Die lip for strip coating

Information

  • Patent Grant
  • 6803076
  • Patent Number
    6,803,076
  • Date Filed
    Wednesday, October 23, 2002
    21 years ago
  • Date Issued
    Tuesday, October 12, 2004
    19 years ago
Abstract
The invention is a contact die for dispensing of flowable material on a substrate. The contact die includes at least one die block including a first internal passage. A die lip portion is disposed on the die block having a lateral dimension. A first plurality of orifices is disposed through the die lip portion proximate to each other and in communication with the internal passage to dispense flowable material as a single strip on the substrate. A first edge is disposed on one lateral side of the first plurality of orifices to direct the flowable material.
Description




TECHNICAL FIELD




The present invention relates to coating dies. More particularly, the present invention relates to coating strips of flowable material on a substrate.




BACKGROUND OF THE INVENTION




A variety of techniques are known for forming multiple strips of a composition onto a substrate. In those processes, a composition is applied to a web in the form a plurality of strips, each of which is separated from an adjacent strip by a region which is uncovered. One example of an extrusion type apparatus used in this type of process is described in U.S. Pat. No. 4,106,437, incorporated by reference herein. Extrusion type dies are disadvantaged in that as the composition is extruded onto the substrate, the composition can “neck down” or decrease in width and thickness between the exit of the die and the substrate. In certain applications, this method cannot generate sufficiently precise strip widths and thicknesses.




An alternate process for applying strips to substrate is contact coating type dies. In contact coating, the die is disposed close to the substrate so that “necking down” of the composition is eliminated. Thickness of the composition is adjusted by pulling the composition through a clearance between the substrate and an obstruction. When the end process involves dispensing relatively viscous material (e.g., greater than 1000 centipoise) the coating die can be subjected to high pressures which act to deform the structure of the die. A common required characteristic of the strips is a uniform cross-sectional profile. Deflection of the die can result in a non-uniform cross-sectional profile of the flowable material being coated onto the substrate. An additional requirement in certain applications is to maintain the edges of the strip of flowable material to a high level of precision (e.g., perpendicular to the substrate). Additionally, in some contact dies, as the substrate moves relative to the die, it is common for the substrate to wear on a portion of the die so that this portion would eventually require replacement. The rubbing of the substrate on the die can also cause a “necking down” of the web, potentially causing variation in strip width. This “necking down” can also affect the variety of substrates which can be used with the die.




Achieving a precise profile of the strip of flowable material along with precise edge definition as well as decreasing the amount of wear on the die are desirable improvements in strip coating technology. In particular, the uncoated portion of the substrate typically is the portion of the substrate which wears on the die. Thus, as the uncoated portion of the substrate increased, the wear of the substrate on the die increased, having the effect of limiting the percentage of uncoated substrate which can be manufactured due to the high wear of the die.




BRIEF SUMMARY OF THE INVENTION




The invention is a contact die for dispensing of flowable material on a substrate. The contact die includes at least one die block including a first internal passage. A die lip portion is disposed on the die block having a lateral dimension. A first plurality of orifices is disposed through the die lip portion proximate to each other and in communication with the internal passage to dispense flowable material as a single strip on the substrate. A first edge is disposed on one lateral side of the first plurality of orifices to direct-the flowable material.




The die is used to dispose flowable material onto the substrate by translating the flowable material through the first internal passage in the die block. The flowable material is translated through the first array of orifices through the die lip and in communication with the first internal passage. The die lip has a lateral dimension. The flowable material is directed with the first edge. The first edge is proximate one lateral side of the first array of orifices. One edge of the first strip of flowable material on the substrate is defined with the first edge.











BRIEF DESCRIPTION OF THE DRAWINGS




In this disclosure, different embodiments of the invention are illustrated. Throughout the drawings, like-reference numerals are used to indicate common features or components of the device.





FIG. 1

is a schematic view of one embodiment of the inventive die.





FIG. 2

is an isometric view of one embodiment of the die.





FIG. 2A

is an isometric view of the area indicated by reference nos.


2


A,


2


B in

FIG. 2

with the rod partially withdrawn.





FIG. 2B

is an isometric view of the area indicated by reference nos.


