KR20200121976A - The producing methodology of precise mould and high precise injection products - Google Patents

Abstract

The present invention relates to a micro-mold system for manufacturing an ultracompact high-precision part having a multi-scaled molding surface, and a method for manufacturing an ultracompact high-precision part using the same. The micro-mold system is used for manufacturing an ultracompact high-precision part through an injection molding process, is provided with a molding surface having fine irregularities, includes at least two types of base molds each having a different height from the bottom to the molding surface, and provides a multi-scaled molding surface having a first scale of a multi-step structure in combination with a second scale of a fine irregularity structure.

Description

Precision mold manufacturing method and ultra-precision injection molding method {THE PRODUCING METHODOLOGY OF PRECISE MOULD AND HIGH PRECISE INJECTION PRODUCTS}

The present invention relates to a micro-mold system, and more particularly, to a micro-mold system for manufacturing a micro-precision part having a multi-scale molding surface, a method of manufacturing the same, and a method of producing a micro-precision part using the same.

Plastic micro-precision parts are used in various fields such as optical products, electronic products, and bio-applied products such as microfluidic chips, and their utilization is increasing. The micro-mass molding technology is a technology for stably mass-producing such plastic micro-precision parts, and micro-injection molding and hot embossing are typical examples. In particular, since this technology enables continuous mass molding using a mold, it shows high productivity and excellent price competitiveness.

In the ultra-small mass molding technology, it is essential to precisely and stably manufacture a mold having a shape opposite to that of the micro-precision part to be formed. In order to manufacture such a mold, precision manufacturing techniques in the form of direct processing such as micro-precision machining, micro-electric discharge machining, and laser machining have been introduced. Using these technologies, it is possible to manufacture molds of various shapes, but since it takes a long manufacturing time, there is a limitation in that productivity is low and precision is not excellent.

Micro-precision parts with multi-scale molding surfaces are on a complex-shaped surface such as a surface composed of several stages with a predetermined height difference or a surface with slopes in various directions, unlike the general case in which microscopic irregularities are formed on a plane. It consists of a shape in which fine irregularities are provided. Such multi-scale micro-precision parts can realize improved degree of integration and various functions based on geometrical complexity, thus increasing the possibility of application.

In the case of manufacturing a multi-scale micro-precision part using micro-miniature mass molding technology, conventionally, due to the complex shape of the object, mold production using micro-miniature production technology of direct processing has been mainly made. However, these fabrication technologies have low fabrication efficiency, precision, and geometrical freedom.

The present invention is a micro-mold system capable of easily manufacturing a micro-precision part having a multi-scale molding surface of a complex shape, and improving production efficiency, precision, and geometrical freedom, and a method of manufacturing the same, and the production of micro-precision parts using the same I want to provide a way.

The micro-mold system according to an embodiment of the present invention is for manufacturing micro-precision parts by injection molding, and has at least two types of base molds having a molding surface with fine irregularities formed and having a different height from the bottom to the molding surface. It includes, and provides a multi-scale molding surface in which the first scale of the multistage structure and the second scale of the fine uneven structure are combined.

At least two types of base molds are arbitrarily combined so that the order can be changed, and may be in close contact with each other by an external force applied along a direction adjacent to each other. The molding surface can be positioned parallel to the floor. On the other hand, the molding surface may be formed as an inclined surface, and the molding surface of one base mold and the molding surface of the other base mold may have opposite inclined directions.

A molding surface of one of the at least two types of base molds and a molding surface of the other base mold may include convex portions positioned on the same line or may include convex portions that are offset from each other.

A method of manufacturing a micro-mold system according to an embodiment of the present invention includes the steps of attaching a mother substrate on a metal plate, forming an exposure mask on the mother substrate, and then patterning at least two different heights having fine irregularities on one side. Forming at least two types of intaglio patterns having the same shape as openings in the parent substrate by exposing and developing the parent substrate to one of X-rays and ultraviolet rays, and the metal plate exposed by the intaglio pattern The step of manufacturing at least two types of base molds having the same shape as an intaglio pattern by plating a metal material on the top, and combining at least two types of base molds so that the molding surface with fine irregularities is located on the same side, and then the base mold is combined It includes the step of applying an external force in close contact along the direction.

