KR102315443B1 - Roller for extrusion molding, manufacturing method of the same, and manufacturing method of light guding plate using the same - Google Patents

Abstract

The manufacturing method of the roller for extrusion molding comprises the steps of forming a pattern groove; forming a flat surface; determining a shape of a deviation compensator interposed between the pattern groove and the flat surface; and forming the deviation compensating portion according to the determined shape of the deviation compensating portion, wherein the determining of the shape of the deviation compensating portion includes at least a first radius defined as from the pattern groove to the axis of rotation of the extrusion roller and from the flat surface to the axis of rotation. It is determined based on the defined second radius.

Description

Roller for extrusion molding, manufacturing method thereof, and light guide plate manufacturing method using the same

The present invention relates to a roller for extrusion molding, a method for manufacturing the same, and a method for manufacturing a light guide plate using the same, and more particularly, to a roller for extrusion molding capable of manufacturing a light guide plate with reduced thickness variation, a manufacturing method thereof, and a light guide plate using the same It relates to a manufacturing method.

In general, in manufacturing the light guide plate, tapered LG manufacturing technology capable of reducing generalized light loss is used. This has the advantage of being able to mold a complex shape precisely because it can freely mold a desired shape with a manufacturing method by an injection method. However, the injection method has a limitation in that only the light guide plate with a thickness of 0.4T or more can be molded at the current level of technology. In order to overcome this limitation, the use of a light guide plate manufacturing method using a roller for extrusion molding, rather than the injection method, is being used.

An object of the present invention is to provide a roller for extrusion molding capable of manufacturing a light guide plate with reduced thickness variation, a manufacturing method thereof, and a light guide plate manufacturing method using the same. It relates to a roller for extrusion molding in which the deviation compensating part is processed as a separate part in order to compensate for the thickness deviation of the light guide part excluding the light incident part in the light guide plate made by the general extrusion roller.

A method of manufacturing a roller for extrusion molding of a light guide plate according to an embodiment of the present invention includes forming a pattern groove; forming a flat surface; determining a shape of a deviation compensator interposed between the pattern groove and the flat surface; and forming the deviation compensating unit according to the determined shape of the deviation compensating unit, wherein the determining of the shape of the deviation compensating unit includes at least a first radius defined by a rotation axis of the extrusion roller from the pattern groove and the It is characterized in that it is determined based on the second radius defined by the flat surface to the axis of rotation.

A method of manufacturing a light guide plate according to an embodiment of the present invention provides a molding roller having a side surface having a groove, a flat surface, and a deviation compensating part interposed between the groove and the flat surface to connect the groove and the flat surface to do; providing a base material to the forming roller; and passing the base material through the molding roller to form a light guide plate, wherein the forming of the light guide plate includes first compressing a first region of the base material with the groove to form a light incident portion of the light guide plate. ; and second compressing the second region of the base material with the flat surface and the deviation compensator to form a light guide portion of the light guide plate, wherein a first radius from the deviation compensator to the rotation axis is from the flat surface. It is characterized in that it is larger than the second radius to the axis of rotation.

A roller for extrusion molding according to another embodiment of the present invention includes a rotating shaft; and a side surface having a pattern groove recessed toward the rotation axis, a flat surface, and a deviation compensating unit interposed between the flat surface and the pattern groove to connect the flat surface and the pattern groove, wherein the deviation compensating unit includes the rotation shaft A first radius of to is greater than a second radius from the flat surface to the axis of rotation.

The roller for extrusion molding according to an embodiment of the present invention is interposed between the flat surface and the pattern groove and includes a side surface having a deviation compensating part connecting the flat surface and the pattern groove. Accordingly, the flat surface of the light guide plate manufactured by the extrusion roller may have an effect of reducing thickness deviation by the deviation compensating unit.

1 is a schematic view of a roller for extrusion molding according to an embodiment of the present invention.
FIG. 2 is a plan view showing a half of the roller for extrusion molding shown in FIG. 1 .
3 is a schematic diagram of a raw light guide plate manufacturing process by a roller for extrusion molding according to an embodiment of the present invention.
FIG. 4 is a cross-sectional view illustrating a process of manufacturing a raw light guide plate using the extrusion roller shown in FIG. 1 .
5 is a perspective view of a raw light guide plate made by a roller for extrusion molding according to an embodiment of the present invention.
6 is a perspective view of a light guide plate according to an embodiment of the present invention.
7A is a graph showing the thickness deviation of the light guide part according to the position of the light guide plate manufactured by the conventional extrusion roller.
7B is a graph illustrating a thickness deviation value of a light guide part according to a position of a light guide plate according to an exemplary embodiment of the present invention.