2


A,


2


B in

FIG. 2

with the rod completely withdrawn.





FIG. 2C

is a cross-sectional view of one embodiment of strip coated substrate.





FIG. 3A

is an isometric view of one embodiment of the inventive die lip.





FIG. 3B

is an isometric view of an alternate embodiment of the inventive die lip.





FIG. 4

is a schematic view of the inventive die lip portion, rod and coated substrate.





FIG. 5

is an elevational end view of one embodiment of the inventive die lip portion as taken along lines


5





5


of FIG.


3


.





FIG. 6

is a view of the inventive die lip portion as taken along lines


6





6


of

FIG. 3A

, with edge dams included.





FIG. 7

is a cross-sectional view of an alternate embodiment of the inventive die lip portion.





FIG. 8

is a perspective view of one embodiment of a single-edge dam for the inventive die.





FIG. 8A

is a perspective view of an alternate embodiment of a single-edge dam for the inventive die.





FIG. 9

is an elevational view of the single-edge dam illustrated in FIG.


8


.





FIG. 10

is a perspective view of a double-edge dam of the inventive die.





FIG. 11

is an elevational view of the full die shown in FIG.


10


.





FIG. 12

is schematic view of an alternate embodiment of the inventive die.











While the above-identified drawing figures set forth different embodiments of the apparatus used in the invention, other embodiment were also contemplated, as noted in the discussion. In all cases, this disclosure presents the invention by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art which fall within the scope and spirit of the principle of the invention.




DETAILED DESCRIPTION




A schematic partial view of the inventive contact die is shown at


10


in FIG.


1


. Die


10


is illustrated in relation with roll


12


and substrate


14


(shown in dotted lines). In the embodiment illustrated, substrate


14


is typically a polymer web translating in the direction of arrow


16


. It should be noted, however, that the invention can be used with almost any type of substrate or surface (e.g., paper, foil, cloth, glass, wood and metal, among others). Additionally, instead of the substrate translating past the die, the die may be translated over the substrate, depending upon the end application.




According to the present invention, the contact coating method generally involves a supported substrate. The supported substrate provides the normal force to the coating fluid necessary to thin it to the desired thickness. Non-limiting examples of a supported substrate include a roll or a belt. The skilled in the art are capable of selecting the appropriate support for a selected substrate and coating fluid to enable the contact coating of the substrate.




Die


10


includes a first die block


18


, second die block


20


, block manifold


22


, internal passage


24


, die lip


26


, lip manifold


28


, orifice


30


, orifice chamber


31


, tertiary manifold


32


and rod


34


.




In contact coating, flowable material


36


(e.g., a liquid) reaches the desired thickness on substrate


14


by pulling the flowable material through a clearance between the substrate and an obstruction, which in this embodiment is rod


34


, but which could be other structures including a die lip, knife, roller or blade, among others. The moving substrate provides the motive force to force the flowable material between the substrate and obstruction, whereas the obstruction serves to redirect excess liquid. The flow of the flowable material is characterized by a changing velocity across the clearance between the substrate and the obstruction. While the term “coating” is used to describe the flowable material on the substrate, “film” can also be used.




Flowable material (indicated by arrows


36


) is forced into block manifold


22


, or other means of distributing the flowable matter (such as a gear manifold or positive displacement pumps, among others) typically with an extruder or pump (not shown) as is known in the art. While contact die


10


is illustrated as having two main portions (first and second die block


18


and


20


, respectively), it should be understood that almost any variation in contact die configuration (e.g., single block) is contemplated. Flowable material


36


is forced through internal passage


24


formed between first and second die blocks,


18


and


20


, where it enters die lip


26


. Flowable material


36


then enters lip manifold


28


, which is in communication with internal passage


24


. Lip manifold


28


provides an internal opening in die lip


26


which allows the flowable material inside the lip manifold


28


to equalize in pressure along the lateral dimension of die lip


26


(i.e., into the page of FIG.


1


). Flowable material


36


then is forced through orifice chamber


31


and out of orifice


30


into tertiary manifold


32


. Tertiary manifold


32


is disposed between output edge


38


of die lip


26


and rod


34


. Tertiary manifold


32


is an area between die lip


26


and rod


34


downstream from orifice


30


. Tertiary manifold


32


again allows flowable material


36


to equalize in pressure along the lateral dimension of die lip


26


(i.e., into the page of FIG.


