HK1069152A

HK1069152A - Apparatus for embossing a flexible substrate with a pattern carried by an optically transparent compliant media

Info

Publication number: HK1069152A
Application number: HK05102501.3A
Authority: HK
Inventors: Hua Jeans Albert
Original assignee: 惠普开发有限公司
Priority date: 2003-04-29
Filing date: 2005-03-22
Publication date: 2005-05-13

Description

Apparatus for embossing a flexible substrate with a pattern carried by an optically transparent compliant media

Technical Field

The present invention relates generally to an apparatus for embossing a flexible substrate. More particularly, the present invention relates to an apparatus for embossing a photopolymer coated flexible substrate having an imprint pattern transferred from an imprint stamp carried by an optically transparent compliant media. The imprint stamp is irradiated with ultraviolet light through the compliant media and simultaneously embossed such that the transferred imprint pattern solidifies, hardens, and retains its shape.

Background

Current roll-to-roll flexographic processes for embossing photopolymer coated webs include the method and apparatus employed by Epigem limited wherein a web transparent to ultraviolet light is coated with a blanket of photopolymer and the coated side of the web is contacted with an embossing shim that carries the embossing pattern. When the web is separated from the embossing shim, the embossed pattern is embossed (i.e., replicated) in the photopolymer cover layer. An ultraviolet light source irradiates the photopolymer cover layer through the web and cures the embossed pattern so that the pattern hardens and retains its embossed shape. Because the web is transparent to ultraviolet light, the orientation of the ultraviolet light source is not a problem, the embossing shim can be opaque to ultraviolet light, and the irradiation can be from the web side.

One drawback of the above-described apparatus is that if the web and embossing shim are not transparent to ultraviolet light, the irradiation does not effectively proceed from either the web side or the embossing shim side. Thus, if the web is opaque to UV light as required by the web-fed process, the embossing shim must be optically transparent to UV light so that the radiation of the embossed pattern in the photopolymer coating can proceed from the side of the embossing shim.

In contrast, researchers at universities (e.g., University of Texas at Austin, Step and flash Impprint Lithology) have employed quartz shims (templates) that are optically transparent to ultraviolet light. However, this process is a batch oriented wafer-based process that is not suitable for a rotary flexo process.

Accordingly, there remains a need for an apparatus for performing a rotary flexographic printing process in which an optically transparent compliant media carrying an imprint stamp is used to emboss a pattern in a photopolymer coated on an opaque flexible substrate. There is also a need for an apparatus that allows a pattern embossed in a flexible substrate to be cured by ultraviolet light that irradiates the pattern through the compliant media and the imprint stamp.

Disclosure of Invention

In general, the invention is embodied in an apparatus for embossing a flexible substrate having a pattern carried by an optically transparent compliant media. The compliant media includes an optically transparent imprint stamp including an imprint pattern. The compliant media can be coupled to an optically transparent belt liner or an optically transparent cylinder.

The flexible substrate includes a coated side coated with a photopolymer material, the coated side being urged into contact with the compliant media such that an imprint pattern carried by the imprint stamp is embossed in the photopolymer material. An ultraviolet light source irradiates the photopolymer material with ultraviolet light that passes through the compliant media and the imprint stamp and impinges on the pattern embossed in the photopolymer material to cure the pattern. The curing of the pattern in the photopolymer material is performed simultaneously with the embossing so that the pattern hardens and retains its shape.

One advantage of the apparatus of the present invention is that radiation is transmitted through the compliant media such that the flexible substrate is opaque to ultraviolet light.

Another advantage of the present invention is that the ultraviolet light source can be located inside or outside of the belt liner to which the compliant media is attached. If a cylinder is used, the ultraviolet light source can be located inside or outside of the cylinder to which the compliant media is connected.

Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

Drawings

FIGS. 1 through 5 depict the patterning and etching of a master substrate of the present invention to define an imprint pattern;

FIG. 6 depicts a release layer of the present invention conformally deposited over the imprint pattern;

FIG. 7 depicts a silicone-based elastomer layer deposited onto a release layer in accordance with the present invention;

FIGS. 8 through 10 depict the separation of the silicone-based elastomer layer and the release layer of the present invention to form an imprint stamp;

FIG. 11 depicts the application of a thin plastic film to a silicone rubber backing of the present invention;

FIG. 12 depicts the coating of a thin plastic film with a photopolymer solution according to the present invention;

FIGS. 13 and 14 depict dispensing a photopolymer solution to form a photopolymer layer on a thin plastic film in accordance with the present invention;

FIG. 15 depicts the invention placing the patterned side of the imprint stamp on the photopolymer layer;

FIG. 16 depicts the curing of a photopolymer layer of the present invention;

FIG. 17 depicts the present invention removing the imprint stamp from the photopolymer layer;

FIG. 18 depicts a photopolymer shim formed in a photopolymer layer of the present invention;

FIG. 19 depicts a fluorocarbon coating deposited on a photopolymer shim according to the present invention;

FIG. 20 depicts a photopolymer shim attached to a support substrate of the present invention;

FIG. 21 depicts the preheating of the shim stock and support substrate attached to the support substrate of the present invention;

FIGS. 22 and 23 depict the application and dispersion of a silicone-based elastomer material to a photopolymer shim and a shim stock in accordance with the present invention;

FIG. 24 depicts heating of a support substrate of the present invention;

FIGS. 25 through 27 depict the application of a transfer adhesive to a compliant media according to the present invention;

FIG. 28 depicts the separation of the compliant media from the support substrate of the present invention;

FIG. 29 is a top plan view and a cross-sectional view of an imprint pattern carried by a photopolymer shim of the present invention;

FIG. 30 depicts a compliant assembly of the present invention;

FIGS. 31 a-34 b depict the present invention connecting a compliant assembly to a cylinder;

FIGS. 35 through 37b depict the attachment of a compliant assembly to a belt liner in accordance with the present invention;

FIGS. 38 and 39 are schematic diagrams depicting an apparatus for embossing a flexible substrate with an optically transparent compliant media coupled with an optically transparent tape liner in accordance with the present invention;

FIGS. 40 and 41 are schematic diagrams depicting an apparatus for embossing a flexible substrate with an optically transparent compliant media coupled to an optically transparent cylinder in accordance with the present invention;

FIG. 42 is a schematic view of a coating unit of the present invention;

fig. 43 is a schematic view of a coating unit including a gravure type coater of the present invention;

FIG. 44 is a schematic view of a coating unit including a slot die coater of the present invention;

FIG. 45 is a cross-sectional view depicting irradiation of a photopolymer material through an optically transparent belt liner, a compliant media, and an imprint stamp in accordance with the present invention;

FIG. 46 is a cross-sectional view depicting irradiation of a photopolymer material through an optically transparent cylinder, a compliant media and an imprint stamp in accordance with the present invention;

FIG. 47 is a top plan view and a cross-sectional view of a replicate pattern embossed in a photopolymer material according to the present invention.

Detailed Description

In the following detailed description and in the several figures of the drawings, like elements are referred to by like reference numerals.

In fig. 38 to 47, an embossing apparatus including an optically transparent embossing belt or an optically transparent embossing drum is shown.

In FIGS. 1 through 37b, a method of manufacturing an optically transparent compliant media that can be coupled to an optically transparent belt liner or optically transparent cylinder is illustrated.

As shown in the drawings for illustrative purposes, the present invention is embodied in a die set apparatus. In one embodiment of the present invention, an embossing apparatus includes a flexible substrate having a coated side and a bottom side, a coating unit for depositing a photopolymer material having a first thickness on the coated side of the flexible substrate, and an embossing belt including an optically transparent belt liner and an optically transparent compliant media coupled to the belt liner. The compliant media includes an optically transparent imprint stamp having an imprint pattern embossed in a photopolymer material on a coated side to form a replicate pattern in the photopolymer material. A plurality of transport rollers are coupled to the belt liner and support the embossing belt during operation.

A drive unit imparts a driving motion to the embossing belt and the flexible substrate such that the coated side contacts the imprint stamp and the imprint pattern is replicated in the photopolymer material. The support roller is wrapped by a portion of the bottom surface of the flexible substrate and a portion of the compliant media such that a tension is imparted to the embossing belt and the tension creates a pressure between the flexible substrate and the embossing belt.

