KR20070097911A - Sticker type retro reflection sheet and manufacturing method thereof - Google Patents

Abstract

A retroreflective sheet having glass beads and a manufacturing method thereof are provided to secure a retroreflection effect by easily applying the retroreflective sheet to an object through cutting and attachment. A retroreflective sheet having glass beads comprises the followings: a bead containing adhesion layer(11) formed by coating of the mixture of the glass beads and transparent synthetic resin; a metal layer(12) laminated on the bead containing adhesion layer; an adhesive layer(13) laminated on the metal layer; and a release liner(131) attached on the adhesive layer. The bead containing adhesion layer comprises a surface layer(111), a glass bead layer(112), and a focusing layer(113). In particular, the bead containing adhesion layer is formed by applying and drying a bead coating solution produced by mixing the glass beads and the transparent synthetic resin selected from a group comprising polyacrylic resin, polyester, polyurethane, alkyd, and the mixture thereof. The glass beads of 50~300wt.% are mixed with the transparent synthetic resin.

Description

Retroreflective sheet containing glass beads and its manufacturing method {Sticker type retro reflection sheet and manufacturing method

1 is a side cross-sectional view showing one specific example of a conventional retroreflective sheeting.

Figure 2 is a side cross-sectional view showing one specific example of the retroreflective sheet according to the present invention.

Figure 3 is a side cross-sectional view showing one specific example of the manufacturing method of the retroreflective sheet according to the present invention.

Explanation of symbols on the main parts of the drawings

1: surface layer 2: binder layer

3: glass bead 4: focus layer

5: metal layer 6: adhesive

7: Release Liner

11: Hammed layer 12: Metal layer

13: adhesive layer

21: leading film

111 surface layer 112 glass bead layer

113: focal layer

131: release liner 132: pressure-sensitive adhesive

The present invention relates to a retro-reflective sheet using glass beads and a method of manufacturing the same, in particular, a retro-reflective effect that can be easily applied by cutting and attaching according to simple printing and design where retroreflective is needed. A sheet and a method for producing the same.

The reflection of light can be roughly divided into diffuse reflection, mirror reflection and retroreflection (recursive reflection).

In retroreflective sheeting, retroreflection refers to the reflection of light from a light source back at the surface of an object and back to the light source. The material that causes this retroreflection is the retroreflective sheet, but it reflects light in the direction of the light source even if it reflects the light on the retroreflective sheet at any angle, and when the headlight or fresh light of the car is illuminated on the retroreflective sheet The light source is easily visible to the person in the light source, and thus is easy to identify at night, and is widely used for warning of traffic signs and other safety phrases for drawing attention at night.

The retroreflection is mainly performed by the glass bead reflector or the cube reflector by fixing the glass bead reflector or the cube reflector on the surface of the object, and the glass bead reflector is widely used due to the ease of manufacture. One specific example of the retroreflective sheet using is shown in FIG. 1.

As shown in FIG. 1, the conventional retroreflective sheet is formed by laminating the surface layer 1, the binder layer 2, the glass bead 3, the focus layer 4, and the metal layer 5 sequentially from the top. The surface layer 1 serves to protect the interior, and mainly consists of a coating of a transparent synthetic resin such as acrylic, alkyd, urethane, ester, and olefin. The surface layer 1 may be composed of two or more layers, and when the two or more layers are used, they are used for controlling physical properties and the like. The glass bead 3 is a medium material for imparting a retroreflective function in the retroreflective sheet. The glass bead 3 is made of glass as a main material, and incident light is focused outside the bead. The focus layer 4 serves to reduce or tailor the distance between the bead surface and the focus of the incident light formed outside the bead. The metal layer 5 is formed on the focal layer 4 and functions to reflect incident light back toward the incident light source. The glass beads 3 are arranged and fixed in a single layer by the binder layer 2, and the synthetic resin constituting the binder layer 2 is made of transparent synthetic resins such as acrylic, alkyd, urethane, ester, and the like. As the resin constituting the focal layer 4, transparent resins such as acrylic, alkyd, urethane, ester, etc. are used, and the thickness thereof varies depending on the particle diameter and refractive index of the glass beads used, and is mainly proportional to the particle diameter of the glass beads. Shows a relationship. Light transmitted through the focus layer 4 is reflected by the metal layer 5 formed on the focus layer 4 and passes through the focus layer 4, the glass beads 3, the binder layer 2, and the surface layer 1. It is reflected back to the incident light source. The metal layer 6 advantageously has a high reflection efficiency and mainly aluminum is used.

