Synthetic torn patterned roller and its method of production

A patterned synthetic sponge mimics a natural sea sponge when creating faux paint finishes. Such synthetic sponge is formed from an open cell elastomeric material that bears a pattern that has been created by a rotating grinding wheel that removes sponge material with a tearing action. A rotating silicon carbide, or other abrasive grit, grinding wheel preferably is used to remove the elastomeric sponge material, which preferably is made from an open cell, inter alia, polyurethane, polyether, polyester foamed elastomer. A paint roller made from the novel patterned synthetic sponge has its edges beveled.

CROSS-REFERENCE TO RELATED APPLICATIONS
 None.
 STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
 Not applicable.
 BACKGROUND OF THE INVENTION
 The present invention generally relates to tools used in the creation of
 faux paint finishes and more particularly to a patterned synthetic sponge
 that mimics natural sea sponge in the creation of faux paint finishes.
 Broken pattern surface-coatings were popular in the 1930's. They were
 produced by techniques known as "ragging on" and "sponging" and which
 involved a rag or sponge that was used to disturb a freshly painted wall
 to produce a broken pattern. Considerable skill was required to produce an
 aesthetically pleasing affect.
 Today, such specialty finishes can involve more than one color of paint in
 order to create a look that otherwise is only available from expensive
 wall coverings. One such technique involves the application of a base coat
 of one paint and the selective application of a different color top coat
 that can be applied by rag or sponge rolling. Alternatively, a top coat
 can be applied over a dried base coat and some of the top coat removed
 with a rag, sponge, cheese cloth, or other tool to create the specialty
 finish desired. U.S. Pat. Nos. 4,930,179 and 5,206,979 are examples
 thereof. In fact, it even has been proposed to use a bifurcated roller to
 apply two different colors at the same time in U.S. Pat. No. 5,713,095. A
 rag wrapped around a tube is another tool proposed in U.S. Pat. No.
 5,471,703.
 In reality, many of these tools were designed to take the place of scarce
 and expensive natural sea sponges that provide the most pleasing specialty
 faux finishes. Despite these designs, however, there still is a need to
 create a synthetic sponge that would mimic a natural sea sponge in its
 ability to create faux paint finishes.
 BRIEF SUMMARY OF THE INVENTION
 A patterned synthetic sponge mimics a natural sea sponge when creating faux
 paint finishes. Such synthetic sponge is formed from an open cell
 elastomeric material that bears a pattern that has been created by a
 rotating grinding wheel that removes sponge material with a
 tearing/teasing action. A rotating silicon carbide, or other abrasive
 grit, grinding wheel preferably is used to remove the elastomeric sponge
 material, which preferably is made from an open cell, inter alia,
 polyurethane, polyether, polyester foamed elastomer. A paint roller made
 from the novel patterned synthetic sponge has its edges beveled.
 An array of, for example, servo controlled Carborundum.RTM. silicon carbide
 grinding wheels can be used to create patterns in the synthetic sponge
 which patterns are stored in a computer that also controls the
 manufacturing process. When the patterned synthetic sponges are in roller
 form, they can be used to create unique faux paint finishes that
 heretofore could only be created using natural sea sponges.
 Advantages of the present invention include the ability to create roller
 that mimic natural sea sponges in their ability to create faux paint
 finishes. Another advantage is that the inventive patterned sponges can be
 mass-produced economically. These and other advantages will be readily
 apparent to those skilled in the art based on the present disclosure.