The drive motion is operative to transport the backside of the flexible substrate to the backing roll and to urge the imprint stamp and the coated side into contact with each other such that the imprint pattern is embossed in the photopolymer material to form a replicate pattern in the photopolymer material. The ultraviolet light source irradiates the replicate pattern with ultraviolet light that passes through the belt liner, the compliant media, and the imprint stamp. The irradiation of the replicate pattern is performed simultaneously with the embossing of the replicate pattern so that the replicate pattern cures, hardens, and retains its shape.

In an alternative embodiment of the present invention, a stamping apparatus includes a flexible substrate having a coated side and a bottom side, a coating unit that deposits a photopolymer material having a first thickness onto the coated side of the flexible substrate, and a stamping cylinder including an optically transparent cylinder and an optically transparent compliant media coupled to the cylinder. The compliant media includes an optically transparent imprint stamp having an imprint pattern that will be embossed in the photopolymer material on the coated side to form a replicated pattern in the photopolymer material.

A drive unit imparts a driving motion to the embossing drum and the flexible substrate such that the coated side is in contact with the imprint stamp and the imprint pattern is replicated in the photopolymer material. A plurality of transfer rolls are coupled to the base surface and are operable to conformally wrap the coated surface around a portion of the embossing drum such that the embossing drum imparts a tension to the flexible substrate and the tension creates a pressure between the flexible substrate and the embossing drum.

The drive motion is operative to transport the coated side to the embossing drum and to urge the imprint stamp and the coated side into contact with each other such that the imprint pattern is embossed in the photopolymer material to form a replicate pattern in the photopolymer material. The ultraviolet light source irradiates the replicate pattern with ultraviolet light that passes through the platen, the compliant media, and the imprint stamp. The irradiation of the replicate pattern is performed simultaneously with the embossing of the replicate pattern so that the replicate pattern cures, hardens, and retains its shape.

In fig. 38, the embossing apparatus 200 includes a flexible substrate 101 including a coated side 101c and a bottom side 101 b. The coating unit 300 is operative to deposit a photopolymer material 301 (see FIGS. 42, 43 and 44) onto the coated side 101 c. The photopolymer material 301 has a first thickness t_c. The embossing belt 100 includes an optically transparent belt liner 81 and an optically transparent compliant media 70, with the optically transparent compliant media 70 being connected to the belt liner 81 (see FIG. 45). The compliant media 70 also includes an optically transparent imprint stamp 20t that includes an imprint pattern 20q (see FIG. 29). Because the imprint pattern 20q is formed from the same material as the imprint stamp 20t, the imprint pattern 20q is also optically transparent. Fig. 45 and 37a, 37b provide a more detailed view of the embossing belt 100 than that depicted in fig. 38 and 39.

A plurality of transport rollers 103 are connected to the belt liner 81 and support the embossing belt 100 in operation. The drive unit 110 will drive the movement W_DAn embossing belt 100 and a flexible substrate 101 are imparted. As described below, the drive unit 110 may be coupled to the molding apparatus 200 in a variety of ways to accomplish the drive motion W_D。

The backing roll 105 is wrapped by a portion of the bottom surface 101b of the flexible substrate 101 and a portion of the compliant media 70, which imparts a tension to the embossing belt 100 and the flexible substrate 101. The tension creates a pressure between the flexible substrate 101 and the embossing belt 100. This pressure is operative to effect embossing of the imprint stamp 20t in the photopolymer material 301. Drive motion D_RIn operation, the bottom surface 101b is transported to the backing cylinder 105 and the imprint stamp 20t and the coated surface 101c are urged into contact with each other, thus embossing the imprint pattern 20q in the photopolymer material 301 and forming a replicate pattern 20u in the photopolymer material 301 (see FIG. 47).

The ultraviolet light source 99 irradiates the replicate pattern 20u with ultraviolet light L that passes through the belt material 81 and the imprint stamp 20 t. The irradiation of the replicate pattern 20u is performed simultaneously with the embossing of the replicate pattern 20u so that the replicate pattern 20u cures, hardens, and retains its shape. The replicate pattern 20u includes a plurality of patterns 20v therein that complement the patterns 20p on the master substrate 11 (see fig. 5 and 6).

The ultraviolet light source 99 can include a reflector 99r that focuses the ultraviolet light L to a position that pushes the imprint stamp 20t into contact with the coated side 101c so that the photopolymer material 301 is not cured by the ultraviolet light L prior to embossing the imprint pattern 20q therein. In FIG. 45, reflector 99r (not shown) forms a curing window C_wWhich focuses the ultraviolet light L on the areas where the replicate pattern 20u will be embossed and cured at approximately the same time. The reflector 99r also operates to prevent the dispersion of the ultraviolet light L that could potentially impinge on the photopolymer material 301 and cause it to cure prior to embossing by the imprint stamp 20 t.

One advantage of the present invention is that the embossing apparatus 200 is effective to emboss and cure the photopolymer material 301 when the flexible substrate 101 is opaque to the ultraviolet light L because the radiation of the replicate pattern 20u is directed through the embossing belt 100 as opposed to through the flexible substrate 101. Accordingly, the embossing apparatus 200 of the present invention can be used to emboss and cure the photopolymer material 301 on the opaque flexible substrate 101 or the optically transparent flexible substrate 101. Because some applications require that the material used for the flexible substrate 101 be an opaque material, the embossing apparatus 200 of the present invention is flexible in selecting the material of the flexible substrate 101.

The ultraviolet light source 99 may be a UVA ultraviolet light source, and is preferably an industrial grade UVA light source, as it desirably cures the replicate pattern 20u in a short time of about 0.1 seconds to about 6.0 seconds. Preferably, the ultraviolet light L has a wavelength of about 300.0nm to about 400.0 nm. The intensity of the ultraviolet light source 99 is also application dependent; however, as an example, a range of about 200.0mW/cm may be employed²To about 1000.0mW/cm²The strength of (2). As another example, Norland^TMThe optical adhesive requires curing of about 0.2Joules/cm²Total energy of (c).

Because the irradiation of the photopolymer material 301 is performed through the embossing belt 100, the ultraviolet light source 99 can have a position relative to the embossing belt 100 that includes a position inside the embossing belt 100 as shown in FIGS. 39 and 45 and a position outside the embossing belt 100 as shown in FIGS. 38 and 45. When the ultraviolet light source 99 is located outside the embossing belt 100 as shown in fig. 38, it is necessary to take into account a slight attenuation in the intensity of the ultraviolet light L caused by the ultraviolet light L passing through two layers of the embossing belt 100 as opposed to one layer when the ultraviolet light source 99 is located inside the embossing belt 100. Therefore, a higher intensity ultraviolet light source 99 may be required when the ultraviolet light source 99 is located outside the embossing belt 100.

In fig. 39, three transfer rollers 103 are used to form a space to accommodate the ultraviolet light source 99 on the inside of the embossing belt 100. However, because the compliant media 70 can be made to any size, there are a number of ways to accommodate the ultraviolet light source 99 on the inside of the embossing belt 100, including making the embossing belt 100 longer and making the diameter of the transfer rollers 103 larger to create a space large enough to accommodate the ultraviolet light source 99. Thus, the embodiment of FIG. 39 is merely one example of how the ultraviolet light source 99 on the interior of the embossing belt can be accommodated, and other configurations can be used, and the invention is not limited to the configuration shown in FIG. 39.

In fig. 42, the coating unit 300 will have a first thickness t in operation_cIs deposited on the coated side 101 c. Generally, the photopolymer material 301 is supplied as a liquid 301L prior to deposition onto the coated side 101 c. In a driving movement W_DIs important, the coating distance D between the coated side 101c and the coating unit 300_cShould be maintained accurately so that the first thickness t_cIt does not change and the photopolymer material 301 is deposited as a smooth and uniform layer on the coated side 101 c. The photopolymer material 301 can include, but is not limited to, Norland that cures when exposed to ultraviolet light^TMAn optical adhesive. Preferably, the photopolymer material cures in a time of about 0.1 seconds to about 6.0 seconds. For example, Norland  NOA 83H photopolymer can be used for the photopolymer material 301. The photopolymer material 301 can also be a photoresist material.