On the other hand, in the case of the conventional retroreflective sheet having the above-described configuration, the surface layer (1), the binder layer (2), the glass bead (3), the focus layer (4) on the surface of the object that requires a direct retroreflective function , And the metal layer (5) in order to be formed by lamination, it has a disadvantage that takes a lot of time and effort. That is, each layer is made by a separate coating and requires five coatings.

The present invention has been made to solve the problems of the prior art as described above to simplify the retroreflective sheet manufacturing process, the product is easy to cut and attach to the desired shape through simple printing or design, to achieve this It is an object of the present invention to provide a method for producing a retroreflective sheet by coating and forming a metal layer on a leading film.

It is an object of the present invention to provide a retro-reflective sheet and a method for manufacturing the same, which can be easily applied by cutting and attaching a retro-reflective effect where a retro-reflection is required.

As described above, the retroreflective sheet including the glass beads according to the present invention includes a bead fixing layer, which is a surface layer formed by coating a mixture of glass beads and a transparent synthetic resin, a metal layer laminated on the bead fixing layer, and It comprises a pressure-sensitive adhesive layer laminated on a metal layer and a release liner attached to the pressure-sensitive adhesive layer, characterized in that the bead fixing layer is composed of a surface layer, a glass bead layer and a focus layer.

In addition, the manufacturing method of the retro-reflective sheet containing the glass bead of the present invention, (1) a bead fixation to form a bead fixing layer by coating and drying a mixture of glass beads and a transparent synthetic resin on the surface of the leading film Layer formation step; (2) forming a metal layer on the bead fixing layer; (3) a pressure-sensitive adhesive layer formed through a pressure-sensitive adhesive coating and drying on a release liner and a pressure-sensitive adhesive layer forming step of plywood it on a metal layer.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in Fig. 2, the reverse-reflective sheet including the glass beads according to the present invention is a surface bonding layer 11 formed of a coating of a mixture of glass beads and a transparent synthetic resin 11, the adhesion layer 11 The metal layer 12 is laminated on the metal layer 12, the pressure-sensitive adhesive layer 13 is laminated on the metal layer 12 and the release liner 131 attached to the pressure-sensitive adhesive layer 13, but the bead fixed The layer 11 is characterized by consisting of the surface layer 111, the glass bead layer 112 and the focusing layer 113.

The bead fixing layer 11 is formed by coating and drying a bead coating liquid consisting of glass beads and a transparent synthetic resin on a leading film, and the transparent synthetic resin constituting the bead coating liquid is polyacrylic resin, polyester, polyurethane And optically transparent synthetic resins such as alkyd and the like, which are exemplary, and the present invention is not limited thereto. It will be apparent to those skilled in the art that the bead coating liquid can be prepared by appropriately selecting an optically clear synthetic resin and mixing it with the glass beads in a liquid state. In order to form a liquid state, the transparent resin is dissolved by a solvent, and the amount of the solvent added is 100 to 500% by weight compared to the transparent resin. The content of glass beads may be used in an amount of 50 to 300% by weight relative to the transparent resin. When the content of the glass bead is used in less than 50% by weight, there may be a problem that the low amount of glass bead in the fixing layer of the bead is insufficient reverse reflection, if the content exceeds 300% by weight, glass bead Too high content may not be sufficiently fixed by the transparent synthetic resin, there may be a problem that separation or cracking occurs in the bead fixing layer. In the above, the leading film is coated on the bead coating solution thereon to complete the formation of the bead fixing layer and the adhesive layer after the release or release (or demoulding) can be easily separated from the product containing the bead fixing layer, if necessary The sheet may be used as a sheet, and the material may be polyethylene terephthalate and other materials such as paper, and silicon may be released to facilitate surface release.

Glass beads used in the bead fixing layer is not particularly limited, but may preferably have an average particle diameter of 30 to 80 μm and a refractive index of 1.9 or more. If the average particle diameter of the glass bead is less than 30㎛, there is a problem that the brightness performance is low, on the contrary, if the average particle diameter exceeds 80㎛ coating workability becomes difficult. In addition, when the refractive index of the glass bead is less than 1.9, deterioration in luminance performance occurs.

The bead coating liquid may further include a curing agent for curing the transparent synthetic resin constituting the bead coating liquid, the bead coating liquid mixed with the glass bead is continuously stirred even during the addition of the curing agent to separate the glass beads in the bead coating liquid and Prevent sedimentation. The curing agent may vary depending on the transparent synthetic resin constituting the bead coating solution, and the water curing agent to be used may be various, and a compound having an isocyanate group, an epoxy, an aziridine group, and the like is generally used, and these reactive groups are contained in the transparent resin. It reacts with hydroxy, amine, carboxyl groups and the like to cure into a crosslinked structure.

