22 '' having a melt index of 80 are co-extruded simultaneously in the co-extrusion die 100, 7, the acrylic resin 11 '' and the polycarbonate resin 22 '' discharged from the co-extrusion die 100 are made of an acrylic resin 11 '' having a relatively low intrinsic viscosity due to the intrinsic viscosity difference between the acrylic resin 11 ' In other words, a curve is generated and co-extruded so that the residual oligomer slowly forms on the lip of the biased co-extrusion die 100, which is biased toward the lip of the co-extrusion die 100 A die line may be formed on the surface of the produced retroreflective film to deteriorate the appearance quality.

The acrylic resin contained in the retroreflective film of the present invention has a melt index of 2 to 4, a melt index of 12 to 40, and more specifically, a two-layer structure of the present invention The melt index of the acrylic resin contained in the retroreflective film may be 2.5 to 3.5, the melt index of the polycarbonate resin may be 15 to 30, and the acrylic resin having such a melt index and the two- The retroreflective film of the structure can satisfy not only the best reflectance but also the appearance quality.

Furthermore, in the retroreflective film of the two-layer structure of the present invention, the pattern of the second layer 20 is not particularly limited, but the length of one side (a or b) of the bottom face and the pattern The height of the tetrahedron pattern having a height ratio of 1 to 1.5: 1 may preferably be formed with a length of one side (a or b) and a height of the pattern of 1.1 to 1.4: 1.

At this time, there may be a problem that the reflectivity falls when the length ratio of one side of the bottom surface to the height of the pattern is less than 1. When the length ratio of the length of one side of the bottom surface and the height of the pattern exceeds 1.5: 1, It is preferable to form the pattern so as to have a length ratio within the above range.

In the retroreflective film having a two-layer structure according to the present invention, the thickness of the first layer 10 and the second layer 20 is preferably 1.5 to 3.5: 8.5 to 6.5, And the thickness of the second layer 20 is 1.8 to 3.2: 8.2 to 6.3. At this time, if the thickness ratio of the first layer 10 to the second layer 20 is less than 1.5, the thickness of the first layer 10 is too thin, There is a problem that the ultraviolet (UV) blocking property is lowered when used, so that yellowing of the product may easily occur. If the thickness ratio of the first layer 10 is more than 3.5, the flexibility of the retroreflective film tends to deteriorate The first layer 10 and the second layer 20 may be formed so as to satisfy the thickness ratio.

Further, the total thickness of the retroreflective film of the two-layer structure of the present invention may be 170 to 310 탆, preferably 230 to 280 탆, wherein the first layer 10 of the retroreflective film of the two- The thickness of the second layer 20 may be 142 to 214 占 퐉, preferably 160 to 200 占 퐉. The thickness of the second layer 20 may be 30 to 90 占 퐉, preferably 70 to 80 占 퐉.

If the thickness of the second layer 20 of the retroreflective film having the above-described range is less than 142 탆, the flexibility of the retroreflective film may deteriorate and the problem of breakage may occur during the manufacturing process and use of the product. It is not preferable to peel off the retroreflective film.

Hereinafter, a method of manufacturing the above-described retroreflective film having a two-layer structure will be described.

The retroreflective film of the present invention having a two-layer structure is obtained by co-extruding an acrylic resin and a polycarbonate resin to which a UV stabilizer is added, as shown in FIG. 3, to form a first layer 10 and a second layer 20 ', to which the first layer 10 and the polycarbonate layer 20' A layered film may be first prepared and then a pattern may be formed on one surface of the polycarbonate layer 20 'as shown in FIG.

Another method of manufacturing the retroreflective film of the present invention is a method of producing a retroreflective film having a two-layer structure by forming a pattern layer simultaneously with coextrusion, and more specifically, The acrylic resin and the polycarbonate resin to which the UV stabilizer is added are co-extruded through the same process with the co-extrusion die 100 to produce a film in which the first layer 10 and the polycarbonate layer 20 ' A pattern is formed on one surface of the carbon layer 20 'using a pattern roll 200 to form a retroreflective film of a two-layer structure in which the first layer 10 and the second layer 20 are integrated Can be manufactured.