Optionally, the embossing device 200 may comprise a guide roll 109 which, in operation, maintains a constant distance D between the coated side 101c and the coating unit 300_cSuch that the first thickness t of the photopolymer material 301_cIs accurately maintained. The guide roller 109 is particularly useful when the supply reel 107s is used to carry and dispense the flexible substrate 101. As the flexible substrate 101 is unwound from the supply reel 107s, its distance from the coating unit 300 changes, and increases as the winding diameter of the flexible substrate 101 decreases as the flexible substrate 101 is unwound from the supply reel 107 s. Thus, the guide roll 109 controls the distance between the coated side 101c and the coating unit 300.

First thickness t of photopolymer material 301_cDepending on the application, and the type of coating unit 300 may also depend onDepending on the application. A first thickness t_cGeneral and typical feature height (see h in FIG. 4)₀) Rather, in order to minimize the mold residue of a subsequent etch of the mold layer. For example, if the imprint stamp 20t includes imprint patterns 20q on a nanometer scale (e.g., less than 1.0 μm, preferably less than 100.0nm), then it may be desirable to deposit a thin layer of photopolymer material 301. Preferably, the first thickness t_cIn the range of about 0.05 μm to about 2.0 μm.

Coating techniques that can deposit a uniform and thin layer of photopolymer material 301 and can be used in the coating unit 300 include, but are not limited to, gravure coater, micro gravure^TMCoaters and slot die coaters. For example, the first thickness t_cThe above thickness range of (A) can be obtained using Yasui Selkl^TMMicro gravure printing^TMCoating machine to obtain. The photopolymer material 301 can be thinned using a solvent, such as acetone, to achieve a thinner first thickness t_cCoating of (2).

In fig. 43, the coating unit 300 may be a gravure coater or a micro gravure^TMA coating machine. A pair of rollers 303r conformally wrap a portion of the coated side 101c of the flexible substrate 101 over an engraved cylinder 303g, which engraved cylinder 303g rotates within a trough 303s containing a liquid photopolymer material 303L. The photopolymer material 301L is concentrated on the pattern on the surface of the drum 303 g. The doctor blade 303d scrapes off the excess photopolymer material 301L, thus depositing a thin and uniform layer on the coated side 101 c. Preferably, micro gravure is used^TMThe coater, because it has a roller 303g with a smaller diameter than the gravure coater, is more suitable for depositing ultra-thin layers of photopolymer material 301.

Alternatively, a slot die coater may be used to deposit the photopolymer material 301 in FIG. 44. The liquid photopolymer material 301L is supplied under pressure (S)_f) To a die slot 301S formed by a pair of die lips 301D. The die lip 301D is spaced from the flexible substrate 101 by a coating gap t_cIncluding the thickness t of the flexible substrate 101_s. When the coated side 101c of the flexible substrate 101 passes under the die slit 301S, the liquid photopolymerThe material 301L coats the coated side 101c to a first thickness t_cThe above.

Drive movement t_cThis can be achieved by using a variety of techniques well known in the coating and mechanical arts. As an example, in fig. 38, a drive unit 110 is in mechanical communication with a take-up reel 107r, which take-up reel 107r is operative to collect the flexible substrate 101 after the flexible substrate 101 has been embossed and cured, as described above.

The take-up shaft 107r may be connected to the drive unit 110 by using a drive belt 110b, which drive belt 110b will rotate D_RGiven the take-up shaft 107r, which in turn collects the flexible substrate thereon, the drive belt 110b will also drive the motion W_DImparting a flexible substrate 101 and an embossing belt 100. Although a drive belt 110b is depicted, any means for mechanically communicating the drive force may be used, including gears, direct drives, pulleys, drive shafts, and the like. For example, the driving unit 110 may be a motor.

One or more drive units 110 may be employed to impart the drive motion W_DAnd these drive units 110 may be connected to one or more components of the embossing apparatus 200, such as one or more transport rollers 103, so that the drive units 110 rotate the transport rollers 103, which transport rollers 103 in turn drive the movement W_DTo the flexible substrate 101 and to the embossing belt 100.

The compliant media 70 can be made of an optically transparent silicone-based elastomer material that is laminated to an optically transparent transfer adhesive layer, as described below with reference to FIGS. 1-37 b. Suitable materials for the silicone-based elastomer material (see reference numeral 44 in FIG. 22) include, but are not limited to, Polydimethylsiloxane (PDMS), DOW CORNING  silicone-based conformal coatings, including SYLGARD182  silicone elastomer, SYLGARD 183  silicone elastomer, SYLGARD 184  silicone elastomer, and SYLGARD186  silicone elastomer.

Optically transparent materials suitable for use in transferring the adhesive layer (see reference numeral 51 in FIG. 27) include, but are not limited to, Adhesives Research, Inc.  ARClear  DEV-8932 lightAnd (4) optically transparent silicone adhesive. For example, 25.0 μm thick (i.e., a seventh thickness t)₇25.0 μm) of arcclear  DEV-8932 sheet was used to transfer the adhesive layer 51.

The backing 81 can be an optically transparent material such that the ultraviolet light L can pass through the backing 81, the compliant media 70, and the imprint stamp 20 t. Suitable optically transparent materials for the tape 81 include, but are not limited to, mylar and mylar . Although the thickness of the belt liner 81 varies based on the application, a suitable range of the thickness of the belt liner 81 that produces a flexible belt when connected with the compliant media 70 is about 50.0 μm to 150.0 μm.

In an alternative embodiment of the present invention, as shown in FIGS. 40, 41 and 46, the embossing apparatus 200 includes an embossing drum instead of the embossing belt 100 described above. The embossing apparatus 200 includes a flexible substrate 101, a coating unit 300, and an embossing drum 90, the embossing drum 90 including an optically transparent cylinder 69 and an optically transparent compliant media 70, the compliant media 70 being connected to the cylinder 69. As described above, the compliant media 70 includes an optically transparent imprint stamp 20t having an imprint pattern 20q therein. Fig. 46 and 32 to 34b provide a more detailed view of the embossing drum 90 than fig. 40 and 41.

Also as described above, the drive unit 110 will drive the movement W_DTo the embossing drum 90 and the flexible substrate 101. The molding apparatus 200 may include the above-described mechanism for maintaining the constant distance D_cA supply reel 107s, and a take-up reel 107 t. The drive unit 110 may drive the take-up shaft 107t and/or one or more transport rollers 103. Alternatively, the embossing drum 90 may be driven by the driving unit 110; however, care should be taken to avoid slippage between the compliant media 70 and the flexible substrate 101.

A plurality of transfer rollers 103 are coupled to the bottom side 101b of the flexible substrate 101 and are operable to conformally wrap the coated side 101c around a portion of the embossing drum 90 such that the embossing drum 90 imparts a tension in the flexible substrate 101 and the tension creates a pressure between the flexible substrate 101 and the embossing drum 90. This pressure is operative to effect embossing of the imprint stamp 20t in the photopolymer material 301.

Drive movement W_DThe coated side 101c is transferred to the embossing drum 90 and the imprint stamp 20t is urged into contact with the coated side 101c such that the imprint pattern 20q is embossed in the photopolymer material 301 to form a replicate pattern 20u in the photopolymer material 301. In FIG. 46, the compliant media 70 forms the outer surface of the embossing drum 90 such that the coated side 101c contacts the compliant media 70 and the imprint stamp 20t as the flexible substrate 101 is transferred onto the wound portion of the embossing drum 90.

The ultraviolet light source 99 irradiates the replicate pattern 20u with ultraviolet light L that passes through the cylinder 69 and the imprint stamp 20 t. The irradiation of the replicate pattern 20u is performed simultaneously with the embossing of the replicate pattern 20 u.

As described above, the flexible substrate 101 may be opaque to the ultraviolet light L. In fig. 40, 41 and 46, the ultraviolet light source 99 may be located inside the embossing drum 90 or outside the embossing drum 90. If the ultraviolet light source 99 is located outside of the embossing drum 90, the intensity of the ultraviolet light source 99 is increased because the ultraviolet light L must pass through both layers of the cylinder 69 and the compliant media 70, and some attenuation of the ultraviolet light L may occur.

The ultraviolet light source 99 may include a reflector 99r as described above, and the reflector 99r may form a curing window C_w(see FIG. 46). The ultraviolet light source 99 may be a UVA light source and the ultraviolet light L may have a wavelength of about 300.0nm to about 400.0 nm.

The same materials as described above for the embossing belt 100 may be used for the embossing drum 90; however, the cylinder 69 may be an optically transparent material including, but not limited to, glass, plastic, and quartz.