The parent substrate may be made of any one of an X-ray photosensitive material and an ultraviolet photosensitive material, and the exposure mask may be made of any one of an X-ray absorber and an ultraviolet absorber.

When forming the opening of the exposure mask, a side surface on which fine irregularities are formed may be formed to be parallel to the bottom of the opening.

On the other hand, when forming the opening of the exposure mask, one side on which the fine irregularities are formed may be formed to have an inclination angle with respect to the bottom of the opening. In this case, when the base mold is combined, the fine irregularities are formed in two adjacent base molds. It can be combined so that the inclined direction of the formed molding surface is opposite.

When plating a metallic material on a metal plate, nickel or a nickel alloy can be electroplated.

A method of manufacturing a micro-precise part according to an embodiment of the present invention includes the steps of producing at least two types of base molds having a molding surface with fine irregularities and having a different height from the bottom to the molding surface, and for injection molding Providing a multi-scale molding surface in which a first scale of a multi-stage structure and a second scale of a fine uneven structure are combined by arranging at least two types of base molds in the interior of the mold core so that the molding surface is exposed, and the molding surface And manufacturing a multi-scale micro-precision part having a molding surface having a shape opposite to that of the molding surface by injection molding plastic through the injection molding process.

According to embodiments of the present invention, since the molding surface of the micro-mold system may be complicated by combining at least two types of base molds alone or in plurality, it is possible to easily manufacture micro-precision parts having various various shapes. As a result, it is possible to design and develop functional precision parts that can perform various additional functions that were difficult to implement with existing technologies, and in particular, sheets with fine light patterns and microfluidic chips that perform complex microfluidic functions with high precision. It can be easily manufactured.

1 and 2 are an exploded perspective view and a combined perspective view of the micro mold system according to the first embodiment of the present invention, respectively.
3 is a perspective view of a micro mold system according to a second embodiment of the present invention.
4 is a perspective view of a micro mold system according to a third embodiment of the present invention.
5 is a flowchart illustrating a method of manufacturing a micro mold system according to an embodiment of the present invention.
6 is a schematic perspective view showing a parent substrate of the first step and the second step shown in FIG. 5.
7 is a schematic perspective view showing the parent substrate of the third step shown in FIG. 5.
FIG. 8 is a schematic perspective view showing a parent substrate and a base mold in a fourth step shown in FIG. 5.
9 is a process flow chart showing a method of manufacturing a micro-precision component according to an embodiment of the present invention.
10 is an enlarged photograph of an exposure mask showing portion A of FIG. 6.
11 is a photograph showing a parent substrate and a titanium plate on which an intaglio pattern is formed.
12 is a photograph showing a mold core for injection molding in which a plurality of base molds are mounted.
13 is a photograph showing a molding surface of a micro-precision part manufactured according to the processing example of the present invention.
14 and 15 are enlarged photographs of FIG. 13.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. The present invention may be implemented in various different forms, and is not limited to the embodiments described herein.

1 and 2 are an exploded perspective view and a combined perspective view of the micro mold system according to the first embodiment of the present invention, respectively.

1 and 2, the micro-mold system 100 of the first embodiment is for injection-molding a plastic micro-precision part, and is formed from the bottom while having the molding surfaces 11, 12, and 13 formed with fine irregularities. It includes at least two types of base molds 21, 22, 23 having different heights up to the faces 11, 12, 13.

The micro mold system 100 includes a first base mold 21 having a first molding surface 11 and having a first height h1 from the bottom to the first molding surface 11, and a second molding surface ( 12) and having a second base mold 22 having a second height h2 from the bottom to the second molding surface 12, and a third molding surface 13, and having a third molding surface 13 from the bottom. A third base mold 23 having a third height h3 up to) may be included. At this time, the first height h1, the second height h2, and the third height h3 have different values.

In FIGS. 1 and 2, a case in which the first height h1 is the largest and the third height h3 is the smallest is illustrated as an example. The difference between the first height h1 and the second height h2 and the difference between the second height h2 and the third height h3 may be the same or different. In FIGS. 1 and 2, a case in which the difference between the first height h1 and the second height h2 and the difference between the second height h2 and the third height h3 is the same is illustrated as an example.

