WO2015194800A1

WO2015194800A1 - Method for manufacturing sheet forming mold, and sheet forming mold and retroreflective sheet

Info

Publication number: WO2015194800A1
Application number: PCT/KR2015/005946
Authority: WO
Inventors: 오종민
Original assignee: 미래나노텍㈜
Priority date: 2014-06-16
Filing date: 2015-06-12
Publication date: 2015-12-23
Also published as: KR102200725B1; KR102200725B9; KR20150144053A

Abstract

The present invention relates to a method for manufacturing a sheet forming mold, and a sheet forming mold and a retroreflective sheet, and to a sheet forming mold for forming a retroreflective sheet, a method for manufacturing the sheet forming mold, and the retroreflective sheet manufactured by using the sheet forming mold. One embodiment of the present invention relates to the method for manufacturing the sheet forming mold forming a cube corner retroreflective sheet by using a flake assembly in which a plurality of flakes are aligned, comprising the steps of: preparing the flake assembly having a plurality of array lines, which are a boundary line between the adjacent flakes, by aligning the flakes such that the lateral sides of each flake come into contact with each other; forming a plurality of cube corner mold patterns having triangular pyramid shapes on the upper surface of a flake assembly array; and changing the shapes of the cube corner mold patterns on the upper surface of the array by moving at least one flake of the flake assembly in the direction of the array line.

Description

Mold manufacturing method for sheet forming and sheet forming mold and retroreflective sheet

The present invention relates to a sheet forming mold manufacturing method and a sheet forming mold and a retroreflective sheet, comprising a sheet forming mold for forming a retroreflective sheet, a method for manufacturing the same, and a retroreflective sheet manufactured using the sheet forming mold. It is about.

The retroreflective sheet can reflect incident light on the main surface of the sheet in the same direction as the incident direction. Because of this unique feature, retroreflective sheets have been used extensively for a wide variety of identifiable applications involving traffic and personal safety signs. Examples of typical uses of retroreflective sheets include the placement of retroreflective sheets on road signs, traffic cones, and barricades that specifically enhance discrimination under poor lighting conditions such as night driving conditions or in inclement weather conditions. Can be.

The retroreflective sheet has a structured surface that includes one or more cube corner pattern arrangements that enhance the visibility of the object. Typically, a cube corner retroreflective sheet is formed as an array of interconnected hard, cube corner patterns that retroreflect incident light on the sheet major surface. The basic cube corner pattern known in the art related to retroreflective is a tetrahedral structure having three sides intersecting at the cube vertices (vertical vertices) and a triangular bottom face as shown in FIG. 1. The optical axis (optical axis) of the cube corner pattern is a line extending from the cube vertex to the center point of the bottom surface, and refers to an axis extending from the cube vertex and dividing the internal space of the cube corner pattern into three parts. Light incident on the bottom surface of the cube corner pattern is reflected from each of the three sides of the pattern and returns as reflected light in the same direction as the incident direction.

The triangle on each side of the cube corner pattern of the triangular pyramid of the cube corner type retroreflective sheet has both a region where no retroreflection occurs and a region where the retroreflection occurs. The cube corner pattern formed by the effective area where the retroreflection occurs may be formed into various cube corner patterns depending on how the effective area is cut. For example, the size or shape of the effective retroreflective area may vary depending on the shape of the cube corner pattern.

Also, cube corner patterns typically exhibit the highest optical efficiency for light incident on the bottom surface of these cube corner patterns almost along the optical axis. The amount of light retroreflected by the cube corner retroreflective sheet decreases as the incident angle deviates from the optical axis. For example, light incident at a large angle of incidence of about 85 degrees or more with respect to an axis perpendicular to the bottom surface of the cube corner type retroreflective sheet is usually close to the bottom surface, so that the retroreflectivity is low and from about 30 degrees to the bottom surface of the retroreflective sheet. Since light incident at a small angle of incidence in the range of 40 degrees is close to the optical axis, the retroreflectivity of incident light is high.

The maximum retroreflective efficiency of the cube corner retroreflective sheet is related to the shape of the cube corner pattern on the structured surface of the retroreflective sheet. Therefore, if the shape of the cube corner pattern is deformed, it may correspondingly cause distortion of the optical properties of the cube corner retroreflective sheet. In order to suppress such undesired physical deformation, the cube corner pattern of the retroreflective sheet is made of a material having a relatively high elastic modulus sufficient to suppress the physical deformation of the cube corner pattern during bending or elastic extension of the sheet. is average. As mentioned above, the retroreflective sheeting is flexible enough to be able to attach to the curved or flexible base itself, or to be wound onto a roll to facilitate storage and transportation. It is often desirable. Traditionally, either the negative image of the desired cube corner pattern shape (the concave-convex shape opposite to the concave-convex shape of the cube corner element) or the positive image (the convex shape same as the concave-convex shape of the cube corner element) The master mold (master mold) containing is produced first, and a retroreflective sheet is manufactured.