1


). Flowable material


36


is preferably dispensed from multiple orifices (discussed further with respect to FIGS.


2


A and


2


B). Flowable material


36


is directed onto substrate


14


. Flowable material


36


and substrate


14


then pass between roll


12


and rod


34


. As mentioned previously, this brings flowable material


36


to the proper thickness as well as smoothing flowable material


36


as is desirable in certain applications. As illustrated, substrate


14


preferably does not directly contact die lip


26


, thereby preventing wear of die


10


and/or “necking down” of the substrate


14


due to minimizing friction caused by the translating substrate


14


over the die lip


26


.




Inventive contact die


10


can utilize flowable material


36


comprising any material dispensable through a coating die. Examples of materials which can be coated onto the substrate include (but are not limited to): adhesives, melts, solutions and dispersions, among others.





FIG. 2

illustrates a perspective view of one embodiment of the inventive contact die


10


. In this view, lateral dimension


40


of die lip


26


is more clearly shown, as well as outer curved surface


35


of rod


34


. Die lip


26


includes a plurality of bolt holes


42


used to secure die lip


26


to first die block


18


. While three bolt holes


42


are illustrated, these are shown for exemplary purposes only. Any number of bolt holes


42


may be used to secure the die lip


26


, or alternatively the die lip


26


can be integrally formed with the contact die


10


(e.g., with first die block


18


). Thus, various die lip


26


embodiments can be removable or non-removable, depending upon the desired application.




Additionally, edge dams


44


A-


44


G are illustrated as being attached to die lip


26


. Edge dams


44


are used to define the coated and uncoated portion of substrate


14


(shown by dotted lines), which is discussed in further detail below. Edge dams


44


can be double-edge dams as shown by edge dams


44


B-


44


G or half dams as shown by edge dam


44


A. It should be noted that throughout the description, when specific elements are referred to out of a general element type, they will be referred to using an appended letter with the reference number (e.g., “edge dam


44


A”). When the general element type is referred to, indicating characteristics similar to all the element types, no letter will be appended (e.g., “edge dam


44


”).





FIGS. 2A and 2B

illustrate a partial view of the die of FIG.


2


. In

FIG. 2A

, rod


34


is partially retracted and in

FIG. 2B

, rod


34


has been removed, offering a view of a first plurality (or array) of orifices


46


. The location of first plurality of orifices


46


corresponds to orifice


30


described and shown with respect to the schematic view of FIG.


1


. Edge dam


44


A, which is illustrated as a half edge dam, and edge dam


44


B are also shown. Edge dams


44


A and


44


B each have a directing edge


48


A and


48


B, respectively, disposed on both lateral side of the plurality of orifices


46


(along lateral dimension


40


of die lip


26


). Directing edge


48


A guides the flow in a first lateral direction and directing edge


48


B guides the flow in a second, opposite lateral direction. See, for example,

FIG. 6

, where directing edges


48


A and


48


B are illustrated.




Directing edges


48


A and


48


B direct flowable material dispensed through first plurality of orifices


46


before it passes onto substrate


14


and between rod


34


and roll


12


(see FIGS.


1


and


2


). Directing edges


48


A and


48


B thereby precisely form edges on strips of flowable material


36


dispensed onto substrate


14


. Varying the angle at which directing edges


48


are disposed allows the shape of the edge of the flowable material to be changed according to the end application.




Additionally, edge dams


44


also include rod faces


50


as illustrated by rod faces


50


A and


50


B for edge dams


44


A and


44


B, respectively. It is preferable that all rod faces


50


are disposed proximate to and have a shape conforming to outer curved surface


35


of rod


34


. Most preferably, rod


34


and rod faces


50


are in such close proximity that flowable material is prevented from extending between rod face


50


and rod


34


while gas is allowed to escape therebetween. Preventing the spread of flowable material in this manner assures that the strip of flowable material is accurately positioned on the substrate.