Since the present invention can have various changes and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

In describing each figure, like reference numerals have been used for like elements. In the accompanying drawings, the dimensions of the structures are enlarged than the actual size for clarity of the present invention. Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. Further, when a part of a layer, film, region, plate, etc. is said to be “on” or “on” another part, this includes not only cases where it is “directly on” another part, but also cases where another part is in between. . Conversely, when a part of a layer, film, region, plate, etc. is said to be "under" another part, this includes not only cases where it is "directly under" another part, but also cases where another part is in between.

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

1 is a schematic view of a roller for extrusion molding according to an embodiment of the present invention.

Referring to FIG. 1 , the roller 100 for extrusion molding according to an embodiment of the present invention includes a rotation shaft 103 parallel to a first direction D1 and a side surface SS.

The side surface SS includes a pattern groove 102 recessed in the direction of the rotation axis 103 , a flat surface 101 , and a deviation compensating part 104 connecting the flat surface 101 and the pattern groove 102 . include

As an example of the present invention, the roller 100 for extrusion molding has the two deviation compensating parts 104 provided on both sides of the pattern groove 102 , and the two flat surfaces 101 .

FIG. 2 is a plan view showing a half of the roller for extrusion molding shown in FIG. 1 .

FIG. 2 shows a cross section of the extrusion roller 100 cut along the cut surface including the rotation shaft 103 shown in FIG. 1, and only half of the cut roller 100 for extrusion molding is shown. did.

Hereinafter, a manufacturing method of the roller 100 for extrusion molding will be described.

The method of manufacturing the roller 100 for extrusion molding includes, for example, forming the pattern groove 102 , forming the flat surface 101 , and determining the shape of the deviation compensating part 104 . and forming the rotation shaft 103 .

As an example of the present invention, the pattern groove 102 , the flat surface 101 , and the deviation compensating part 104 may be formed by processing the side surface of the initially provided cylinder.

As shown in FIG. 2 , the pattern groove 102 formed by the step of forming the pattern groove 102 connects the groove base surface 102a and the groove base surface 102a to the deviation compensating part 104 . and an inclined surface 102b. As an example of the present invention, the groove base surface 102a is parallel to the rotation axis 103 . One end of the inclined surface 102b is connected to the groove base surface 102a. The other end of the inclined surface 102b is from one end of the inclined surface 102b. It extends at a predetermined angle with the rotation shaft 103 . The other end of the inclined surface 102b is connected to the deviation compensating part 104 . The shape of the pattern groove 102 is not limited thereto. For example, the shape of the pattern groove 102 corresponds to the shape of the original light incident part 403 (shown in FIG. 4 ) of the original light guide plate 400 (shown in FIG. 4 ), as will be described later. A distance from the groove base surface 102a to the rotation shaft 103 may be defined as a first radius r1.

The flat surface 101 formed by the step of forming the flat surface 101 is parallel to the rotation axis 103 . In addition, the distance from the flat surface 101 to the rotation shaft 103 is constant. A distance from the rotation shaft 103 to the flat surface 101 may be defined as a second radius r2.

As will be described later, the deviation compensating unit 104 includes the raw light guide part 401 (shown in FIG. 4 ) of the raw light guide plate 400 (shown in FIG. 4 ) manufactured by the extrusion roller 100 . Correct the thickness deviation.

In the step of determining the shape of the deviation compensator 104 , the shape of the cross-section of the deviation compensator 104 may be determined based on the first radius r1 and the second radius r2 . Furthermore, the shape of the deviation compensator 104 may be determined based on a difference between the first radius r1 and the second radius r2 , that is, the height PH of the pattern groove 102 . For example, a third radius r3 from the deviation compensator 104 to the rotation shaft 103 may increase as the height PH increases. In one embodiment of the present invention, the second radius r2 is greater than the first radius r1, and the third radius r3 is greater than the second radius r2. Here, the third radius r3 may be defined as the longest distance among the distances from the deviation compensator 104 to the rotation shaft 103 .

Also, the shape of the deviation compensating part 104 may be determined based on the first width w1 of the pattern groove 102 and the second width w2 of the flat surface 101 . Here, the first and second widths w1 and w2 are widths in the direction of the rotation axis 103 . For example, the third radius r3 may increase as the first width w1 increases. Also, the third radius r3 may increase as the ratio of the first width w1 divided by the third width w3 of the deviation compensating part 104 increases.