A mold for forming a cube corner type retroreflective sheet can be produced as a molded object obtained by replicating a master mold by nickel electroplating, chemical vapor deposition, or physical vapor deposition.

Various processes for forming a mold for forming a cube corner retroreflective sheet used to make a cube corner retroreflective sheet are presented. Among them, in the case of Korean Patent No. 10-0574610, a mold for forming a sheet is manufactured using a plurality of flakes.

In detail, as shown in FIG. 2, a lamella assembly 100 composed of a plurality of flakes 10 is provided, and three side surfaces are provided on a processing surface of some or all of the plurality of flakes 10: 10a to 10f. A plurality of mold patterns P (cube corner mold patterns) in the form of a triangular pyramid are formed. 3, one or more flakes 10 are removed from the flakes 10 of the flake assembly 100, thereby changing the shape of the structured surface of the machined surface. Therefore, the ratio of the effective area to which retroreflection is made is improved.

That is, referring to FIG. 4, which is a plan view of the machining surface of FIG. 2 from above, the effective area (dotted area) in which retroreflection is made is the first foil 10a, the third foil 10c, and the fourth foil 10d. ) And the sixth thin film 10f, etc., may reduce the retroreflective efficiency. Accordingly, as shown in FIG. 4, the second flakes 10b, the fifth flakes 10e, and the like of the flake assembly 100 having an ineffective area are removed, and the remaining flakes are the first flakes 10a and the third flakes 10c. By attaching the fourth piece 10d to each other, the effective area for retroreflective reflection can be increased as shown in FIG. 5 to increase the retroreflective efficiency.

However, in the case of removing a portion of the flake 10 and manufacturing a mold for forming a sheet, a process of processing a cube corner mold pattern also for the second flake 10b, the fifth flake 10e, etc., which should be finally removed. There is a problem of inefficiency. In addition, there is a problem of inefficiency of manufacturing costs because the flakes (10b, 10e) to be removed are not used and must be disposed of.

Prior Art Documents: Korean Patent Registration 10-0574610

The technical problem of the present invention is to further secure an effective area for causing retroreflection. Another object of the present invention is to provide a mold for forming a sheet capable of improving the retroreflective efficiency of the retroreflective sheet. In addition, the technical problem of the present invention is to reduce the manufacturing cost in manufacturing the mold for sheet molding.

Embodiment of this invention is a manufacturing method of the sheet | seat shaping | molding mold which shape | molds a cube corner type retroreflective sheet | seat using the flake assembly which arranged the plurality of flakes, Comprising: It is arrange | positioned so that the side surface of each flake may contact each other, Providing a flake assembly having a plurality of array lines that are boundary lines; Forming a plurality of cube corner mold patterns in the form of a triangular pyramid on an upper surface of the array of flake assemblies; And moving the one or more flakes of the lamella assembly in the direction of the array line to change the shape of the cube corner mold pattern on the array top surface.

In the process of forming a plurality of triangular pyramid-shaped cube corner mold patterns, the adjacent first cube corner mold pattern and the second cube corner mold pattern are formed to be adjacent as one common side.

The common side is formed at right angles to the array line of the lamella assembly.

The process of forming a plurality of triangular pyramid-shaped cube corner mold patterns, when the bottom surface of the cube corner mold pattern is a triangle of the first square, the second square and the third square, traversing the array line of the lamella assembly Forming a first groove line and a second groove line which are intersected so as to form a first angle of the cube corner mold pattern on the upper surface of the array; Forming a third groove line intersecting the first groove line to have a second angle of the cube corner mold pattern, and having a third groove line intersected with the second groove line to have a third angle of the cube corner mold pattern. Process;

The third groove line is formed at right angles to the array line of the lamella assembly.

In the process of forming a plurality of triangular pyramid-shaped cube corner mold patterns, the first flakes, the second flakes, and the third flakes are sequentially arranged in the lamella assembly, and each cube corner mold pattern includes three vertices and three vertices. The first cube corner mold pattern and the second cube corner mold pattern are formed on the array top surface across the first flakes, the second flakes, and the third flakes in the form of a triangular pyramid having a vertex connected to each other.

The first flake may include a 1A non-effective area including a 1-1 vertex of the first cube corner mold pattern and a 1-1 non-effective area and a 2-1 vertex of the second cube corner mold pattern. A second effective area including a second A non-effective area, wherein the second flake includes a first-second vertex of the first cube corner mold pattern and a first effective area in which retroreflection occurs, and a second of the second cube corner mold pattern A second effective area in which retroreflective occurs, including a second vertex, wherein the third lamella comprises a first B non-effective area in which retroreflective occurs, including the first to third vertices of the first cube corner mold pattern, And a second B-effective area in which retroreflection does not occur, including the second to third vertices of the second cube corner mold pattern.