The first to third molding surfaces 11, 12, 13 include convex and concave parts, and can be formed in various shapes according to the shape of the molding surface of the micro-precision part to be made such as a triangle, a sawtooth shape, and a sine wave. have. The height of the base mold (21, 22, 23), defined as the vertical distance from the bottom to the shaping surface (11, 12, 13), is relative to the top of the convex, the bottom of the convex, or the middle between the top and the bottom of the convex. You can do it on a point basis.

The height difference between the base molds 21, 22, and 23 may be greater than the height of the convex portion (or the depth of the concave portion) constituting the fine irregularities and the maximum width of the convex portion or the concave portion. However, it is not necessarily limited to the above-described case and can be variously changed according to the specifications of the micro-precision parts to be manufactured.

The base molds 21, 22, and 23 may be made of a metal having excellent mechanical properties, such as nickel or a nickel alloy. The first to third base molds 21, 22, 23 are arranged so that the molding surfaces 11, 12, 13 are located on the same side, and the thickness direction of the base molds 21, 22, 23 (x-axis in the drawing) Direction), the three molding surfaces 11, 12, 13 are in close contact with each other so that they are connected.

The first to third base molds 21, 22, and 23 are combined so as not to be permanently bonded with an adhesive or the like, but to maintain only a state in close contact with each other by an external force. And each base mold (21, 22, 23) is a

Its position can be changed to suit the shape. That is, each of the base molds 21, 22, and 23 is appropriately combined and disposed inside the mold core for injection molding to be described below, and is used for injection molding plastic micro-precision parts.

The first to third molding surfaces 11, 12, 13 are parallel to the floor, and the convex portions are formed to be located in a straight line along the thickness direction (x-axis direction of the drawing) of the base molds 21, 22, 23. I can. On the other hand, at least two of the first to third molding surfaces 11, 12, 13 have a convex position along the longitudinal direction (y-axis direction of the drawing) of the molding surfaces 11, 12, 13 It may be formed to deviate from each other. In FIG. 2, the first case is illustrated as an example, and micro-precision parts having various shapes can be manufactured than in the second case.

When the positions of the convex portions are shifted from each other, at least two of the first to third forming surfaces 11, 12, and 13 may be formed in a shape in which the positions of the convex portions are shifted. In this case, the first to third base molds 21, 22, and 23 are arranged side by side. On the other hand, the first to third molding surfaces 11, 12, 13 may be formed in the same shape in which the convex portions are located, in this case, at least two of the first to third base molds 21, 22, 23 The base mold of is disposed so that its sides are offset from each other.

As described above, the micro-mold system 100 has a configuration in which two or more types of base molds 21, 22, and 23 having different heights are combined to form a multi-scale molding surface 30. Here, the multi-scale refers to a shape in which a first scale having a multistage structure having a height difference between each other and a second scale having a concave-convex structure in which concave portions and convex portions are repeatedly arranged at the same basic height are combined. Mainly, the size of the first scale (the height difference) may be larger than the size of the second scale (the height of the convex portion and the maximum width of the convex portion).

Accordingly, by injection molding plastic with the above-described multi-scale molding surface 30, a multi-scale plastic micro-precision component having a molding surface having a shape opposite to that of the molding surface 30 can be manufactured.

Meanwhile, in FIGS. 1 and 2, a micro mold system 100 including three types of base molds 21, 22, and 23 having different heights is shown, but the micro mold system 100 has two types of different heights. It may include a base mold of.

3 is a perspective view of a micro mold system according to a second embodiment of the present invention.

3, the micro-mold system 110 of the second embodiment has the same configuration as the micro-mold system of the first embodiment, except that a plurality of first to third base molds 21, 22, and 23 are combined. Consists of The same quotation marks are used for the same members as in the first embodiment.

The first to third base molds 21, 22, and 23 may be arranged in a certain rule. In FIG. 3, the first base mold 21, the second base mold 22, and the third base mold 23 are repeatedly arranged in order. However, the order of the base mold is not limited to the illustrated example, and the first base mold 21, the second base mold 22, the third base mold 23, the second base mold 22, and the first base mold Various combinations are possible, such as (21) being repeatedly arranged.

The micro-mold system 110 of the second embodiment is more advantageous for mass-molding micro-precision parts because it forms a molding surface 31 having a larger area than that of the first embodiment.