One method for assuring tight tolerance in a die utilizing a rotating rod design (known in the art) is to machine the rod faces


50


so as to slightly engage rod


34


. By forming either rod


34


or edge dams


44


out of material that have differing hardnesses (i.e., edge dams


44


harder than rod


34


, or rod


34


harder than edge dams


44


) a slight wearing of either rod faces


50


or outer curved surface


35


of rod


34


will occur as rod rotates during operation of the die, assuring minimal clearance between the two elements. Additionally, it is preferable that edge dams


44


are formed of a material harder than the substrate, so that any contact between substrate and edge dams


44


does not prematurely wear edge dams


44


. It should be understood that edge dams can be manufactured such that various portions of edge dams are constructed of different materials (e.g., directing edges


48


formed of a different material than the remainder of edge dams


44


).




The clearance between the rod


34


and rod face


50


can vary according to the viscosity of the flowable material being dispensed, and the pressure at which the die is operating. For example, a more viscous material dispensed at lower pressure will allow for more clearance than a less viscous material dispensed at a higher pressure. The viscosity and pressure will vary according to the end application for which the contact die is used.




The use of multiple orifices disposed immediately proximate each other and between directing edges allows high pressures and viscosities to be used with inventive die


10


without causing bowing or distortion of die lip


26


, as previously could occur using lateral slots. Multiple orifices increase the structural integrity of die lip


26


. By preventing distortion of the portion of the die lip where flowable material is dispensed, the cross-sectional profile of the flowable material coated on the substrate is precisely maintained (i.e., minimal variation in thickness).





FIG. 2C

illustrates a partial cross-sectional view of one embodiment of substrate


14


having strips


51


of flowable material


36


coated thereto by the inventive die. As mentioned and shown previously, directing edges


48


or die


10


form precisely shaped edges


53


of each strip


51


. Edges


53


are preferably substantially perpendicular to substrate


14


(although other angles are contemplated). The precise formation of edges


53


is required in certain applications. Most preferably, the cross-sectional profile of the flowable material on the substrate is uniform and is within plus or minus 5 percent variance along the cross-sectional profile. Most preferably, the cross-sectional profile is within plus or minus 1 percent variance.





FIG. 3A

illustrates an embodiment of die lip


26


with the edge dams removed. Along with first plurality of orifices


46


, second, third, fourth, fifth and sixth plurality (or arrays) of orifices (


52


,


54


,


56


,


58


and


60


, respectively) are illustrated. Flowable material


36


dispensed by each plurality of orifices


46


,


52


,


54


,


56


,


58


and


60


merges to form each strip of flowable material


36


dispensed on the substrate. While six arrays are illustrated, any number of arrays can be used without departing from the scope of the invention. Additionally, while fifteen individual, similarly shaped and sized orifices


30


make up each respective array


46


,


52


,


54


,


56


,


58


and


60


, any number or shape orifice


30


can be used as described in PCT Publication No. WO99/55790, incorporated by reference in its entirety herein. In the most preferred embodiment, orifices have a diameter of between 0.06 inch (1.5 mm) to 0.02 inch (0.5 mm). Similarly, the number, size and shape can vary from array-to-array and within each array. Additionally, while each array is illustrated as having individual orifices


30


aligned along the lateral dimension


40


of the die lip


26


, any orientation can be used without departing from the scope of the invention. Those skilled in the art are capable of selecting orifice patterns and orifice shapes based on desired characteristics to achieve a strip thickness and width.




As previously described, flowable material


36


is forced into lip manifold


28


. In the embodiment illustrated, lip manifold


28


extends the full lateral dimension


40


of die lip


26


. Thus, one internal passage


24


in the die block can be used to feed flowable material


36


to the lip manifold


28


and through each array of orifices (


46


,


52


,


54


,


56


,


58


and


60


).




In an alternate embodiment shown in

FIG. 3B

, each array can be separated from an adjacent array using dividers


62


. In this manner, different internal passages in the contact die


10


can be in communication with different arrays, allowing different flowable materials


36


A-


36


F to be dispensed on the substrate. Note that any mix of various flowable materials could be used. For example, instead of six different materials, two internal passages can be utilized to dispense two different materials, alternating between arrays. Alternatively, six internal passages could be in individual communication with each array, but the same flowable material forced through each array of orifices.