Moving the one or more flakes of the lamella assembly in the direction of the alignment line comprises: a second having a first effective area in the first cube corner mold pattern and a second effective area in the second cube corner mold pattern The flakes are moved in the direction of the alignment line.

The movement of the second flakes may include moving the second flakes by the tangential length between the total area of the first effective area and the second effective area and the total area of the first A invalid area and the second A invalid area. To move in the direction of

The retroreflective sheet production method of the present invention comprises the steps of: providing a sheet molding mold manufactured by a sheet molding mold manufacturing method produced by an embodiment of the present invention; And forming a retroreflective sheet which is a molded object by the sheet forming mold.

Sheet molding mold which is embodiment of this invention, Bottom surface; And a structural screen formed on the opposite side of the bottom surface, wherein the structural screen includes a plurality of truncated cube corner mold patterns and a triangular pyramidal cube corner mold pattern.

The truncated cube corner mold pattern is formed such that the adjacent first truncated cube corner mold pattern and the second truncated cube corner mold pattern are adjacent as one first common edge.

The triangular pyramidal cube corner mold pattern is formed such that adjacent first triangular pyramidal cube corner mold patterns and second triangular pyramidal cube corner mold patterns are adjacent as one second common edge.

According to the embodiment of the present invention, the retroreflective efficiency of the retroreflective sheet can be improved through the movement of the flakes in manufacturing the sheet forming mold using the flake assembly. Moreover, according to embodiment of this invention, the effective area which causes reflex reflection by the movement of a flake can be ensured further. In addition, according to an embodiment of the present invention by using only by moving without removing the flakes in the lamella assembly, it is possible to reduce the manufacturing cost.

1 is a view showing a state in which the incidence angle and the reflection angle in the cube corner is the same.

2 is a perspective view of a flake assembly conventionally composed of a plurality of flakes.

3 is a view showing a state of removing the flakes having an ineffective area in the flake assembly in the prior art.

4 is a diagram showing an arrangement top surface of a lamella assembly prior to removing a lamella having a conventional non-effective area.

FIG. 5 is a diagram illustrating an arrangement top surface of a lamella assembly after removing a lamella having an ineffective area.

6 is a flowchart illustrating a mold manufacturing process for forming a sheet according to an embodiment of the present invention.

7 is a front view and a perspective view showing a lamella according to an embodiment of the present invention.

8 is a perspective view illustrating a lamella assembly in which a plurality of flakes are arranged according to an embodiment of the present invention.

9 is a view showing a state in which a plurality of triangular pyramid-shaped cube corner mold pattern is formed on the lamella assembly according to an embodiment of the present invention.

FIG. 10 is a diagram illustrating an arrangement top surface of a lamella assembly after forming a cube corner mold pattern in the form of a plurality of triangular pyramids according to an embodiment of the present invention.

11 is a diagram showing an effective area and an invalid area before moving a lamella according to an embodiment of the present invention.

12 is a diagram illustrating a state in which one or more flakes are moved in the direction of the alignment line according to an embodiment of the present invention.

FIG. 13 is a diagram showing the top arrangement surface of the lamella assembly after lamella movement in accordance with an embodiment of the present invention. FIG.

FIG. 14 is a diagram illustrating a top arrangement surface of the lamella assembly showing a state in which an effective area in which retroreflective reflection is made by the movement of the lamella according to an embodiment of the present invention is additionally formed.

15 is a cross-sectional view after the movement of the lamella in accordance with an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. BRIEF DESCRIPTION OF THE DRAWINGS The drawings may be exaggerated or enlarged for purposes of understanding, and like reference numerals designate like elements in the drawings.

6 is a flowchart showing a sheet forming mold manufacturing process according to an embodiment of the present invention, Figure 7 is a front view and a perspective view showing a flake according to an embodiment of the present invention, Figure 8 is an embodiment of the present invention 9 is a perspective view illustrating a flake assembly in which a plurality of flakes is arranged, and FIG. 9 is a view illustrating a cube corner mold pattern having a plurality of triangular pyramid shapes formed on a flake assembly according to an embodiment of the present invention. Is a diagram showing the arrangement top surface of the lamella assembly after forming a plurality of triangular pyramid-shaped cube corner mold pattern according to an embodiment of the present invention.

The present invention can produce a sheet forming mold for molding a cube corner type retroreflective sheeting using the lamella assembly 100 in which a plurality of flakes 10 are arranged.