4 is a perspective view of a micro mold system according to a third embodiment of the present invention.

Referring to FIG. 4, the micro-mold system 120 according to the third embodiment includes at least two types of base molds 24 and 25 whose inclined directions are opposite while forming surfaces 14 and 15 on which fine irregularities are formed are formed as inclined surfaces. Include.

That is, in the micro-mold system 120, the fourth molding surface 14 on which the fine irregularities are formed is along the length direction of the fourth molding surface 14 (the y-axis direction of the drawing) from one side to the opposite side (left side based on the drawing). A fourth base mold 24 that rises toward the right) and a fifth base that lowers from one side to the other side along the length direction of the fifth molding surface 15 and the fifth molding surface 15 with fine irregularities formed thereon. Includes a mold 25.

The micro-mold system 120 includes one fourth base mold 24 and one fifth base mold 25, or alternately repeats the fourth base mold 24 and the fifth base mold 25 one by one. It can be made in a combination arranged. In FIG. 4, the second case is illustrated as an example. Accordingly, the molding surface 32 of the micro-mold system 120 has a predetermined height difference (step difference) between the adjacent base molds 24 and 25 in the rest area except for the central part, and this height difference is the molding surface 32 It gets bigger toward both edges of

Also in the micro-mold system 120 of the third embodiment, the fourth and fifth molding surfaces 14 and 15 are in the thickness direction of the fourth and fifth base molds 24 and 25 (the x-axis direction in the drawing). It can be positioned so that the convex portions are the same or deviated from each other. Using the micro-mold system 120 of the third exemplary embodiment described above, a multi-scale micro-precision part having an inclined surface and fine irregularities formed on the inclined surface may be manufactured by injection molding.

Next, a method of manufacturing the micro-mold system will be described.

5 is a flowchart illustrating a method of manufacturing a micro mold system according to an embodiment of the present invention.

Referring to FIG. 5, the method of manufacturing a micro-mold system includes a first step (S10) of attaching a mother substrate on a metal plate, and a first step of forming at least two types of openings by patterning an exposure mask on the mother substrate. Step 2 (S20) and a third step (S30) of forming at least two types of intaglio patterns on the parent substrate by developing after exposure to the mother substrate, and plating at least two types of metal materials on the metal plate exposed by the intaglio patterns. And a fourth step (S40) of manufacturing a base mold of and a fifth step (S50) of applying an external force after combining at least two types of base molds.

6 is a schematic perspective view showing the parent substrate of the first step and the second step shown in FIG. 5, and FIG. 7 is a schematic perspective view showing the parent substrate of the third step shown in FIG. 5.

Referring to FIG. 6, a metal plate 50 is attached under the parent substrate 40, and an exposure mask 60 is formed on the parent substrate 40.

The parent substrate 40 is formed of an X-ray photosensitive material in case of X-ray exposure, and is formed of an ultraviolet ray photosensitive material in case of UV exposure.

The parent substrate 40 may be made of a polymer resin, for example, polymethyl methacrylate (PMMA), and the metal plate 50 may be a titanium plate. The exposure mask 60 is formed of an X-ray absorber in case of X-ray exposure, and is formed of an ultraviolet absorber in case of UV exposure. Gold may be used as an X-ray absorber.

The exposure mask 60 is patterned to form openings 61, 62, and 63 having the same shape as the base mold to be made. That is, the openings 61, 62, 63 include at least two types of openings 61, 62, 63 having fine irregularities formed on one side and having different heights from the bottom to the fine irregularities. One side of the openings 61, 62, and 63 in which the fine irregularities are formed may have a predetermined inclination angle. 6, a first opening 61 having a first height h1, a second opening 62 having a second height h2, and a third opening 63 having a third height h3 ) Is shown as an example.

Only portions of the parent substrate 40 corresponding to the openings 61, 62, and 63 of the exposure mask 60 are exposed to the outside. In this state, X-rays are irradiated to the parent substrate 40 using a radiation accelerator, or ultraviolet rays are irradiated to the parent substrate 40 using an ultraviolet lamp, followed by a development process. In the exposure process, the lower portion of the exposure mask 60 of the parent substrate 40 is blocked by X-rays or ultraviolet rays, while the portions exposed by the openings 61, 62, 63 are X-rays or ultraviolet rays. As it is exposed to, solubility increases. The portion of increased solubility is removed in the developing process.