The gravure coater and the micro gravure^TMA coater or a slot die coater may be used for the coating unit 300, the first thickness t of the photopolymer material 301_cMay be in the range of about 0.5 μm to about 1.0 μm.

The embossing belt 100 and the embossing drum 90 can be manufactured using the methods described below with reference to fig. 1 to 37 b.

In fig. 1 to 4, the master substrate 11 is patterned and etched to form an imprint pattern 20 therein. In FIG. 1, the master substrate 11 is coated with a material 155 that will serve as an etch mask. Material 155 may be a photoresist material commonly used in the microelectronics art. The mask 151 bearing the pattern 153 formed in the master substrate 11 is irradiated with light 154 that exposes a material 155 bearing the pattern 153.

In fig. 2, material 155 is developed to remove those portions of material 155 that were exposed to light 154. In FIGS. 2 and 3, the master substrate 11 is etched with an etching material to remove those portions of the master substrate 11 not covered by the material 155. Thus, in fig. 3, a plurality of imprint patterns 20p are formed in the master substrate 11. In FIG. 4, the imprint pattern 20p defines an imprint stamp 20 on the master substrate 11.

The imprint stamp 20 can include imprint patterns 20p that vary in all three dimensions of length, width, and height. In the cross-sectional view of FIG. 4 and the top plan view of FIG. 5, the imprint patterns 20p are in the width dimension d₀Height dimension h₀And a length dimension L₀Is changed. The actual dimensions of imprint pattern 20p will depend on the application and to a large extent on the lithography process used to pattern material 155. For example, if a prior art microelectronic lithographic process is used, the dimension (d)₀、h₀、L₀) May be on the submicron scale, i.e. less than 1.0 μm. For example, the imprint pattern 20p may be a nanoimprint pattern, which may have a size (d) of 100.0nm or less₀、h₀、L₀). Thus, the imprint stamp 20 becomes to have a dimension (d) with a nanometer size₀、h₀、L₀) The imprint pattern 20 p.

Photolithographic processes well known in the microelectronics art can be employed to pattern and etch the master substrate 11. For example, a photolithographic process using a photoresist of the material 155 and an etching process such as Reactive Ion Etching (RIE) can be used to form the imprint stamp 20 in the master substrate 11.

Suitable materials for the master substrate 11 include, but are not limited to, silicon (Si) substrates and silicon (Si) wafers. In FIG. 5, the master substrate 11 is a silicon wafer having a wafer plane 11F. Four imprint stamps 20 are formed in the master substrate 11. The silicon wafer may be of any size. For example, a 4.0 inch silicon wafer is used as the master substrate 11 for the four imprint stamps 20. Larger diameter silicon wafers (e.g., 8 inches or 12 inches) may be used to provide a larger surface area for multiple imprint stamps 20 or for larger imprint stamps 20. Although the imprint patterns 20p are the same as in FIG. 5, the imprint stamp 20 can include imprint patterns 20p that vary (i.e., are not the same) therein.

In fig. 6, the release layer 13 is deposited over the imprint patterns 20 p. The release layer 13 comprises a first thickness t₁Which in operation conformally coats the imprint pattern 20p such that the first thickness t₁The thickness is substantially the same on both vertical and horizontal surfaces of the imprint pattern 20 p. Suitable materials for the release layer 13 include, but are not limited to, fluorocarbon materials. As an example, the fluorocarbon material of the release layer 13 may employ trifluoromethane (CHF) for about 5.0 minutes₃) Plasma deposition of gases.

A first thickness t₁Depending on the application; however, as discussed below, the release layer 13 is operative to provide a non-blocking surface to which a silicone-based elastomer material is applied which is subsequently released from the release layer 13. Thus, the release layer 13 may be a very thin layer having a first thickness t of about 50.0nm to about 150.0nm thick₁。

In FIG. 7, the silicone-based elastomer layer 15 is deposited over the release layer 13 to a first depth d₁Which completely covers the imprint pattern 20 p. To obtain a silicone-based elastomer layer 15 of uniform thickness, the master substrate 11 should be relatively flat. This can be achieved, for example, by placing the master substrate 11 on a horizontal surface or horizontal vacuum chuck prior to depositing the silicone-based elastomer layer 15.

The silicone-based elastomer layer 15 is then cured by heating H the master substrate 11. Curing may be accomplished by drying the master substrate 11 at a predetermined temperature for a predetermined period of time. The actual time and temperature will depend on the application and also on the type of material used for the silicone-based elastomer layer 15. Suitable materials for the silicone-based elastomer layer 15 include, but are not limited to, Polydimethylsiloxane (PDMS), DOW CORNING  silicone-based conformal coatings, including SYLGARD182  silicone elastomer, SYLGARD 183  silicone elastomer, SYLGARD 184  silicone elastomer, and SYLGARD186  silicone elastomer.

The first depth d of the silicone-based elastomer layer 15₁And may be application dependent. However, in a preferred embodiment, the silicone-based elastomer layer 15 has a first depth d₁From about 0.5mm to about 1.5 mm. In the case of PDMS or DOW C0RNING  SYLGARD  silicone-based elastomers, curing of the silicone-based elastomer layer 15 may be accomplished by drying the master substrate 11 in an oven or the like. The predetermined temperature and the predetermined time for curing may be about 100.0 ℃ for about 4.0 hours.

In an alternative embodiment, also shown in FIG. 6, in the curing step described above, having a second thickness t₂Is applied to the deposited silicone-based elastomer layer 15. Preferably, the cover layer 16 is a polyester film and the second thickness t₂From about 50.0 μm to about 150.0 μm. The cover layer 16 may be used to planarize any surface irregularities in the silicone-based elastomer layer 15 that cause deviations from the substantially planar surface 15s of the silicone-based elastomer layer 15.

After the curing step, the complementary image 20r of the imprint pattern 20p is replicated in the silicone-based elastomer layer 15, such that the imprint stamp 20a is formed in the silicone-based elastomer layer 15 (see FIGS. 8-10).

In fig. 7, the silicone-based elastomer layer 15 is detached from the release layer 13 after the curing step. The silicone-based elastomer layer 15 may be separated from the release layer 13 using the tip of a pair of tweezers or a knife or the edge of a razor blade such as an X-Acto  knife, as indicated by the knife edge K inserted between the silicone-based elastomer layer 15 and the release layer 13 along the dashed arrow. The silicone-based elastomer layer 15 may be removed from the release layer 13 by grasping an edge of the silicone-based elastomer layer 15 and peeling the silicone-based elastomer layer 15 away from the release layer 13 (see dashed arrow P). If the cover layer 16 is used, the cover layer 16 is removed from the silicone-based elastomer layer 15 before the silicone-based elastomer layer 15 is released from the release layer 13.

In FIGS. 8, 9, and 10, the imprint stamp 20a is removed from an excess portion of the silicone-based elastomer layer 15 surrounding the imprint stamp 20 a. If the cover layer 16 described above is used, the imprint stamp 20a is removed from the excess portion of the silicone-based elastomer layer 15 and the cover layer 16 surrounding the imprint stamp 20 a.

In either case, the imprint stamp 20a can be removed from the excess portion by placing the silicone-based elastomer layer 15 on the substantially flat substrate 21 and then cutting at the perimeter C (see dashed lines in FIGS. 8 and 9) of the imprint stamp 20a to remove the excess portions of the silicone-based elastomer layer 15 or the silicone-based elastomer layer 15 and the cover layer 16 from the imprint stamp 20 a. The cutting may be accomplished with a knife, razor, clamp, or the like, as shown by knife K in fig. 9. After the imprint stamp 20a has been released, the excess portions (15 or 15 and 16) can be peeled away from the substantially planar substrate 21 such that the imprint stamp 20a is no longer connected to the excess portions (see FIG. 10). The substantially planar substrate 21 may be a material including, but not limited to, glass, metal, plastic, or quartz. For example, the substantially planar substrate 21 may be a glass plate.

Alternatively, the above steps may be repeated as necessary to create additional imprint stamps 20a using the master substrate 11. One advantage of the method of the present invention is that the master substrate 11 is not damaged by the above-described process steps. Thus, the same master substrate 11 can be reused to produce several imprint stamps 20 a. Thus, the cost of patterning and etching the master substrate 11 and depositing the release layer 13 can be amortized over several imprint stamps 20 a.