As illustrated in

FIG. 4

, once substrate


14


passes die lip


26


and rod


34


, edge dams


44


act to direct flowable material


36


into strips (or covered areas)


51


on substrate


14


. The lateral length of the rod face


50


portion of edge dam


44


between the distributed flowable material


36


prevents flowable material


36


from coating substrate


14


. Thus, various covered areas


51


and uncovered areas


66


can be defined on substrate


14


. While six covered areas


51


are illustrated all having approximately the same width (i.e., any lateral dimension


40


), die lip


26


can be configured to coat coated areas


51


at any width and at any number. Preferably, the sum of coated areas


51


comprises less than 65 percent and most preferably 35 percent or less of the total area of substrate


14


passing under die lip


26


. Using removable die lips


26


(discussed previously) allows for efficiently changing the width and/or number of coated areas by changing from one die lip to a second die lip having a different array and edge configuration.





FIG. 5

illustrates an elevational view of one embodiment of die lip


26


as taken along line


5





5


of FIG.


3


A. In one preferred embodiment of die lip


26


, O-ring


67


is disposed in groove


69


, formed into die lip


26


. O-ring


67


and groove


69


extend laterally along the lateral dimension of die lip


26


(i.e., into the page for FIG.


5


). O-ring


67


provides a seal between die lip


26


and second die block


20


(shown in dotted lines), preventing flowable material


36


from extending between the mating faces of die lip


26


and second die block


20


.




It should also be noted that in one embodiment, lip manifold


28


extends into die lip


26


such that lip manifold


28


is formed completely within die lip


26


(a single piece of material). This minimizes the distortion of the die lip


26


. Minimizing distortion of the die lip


26


helps to assure a continuous cross-section of flowable material


36


is coated on the substrate.




The embodiment illustrated in

FIG. 6

is taken in the direction of line


6





6


of

FIG. 3A

, and includes edge dams


44


. As can be seen in

FIG. 6

, the relationship between each array of orifices


46


,


52


,


54


,


56


,


58


and


60


and edge dams


44


is such that each array and adjoining edge dams


44


form six coating (or working) sections, section


68


A, section


68


B, section


68


C, section


68


D, section


68


E and section


68


F. These coating sections


68


define the width of each strip of flowable material


36


coated on substrate


14


(and therefore the width of each uncovered area


66


, discussed with respect to FIG.


4


). The width of each section


68


can be varied individually as appropriate for the end application.




Section


68


A includes first array


46


and first and second directing edge


48


A and


48


B, as described previously with respect to

FIGS. 2A and 2B

. Similarly, section


68


B includes second array


52


and third and fourth directing edges


48


C and


48


D. Section


68


C includes third array


54


and fifth and sixth directing edges


48


E and


48


F. Section


68


D includes fourth array


56


and seventh and eighth directing edges


48


G and


48


H. Section


68


E includes fifth array


58


and ninth and tenth directing edges


48


I and


48


J. Section


68


F includes sixth array


60


and eleventh and twelfth directing edges


48


K and


48


L.




In one embodiment of the inventive die lip


26


, orifices may extend across most of the lateral length of the die lip


26


, as indicated by orifices


30


shown in dotted lines. Edge dams


44


B-


44


G can be placed as indicated to block certain orifices which directs the flowable material through the unblocked orifices. Additionally, orifices may be partially blocked, depending upon the end application, and desired strip widths.





FIG. 7

is an alternate embodiment of die lip


26


seen in a cross-section. The configuration of these passages (i.e., lip manifold


28


′ and orifice chamber


31


′) can vary according to the configuration of internal passage


24


in first die block


18


(discussed and illustrated in FIG.


1


), coating material (i.e., flowable material


36


) among other reasons. It should also be understood that while a 60 degree die lip


26


is illustrated, other die lip configurations (e.g., 40 degree) can be utilized without departing from the spirit and scope of the invention.





FIGS. 8

,


9


,


10


and


11


illustrate one embodiment of edge dams


44


. As mentioned previously, edge dam


44


A (shown in

FIGS. 8 and 9

) is a single-edge dam, meaning only one directing edge


48


A is disposed on edge dam


44


A. Thus, the single-edge dam is preferably disposed next to only one array of orifices and not between two arrays (since only one directing edge is provided). Edge dam


44


B, on the other hand, is a double-edge dam, having two directing edges


48


B and


48


C, allowing it to be placed between two arrays of orifices.