To this end, first, the side surfaces of each lamella 10 are arranged to touch each other, to provide a lamella assembly 100 having a plurality of array lines (L1, L2, L3) which is a boundary line between adjacent flakes (S610).

Herein, laminae (10) refers to four

sides

12, 14, 20, and 22 connecting the upper surface 16, the lower surface 18, the upper surface 16 and the lower surface 18. The branch refers to a right-sided polyhedron, and the upper surface 16 is a region corresponding to the processing surface on which the mold pattern is processed. The four sides connecting the upper surface 16 and the lower surface 18 are composed of two arrangement surfaces 12 and 14 and two

end surfaces

20 and 22.

In detail, the flake 10 includes a first array surface 12 and a second array surface 14 on the opposite side thereof. In addition, the lamella 10 includes an upper surface 16 between the first and second array surfaces 12 and 14 and a lower surface 18 on the opposite side thereof. The lamella 10 includes a first end face 20 and a second end face 22 on the opposite side. In a preferred embodiment, the lamella 10 is a rectangular polyhedron whose opposing faces are substantially parallel. However, it is not necessary to limit that the opposing faces of the lamella 10 must be parallel.

In addition, for convenience of explanation, the flake 10 can also be expressed in three-dimensional spatial characteristics by superimposing the Cartesian coordinate system on the structure. The first reference plane 24 is located at the center between the alignment surfaces 12, 14. The first reference plane 24, also called the x-z plane, has a y-axis as a normal vector. The second reference plane 26, also called the x-y plane, extends substantially coplanar with the top surface 16 of the lamella 10 and has a z-axis as a normal vector. A third reference plane 28 called the y-z plane is located at the center between the first end face 20 and the second end face 22 and has the x axis as a normal vector. For the sake of clarity, various geometrical characteristics of the embodiments are described with reference to the Cartesian coordinate planes described above. However, it should be understood that such geometrical characteristics may be described using other coordinate systems or based on the structure of the lamella 10.

The lamella 10 may be formed of a material having dimensional stability that can maintain close tolerances. The lamella 10 may be made from a variety of materials, such as cuttable plastics (eg, polyethylene terephthalate, polymethyl methacrylate, and polycarbonate) and metals including brass, nickel, copper, and aluminum. The physical dimensions of the lamella 10 are mainly limited by the cutting limits. The flakes 10 preferably have a thickness of at least 0.1 mm, a height of 5.0 mm to 100.0 mm, and a width of 10 mm to 500 mm. However, this measure is only illustrative.

Using the plurality of flakes 10 to prepare the lamella assembly 100 is arranged so that the array surface of the side of the adjacent lamella 10 is in contact with each other. That is, the plurality of flakes 10a to 10n are assembled together so that the first array surface 12 of one flake 10 contacts the second array surface 14 of the adjacent flake 10. It is preferable that the plurality of flakes 10 is assembled by a fixture capable of fixing the plurality of flakes 10 adjacent to each other. Such jig can be used a variety of known jig, the detail structure of the jig is not critical to the present invention.

The lamella assembly 100 consisting of a plurality of flakes 10 will have a plurality of array lines, which are lines between the sides of adjacent flakes 10. This arrangement line is thus parallel to the first reference plane 24. For reference, the plurality of flakes 10; 10a to 10n may have their respective upper surfaces 16 substantially in the same plane. In addition, the arrangement coupling of the plurality of flakes 10 causes the array top surface 106, which is the top surface of the lamella assembly 100, to be parallel to the second reference plane 26. The array top surface 106 of the lamella assembly 100 corresponds to the surface to which the top surfaces of the plurality of flakes 10 are coupled.

On the other hand, after providing the lamella assembly 100 is arranged and fixed to the plurality of flakes, the array top surface 106 of the plurality of flakes 10 in a state of being fixed in the form of the lamella assembly 100 arranged the plurality of flakes 10 9, a plurality of cube corner mold patterns 200 having a triangular pyramid shape are formed (S620). That is, each cube corner mold pattern 200 preferably extends over the top surface of the two or more flakes 10.

The cube corner mold pattern 200 is a pattern of the mold which cuts out the cube corner pattern of the retroreflective sheet which is a to-be-molded body. The cube corner is a tetrahedral structure that reflects light in the incidence direction regardless of the light incidence direction as shown in FIG. 1, and has three sides intersecting at the vertices of the triangular pyramid and a triangular bottom surface facing the vertex. It is a tetrahedral structure in the form of a triangular pyramid. Therefore, the cube corner mold pattern 200 has a three-dimensional tetrahedral pattern in the form of a triangular pyramid.