Conventionally, due to the difference between the compatibility of acrylic resin and polycarbonate resin, the flowability of general-purpose acrylic resin and the flowability of general-purpose polycarbonate, there has been a problem that the surface appearance of pneumatic pressure release is lowered, However, the present invention optimizes the flow characteristics of a resin such as an acrylic resin and a polycarbonate resin, and can produce an integrated film through co-extrusion through optimum extrusion process conditions. The extrusion process is preferably performed at an extrusion temperature of 200 to 270 DEG C, an extrusion calendering linear pressure of 0.6 kN to 2 kN, and an extrusion rate of 5 to 25 m / min. The acrylic resin and the polycarbonate resin It is possible to produce a film in which the layers of the material are integrated.

The acrylic resin may include at least one of polymethyl methacrylate, cyanoacrylate and alpha-methyl styrene acrylonitrile, And may include polymethyl methacrylate.

Further, the UV stabilizer added to the acrylic resin may include at least one of benzotriazole, benzophenone, HALS, and triazine compounds, and preferably a benzotriazole-based compound . If the UV stabilizer is contained in an amount of less than 0.001 part by weight, the effect of improving the weatherability may be insufficient. If the UV stabilizer is contained in an amount exceeding 1.0 part by weight, There may be a problem in stability.

The ratio of the melting index (MI) of the acrylic resin to the melting index (MI) of the polycarbonate resin may be 1: 5 to 10, preferably 1: 7 to 9 have.

If the ratio of the melting index (MI) of the acrylic resin to the melting index (MI) of the polycarbonate resin is out of the range of 1: 5 to 10, then the acrylic resin and the polycarbonate resin When the co-extruded product is extruded, a curvature is generated due to a difference in intrinsic viscosity between the co-extruded products. In other words, the curvature can be biased coaxially in one direction and the outer surface of the produced retroreflective film is not clean.

More specifically, referring to Figs. 5 to 7, the following will be described.

5 is a schematic view showing a state in which an acrylic resin 11 having a melt index of 3 and a polycarbonate resin 22 having a melt index of 22 are co-extruded in the co-extrusion die 100. Referring to FIG. 5, The acrylic resin 11 and the polycarbonate resin 22 discharged from the coin dispenser 100 can be stably co-extruded without being inclined to either side of the co-extruding die 100 lip, in other words, The outer surface of the produced retroreflective film can be clean.

6 is a schematic view showing a state in which an acrylic resin 11 'having a melt index of 3 and a polycarbonate resin 22' having a melt index of 7 are simultaneously co-extruded in the co-extrusion die 100, The polycarbonate resin 22 'having relatively low intrinsic viscosity due to the intrinsic viscosity difference between the acrylic resin 11' and the polycarbonate resin 22 'discharged from the co-extrusion die 100 is co-extruded Extruded die 100 may be biased toward the lip of the co-extrusion die 100. In other words, a projectile is generated and co-extruded, and on the lip of the biased co-extrusion die 100, the residual oligomer is gradually formed, A die line may be formed on the surface of the reflective film to deteriorate the appearance quality.

Similarly, FIG. 7 is a schematic diagram showing a state in which an acrylic resin 11 '' having a melt index of 3 and a polycarbonate resin 22 '' having a melt index of 80 are co-extruded simultaneously in the co-extrusion die 100, 7, the acrylic resin 11 '' and the polycarbonate resin 22 '' discharged from the co-extrusion die 100 are made of an acrylic resin 11 '' having a relatively low intrinsic viscosity due to the intrinsic viscosity difference between the acrylic resin 11 ' In other words, a curve is generated and co-extruded so that the residual oligomer slowly forms on the lip of the biased co-extrusion die 100, which is biased toward the lip of the co-extrusion die 100 A die line may be formed on the surface of the produced retroreflective film to deteriorate the appearance quality.