For example, when a polyacrylic resin is used as the transparent synthetic resin, preferably the yellowing type isocyanate may be used as the curing agent, and the polyacrylic resin and the yellowing type isocyanate curing agent are well known to those skilled in the art. It is to be understood that the present invention is so known that it can be purchased and used commercially by the manufacturers.

In the present invention, the thickness of the bead fixing layer is not particularly limited, but may be preferably 40 to 200 μm, which depends on the particle diameter of the glass beads used. That is, the bead fixation layer thickness is thicker than the maximum particle diameter of the beads used, and does not exceed three times the average particle diameter. If the thickness of the bonding layer is smaller than the maximum particle size, the coating is difficult, and when the average particle diameter is more than three times, the luminance performance is deteriorated.

The metal layer formed on one surface of the bead fixing layer is the same or similar to the metal layer used in the manufacture of the conventional retroreflective sheet, and is mainly configured to form a metal such as aluminum or silver by a deposition method to function as a reflective layer. do.

The pressure-sensitive adhesive layer formed on one surface of the metal layer is formed by the same or similar method to that used in the manufacture of a conventional retroreflective sheet, and in the present patent, a pressure-sensitive adhesive was first coated on a release liner and dried and then laminated on a metal layer. It is made by applying a pressure-sensitive adhesive used in the manufacture of a conventional retroreflective sheet to form a layer, such a pressure-sensitive adhesive can also be used by those skilled in the art to buy a commercially available pressure-sensitive adhesive, it can be coated in a conventional coating method to form a layer have. In addition, a release layer such as silicon is coated on the surface of the release liner to impart a function that can be easily peeled off from the pressure-sensitive adhesive layer.

In addition, the method of manufacturing a retroreflective sheet of the present invention, as shown in Figure 3, in the manufacture of the retroreflective sheet, (1) the bead coating liquid which is a mixture of glass beads and transparent synthetic resin on the surface of the leading film 21 Forming a bead fixed layer 11 by the coating of the bead fixed layer forming step; (2) a metal layer forming step of forming a metal layer 12 on the bead fixing layer 11; (3) an adhesive layer forming step of forming an adhesive layer 13 by coating the adhesive 132 on the release liner 131; And (4) an adhesive layer attaching step of attaching the adhesive layer 13 on the metal layer 12; Characterized in that made.

The bead fixing layer forming step of (1) is a step of forming a glass bead layer 112 for performing a reverse reflection function, the mixed solution of glass beads and transparent synthetic resin on the surface of the leading film 21 The coating consists of forming the adhering layer 11 by coating.

The metal layer forming step of (2) consists of forming the metal layer 12 on the bead fixing layer 11, wherein the metal layer 12 mainly contains aluminum or silver on the bead fixing layer 11. By vapor deposition.

The pressure-sensitive adhesive layer forming step of (3) is made by coating a conventional pressure-sensitive adhesive 132 on a conventional release liner 131, the retro-reflective sheet according to the invention functions to have a self-adhesive property.

Attaching the pressure-sensitive adhesive layer of (4) consists of attaching the formed pressure-sensitive adhesive layer 13 on the formed metal layer 12, wherein the release liner 131 is a pressure-sensitive adhesive layer 13 having a self-adhesive property Functions to maintain adhesion by protecting it from external dust.

Hereinafter, preferred embodiments and comparative examples of the present invention will be described.

The following examples are intended to illustrate the invention and should not be understood as limiting the scope of the invention.

Example  One

Polyacrylic resin was used as a transparent synthetic resin, but glass beads having a different average particle size of refractive index 2.2 of 100 g of a liquid polyacrylic resin (26% solids) dissolved in a mixed solvent containing ethyl acetate (bead1 average particle diameter 42㎛, 60 g of bead 2 average particle diameter of 50 μm was used alone or in mixture, and the glass beads were dispersed in the transparent synthetic resin, and 3 g of a yellowed isocyanate solution (75% solids) was added thereto as a curing agent. And the bead coating solution was prepared by stirring, and the mixed solution was kept stirring until coating. This bead coating solution was coated on a PET film to form a bead fixation layer of various thicknesses depending on the coating gap. Subsequently, aluminum was deposited thereon to form a metal layer having a thickness of 1.0 μm or less. Thereafter, a conventional acrylic urethane adhesive is coated on a conventional release liner to form a pressure-sensitive adhesive layer having a thickness of 40 μm, and then the pressure-sensitive adhesive layer is laminated on the metal layer coated on the bead fixing layer, thereby having a self-adhesive retroreflection. After preparing the sheet, the luminance was measured and shown in Table 2.