An embodiment of the present invention is formed to have one common side between adjacent cube corner mold pattern 200. Reference is made to FIG. 10 which illustrates an array top surface of a lamella assembly after forming a plurality of triangular pyramid-shaped cube corner mold patterns 200. For convenience of description, the first cube corner mold pattern 210 and the second cube corner mold pattern 220 are shown as thick lines, but are not different from other cube corner mold patterns.

That is, the first cube corner mold pattern 210 and the second cube corner mold pattern 220 are formed to be adjacent to each other, and one side of the bottom surface of the first cube corner mold pattern 210 and the second cube corner mold pattern 220 are formed. The first cube corner mold pattern 210 and the second cube corner mold pattern 220 are formed to be adjacent to each other so that one side of the bottom surface of the bottom surface thereof is common to each other. This common side is to be formed at right angles to the array lines (L; L1, L2, L3) of the lamella assembly 100. That is, the common side is formed in the Y direction perpendicular to the array line L in the X direction.

For example, with the first flake 10a, the second flake 10b, the third flake 10c and the fourth flake 10d arranged in sequence in the lamella assembly 100, the adjacent first cube corner molds The pattern 210 and the second cube corner mold pattern 220 may be formed on the array top surface 106 across the first lamella 10a, the second lamella 10b, and the third lamella 10c. In this case, the common side between the first cube corner mold pattern 210 and the second cube corner mold pattern 220 may include a first array line L1 that is a boundary between the first foil 10a and the second foil 10b, It may be formed in a direction perpendicular to the second array line (L2) that is the boundary between the second flake 10b and the third flake 10c.

On the other hand, forming the cube corner mold pattern 200 in the form of a triangular pyramid can be formed by intersecting the 'V' shaped groove line on the array top surface 106. That is, when the bottom surface of the cube corner mold pattern 200 is a triangle having a first angle α, a second angle β and a third angle γ, first, an array line of the lamella assembly 100 is formed. A first groove line 111 and a second groove having a 'V' shape intersecting and intersecting to form the first angle α of the cube corner mold pattern 200 on the upper surface 106 of the array 106. Line 112 is formed. For reference, it has a triangular pyramid that is a cube corner mold pattern 200, and the bottom surface of the triangular pyramid is formed as a first square angle α, a second square angle β, and a third square angle γ as a triangle. The first angle α, the second angle β, and the third angle γ may have the same angle and may have different angles.

After the first groove line 111 and the second groove line 112 having the first site angle α and intersecting the first groove line 111 and the second groove line 112 are formed on the array top surface 106, the second site angle of the cube corner mold pattern 200 is formed. The third groove line 113 is formed to cross the first groove line 111 and the second groove line 112 on the arrangement upper surface 106 so as to form β) and the third site angle γ. That is, the third corner of the cube corner mold pattern 200 intersects with the first groove line 111 that is cut in a 'V' shape to have the second corner angle β of the cube corner mold pattern 200. The third groove line 113 is formed to be dug in the 'V' shape to cross the second groove line 112 to have a (γ). A plurality of third groove lines 113 having a substantially V-shape are formed along an axis substantially parallel to the axes on which each common side shown in FIG. 10 extends, preferably an axis coaxial with the axes. do. For example, the third groove line 113 of the first cube corner mold pattern 210 is formed at right angles to each of the array lines L of the lamella assembly 100, so that the adjacent second cube corner mold patterns 220 are common to each other. It will act as a side.

For reference, the V-shaped first groove line 111, the second groove line 112, and the third groove line 113 are preferably formed using appropriate material removal techniques. It is formed by removing a portion of the array top surface of the plurality of lamella assemblies 100 using suitable material removal techniques. In the present invention, the use of various material removal techniques, including precision cutting techniques such as milling, ruling and fly-cutting, can be used. Alternatively, the groove line may be formed by chemical etching or laser ablation. According to one embodiment, a diamond cutting tool having an included angle of 84.946 ° may be formed by a high precision cutting operation that repeatedly moves across the array top surface 106 of the plurality of lamella assemblies 100. Can be.

When the first groove line 111, the second groove line 112, and the third groove line 113 are formed, a repeating pattern of triangular pyramids having a tetrahedron pyramidal structure is formed on the upper surface 106 of the lamella assembly. A structural screen is formed that includes. The first groove line 111 and the second groove line 112 are formed to cross the common side of the triangular pyramid, and form an inner back angle substantially perpendicular thereto. In cube corner retroreflective techniques, the relationship between these surfaces is generally referred to as a "vertical relationship to each other." The term "aproximately mutually perpendicular" or "substantially mutually perpendicular" is used to describe a retroreflected light as described in US Patent No. 4,775,219 to Appeldorn et al. The term is commonly used to mean that it can deviate slightly from the perfect orthogonality that is useful for altering the distribution. Importantly, the surface of the triangular pyramid extends across at least a portion of the machining surface of the three flakes 10. In particular, the first surface and the second surface of the triangular pyramid intersect the first array line L1, and the third and fourth surfaces intersect the second array line L2.