Further, the curvature angle (°) of the co-extruded acrylic resin and polycarbonate resin can be 20 ° or less, preferably 10 ° or less.

Specifically, as shown in FIG. 11, the acrylic resin 11 '''and the polycarbonate resin 22''' co-extruded in the co-extrusion die 100 are used as a prototype for producing a retroreflective film having a clean outer surface To be stably co-extruded, the engraving angle may be 20 degrees or less, and preferably 10 degrees or less. The incidence angle of the projections is the angle between the acrylic resin 11 '''and the polycarbonate resin 22''' co-extruded in the co-extrusion die 100 and the virtual line-to-line distance from the co- It means an angle (θ)

The present invention will now be described more specifically with reference to the following examples. However, the following examples should not be construed as limiting the scope of the present invention, and should be construed to facilitate understanding of the present invention.

Example

Example  One

Polymethyl methacrylate (LG MMA, HI835MU) having a melt index of 3 and acrylic resin having a melt index of 22 (Lotte Chemical, 1220SU) to which a UV stabilizer was added as an acrylic resin were coextruded in the same manner as described in Fig. Extruded at a extrusion temperature of 240 DEG C, an extrusion calender linear pressure of 1.0 kN and an extrusion rate of 5 m / min using a single die (100).

The first layer 10 and the polycarbonate layer 20 'are joined together through coextrusion and a pattern is formed on the one surface of the polycarbonate layer 20' using the pattern roll 200 180 占 퐉 in length on the bottom face and 147 占 퐉 in pattern height) to produce a retroreflective film having a two-layer structure in which the first layer 10 and the second layer 20 were integrated.

At this time, the total thickness of the retroreflective film of the two-layer structure was 253 탆, the thickness of the first layer was 75 탆, and the thickness of the second layer was 178 탆.

The retroreflective film having the above-prepared two-layer structure was visually observed and the results are shown in Table 1.

Example  2

Except that a polycarbonate resin (LG Chem, LUPOY1300-30) having a melt index of 30 was used instead of the polycarbonate resin having a melt index of 22, which was prepared in the same manner as in Example 1.

Example  3

Except that a polycarbonate resin (LG Chem, LUPOY1300-15) having a melt index of 15 was used instead of the polycarbonate resin having a melt index of 22 in the same manner as in Example 1.

Comparative Example  One

Except that a polycarbonate resin (LG Dow polycarbonate, 1080DVD) having a melt index of 80 was used instead of the polycarbonate resin having a melt index of 22, which was prepared in the same manner as in Example 1.

Comparative Example  2

Except that a polycarbonate resin (LG Chem, LUPOY1300-15) having a melt index of 7 was used instead of the polycarbonate resin having a melt index of 22, which was prepared in the same manner as in Example 1.

Comparative Example  3

Polymethyl methacrylate (LGMMA, HI835M) having a melt index of 3 was used in the same manner as in Example 1, except that a UV stabilizer was not added to the acrylic resin.

Experimental Example  One

(1) The appearance of the two-layered retroreflective film produced through the above Examples and Comparative Examples was visually observed, and the results are shown in Table 1.

(2) To evaluate the weatherability of the retroreflective film of the two-layer structure manufactured by the above Examples and Comparative Examples, the Q-lab corporation (QUV) was performed for 1000 hours. The stability was measured and the results are shown in Table 1. The color stability is preferably 3 or less.

division Example
One Example
2 Example
3 Comparative Example
One Comparative Example
2 Comparative Example
3

Two-layer retroreflective film Polycarbonate resin
Melt Index (MI) 22 30
15 80 7 22 The polymethylmethacrylate melt index (MI) 3 3 3 3 3 3 UV stabilizer
Whether to add ○ ○ ○ ○ ○ × Polycarbonate resin and polymethyl methacrylate co-extrusion stability Good Good Good Bad Bad Good Whether to form a die line none none none has exist has exist none Appearance of retroreflective film Good Good Good Bad Good Good ㅿ E 1.4 1.8 2.0 2.0 2.3 40

As can be seen from the above Table 1, unlike Comparative Examples 1 and 2, in the production of a retroreflective film having a two-layer structure in Examples 1 to 3, the polycarbonate resin and the polymethylmethacrylate co- It was confirmed that the appearance of the retroreflective film of the structure was good and no die line was formed.