Another advantage of the method of the present invention is that the master substrate 11 does not have to be cleaned after each use in order to remove contaminants such as dust particles, since the silicone-based elastomer layer 15 flows over the particles and entrains them. Thus, the master substrate 11 is self-cleaning in that particles are removed by the silicone-based elastomer layer 15.

In fig. 11, has a third thickness t₃Is set to have a fourth thickness t₄On a flat and compliant silicone rubber backing 31. Suitable materials for the thin plastic film 33 include, but are not limited to, polyimide and polyester (PET, polyethylene terephthalate). Third thickness t₃And a fourth thickness t₄Depending on the application. Preferably, the third thickness t of the thin plastic film 33₃About 40.0 μm to about 100.0 μm, and a fourth thickness t of the silicone rubber backing 31₄From about 0.125 inches to about 0.25 inches. Fourth thickness t of silicone rubber backing 31₄Should be selected to ensure that the silicone rubber backing 31 is compliant (i.e. not stiff).

In fig. 12, a surface 33s of a thin plastic film 33 is coated with a photopolymer solution 35. The photopolymer solution 35 can include, but is not limited to, a mixture of about 50% of a photopolymer material and about 50% acetone. As will be described below, the acetone evaporates to leave a solid photopolymer layer on the surface 33s of the thin plastic film 33. Photopolymer materials can include, but are not limited to, Norland that cures upon UV exposure^TMAn optical adhesive. Preferably, the photopolymer material will cure in a time of about 5.0 seconds to about 60.0 seconds. For example, Norland  NOA 83H photopolymer can be used for the photopolymer solution 35.

In fig. 13 and 14, a photopolymer solution 35 is spread on a surface 33s of a thin plastic film 33 to form a film having a fifth thickness t₅The photopolymer layer 35. Preferably, the photopolymer solution 35 is spread by using a Mayer bar M₁Realized by winding a wire W with a first diameter₁. Mayer bar M₁Slide over the surface 33s (S) and measure the photopolymer solution 35, thus forming a film having a fifth thickness t₅By photopolymerizationLayer 35. Any acetone in the photopolymer solution 35 substantially evaporates during the spreading process. Thus, the photopolymer layer 35 substantially comprises a photopolymer material as described above. Preferably, the fifth thickness t of the photopolymer layer 35₅From about 5.0 μm to about 10.0 μm. The first diameter of wire W1 is application specific. Preferably, the first diameter of the wire W1 is about 50.0 μm to about 100.0 μm.

In FIG. 15, the patterning surface 21a of the imprint stamp 20a is disposed on the photopolymer layer 35. By placing the imprint stamp 20a over the photopolymer layer 35, one can include bringing the edge e1 of the imprint stamp 20a into contact with the photopolymer layer 35 and pressing against the edge e1 while gradually lowering the other portions of the patterning surface 21a (see arrows L1 and d) into contact with the photopolymer layer 35. A pair of forceps or suction wand may be used to grasp edge e2, thereby lowering and pressing against edge e 2. Alternatively, the pattern forming surface 21a may be brought into contact with the photopolymer layer 35 using a rubber roller or the like while being gradually lowered.

One advantage of the gradual lowering is that air trapped between the photopolymer layer 35 and the patterning surface 20r moves so that air bubbles that can create defects are not trapped between the photopolymer layer 35 and the patterning surface 20 r.

Another advantage of the method of the present invention is that once the imprint stamp 20a has been placed on the photopolymer layer 35, the imprint stamp 20a can be floated (see dashed line F) over the surface 35s of the photopolymer layer 35 to position the imprint stamp 20a at a predetermined location on the photopolymer layer 35. The floating F can be achieved manually using tweezers or suction sticks or can be automated, and a precision mechanical device, such as a robotic end effector, can be used to precisely position the imprint stamp 20 a.

In FIG. 16, the photopolymer layer 35 is cured to fix the position of the imprint stamp 20a on the photopolymer layer 35 and to transfer the image of the imprint pattern 20r to the photopolymer layer 35. The photopolymer layer 35 is cured by irradiating the photopolymer layer 35 with ultraviolet UV light having a predetermined intensity for a first period of time. The photopolymer layer 35 hardens as it cures and the image of the imprint pattern 20r transferred into the photopolymer layer 35 also hardens and is fixed in the photopolymer layer 35 as an imprint pattern 20 s.

The ultraviolet light UV may have a wavelength including, but not limited to, about 300.0nm to about 400.0 nm. The predetermined intensity of the ultraviolet light UV may include, but is not limited to, about 150mW/cm²The strength of (2). The first period of time may include, but is not limited to, a time of about 5.0 seconds to about 60.0 seconds. For example, the ultraviolet light UV can be from a UVA ultraviolet light source.

Yet another advantage of the method of the present invention is that the imprint stamp 20a used to pattern the photopolymer layer 35 can have a thickness that can vary (see t in FIG. 16)_AAnd t_B) And these variations in thickness do not affect the accuracy with which the imprint pattern 20r is transferred to the imprint pattern 20s of the photopolymer layer 35. Thickness (t)_AAnd t_B) May be due to variations in the method used to make the imprint stamp 20a, variations in the first depth d1 of FIG. 7, or the use of different master substrates 11 to make different imprint stamps 20 having different imprint patterns 20 p.

After the curing step, in FIGS. 17 and 18, the imprint stamp 20a is removed (P) from the photopolymer layer 35 such that the image of the imprint pattern 20r defines a photopolymer shim 36 having an imprint pattern 20s fixed therein. The imprint stamp 20a can be removed (P) using a pair of tweezers or the like to grasp the edge (e1 or e2) and then lift the imprint stamp 20a from the photopolymer layer 35 (see dashed line P).

In fig. 19, the photopolymer shim 36 is then cured by heating. Post-curing of the photopolymer shim 36 can include, but is not limited to, a time of about 1.0 hour at a temperature of about 100 ℃. Optionally, after the post-curing step, the photopolymer shim 36 may be rinsed with an acetone solution to remove chemical species that may prevent curing of the silicone-based elastomer material, such as PDMS or SYLGARD  silicone-based elastomer material described above. Post-curing of the photopolymer shim 36 isolates the cure-inhibiting species and improves the adhesion of the photopolymer shim 36 to the thin plastic film 33.

In FIG. 19, after post-curing of the photopolymer shim 36, has a sixth thickness t₆Is deposited on the photopolymer shim 36. A sixth thickness t₆And may include, but is not limited to, a thickness of about 50.0nm to about 150.0 nm. As one example, fluorocarbon material 37 may utilize trifluoromethane (CHF) for approximately 5.0 minutes₃) Plasma deposition of gases.

Also in fig. 19, after deposition of the fluorocarbon material 37, the knife edge of a tweezer or knife may be inserted between the thin plastic film 33 and the silicone rubber backing 31, and the thin plastic film 33 may be peeled off the silicone rubber backing 31, as shown by the dashed line P. Hereinafter, the combination of the photopolymer shim 36 and the thin plastic film 33 will be referred to as the photopolymer shim 36 unless otherwise noted.

In fig. 20, after the thin plastic film 33 is separated, a photopolymer shim 36 is applied to a support substrate 41. The photopolymer shim 36 can be attached to the support substrate 41 by placing the photopolymer shim 36 on the support substrate 41 and securing one end of the photopolymer shim 36 to the support substrate 41 with an adhesive. For example, a high-temperature adhesive tape T may be used. The support substrate 41 may be made of a material including, but not limited to, glass and quartz.

In fig. 21 and 22, has a first height h₁Is fixed to the support base 41. For example, the spacer pieces 43 may be attached to the support substrate 41 using an adhesive, such as the high temperature adhesive tape T described above. The spacer block 43 is positioned adjacent to the photopolymer shim 36 and is spaced a first distance D from the photopolymer shim 36₁So that a space exists between the spacer block 43 on the surface 41s of the support substrate 41 and the photopolymer shim 36. First height h of shim stock 43₁Should exceed the height hs of the photopolymer shim 36 shown in FIG. 22. First height h₁And a first distance D₁Depending on the application; however, the first height h₁Can be treatedIn a range including, but not limited to, about 0.5mm to about 1.5mm, and a first distance D₁May be in the range including, but not limited to, about 1.0mm to about 2.0 mm. The shim stock 43 may be a material including, but not limited to, metal, glass, quartz, and stainless steel. For example, the shim stock 43 may be a stainless steel shim stock, the first height h₁May be about 0.5 mm.