On the other hand, it is possible to manufacture the cube corner mold pattern 200 of various shapes by changing the position and angle of the angle of the first groove line 111, the second groove line 112 and the third groove line 113. . Therefore, by changing the position and angle of the angle of the first groove line 111, the second groove line 112 and the third groove line 113 so as to have an effective area where reflex reflection occurs for each flake 10, or recursion It can be made to have an effective area where reflection does not occur. For example, one flake 10 may include an effective area where reflex reflection occurs and another flake 10 may include an invalid area where reflex reflection occurs.

It demonstrates with FIG. 11 which shows the effective area and the invalid area before moving a flake | flake. In FIG. 11, the dotted area is the effective area of the target area where the retroreflection occurs, and the non-dotted area is the effective area of the target area where the retroreflection does not occur. In practice, reflex reflection does not occur 100% even in ineffective area, but for convenience of explanation, it is described as an area where reflex reflection does not occur.

For convenience of description, the first cube corner mold in a state in which the first flake 10a, the second flake 10b, the third flake 10c and the fourth flake 10d are sequentially arranged in the lamella assembly 100. The pattern 210 and the second cube corner mold pattern 220 are arranged on the top surface 106 of the lamella assembly 100 across the first lamella 10a, the second lamella 10b, and the third lamella 10c. Assume that each of the phases is formed. Accordingly, the first cube corner mold pattern 210 is formed across the first foil 10a, the second foil 10b, and the third foil 10c, and likewise, the second cube corner mold pattern 220 may be formed in the first shape. It may be formed across the flake 10a, the second flake 10b, the third flake 10c.

At this time, each cube corner mold pattern 200 has a triangular pyramid consisting of three vertices and vertices connected to the three vertices. Accordingly, in the first cube corner mold pattern 210, one vertex 211 (hereinafter referred to as 'first-first vertex') is positioned on the first foil 10a and the other vertex 212 on the second foil 10b. ; 1st-2nd vertex) is located, and the other vertex 213 (hereinafter, 1st-3rd vertex) is located at the third foil 10c. Similarly, in the second cube corner mold pattern 220, one vertex 221 (hereinafter referred to as 'second-1 vertex') is positioned on the first foil 10a and another vertex (2 vertex) is formed on the second foil 10b. 222; or less, 'second-2 vertex'), and the other vertex 223 (hereinafter, 'third or third vertex') is located on the third foil 10c.

The first cube corner mold pattern 210 and the second cube corner mold pattern 220 may have effective areas and recursions where recursive reflection occurs according to positions and angles of the first groove line 111 to the third groove line 113. It has an ineffective area where reflection does not occur. The effective area and the ineffective area are along the positions and angles of the first groove line 111 to the third groove line 113. The first foil 10a, the second foil 10b, the third foil 10c and It is formed in the fourth foil 10c.

According to an embodiment of the present invention, the first foil 10a includes a first-first vertex 211 of the first cube corner mold pattern 210, and includes a first A non-effective area and a second cube in which no retroreflection occurs. Including the second-first vertex 221 of the corner mold pattern 220 to have a second effective area 2A of which no retroreflection occurs. For reference, the first foil 10a may have only an invalid area when limited to the first cube corner mold pattern 210 and the second cube corner mold pattern 220, but may be expanded to another cube corner mold pattern 200. If so, the effective area of the cube corner mold pattern 200 exists.

In addition, the second foil 10b includes a first-second vertex 212 of the first cube corner mold pattern 210 and includes a first effective area 1C and a second cube corner mold pattern 220 in which retroreflection occurs. It has a second effective area (2C) that the retroreflection occurs, including the 2-2 vertex (222) of the ().

Lastly, the third foil 10c includes the first-three vertices 213 of the first cube corner mold pattern 210, and includes a first B effective area 1B and a second cube corner mold in which retroreflection does not occur. The second third vertex 223 of the pattern 220 may be included to have a second effective area 2B of which no retroreflection occurs.

Meanwhile, as described above, the first groove line 111, the second groove line 112, and the third groove line 113 having a 'V' shape are formed on the upper surface 106 of the lamella assembly 100. Then, after uniformly forming the plurality of cube corner mold patterns 200 in the form of an array, one or more lamellas 10 of the lamella assembly 100 are moved in the direction of the array line, as shown in FIG. The shape of the cube corner mold pattern 200 on the array top surface 106 is changed. In order to increase the effective area in which retroreflection occurs by moving a portion of the flakes 10 along the array line direction (X-axis direction) among the flakes 10 constituting the flake assembly 100 to minimize the effective area. to be. For reference, FIG. 12 illustrates a state before movement. When any one or more flakes are moved along a direction parallel to the alignment line, the moved flakes will protrude from the cross section. By moving, the protruding portion of the flake is cut so that the cross section has a plane.