Therefore, as shown in FIG. 7, at least two types of intaglio patterns 41, 42, 43 having the same shape as the openings 61, 62, 63 are formed in the parent substrate 40, and after the development process, the exposure mask ( 60) is removed.

FIG. 8 is a schematic perspective view showing a parent substrate and a base mold in a fourth step shown in FIG. 5.

Referring to FIG. 8, a metal material having excellent mechanical properties such as nickel or a nickel alloy is plated on a metal plate 50 corresponding to the intaglio patterns 41, 42, and 43 to form the same shape as the intaglio patterns 41, 42, 43. At least two types of base molds 21, 22, and 23 are manufactured. Thereafter, the base molds 21, 22, and 23 are separated from the parent substrate 40 and the metal plate 50, and the manufactured base molds 21, 22, and 23 are combined to complete a micro mold system.

The micro-mold system combines at least two types of base molds with different heights from the bottom to the molding surface or opposite inclined directions to form multi-scale molding surfaces. Therefore, it is possible to easily manufacture micro-precision parts having multi-scale molding surfaces, and it is advantageous to mass-produce micro-precision parts when the area of the molding surfaces is increased by increasing the number of base molds to be combined.

9 is a process flow chart showing a method of manufacturing a micro-precision component according to an embodiment of the present invention.

Referring to FIG. 9, the method of manufacturing a micro-precision part includes a first step (S100) of manufacturing at least two types of base molds having different heights from the bottom to the molding surface, and molding inside the mold core for injection molding. A second step (S200) of combining at least two types of base molds so that the surfaces are exposed, and plastic injection molding with a micro-mold system to manufacture a micro-precision part having a molding surface opposite to that of the base mold. It includes a third step (S300).

In the first step (S100), at least two types of base molds are formed such that the molding surface on which the fine irregularities are formed is parallel to the floor or has a predetermined inclination angle. In the second step (S200), the mold core for injection molding forms an inner space for mounting the base mold, and at least two types of base molds are closely disposed in the inner space. In the third step (S300), plastic is injection-molded using the molding surface of the micro mold system, thereby manufacturing a micro-precision part having a molding surface having a shape opposite to that of the micro mold system.

In this way, by combining at least two types of base molds singly or in plurality, the molding surface of the micro-mold system can be complicated, and as a result, it is possible to easily manufacture micro-precision parts having a complex shape. Therefore, it is possible to design and develop functional precision parts that can perform various additional functions that were difficult to implement with existing technologies.

In particular, it is possible to manufacture a sheet having a microscopic light pattern and a microfluidic chip that performs a complex microfluidic function.

Example

A 1 mm thick parent substrate formed of polymethyl methacrylate (PMMA) was attached on the titanium plate. An exposure mask was formed by applying an X-ray material on the parent substrate, and then the exposure mask was patterned to form three types of openings having a height difference of 100 μm.

Fig. 10 is an enlarged photograph of the exposure mask and shows portion A in Fig. 6. In FIG. 10, the black portion is the exposure mask 50, and the bright portion is the surface of the parent substrate 40 exposed by the opening of the exposure mask 50. The fine irregularities formed on the exposure mask have a shape in which triangular convex portions having a base length of 150 µm and a height of 50 µm are arranged in succession based on the opening.

Thereafter, X-rays were irradiated onto the parent substrate using a radiation accelerator, and then developed to form an intaglio pattern having the same shape as an opening in the parent substrate. In FIG. 11, photographs of the parent substrate 40 on which the intaglio patterns 41, 42, and 43 are formed and the titanium plate 50 positioned on the rear surface of the parent substrate 40 are shown.

Subsequently, a nickel electroplating process was performed on the titanium plate exposed by the intaglio pattern to produce a base mold having the same shape as the intaglio pattern. And after separating the base mold from the parent substrate and the titanium plate, the base mold was mounted inside the mold core for injection molding.

12 is a photograph showing a mold core for injection molding in which a plurality of base molds are mounted. In Fig. 12, reference numeral 70 denotes a mold core for injection molding, and reference numeral 33 denotes a molding surface of the base mold. In FIG. 12, the molding surfaces 33 of some of the base molds are parallel to the bottom, and the molding surfaces 33 of the other base molds have a predetermined inclination angle. The combination of the base mold shown in FIG. 12 is an example and can be modified in various combinations.