The shape of the cross section of the deviation compensator 104 may be a curve shape of a linear function or a quadratic function, and may also be a curved shape that can be expressed as a tertiary or higher-order multi-order function or a combination thereof.

In addition, the shape of the deviation compensating part 104 may be determined in consideration of the characteristics of the base material 307 (shown in FIG. 3 ) to be extruded using the extrusion roller 100 . For example, the properties of the base material 307 may include viscosity, elasticity, density, and the like of the base material 307 .

In addition, the third width w3 in a direction parallel to the first direction D1 may be formed to be 30 mm or more and 100 mm or less. In addition, the third radius r3 is generally 5 um or more and 100 u or less.

3 is a schematic diagram of a raw light guide plate manufacturing process using a roller for extrusion molding according to an embodiment of the present invention.

Referring to FIG. 3 , the extrusion apparatus includes an inlet 300 , an extruder 301 , a collection unit 303 , a base roller 305 , and the roller 100 for extrusion molding.

The inlet 300 is disposed above the extruder 301 . The base material 307 is introduced through the inlet 300 . As the base material 307, the polymer resin is generally used, but is not limited thereto.

The extruder 301 melts the base material 307 provided through the inlet 300 . More specifically, the extruder 301 rotates screws (not shown) included therein, and passes the base material 307 between the rotating screws to uniformly distribute the base material 307 . melt it The screw may be implemented as, for example, a meshing type, a rainwater type, a co-rotating type, a two-way rotating type, and the like.

The extruder 301 collects the molten base material 307 in the collecting part 303 .

The collecting part 303 is provided on the lower surface of the extruder 301 . The collecting part 303 provides the molten base material 307 downward. More specifically, the collecting part 303 provides the molten base material 307 between the base roller 305 and the extrusion roller 100 .

Unlike the roller 100 for extrusion molding, the base roller 305 is a roller having a cylindrical shape in which the pattern groove 102 or the deviation compensating part 104 does not exist.

The axis of rotation of the base roller 305 is parallel to the axis of rotation 103 of the roller 100 for extrusion molding. A roller gap RG is defined between the base roller 305 and the extrusion roller 100 along the second direction D2. The second direction D2 may be parallel to an imaginary line connecting the rotation shaft of the base roller 305 and the rotation shaft 103 of the extrusion roller 100 .

The base roller 305 rotates in a clockwise direction based on the rotation axis of the base roller 305 , and the roller 100 for extrusion molding rotates in a counterclockwise direction based on the rotation axis 103 .

The base material 307 interposed between the roller gaps RG is extruded by the rotating base roller 305 and the extrusion roller 100 . As such, the base roller 305 and the extrusion roller 100 extrude the base material 307 to form a raw light guide plate 400 (shown in FIG. 4 ).

FIG. 4 is a cross-sectional view illustrating a process of manufacturing a raw light guide plate using the extrusion roller shown in FIG. 1 .

The raw light guide plate 400 is formed while the base material 307 is interposed between the roller gaps RG, and is extruded by the rotating base roller 305 and the extrusion roller 100 .

The raw light guide plate 400 includes a raw light guide part 401 , a raw connection part 402 , and a raw light input part 403 . In addition, the raw light incident part 403 includes an upper surface 403a and a reflective surface 403b.

The raw light guide part 401 , the raw connection part 402 , and the raw light input part 403 are respectively formed to correspond to the first to third areas A1 to A3 . In detail, the first to third regions A1 to A3 may be sequentially defined along the first direction D1 , respectively, the flat surface 101 , the deviation compensating part 104 , and the It may be defined corresponding to the pattern groove (102).

The raw light guide part 401 may be formed by first compressing the base material 307 corresponding to the first area A1 onto the flat surface 101 . More specifically, as the flat surface 101 applies pressure to the outer peripheral surface of the base material 307 corresponding to the first area A1, the base material 307 corresponding to the first area A1 ) has a shape corresponding to the flat surface 101 .

The raw connection part 402 may be formed by second compressing the base material 307 corresponding to the second area A2 by the deviation compensating part 104 . More specifically, as the deviation compensator 104 applies pressure to the outer peripheral surface of the base material 307 corresponding to the second area A2, the base material corresponding to the second area A2 ( The upper surface of 307 has a shape corresponding to the deviation compensating part 104 .