For example, the first cube mold pattern is formed across the first lamella 10a, the second lamella 10b, and the third lamella 10c to form a first effective area only in the second lamella 10b. It is assumed that the second cube mold pattern is formed across the first foil 10a, the second foil 10b, and the third foil 10c to form a second effective area only in the second foil 10b. In this case, only the second foil 10b having the first effective area 1C in the first cube corner mold pattern 210 and the second effective area 2C in the second cube corner mold pattern 220 is provided. Move in the direction of the array line.

As shown in FIG. 11, the movement of the 2nd flake 10b has the total area of 1st effective area 1C and the 1st

effective area

1C, 1A

non-effective area

1A, and 2A non-effective area. The second foil 10b is moved in the direction of the array line by the tangent length K between the entire areas of 2A. Only with this movement amount, the effective areas between adjacent flakes 10 are in contact with each other, and the ineffective areas are in contact with each other. FIG. 13 is a view showing the top arrangement surface of the lamella assembly 100 after the movement of the second lamella 10b and the fourth lamella 10d. 13 after the movement of the lamella 10 is compared with FIGS. 11 and 12 before the movement of the lamella 10, the second lamella 10b adjacent to the effective area of the first lamella 10a after the movement of the lamella 10 has occurred. It can be seen that the effective area of) is in contact with, and the ineffective area of the second flake 10b adjacent to the ineffective area of the first flake 10a.

In particular, the triangular pyramid is again formed in the ineffective area after the movement, and additionally has an effective area in which retroreflection is performed as shown in FIG. 14. Accordingly, it can be seen that the effective area (hatched area) of FIG. 14 after the movement is further increased as compared with the effective area (dotted area) of FIG. 11 before the movement. Therefore, the retroreflective efficiency can be improved.

As a result, the sheet forming mold produced by the manufacturing method of the present invention includes a bottom surface and a structure screen formed on the opposite side of the bottom surface, and such a structure surface is shown in FIG. Similarly, the lateral truncated cube corner mold pattern P1 having vertices a1, a2, a3, a4, a5, a6 as the original effective area, and vertices b1, b2, b3, b4. The triangular pyramidal cube corner mold pattern P2 is included in plurality.

Here, the truncated cube corner mold pattern P1 is a shape in which a part of the truncated cube corner mold pattern P1 is cut in a vertical direction in a lateral direction (horizontal direction, XY direction) rather than in the form of a complete triangular pyramid. That is, the truncated cube corner mold pattern P1 refers to a mold pattern in which an invalid area portion including some vertices, which are not in the form of a complete triangular pyramid, is cut and has only an effective area (point area). In addition, the triangular pyramidal cube corner mold pattern P2 is a pattern having a triangular pyramid including a new effective area (hatched area) in addition to the non-effective area due to the movement of the lamella 10.

Therefore, the truncated cube corner mold pattern P1 is formed such that the adjacent first truncated cube corner mold pattern and the second truncated cube corner mold pattern are adjacent through one first common edge. Further, the triangular pyramidal cube corner mold pattern P2 is formed such that adjacent first triangular pyramidal cube corner mold patterns and second triangular pyramidal cube corner mold patterns are adjacent through one second common edge.

For reference, Figure 15 (a) is a view showing a cross-sectional view of the G-G 'direction after the movement according to an embodiment of the present invention, Figure 15 (b) is a view of the HH' direction after the movement according to an embodiment of the present invention It is a figure showing a cross section

Referring to FIG. 15 (a), it can be seen that a truncated cube corner mold pattern P1 is formed. Referring to FIG. 15 (b), a triangular pyramidal cube corner mold pattern P2 is newly formed, and as a whole, It can be seen that the effective area for retroreflection is increased.

On the other hand, in the present embodiment, the sheet molding mold utilized a lamella assembly consisting of a plurality of flakes, but is not limited thereto. For example, the sheet forming mold forms an array of a plurality of cube corner mold patterns on an upper surface of one polyhedron, and then cuts several times in a direction parallel to the first reference plane to form a plurality of flakes. It can also be implemented by moving parts of the flakes.

Meanwhile, the retroreflective sheet which is a molded object including a plurality of truncated cube corner patterns and triangular pyramidal cube corner patterns can be manufactured by the sheet forming mold manufacturing method manufactured by the embodiment of the present invention. That is, the sheet molding mold manufactured by the sheet manufacturing mold manufacturing method which is an Example of this invention is provided. And the retroreflective sheet which is a to-be-molded object which contains a plurality of truncated cube corner pattern and a triangular pyramidal cube corner pattern can be manufactured by shape | molding the retroreflective sheet which is a to-be-molded object with the provided sheet shaping | molding mold.