A micro-precision part was manufactured by injection-molding plastic using the mold core for injection molding shown in FIG. 12. 13 is a photograph showing the molding surface 34 of the manufactured micro-precision part, and FIGS. 14 and 15 are enlarged photographs of FIG. 13. 13 to 15, the molding surface 34 of the micro-precision part has a shape opposite to that of the molding surface 33 of the base mold, and the first scale of the multistage structure and the second scale of the uneven structure are combined. You can see that the scale is being implemented.

In the above, preferred embodiments of the present invention have been described, but the present invention is not limited thereto, and it is possible to implement various modifications within the scope of the claims, the detailed description of the invention, and the accompanying drawings. It is natural to fall within the scope of

100, 110, 120: micro mold system
11, 12, 13, 14, 15: first to fifth molding surfaces
21, 22, 23, 24, 25: first to fifth base molds
30, 31, 32, 33, 34: forming surface
40: parent substrate
50: metal plate
61, 62, 63: opening

Claims (14)

A micro-mold system for manufacturing micro-precision parts by injection molding, comprising at least two types of base molds having a molding surface with fine irregularities and having a different height from the bottom to the molding surface, and having a multistage structure. A micro-mold system in which a first scale and a second scale having a fine uneven structure are combined to provide a multi-scale molding surface, and the at least two types of base molds are arbitrarily combined so that an order can be changed. The method of claim 1,
The at least two types of base molds are in close contact with each other by an external force applied along a direction adjacent to each other. The method of claim 2,
The molding surface is a micro-mold system located parallel to the floor. The method of claim 2,
The molding surface is a micro mold system formed as an inclined surface. The method of claim 4,
A micro-mold system in which a molding surface of one of the at least two types of base molds and a molding surface of the other base mold have opposite inclination directions. The method according to any one of claims 3 to 5,
A micro-mold system including a convex portion disposed on the same line between a molding surface of one of the at least two types of base molds and a molding surface of the other base mold. The method according to any one of claims 3 to 5,
A micro-mold system comprising a convex portion in which a molding surface of one of the at least two types of base molds and a molding surface of the other base mold are positioned to be offset from each other. Attaching a parent substrate on the metal plate; Forming at least two types of openings having fine irregularities on one side and having different heights by patterning after forming an exposure mask on the parent substrate; Forming at least two types of intaglio patterns having the same shape as the opening in the parent substrate by exposing the parent substrate to X-ray and ultraviolet rays and developing; Plating a metal material on the metal plate exposed by the intaglio pattern to manufacture at least two types of base molds having the same shape as the intaglio pattern; And combining the at least two types of base molds such that the molding surfaces on which the fine irregularities are formed are located on the same side, and then applying an external force along the combined direction of the base molds to make them in close contact with each other. The method of claim 8,
The parent substrate is made of any one of an X-ray photosensitive material and an ultraviolet photosensitive material, and the exposure mask is made of any one of an X-ray absorber and an ultraviolet absorber. The method of claim 8,
When forming the opening of the exposure mask, a method of manufacturing a micro-mold system, wherein a side surface on which the fine irregularities are formed is parallel to a bottom of the opening. The method of claim 8,
When forming the opening of the exposure mask, a method of manufacturing a micro-mold system, wherein a side surface on which the fine irregularities are formed has an inclination angle with respect to the bottom of the opening. The method of claim 11,
When combining the base molds, a method of manufacturing a micro-mold system in which two adjacent base molds are combined so that the inclined directions of the molding surfaces on which the fine irregularities are formed are opposite. The method of claim 8,
A method of manufacturing a micro-mold system for electroplating nickel or a nickel alloy when plating a metal material on the metal plate. Manufacturing at least two types of base molds having a molding surface having fine irregularities formed thereon and having different heights from the bottom to the molding surface; Providing a multi-scale molding surface in which the first scale of the multi-stage structure and the second scale of the fine concave-convex structure are combined by arranging the at least two types of base molds in combination to expose the molding surface inside the mold core for injection molding step; And manufacturing a multi-scale micro-precision part having a molding surface having a shape opposite to the molding surface by injection molding plastic through the molding surface.

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