Specifically, as shown in Fig. 12, it was confirmed that the retroreflective film of the two-layer structure manufactured in Example 1 had a good appearance of the retroreflective film and no die line was formed, and as shown in Fig. 13, It was confirmed that the retroreflective film of the two-layer structure manufactured in Example 1 had poor appearance of the retroreflective film and no die line was formed.

1: Body layer 2: Adhesive layer
3: base layer 4: prism layer
10: First layer
11, 11 ', 11'',11''': acrylic resin
20: Second layer 20 ': Polycarbonate layer
22, 22 ', 22'',22''': Polycarbonate resin
100: co-extrusion die 200: pattern roll

Claims (15)

And a UV stabilizer including an acrylic resin containing at least one of polymethyl methacrylate, cyanoacrylate and alpha-methyl styrene acrylonitrile (AMSSAN) A first layer; And
A second layer containing a polycarbonate resin and having a pattern formed on one surface thereof; / RTI >
The melt index (MI) of the acrylic resin is 2.5 to 3.0, the melt index (MI) of the polycarbonate resin is 25 to 30,
A coextruded retroreflective film having a two-layer structure, wherein the coextruded film has coarse extrusion (?) Of not more than 10 degrees.
delete delete The method according to claim 1,
Wherein the first layer comprises 0.001 to 10.0 parts by weight of a UV stabilizer per 100 parts by weight of the acrylic resin.
The method according to claim 1,
Wherein the UV stabilizer comprises at least one of benzotriazole, benzophenone, HALS and triazine-based compounds.
The method according to claim 1,
Wherein the second layer is formed with a tetrahedron pattern having a length of one side of the bottom surface and a height ratio of the pattern of 1 to 1.5: 1.
The method according to claim 1,
Wherein the total thickness of the retroreflective film is 170 to 310 占 퐉.
8. The method of claim 7,
Wherein the thickness of the first layer of the retroreflective film is 30 to 90 占 퐉 and the thickness of the second layer of the retroreflective film is 142 to 214 占 퐉.
(˚) 10 of co-extruded pieces of an acrylic resin and polycarbonate resin containing at least one of polymethyl methacrylate, cyanoacrylate and alpha-methylstyrene acrylonitrile (AMSSAN) to which a UV stabilizer is added Lt; RTI ID = 0.0 >#< / RTI > to produce a two-layer structure film wherein the first layer and the polycarbonate layer are bonded; And
Forming a pattern on one surface of the polycarbonate layer; Lt; / RTI >
Wherein the acrylic resin has a melt index of 2.5 to 3.0, and the polycarbonate resin has a melt index of 25 to 30.
(˚) 10 of co-extruded pieces of an acrylic resin and polycarbonate resin containing at least one of polymethyl methacrylate, cyanoacrylate and alpha-methylstyrene acrylonitrile (AMSSAN) to which a UV stabilizer is added And simultaneously forming a pattern on one surface of the polycarbonate layer to produce a retroreflective film having a two-layer structure in which the first layer and the second layer are integrated,
Wherein the acrylic resin has a melt index of 2.5 to 3.0, and the polycarbonate resin has a melt index of 25 to 30.
delete 11. The method according to claim 9 or 10,
Wherein the UV-stabilizing agent comprises 0.001 to 10.0 parts by weight of a UV stabilizer based on 100 parts by weight of the acryl-based resin.
11. The method according to claim 9 or 10,
Wherein the pattern is formed using a pattern roll. ≪ RTI ID = 0.0 > 11. < / RTI >
11. The method according to claim 9 or 10,
Wherein the coextrusion is carried out under the conditions of an extrusion temperature of 200 to 270 DEG C, an extrusion kinetics linear pressure of 0.6 to 2 kN, and an extrusion rate of 5 to 25 m / min.

delete

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