Although the invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the invention is not limited thereto, but is defined by the claims that follow. Accordingly, one of ordinary skill in the art may variously modify and modify the present invention without departing from the spirit of the following claims.

Claims

In the manufacturing method of the sheet | seat shaping | molding mold which shape | molds a cube corner type retroreflective sheeting using the flake assembly which arranged several flakes,

Preparing a lamella assembly having a plurality of array lines, the side surfaces of each of the flakes being in contact with each other, the boundary line between adjacent flakes;

Forming a plurality of cube corner mold patterns in the form of a triangular pyramid on an upper surface of the array of flake assemblies; And

Moving one or more flakes of the lamella assembly in the direction of the array line to change the shape of the cube corner mold pattern on the array top surface;

Sheet molding mold manufacturing method comprising a.
The process of claim 1, wherein the forming of the triangular pyramid-shaped cube corner mold pattern is provided in plural.

And forming adjacent ones of the first cube corner mold pattern and the second cube corner mold pattern to be adjacent to each other through one common side.
The method according to claim 2,

And forming the common side at right angles to the array line of the lamella assembly.
The process of claim 2, wherein the forming of the triangular pyramid-shaped cube corner mold pattern is provided in plural.

When the bottom surface of the cube corner mold pattern is a triangle consisting of first, second and third angles, the first angle of the cube corner mold pattern on the top surface of the array is crossed across the array line of the lamella assembly. Forming a first groove line and a second groove line which are intersected to form a groove; And

Forming a third groove line intersecting the first groove line to have a second angle of the cube corner mold pattern, and having a third groove line intersected with the second groove line to have a third angle of the cube corner mold pattern. process;

Sheet molding mold manufacturing method comprising a.
The method according to claim 4, wherein the third groove line is formed at right angles to the array line of the lamella assembly.
The process of claim 2, wherein the forming of the triangular pyramid-shaped cube corner mold pattern is provided in plural.

When the first flakes, the second flakes, and the third flakes are arranged in sequence in the lamella assembly, each cube corner mold pattern has a triangular pyramid shape having three vertices and vertices connected to the three vertices.

And a first cube corner mold pattern and a second cube corner mold pattern are formed on the array top surface across the first, second, and third foils.
The method according to claim 6,

The first flake may include a 1A non-effective area including a 1-1 vertex of the first cube corner mold pattern and a 1-1 non-effective area and a 2-1 vertex of the second cube corner mold pattern. Includes a 2A non-effective area that does not occur,

The second flake may include a first effective area in which retroreflection occurs including the first-second vertex of the first cube corner mold pattern, and a second retroreflection including the second-second vertex of the second cube corner mold pattern. Includes 2 effective areas,

The third flake may include a first B-effective area in which no retroreflection occurs, including the first-three vertices of the first cube corner mold pattern, and the second-three vertices of the second cube corner mold pattern. A method for producing a mold for forming a sheet, comprising a second B-effective area which does not occur.
The process of claim 7 wherein the step of moving the one or more flakes of the lamella assembly in the direction of the alignment line,

And a second flake having a first effective area in the first cube corner mold pattern and a second effective area in the second cube corner mold pattern in the direction of the alignment line.
The method of claim 8, wherein the movement of the second foil,

A sheet forming mold for moving the second lamella in the direction of the alignment line by the tangential length between the total area of the first effective area and the second effective area and the total area of the first A invalid area and the second A invalid area. Manufacturing method.
Providing a sheet forming mold manufactured by the method for manufacturing a sheet forming mold according to any one of claims 1 to 9; And

Molding a retroreflective sheet that is a molded object by the sheet molding mold;

Retroreflective sheet production method comprising a.
Bottom surface;

It includes a structural screen formed on the opposite side of the bottom surface,

The structure screen is a sheet forming mold comprising a plurality of truncated cube corner mold pattern and triangular pyramidal cube corner mold pattern.
The method of claim 11, wherein the truncated cube corner mold pattern,

A sheet forming mold, wherein adjacent first truncated cube corner mold patterns and second truncated cube corner mold patterns are adjacent to each other through one first common edge.
The method according to claim 11, wherein the triangular pyramidal cube corner mold pattern,

A sheet forming mold, wherein adjacent first triangular pyramid cube corner mold patterns and second triangular pyramidal cube corner mold patterns are adjacent to each other through one second common edge.
The retroreflective sheet manufactured by the sheet forming mold of any one of Claims 11-13 which is a to-be-molded object containing a plurality of truncated cube corner patterns and a triangular pyramidal cube corner pattern.