The raw light incident part 403 may be formed by third compressing the base material 307 corresponding to the third area A3 into the pattern groove 102 . More specifically, as the pattern groove 102 applies pressure to the outer peripheral surface of the base material 307 corresponding to the first area A1, the base material 307 corresponding to the first area A1 ) has a shape corresponding to the upper surface of the pattern groove (102). In more detail, the upper surface 403a has a shape corresponding to the shape of the groove base surface 102a, and the reflective surface 403b has a shape corresponding to the shape of the inclined surface 102b.

The lower surface 404 of the raw light guide plate 400 may be formed by fourth compressing the base material 307 corresponding to the first to third areas A1 to A3 with the base roller 305 . More specifically, as the base roller 305 applies pressure to the outer peripheral surface of the base material 307 corresponding to the first to third areas A1 to A3, the first to third areas A1 to A3 A lower surface of the base material 307 corresponding to A3) has a flat shape corresponding to the outer peripheral surface of the base roller 305 .

5 is a perspective view of a raw light guide plate made by a roller for extrusion molding according to an embodiment of the present invention.

Referring further to FIG. 5 , the raw light guide plate 400 includes the raw light guide part 401 , the raw connection part 402 , and the raw light input part 403 as described above with reference to FIG. 4 . In addition, the raw light incident part 403 includes an upper surface 403a and the reflective surface 403b.

When viewed from the second direction D2, the shape of the cross-section of the raw connection part 402 may be a curve shape of a linear function or a quadratic function, and is also expressed as a tertiary or higher-order multi-order function and a combination thereof. It can be any possible curved shape.

In addition, when viewed from the second direction D2 , the first thickness th1 , which is the thickness of the raw light guide part 401 , is always thicker than the second thickness th2 , which is the thickness of the raw connection part 402 , and the It is thinner than the third thickness th3 which is the thickness of the original light incident part 403 .

In extrusion molding, when the same step as the pattern groove 102 is formed in the roller 100 for extrusion molding, the region between the flat surface 101 and the pattern groove 102, that is, the second region A large pressure acts on the base material 307 provided in (A2). Accordingly, after the extrusion molding is completed and the raw light guide plate 400 is formed, when a predetermined time elapses, the portion corresponding to the compressed second area A2 (the raw connection part 402) is inflated, The upper surface of the raw connector 402 protrudes upward.

6 is a perspective view of a light guide plate according to an embodiment of the present invention.

6 , when the original light guide plate 400 is cut to be bisected in the second direction D2 , two light guide plates 600 are formed.

The light guide plate 600 includes a light guide part 601 , a connection part 602 , and a light input part 603 . In addition, the light incident part 603 includes an upper surface 603a and the reflective surface 603b. A cross section of the reflective surface 603b generally has a linear shape of a linear function.

In the light guide plate 600 , when viewed along the second direction D2 , the fourth thickness th4 , which is the thickness of the light guide part 601 , and the fifth thickness th5 , which is the thickness of the connection part 602 , are The difference is. It is smaller than the difference between the first thickness th1 and the second thickness th2. In addition, based on the cross section viewed from the light guide plate 600 in the second direction D2 , the fourth thickness th4 is always thinner than the sixth thickness th6 , which is the thickness of the light incident part 603 .

In the case of the original connection part 402, when viewed along the second direction D2, the upper surface of the original connection part 402 may have a downwardly depressed shape corresponding to the shape of the deviation compensating part 104. have. In addition, the second thickness th2 is thinner than the first and third thicknesses th1 and th3.

On the other hand, in the case of the connection part 602 , when viewed along the second direction D2 , the upper surface of the connection part 602 is flat and does not sink downward. A top surface of the connection part 602 may extend in parallel from the top surface of the light guide part 601 . Accordingly, the fifth thickness th5 may be the same as the fourth thickness th4 , and may be thinner than the sixth thickness th6 .

As such, when manufacturing the light guide plate through extrusion molding, the shape of the deviation compensating part 104 of the roller 100 for extrusion molding is taken into consideration in advance of the shape in which the raw connection part 402 expands over time. , and manufacturing the raw light guide plate 400 and the light guide plate 600 using the extrusion roller 100 , the thickness deviation of the light guide plate 600 can be reduced.

A protrusion is formed between the light incident part and the light guide part of the light guide plate manufactured by the conventional extrusion roller, and thus a relatively large thickness deviation occurs. As a result, the thickness specification of the product was not satisfied. In addition, there was a problem that includes a risk of increasing the possibility of causing re-creation and staining in the patterning molding process.