When the average particle diameter of the beads was 42 ㎛, the luminance was less than 50, and when 50 ㎛ was used alone, the luminance was about 80, but the variation was large according to the coating gap. However, when a smaller particle size of 42 μm was added to the particle size of 50 μm, the deviation was decreased and the overall luminance value increased, indicating a more stable and higher luminance against the process deviation.

division Prescription 1 Prescription 2 Prescription 3 Prescription 4 Acrylic resin 27.0 27.0 27.0 27.0 solvent 73.0 73.0 73.0 73.0 Hardener 3.0 3.0 3.0 3.0 Bead Average Particle Size (42㎛) 60.0 5.0 5.0 Bead Average Particle Size (50㎛) 60.0 60.0 55.0

division Prescription 1 Prescription 2 Prescription 3 Prescription 4 Acrylic resin 27.0 27.0 27.0 27.0 solvent 73.0 73.0 73.0 73.0 Hardener 3.0 3.0 3.0 3.0 Bead Average Particle Size (42㎛) 60.0 5.0 5.0 Bead Average Particle Size (50㎛) 60.0 60.0 55.0

Experimental Example  One

The luminance of the retroreflective sheet prepared according to Example 1 was measured at 0.2 / -4 ° (observation angle / incidence angle) using a luminance meter ATI 930 ratio (USA, Gamma Scientific, ART 930B), It was confirmed that the luminance can obtain a luminance of 70 Cd / lux · m 2 or more. From this, it can be seen that the sticker-type retroreflective sheet according to the present invention is sufficiently high in terms of luminance to provide a high retroreflective sheet.

In addition, the sticker-type retroreflective sheet according to the present invention can be cut using a conventional scissors or knife, and has an advantage that the adhesive layer is formed on the retroreflective sheet itself so that it can be easily attached to the surface of any object. . Therefore, the general public can easily give a retroreflective function to the object.

As described above, the present invention has an effect of providing a sticker-type retroreflective sheet and a method for manufacturing the same so that the retroreflective effect can be easily applied by cutting and attaching where retroreflection is required.

Claims (8)

A bead fixing layer, which is a surface layer formed by coating a mixture of glass beads and a transparent synthetic resin, a metal layer laminated on the bead fixing layer, a pressure-sensitive adhesive layer laminated on the metal layer, and a release liner attached on the pressure-sensitive adhesive layer It comprises, but the bead fixing layer is a retroreflective sheet comprising a glass bead, characterized in that consisting of a surface layer, a glass bead layer and a focus layer. The method of claim 1, The bead fixing layer is made by coating and drying a bead coating solution made by mixing a transparent synthetic resin and glass beads selected from the group consisting of polyacrylic resins, polyesters, polyurethanes and alkyds or mixtures thereof, wherein the bead coating solution Retroreflective sheet, characterized in that the content of the glass bead mixture in the mixture is made in an amount of 50 to 300% by weight relative to the transparent synthetic resin. The method of claim 2, Retroreflective sheet, characterized in that the glass beads have an average particle diameter of 30 to 80㎛. The method of claim 3, wherein The glass bead is retroreflective sheet, characterized in that using a mixture of two or more particle diameters. The method of claim 2, Reverse glass sheet, characterized in that the glass bead has a refractive index of 1.9 to 2.5. The method of claim 2, The bead coating sheet is a reverse-reflective sheet, characterized in that further comprises a curing agent for curing the transparent synthetic resin constituting the bead coating liquid. The method of claim 1, Retroreflective sheet, characterized in that the thickness of the fixing layer is formed 40 to 200㎛. In the manufacture of retroreflective sheeting, (1) a bead fixing layer forming step of forming a bead fixing layer by coating a bead coating liquid, which is a mixture of glass beads and a transparent synthetic resin, on the surface of the leading film (PET); (2) forming a metal layer on the bead fixing layer; (3) pressure-sensitive adhesive layer forming step of coating the pressure-sensitive adhesive on the release liner; And (4) an adhesive layer attaching step of attaching the adhesive layer on the metal layer; Method for producing a retro-reflective sheet, characterized in that consisting of.

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