In FIG. 21, the support substrate 41 is preheated (H) to increase the temperature of the support substrate 41 in preparation for coating the shim stock 43 and the photopolymer shim 36 with a silicone-based elastomer material, as will be discussed below. Preferably, the silicone-based elastomer material is not coated on a cold or room temperature (i.e., from about 18.0℃ to about 28.0℃) support substrate 41. The temperature at which the support substrate 41 is preheated will depend on the application and should not exceed the temperature limit of the photopolymer shim 36. For example, the support substrate 41 may be preheated to a temperature of about 100 ℃. The temperature of about 100 c is below the temperature limit of most photopolymer materials.

In fig. 22 and 23, the photopolymer shim 36 and the shim stock 43 are coated with a compliant material 44 that completely covers the photopolymer shim 36 and the shim stock 43 (see fig. 22). Suitable materials for the compliant material 44 include, but are not limited to, silicone-based elastomeric materials and amorphous fluoropolymer materials.

Suitable silicone-based elastomeric materials include, but are not limited to, Polydimethylsiloxane (PDMS), DOW CORNING  silicone-based conformal coatings, including SYLGARD182  silicone elastomer, SYLGARD 183  silicone elastomer, SYLGARD 184  silicone elastomer, and SYLGARD186  silicone elastomer. Preferably, the PDMS is a mixture of about 10.0 parts of a base material and about 1.5 parts of a curing agent. When they have the same density, the base material and the curing agent may be mixed by weight or volume.

Suitable materials for the amorphous fluoropolymer material include, but are not limited to, TEFLON  AF. For example, DuPont^TMTEFLON  AF may be used for the compliant material 44. When the compliant material 44 comprises an amorphous fluoropolymer material, it need not beThe preheating step in fig. 21 is described.

In FIGS. 23 and 24, a compliant material 44 is spread over the photopolymer shim 36 and the shim stock 43 to form a compliant media 45 that covers the photopolymer shim 36 and the shim stock 43 (see thickness t in FIG. 24)₈And t₉). The imprint pattern 20s in the photopolymer shim 36 is transferred to the compliant media 45 such that the imprint stamp 20t is formed in the compliant media 45.

Preferably, the distribution of the compliant material 44 is by a Mayer bar M₂By the implementation of the Mayer bar M₂Wound with a wire W having a second diameter₂. Mayer bar M₂The compliant material 44 is slid over the shim stock 43(S) and measured to form a compliant media 45 that is uniform and smooth in thickness. The compliant material 44 is at a thickness t₈Covering the spacer block 43 by a thickness t₉Covering the photopolymer shim 36, wherein t₉＞＞t₈. Mayer bar M₂Wound with a diameter greater than that of the Mayer rod M₁Much thicker diameter wires. Wire W₂Depending on the application. Preferably, the wire W₂Is about 1.0mm to about 3.0 mm. For example, it can be found in Mayer bar M₂A wire with a diameter of about 1.5mm is wound on the upper portion.

After the spreading, the support substrate 41 is heated (H). The surface 41s, in operation, provides a surface to which the portion 45c of the compliant media 45 adheres during and after the heating step. The time and temperature at which the substrate 41(H) is heated depends on the application, and as previously mentioned, the temperature must not exceed the temperature limits of the photopolymer shim 36 or the compliant media 45. As one example, when the compliant media 45 is made of a silicone-based elastomer material, the support substrate 41 can be heated at a temperature of about 100.0 ℃ for about 4.0 hours (H). Heating H cures the silicone-based elastomer material. Alternatively, when the compliant media is made of an amorphous fluoropolymer material, the support substrate 41 can be heated at a temperature of about 60.0 ℃ for about 4.0 hours (H). In this case, heating H evaporates the amorphous fluoropolymer material to dryness.

After the heating step, the support substrate 41 is cooled down. Preferably, the support substrate 41 is allowed to cool to a temperature of about room temperature (i.e., about 18.0 ℃ to about 28.0 ℃).

After the support substrate 41 has cooled, the spacer pieces 43 are removed from the support substrate 41. In FIG. 24, the shim stock 43 can be removed by cutting the compliant media 45(K) along the edge of the shim stock 43 proximate to the photopolymer shim 36. A knife, razor, or the like may be used to cut the compliant media 45 (K). After cutting the compliant media 45(K), the shim stock 43 can be peeled away from the support substrate 41. The edge of the shim stock 43 (see dashed line for K) is applied as a guide for performing the cut K because the portion 45c of the compliant media 45 adheres to the surface 41s of the support substrate 41 and the adhesion prevents the compliant media 45 from prematurely separating from the substrate 41.

In fig. 25 to 27, the first adhesive surface a of the transfer adhesive layer 51₁Is applied to the surface 45s of the compliant media 45 such that the transfer adhesive layer 51 adheres to the compliant media 45. The transfer adhesive layer 51 includes a seventh thickness t as described below₇And a second adhesive surface A₂。

In fig. 25, a first adhesive surface a₁May be applied by peeling the primary backing 53 away from the transfer adhesive layer 51 (P) prior to application to the surface 45s₁) And is exposed. Likewise, the second adhesive surface A₂The adhesive layer 51 can be peeled off (P) by peeling the secondary backing 55 from the transfer adhesive layer₂) And is exposed. First adhesive surface A₁May be attached to the surface 45s by using a roller 59 (see fig. 26).

In FIG. 26, the first bonding surface is at the edge of the compliant media 45 and the roller 59 rolls onto the secondary backing 55 to gradually bring the first bonding surface A₁Is applied to the surface 45s until the entire surface 45s is bonded to the first bonding surface A₁Connected (see fig. 27). The roller 59 may be, for example, a rubber roller. The roller 59 allows the first adhesive surface A₁Is applied to the surface 45s without trapping the first adhesive surface A₁And the surface 45 s.

A seventh thickness t of the transfer adhesive layer 51₇Depending on the application. However, because the transfer adhesive layer 51 is still attached to the compliant media 45, and because it is desirable that the compliant media 45 be flexible, the transfer adhesive layer 51 should be as thin as possible. Preferably, the seventh thickness t of the transfer adhesive layer 51₇Is about 20.0 μm to about 100.0 μm thick.

Preferably, the transfer adhesive layer 51 is an optically transparent material such that another photopolymer material that is in contact with the compliant media 45 and the imprint stamp 20t can be cured by a light source incident on the transfer adhesive layer 51 and the compliant media 45, as will be described below.

Optically transparent materials suitable for use in transfer adhesive layer 51 include, but are not limited to, AdhesivesResearch, Inc.^TM ARc1ear^TMDEV-8932 is an optically clear silicone adhesive. For example, 25.0 μm (i.e., a seventh thickness t) may be formed₇25.0 μm) thick clearer^TMThe DEV-8932 sheet was used to transfer the adhesive layer 51.

In FIG. 28, the compliant media 45 can be separated from the support substrate 41 by using a knife, razor, suction wand, tweezers, or the like to separate the compliant media 45 from the support substrate 41, as shown by knife K. In FIG. 29, an example of a feature (i.e., pattern) that includes the imprint stamp 20t is depicted in greater detail. In FIG. 30, after peeling, the compliant media 45 is still attached to the photopolymer shim 36 and the thin plastic film 33.

An additional advantage of the method of the present invention is that the photopolymer shim 36 and the layer of thin plastic film 33 protect the imprint stamp 20t from damage during subsequent processing steps described below with reference to FIGS. 31 through 37 b. These processing steps may be completed, followed by peeling the photopolymer shim 36 and the layers of thin plastic film 33 to expose the imprint stamp 20 t. Because the multiple layers of the photopolymer shim 36 and the thin plastic film 33 will eventually separate from the compliant media 45 in order to expose the imprint stamp 20t carried by the compliant media 45, hereinafter, the combination of the multiple layers including the photopolymer shim 36 and the thin plastic film 33 will be referred to as a photopolymer shim (see FIG. 30) unless otherwise noted.

Also, because the transfer adhesive layer 51 is still connected with the compliant media 45, the combination of the compliant media 45 and the transfer adhesive layer 51 is denoted as the compliant media 70. In FIGS. 28 and 30, the combination of the compliant media 70 and the photopolymer shim 36 is represented as a compliant assembly 75. The compliant assembly 75 is connected to a cylinder and a flexible belt liner as will be described below.