While each edge dam


44


is illustrated as a separate element which is bolted to die lip


26


through bolt hole


71


(see FIG.


6


), other ways of forming directing edges


48


are also contemplated by the current invention. For example, one or all of the edge dams


44


can be integrally formed with die lip


26


. Directing edge


48


A can be formed on wing


73


extending from edge dam


44


. Wing


73


may be used to block some of orifices


30


(as described with respect to FIG.


6


). Alternatively, a person skilled in the art would understand that edge dams


44


can be constructed without wing


73


, as illustrated in FIG.


8


A. As is best illustrated by

FIGS. 9 and 11

, rod face


50


A has a curvature, which is designed to substantially conform to outer surface


35


of annular rod


34


(shown in FIGS.


2


and


2


A). While edge dams


44


may be formed of various materials, preferably they are formed of bronze so as to provide soft wear material against a harder rod material (such as case hardened steel). As previously discussed, other materials for edge dams


44


, and particularly for directing edges


48


and rod faces


50


, are contemplated by the invention, and can be chosen such that outer surface


35


of rod


34


is harder than edge dams


44


, or vice versa.




As mentioned, other methods of forming directing edges


48


into contact die


10


are contemplated by the invention.

FIG. 12

is a schematic view illustrating an alternate embodiment of contact die


10


. Rod


34


and roll


12


are illustrated in relation to die


10


, with rod


34


slightly retracted to afford a view of a seventh plurality (or array) of orifices


72


. In this instance, die lip


26


is formed integrally with die


10


. Additionally, directing edge


48


K is formed directly into die lip


26


.




The configuration described provides a coating die which decreases the contact between the substrate and the die over previous methods while providing the capability of coating multiple strips, each strip having cross-sectional edges maintained and a high degree of cross-sectional thickness uniformity, onto a substrate.




Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.