7A is a graph showing the thickness deviation of the light guide part according to the position of the light guide plate manufactured by the conventional extrusion roller.

7B is a graph illustrating a thickness deviation value of a light guide part according to a position of a light guide plate according to an exemplary embodiment of the present invention.

In FIGS. 7A and 7B , the x-axis represents the position, and the y-axis represents the thickness of the light guide plate. The position of 0 on the x-axis of FIGS. 7A and 7B corresponds to the position of the light incident part.

The first graph G1 of FIG. 7A shows the thickness deviation of the light guide part in the light guide plate manufactured by the conventional extrusion roller. The maximum value of the first graph G1 is 317 μm and the minimum value is 300 μm. Therefore, the maximum thickness deviation of the light guide plate manufactured by the roller for extrusion molding according to the prior art is about 17 μm.

A second graph G2 of FIG. 7B shows a thickness deviation of the light guide part 601 in the light guide plate 600 manufactured by the extrusion roller 100 according to an embodiment of the present invention. In addition, for convenience of explanation, FIG. 7B shows the light guide plate 600 including the light guide part 601 , the connection part 602 , and the light input part 603 together. The maximum value of the second graph G2 is 323 um and the minimum value is 319 um. Therefore, the maximum thickness deviation of the light guide plate 600 manufactured by the extrusion roller 100 is about 4 μm.

As a result, it can be seen that the thickness deviation of the light guide part 601 of the light guide plate 600 manufactured by the extrusion roller 100 according to an embodiment of the present invention is reduced, and the problems listed above are solved. can be alleviated.

Although described with reference to the above embodiments, those skilled in the art can understand that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the following claims. There will be.

100: roller for extrusion molding 104: deviation compensation part
400: raw light guide plate 502: raw connection
600: light guide plate 602: connection part

Claims (9)

In the manufacturing method of the roller for extrusion molding,
forming a pattern groove;
forming a flat surface;
determining a shape of a deviation compensator interposed between the pattern groove and the flat surface; and
and forming the deviation compensating unit according to the determined shape of the deviation compensating unit, and
Determining the shape of the deviation compensating part comprises determining a third radius defined by the distance from the deviation compensating part to the rotational axis of the roller for extrusion molding,
The third radius is at least determined in proportion to a difference between a first radius defined as a distance from the pattern groove to the axis of rotation and a second radius defined as a distance from the flat surface to the axis of rotation. A method of manufacturing a dragon roller.
According to claim 1,
The determining of the shape of the deviation compensator further includes determining the third radius to be proportional to the first width of the pattern groove,
The first width is a method of manufacturing a roller for extrusion molding parallel to the axis of rotation.
According to claim 1,
The determining of the shape of the deviation compensator further includes determining the third radius to be proportional to a ratio of the first width of the pattern groove to the second width of the deviation compensator,
Each of the first width and the second width is a method of manufacturing a roller for extrusion molding parallel to the axis of rotation.
According to claim 1,
The step of determining the shape of the deviation compensating part further comprises the step of considering at least one of the viscosity, elasticity, and density of the base material to be extruded using the extrusion roller. Way.
delete providing a molding roller having a groove, a flat surface, and a side surface having a deviation compensating part interposed between the groove and the flat surface to connect the groove and the flat surface;
providing a base material to the forming roller; and
and passing the base material through the forming roller to form a light guide plate,
Forming the light guide plate comprises:
first compressing the first region of the base material with the groove to form a light incident portion of the light guide plate; and
and second compressing the second region of the base material with the flat surface and the deviation compensating part to form the light guide part of the light guide plate, wherein the first radius from the deviation compensating part to the rotation axis of the shaping roller is the A method of manufacturing a light guide plate, characterized in that it is larger than a second radius from the flat surface to the rotation axis.
axis of rotation;
A side surface having a pattern groove recessed toward the rotation axis, a flat surface, and a deviation compensating part interposed between the flat surface and the pattern groove to connect the flat surface and the pattern groove,
A first radius from the deviation compensator to the rotation shaft is larger than a second radius from the flat surface to the rotation shaft.
8. The method of claim 7,
The cross section of the deviation compensator is a multi-order function,
A roller for extrusion molding, characterized in that the distance from the flat surface to the rotation shaft is constant.
According to claim 1,
The third radius is greater than the second radius, and the second radius is greater than the first radius.

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