In fig. 31a, 31b and 31c, there is an L-shaped clamp 73 comprising a horizontal portion 73h and a vertical portion 73v, the vertical portion 73v forming a low vertical wall. The horizontal and vertical portions (73h, 73v) are at a right angle beta to each other. The portions (73h, 73v) should be smooth and substantially flat. An L-clamp 73 can be used to laminate the compliant assembly 75 to the surface 69s of the cylinder 69.

In fig. 31a and 31b, the support substrate 41 may be located on the horizontal portion 73h and against the vertical portion 73 v. Alternatively, if the compliant assembly 75 has been separated from the support substrate 41, a bed (not shown) made of a smooth, flat piece of silicone rubber can be placed on the horizontal portion 73h with one end of the bed abutting the vertical portion 73 v. The compliant assembly 75 is located on top of the bed and is aligned with the vertical portion 73v by using the vertical portion 73v as a vertical straight edge. If the secondary backing 55 is still on the transfer adhesive layer 51, the secondary backing 55 may be peeled off (P)₂) Thereby exposing the second adhesive surface A₂。

In fig. 31a and 31c, a cylinder 69 having an outer surface 69s is aligned with the horizontal portion 73h and the vertical portion 73v such that the outer surface 69s is tangent (73t) to these portions (73h, 73 v). The cylinder 69 is lowered onto the compliant assembly 75 such that the second adhesive surface A2 contacts a portion of the outer surface 69s at the tangent point 73 t. The cylinder 69 is then rolled in the roll direction R_DThe roll (R) collects the compliant assembly 75 on the outer surface 69s as the cylinder 69 rolls (R). After the compliant assembly 75 is rolled onto the cylinder 69, there will be a gap 70g between the adjacent ends of the compliant assembly 75, as shown in FIG. 31 b.

Suitable materials for the cylinder 69 include, but are not limited to, metals, ceramics, glass, quartz, and plastics. Preferably, the cylinder 69 is made of an optically transparent material such that the light L can pass through the cylinder 69, the compliant media 70, and the imprint stamp 20 t. Suitable optically transparent materials for the cylinder 69 include, but are not limited to, glass, quartz, and plastic. In FIG. 32, a light source 99, such as an ultraviolet light source, can be positioned inside or outside the cylinder 69 to irradiate and cure the photopolymer material (not shown) that is urged into contact with the imprint stamp 20 t. Because the compliant media 70 can be made to any size, the cylinder 69 can include an inner diameter sufficient to accommodate the light source 99. Alternatively, the light source 99 may be small enough to fit within the inside diameter of the cylinder 69.

In FIG. 31b, an alternative method of connecting the compliant media 45 to the cylinder 69 is depicted. The compliant media is shown as 45 instead of 70 because the transfer adhesive layer 51 is not connected to the compliant media 45 in FIG. 31 b. First, the first adhesive surface a of the transfer adhesive layer 51 is exposed by peeling off the first backing 53 (not shown)₁. Next, the outer surface 69s of the cylinder 69 is bonded to the first bonding surface A₁Attached, the cylinder 69 is then rolled to collect the transfer adhesive layer 51 on the outer surface 69 s. Again, a portion of the secondary backing 55 is peeled away to expose the second adhesive surface A₂A part of (a). Next, the second adhesive surface A₂Is connected with the compliant media 45 at a tangent point 73t, and the cylinder 69 is in the roll direction R_DThe roll is rolled to collect the compliant media 45 on the cylinder 69 while peeling away the remaining portion (55p) of the secondary backing 55 to expose the second adhesive surface A₂The remainder of (a).

In FIGS. 32 and 33, after the compliant assembly 75 has been rolled onto the cylinder 69, there may be an excess portion 75x of the compliant assembly 75 that must be trimmed so that a majority of the compliant assembly 75 can be smoothly rolled onto the cylinder 69. As mentioned above, if there is a gap 70g, it is desirable to trim the excess portion 75x so that the gap 70g is as small as practicable. A knife K or the like can be used to trim the excess portion 75 so that the compliant assembly 75 is located on the outer surface 69s without protrusions. In fig. 33, the knife K can be along the direction K_dCutting to thereby realizeTrimming of the excess 75x to form a fully laminated roller 90. In FIG. 33, the imprint stamps 20t are shown in dashed outline because they are still located beneath the photopolymer shim 36 that is not separated from the compliant media 70.

The line n-n through the cylinder 69 and the compliant assembly 75 in FIG. 33 is shown in greater detail in the cross-sectional views of FIGS. 34a and 34 b. In FIG. 34a, the compliant assembly 75 is shown prior to trimming the excess 75 x. In FIG. 34b, the compliant assembly 75 is shown after the excess 75x has been trimmed.

In FIG. 34a, the excess portion 75x includes the compliant media 70 and the photopolymer shim 36. Because the thin plastic film 33 (see FIG. 28) associated with the photopolymer shim 36 can be opaque to light and the photopolymer shim 36 can be optically transparent, the photopolymer shim 36 can be peeled away as indicated by the dashed arrow P so that the compliant media 70 (i.e., the optically clear adhesive 51 and the optically clear compliant media 45) can be viewed along the edges Es of the compliant assembly 75, which compliant assembly 75 has been attached to the outer surface 69s of the cylinder 69.

A small edge K along the line of sight of the edge Es (see dashed line) may be used to cut the excess 75x so that the unconnected layers of the excess 75x are aligned with their corresponding connected layers, i.e.: 36 ' pair 36, 45 ' pair 45, 51 ' pair 51, as shown in fig. 34 a. After trimming, a small gap 70g can exist between adjacent ends of the compliant assembly 75.

In FIG. 34b, without the gap 70g, the compliant assembly 75 forms an almost continuous layer on the outer surface 69s of the cylinder 69. After trimming, the photopolymer shim 36 can be peeled away (P) to expose the imprint stamp 20t on the compliant media 70.

In FIGS. 35 and 36, the compliant assembly 75 is applied to a belt backing 81. Prior to applying the compliant assembly 75 to the tape backing 81, the secondary backing 55 is peeled away from the transfer adhesive layer 51 to expose the second adhesive surface A₂. Then, the second bonding surface A is gradually bonded₂Is applied to the surface 81s of the belt material 81. One roller 89, such as a rubber roller, may be used in the roll direction R_DThe compliant assembly 75(R) is rolled.

The roll R can begin at a first end (75a, 81a) and end at a second end (75b, 81b) of the compliant assembly 75 and the belt liner 81. After the compliant assembly 75 and the belt liner 81 are attached to each other (see FIG. 36), the first and second ends (81a, 81b) can be joined to form a belt 100, as shown in FIGS. 37a and 37 b. As described above, the gap 70g may separate the first and second ends (75a, 75 b). An adhesive tape or the like may be used to cover the gap 70 g. A piece of adhesive tape 81t may also be used to join the first and second ends (81a, 81b) of the tape backing 81 to form the tape 100. After the belt 100 is formed, the layers 71 (i.e., 33 and 36) can be peeled apart (P) to expose the imprint stamp 20t on the compliant media 70. Suitable adhesive tapes include, but are not limited to, high temperature silicone based tapes.

The backing 81 can be an optically transparent material such that the light L can pass through the backing 81, the compliant media 70, and the imprint stamp 20 t. Optically transparent materials suitable for tape backing 81 include, but are not limited to, DuPont^TMMylar film . For example, a light source 99, such as an ultraviolet light source, can be positioned inside or outside the belt 100 to irradiate and cure a photopolymer material (not shown) that is urged into contact with the imprint stamp 20 t. The tape backing 81 may have a thickness t of about 50.0 μm to about 150.0 μm_B。

Although several embodiments of the apparatus and method of the present invention have been disclosed and illustrated herein, the invention is not to be limited to the specific forms or arrangements of parts so described and illustrated. The invention is limited only by the claims.