Claims
  • 1. A contact die for dispensing a flowable material on a substrate comprising:at least one die block including a first internal passage; a die lip portion removable from and replaceable on the die block, the die lip portion having a lateral dimension, a first plurality of orifices disposed through the die lip portion proximate to each other and in communication with the internal passage so as to dispense flowable material as a single strip on the substrate; a first edge disposed on one lateral side of the first plurality of orifices so as to direct the flowable material; and a rod disposed substantially parallel to the lateral dimension of the lip.
  • 2. The die of claim 1 and further comprising:a second edge disposed on an opposite lateral side of the plurality of orifices so as to direct the flowable material.
  • 3. The die of claim 2 wherein the first edge and the second edge are substantially parallel.
  • 4. The die of claim 2 wherein the first edge and the second edge are substantially non-parallel.
  • 5. The die of claim 1 wherein the plurality of orifices are disposed through a first section of the die lip portion and further comprising:a second section of the die lip including a second plurality of orifices disposed therethrough; a third edge disposed on one lateral side of the second plurality of orifices so as to direct the flowable material; and a fourth edge disposed on the other lateral side of the second plurality of orifices so as to direct the flowable material.
  • 6. The die of claim 5 wherein the second plurality of orifices are in communication with the first internal passage, so as to dispense a second strip on the substrate.
  • 7. The die of claim 5 and further comprising:a second internal passage disposed through the die block, wherein the second plurality of orifices are in communication with the second internal passage, so as to dispense a second strip on the substrate.
  • 8. The die of claim 1 wherein the die lip has at least three sections having orifices such that less than 65 percent of the lateral dimension of a working portion of the die lip is defined by these sections.
  • 9. The die of claim 1 wherein the distance between the rod and the first edge prevents the flowable material from flowing between the first edge and the rod.
  • 10. The die of claim 9 wherein the first edge is formed of bronze.
  • 11. The die of claim 9 wherein the rod is harder that the first edge.
  • 12. The die of claim 9 wherein the first edge is harder than the rod.
  • 13. The die of claim 1 wherein the first edge is harder than the substrate.
  • 14. The die of claim 1 wherein each of the orifices has a generally cylindrical shape.
  • 15. A method for dispending flowable material onto a supported substrate comprising:translating a flowable material through a first internal passage in a die block; translating the flowable material through a first array of orifices disposed through a die lip, the die lip removably connected to the die block and in communication with the first internal passage, the die lip having a lateral dimension; directing the flowable material with a first edge disposed proximate one lateral side of the first array of orifices; and defining one edge of a first strip of flowable material on the supported substrate with the first edge.
  • 16. The method of claim 15 and further comprising;directing the flowable material with a second edge disposed proximate an opposite lateral side of the array to define a second edge of the first strip of flowable material on the substrate.
  • 17. The method of claim 15 and further comprising:translating the flowable material through a second array of orifices disposed through the die lip and in communication with the first internal passage; and directing the flowable material with a third edge disposed proximate one lateral side of the second array of orifices to define one edge of a second strip of flowable material on the substrate.
  • 18. The method of claim 15 and further comprising:translating a flowable material through a second array of orifices disposed through the die lip and in communication with a second internal passage; and directing the flowable material using a third edge disposed proximate one lateral side of the second array of orifices to define one edge of a second strip of flowable material on the substrate.
  • 19. The method of claim 18 and further comprising:directing the flowable material using a fourth edge disposed proximate the other lateral side of the second array of orifices to define a second edge of the second strip of flowable material on the substrate.
  • 20. The method of claim 15 and further comprising:covering less than about 65 percent of the substrate with the flowable material.
  • 21. The method of claim 15 and further comprising:maintaining a substantially constant cross-sectional profile of the first strip.
  • 22. The method of claim 21 and further comprising:maintaining a variation in thickness of the first strip of no more than plus or minus 5 percent.
  • 23. The method of claim 15 further comprising:forming a cross-sectional profile of the first strip having edges disposed substantially perpendicular to the substrate.
  • 24. A die dispensing a flowable material on a substrate comprising:at least one die block including a first internal passage; a die lip portion removably connected to the die block having a first plurality of orifices disposed through the die lip portion proximate to each other and in communication with the internal passage; a rod disposed substantially parallel to the lateral dimension of the lip; a first edge disposed on one lateral side of the first plurality of orifices; and a second edge disposed on the other lateral side of the plurality of orifices.
  • 25. A method for disposing flowable material onto a supported substrate comprising:directing a flowable material through a first internal passage in a die block; directing the flowable material through a first array of orifices disposed through a die lip removable from the die block, the first array of orifices in communication with the first internal passage; directing the flowable material with a first edge disposed proximate one end of the first array of orifices to define a first lateral edge of a first strip of flowable material on the supported substrate; directing the flowable material with a second edge disposed proximate the other end of the array to define a second lateral edge of the first strip of flowable material on the supported substrate; directing the flowable material through a second array of orifices disposed through the die lip and in communication with the first internal passage; directing the flowable material with a third edge disposed proximate one end of the second array of orifices to define one lateral edge of a second strip of flowable material on the supported substrate; directing the flowable material using a fourth edge disposed proximate the other end of the second array of orifices to define a second lateral edge of the second strip of flowable material on the substrate; covering less than about 65 percent of the substrate with the first strip and the second strip; and maintaining a substantially constant cross-sectional profile of the first strip and the second strip.
  • 26. A contact die for dispensing a flowable material on a substrate comprising:at least one die block including a first internal passage; a die lip portion of the die block having a lateral dimension, a first a first plurality of orifices disposed through the die lip portion proximate to each other and in communication with the internal passage so as to dispense flowable material as a single strip on the substrate; a rod disposed substantially parallel to the lateral dimension of the lip; a first means for guiding the lateral flow of the flowable material in a first direction; and a second means for guiding the lateral flow of the flowable material in a second, opposite direction.
CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. 119(e) from U.S. provisional application No. 60/372,922, titled “Rod Die Lip for Strip Coating”, filed Apr. 16, 2002 by Pentti K. Loukusa, Kurt W. Oster, Todd L. Peterson, Robert B. Secor, Robert W. Shipman, and Merl J. Steffen.

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Foreign Referenced Citations (1)
Number Date Country
WO 9955790 Nov 1999 WO
Provisional Applications (1)
Number Date Country
60/372922 Apr 2002 US