Claims

1. A molding apparatus (200), comprising:

a flexible substrate (101) comprising a coated side (101c) and a bottom side (101 b);

a coating unit (300) for coating the substrate with a first thickness (t)_c) Is deposited on the coated side (101 c);

an embossing belt (100) comprising an optically transparent belt liner (81) and an optically transparent compliant media (70) coupled to the belt liner (81), the compliant media (70) including an optically transparent imprint stamp (20t) having an imprint pattern (20q) therein;

a plurality of transport rollers (103) connected to the belt liner (81) and supporting the embossing belt (100) in operation;

a drive unit (110) for driving the movement (W)_D) To an embossing belt (100) and a flexible substrate (101);

a backing roll (105) encased by a portion of the bottom surface (101b) and a portion of the compliant media (70) to impart a tension to the embossing belt (100) and the tension creates a pressure between the flexible substrate (101) and the embossing belt (100);

the driving movement (W)_D) In operation, transporting the bottom surface (101b) onto a support drum (105) and urging the imprint stamp (20t) and the coated surface (101c) into contact with each other, thereby embossing the imprint pattern (20q) in the photopolymer material (301) and forming a replicate pattern (20u) in the photopolymer material (301); and

an ultraviolet light source (99) for irradiating the replicate pattern (20u) with ultraviolet light (L) through the belt material (81) and the imprint stamp (20t) simultaneously with embossing of the replicate pattern (20 u).

2. The embossing apparatus (200) as set forth in claim 1, wherein the flexible substrate (101) is opaque to the ultraviolet light (L).

3. The embossing apparatus (200) as set forth in claim 1, wherein the ultraviolet light source (99) has a position relative to the embossing belt (100) selected from a position inside the embossing belt (100) and a position outside the embossing belt (100).

4. The embossing apparatus (200) as set forth in claim 1, wherein the ultraviolet light source (99) comprises a UVA ultraviolet light source.

5. The embossing apparatus (200) of claim 1, wherein the ultraviolet light (L) includes a wavelength of about 300.0 nanometers to about 400.0 nanometers.

6. The embossing apparatus (200) as set forth in claim 1, wherein the coating unit (300) comprises a coater selected from the group consisting of a gravure coater, a micro gravure coater, and a slot die coater.

7. The embossing apparatus (200) of claim 1, wherein the first thickness (t) of the photopolymer material (301) is greater than the second thickness (t)_c) In the range of about 0.05 microns to about 2.0 microns.

8. Embossing device (200) according to claim 1, characterized in that at least one transport roller (103) is connected to the drive unit (110), and in that the drive unit (110) rotates the transport roller (103) in operation to impart the drive movement (W)_D) To an embossing belt (100) and a flexible substrate (101).

9. The embossing apparatus (200) of claim 1, further comprising: a supply reel (107s) for carrying the flexible substrate (101) and dispensing the flexible substrate (101) to the coating unit (300).

10. The embossing apparatus (200) of claim 1, further comprising: a take-up reel (107r) for collecting the flexible substrate (101) after the flexible substrate (101) has been embossed and cured.

11. Embossing apparatus (200) as claimed in claim 10, characterized in that the take-up shaft (107r) is connected to a drive unit (110), and the drive unit (110) rotates (D) in operation_R) A take-up reel (107r) to collect the flexible substrate (101) and to transmit the drive motion (W)_D)。

12. The embossing apparatus (200) as set forth in claim 1, wherein the compliant media (70) includes an optically transparent silicone-based elastomer material (44) laminated to an optically transparent transfer adhesive layer (51).

13. The embossing apparatus (200) as set forth in claim 12, wherein the optically transparent silicone-based elastomer material (44) is a material selected from the group consisting of polydimethylsiloxane, SYLGARD182, SYLGARD 183, SYLGARD 184, and SYLGARD 186.

14. The embossing apparatus (200) as set forth in claim 12, wherein the optically transparent transfer adhesive layer (51) is an arcclear DEV-8932 optically transparent silicone adhesive.

15. The embossing apparatus (200) as set forth in claim 1, wherein the optically transparent strip liner (81) is a material selected from the group consisting of mylar and mylar.

16. The embossing apparatus (200) of claim 1, wherein the ultraviolet light source (99) further includes a reflector (99r) for focusing the ultraviolet light (L) at a location where the imprint stamp (20t) is urged into contact with the coated side (101c) so that the photopolymer material (301) is not cured before the imprint pattern (20q) is embossed in the photopolymer material (301).

17. A molding apparatus (200), comprising:

an embossing drum (90) comprising an optically transparent cylinder (69) and an optically transparent compliant media (70) coupled to the cylinder (69), the compliant media (70) including an optically transparent imprint stamp (20t) having an imprint pattern (20q) therein;

a drive unit (110) for driving the movement (W)_D) Transferred to the embossing drum (90) and to the flexible substrate (101);

a plurality of transfer rollers (103) coupled to the bottom surface (101b) and operable to conformally wrap the coated side (101c) around a portion of the embossing drum (90) such that the embossing drum (90) imparts a tension to the flexible substrate (101) and the tension creates a pressure between the flexible substrate (101) and the embossing drum (90);

the driving movement (W)_D) In operation, transporting the coated side (101c) onto an embossing drum (90) and urging the imprint stamp (20t) and the coated side (101c) into contact with each other, thereby embossing the imprint pattern (20q) in the photopolymer material (301) and forming a replicate pattern (20u) in the photopolymer material (301); and

an ultraviolet light source (99) for irradiating the replicate pattern (20u) with ultraviolet light (L) through the cylinder (69) and the imprint stamp (20t), the irradiating being simultaneous with embossing of the replicate pattern (20 u).

18. The embossing apparatus (200) as set forth in claim 17, wherein the flexible substrate (101) is opaque to the ultraviolet light (L).

19. The embossing apparatus (200) as set forth in claim 17, wherein the ultraviolet light source (99) has a position relative to the embossing drum (90) selected from a position interior to the embossing drum (90) and a position exterior to the embossing drum (90).

20. The embossing apparatus (200) as set forth in claim 17, wherein the ultraviolet light source (99) comprises a UVA ultraviolet light source.

21. The embossing apparatus (200) of claim 17, wherein the ultraviolet light (L) includes a wavelength of about 300.0 nanometers to about 400.0 nanometers.

22. The embossing apparatus (200) as set forth in claim 17, wherein the coating unit (300) comprises a coater selected from the group consisting of a gravure coater, a micro gravure coater, and a slot die coater.

23. Embossing device (200) according to claim 17, characterized in that the first thickness (t) is greater than the second thickness (t;)_c) In the range of about 0.05 microns to about 2.0 microns.

24. Embossing device (200) according to claim 17, characterized in that at least one transport roller (103) is connected to the drive unit (110), and in that the drive unit (110) rotates the transport roller (103) in operation to impart the drive movement (W)_D) To the embossing drum (90) and to the flexible substrate (101).

25. The embossing apparatus (200) of claim 17, further comprising: a supply reel (107s) for carrying the flexible substrate (101) and dispensing the flexible substrate (101) to the coating unit (300).

26. The embossing apparatus (200) of claim 17, further comprising: a take-up reel (107r) for collecting the flexible substrate (101) after the flexible substrate (101) has been embossed and cured.

27. The embossing apparatus (200) according to claim 26, wherein the take-up shaft (107r) is connected to a drive unit (110), and the drive unit (110) rotates (D) in operation_R) A take-up reel (107r) to collect the flexible substrate (101) and to drive the movement (W)_D) To the embossing drum (90) and to the flexible substrate (101).

28. The embossing apparatus (200) as set forth in claim 17, wherein the compliant media (70) includes an optically transparent silicone-based elastomer material (44) laminated to an optically transparent transfer adhesive layer (51).

29. The embossing apparatus (200) as set forth in claim 28, wherein the optically transparent silicone-based elastomer material (44) is a material selected from the group consisting of polydimethylsiloxane, SYLGARD182, SYLGARD 183, SYLGARD 184, and SYLGARD 186.

30. The embossing apparatus (200) as set forth in claim 28, wherein the optically transparent transfer adhesive layer (51) is an arcclear DEV-8932 optically transparent silicone adhesive.

31. The embossing apparatus (200) as set forth in claim 17, wherein the optically transparent cylinder (69) is made of a material selected from the group consisting of glass, plastic, and quartz.

32. The embossing apparatus (200) as set forth in claim 17, wherein the ultraviolet light source (99) further includes a reflector (99r) for focusing the ultraviolet light (L) at a location where the imprint stamp (20t) is urged into contact with the coated side (101c) so that the photopolymer material (301) is not cured before the imprint pattern (20q) is embossed in the photopolymer material (301).