The drawings will be described in detail below.
 DETAILED DESCRIPTION OF THE INVENTION
 The key to mimicking natural sea sponges is not to orderly remove the
 material by a cutting action that would create smooth edges; but rather,
 to remove material by a tearing action to create ragged edges. Such ragged
 edges created by a tearing action yield a natural sponge-like affect when
 used in creating faux or rag paint finishes. In order to obtain such a
 tearing action, the manufacturer should avoid using sharp edged rotating
 cutting elements such as router bits. Rather, the manufacturer should use
 a simple grinding wheel that grabs the synthetic sponge material and
 thereby tears it. That is not to say that some "cutting" of the material
 does not happen, as it does. However, many of the edges are torn away by
 the grinding wheel.
 When the synthetic sponge material is composed of an open cell elastomeric
 material, the torn edges of the open cells are quite similar in structure
 to natural sea sponges. Thus, the desired affect can be achieved in
 decorating finishes, such as faux paint finishes, using the novel
 patterned synthetic sponge. In this regard, the shape or type of pattern
 is not critical since it is the creation of torn edges that is desired.
 For present purposes, then, the pattern can be random or predefined, as
 the creation of torn edges of the open cell foam elastomer is the effect
 desired.
 Three additional problems prevalent with prior art patterned rollers are
 paint loadup in the patterns, slippage of the roller, and tracking. The
 first problem is attributed to conventional rollers only having about a
 0.25 inch deep pattern and often this is molded into a closed cell foam
 elastomer. This problem is intentionally solved by using patterns that
 typically range in depth from about 0.5 to 0.75 or more inches in depth.
 Such extra deep patterns avoid the pattern grooves from becoming full of
 paint or loading up which phenomenon results in an ineffective pattern at
 best being transferred to the wall surface.
 The second addressed problem is familiar to all those who paint with
 rollers and inadvertently roll too much paint on the wall. Instead of the
 paint roller rolling, it slips on the too heavily paint laden wall.
 Intentionally, this problem is solved by using an "open cell" foam that
 essentially "grips" the painted wall surface by dint of the myriad of open
 cells that act like tiny suction cups. The novel rollers disclosed herein
 "grip" the painted wall surface much like a radial tire grips the road
 surface (compared to a biased tire).
 The third addressed problem involves the edges of the paint roller leaving
 a "track" or ridge of paint that must be smoothed over with each adjacent
 are being painted. When transferring a pattern to a painted wall, the
 painter cannot overlap each adjacent rolled area at the risk of destroying
 part of the pattern already laid down. To intentionally solve this
 problem, the inventive rollers have their edges beveled. Such edge
 beveling permits the applicator to place each adjacent pattern directly in
 abutting juxtaposition with each adjacent pattern without overlapping the
 prior pattern.
 It will be observed, then, that the uniqueness of the inventive
 torn-patterned sponge rollers have properties that can be translated to
 other foam rollers that are not sponge-like in nature. For such
 conventional paint rollers made from typically less elastomeric foams, the
 pattern will be cut with smooth edges with, for example, a router type
 bit; however, such patterns will be deeper (0.5"-0.75"), will be made from
 an open cell foam, and will have their edges beveled. In this regard, such
 features also can be used to advantage with stippling rollers that
 transfer patterns to topping or stippling compound (see, for example, U.S.
 Pat. Nos. 5,378,419, 5,414,434, and 5,580,608 for more information on
 topping or stippling compounds and patterns formed therein).
 Referring now to FIG. 1, conventionally configured elongated paint roller
 10 is seen in perspective view formed from annular elastomer 12 that
 surmounts inner annular tube 14. This is a conventional paint roller used
 by both professional and homeowners to paint interior walls. Heretofore,
 such paint rollers were made from closed cell elastomeric foamed
 materials. The invention teaches that an open cell foam elastomer can
 provide unexpected advantages by relying on the ability of the exposed
 open cells on the outer surface of roller 10 to better grip the wet paint
 on the wall and, thus, prevent the tendency of the roller to slip. Such
 slippage is even more detrimental when rolling a pattern into topping
 compound, a so-called stippling operation. Nevertheless, one preferred
 configuration of the novel torn patterned open cell synthetic sponge is in
 such elongate paint roller configuration. There are, however, a variety of
 other useful configurations for the novel torn patterned open cell
 synthetic sponge as those skilled in the art will appreciate based on the
 instant disclosure.
 Referring now to FIG. 2, depicted is novel torn patterned open cell
 synthetic sponge roller head 16 which is formed from outer annular torn
 patterned open cell sponge elastomer 18 which surmounts and is bonded to
 inner annular core 20. Core 20 is designed to have a conventional paint
 roller wire core inserted thereinto, such core being rotatably affixed to
 a handle. Novel torn patterned open cell synthetic sponge roller 16 when
 affixed to such roller and handle then can be rolled into a thin layer of
 paint in a shallow pan and then brought into contact with the wall to be
 painted. The rolling action of the roller then transfers the paint from
 novel torn patterned open cell synthetic sponge roller 16 onto the wall in
 conventional fashion. The same operation would be practiced when
 transferring a pattern to topping compound, however the roller head would
 be dry and would transfer its pattern into the topping compound.
 Nevertheless, novel torn patterned open cell synthetic sponge roller head
 16 is characterized by the method by which the pattern was formed. That
 is, elastomeric material was removed from novel torn patterned open cell
 synthetic sponge roller head 16 by a tearing action rather than being cut.
 Thus, the manufactured should use a head to remove the elastomeric
 material that does not have sharp edges and will not effect a cutting
 action. Rather, it has been unexpectedly discovered that the elastomeric
 material should be removed by a tearing action to leave torn or ragged
 edges where the elastomeric material has been removed. In this regard, it
 should be understood that the pattern formed is unimportant in so far as
 the novel features of torn patterned open cell synthetic sponge roller
 head 16 are concerned. While any suitable pattern can be formed, so long
 as it is formed by a suitable tearing action in open cell synthetic sponge
 elastomeric material, the novel affects of torn patterned open cell
 synthetic sponge roller head 16 will be achieved. That is not to say that
 certain patterns may not be more aesthetically pleasing as this certainly
 is true; however, the present invention is not limited to any particular
 pattern.
 Torn patterned open cell synthetic sponge roller head 16 may even contain
 loosely-connected thin strands of elastomeric material as a result of the
 tearing action used in the manufacturing process. Indeed, the edges of the
 pattern will be quite ragged, uneven, and disheveled in appearance. Such
 appearance might even put off some users from believing that torn
 patterned open cell synthetic sponge roller head 16 could even be used to
 create unique and delicate paint patterns when creating faux painted
 walls. Such looks, however, are deceiving as will be amply demonstrated by
 simply using torn patterned open cell synthetic sponge roller head 16 only
 once.
 Creation of the torn pattern may even be accomplished by grasping the
 elastomeric material between the fingers and ripping out the grasping
 material. However, it does take a good deal of strength to tear such
 elastomeric material and such hand operation is not conducive to large
 scale manufacturing operations. Rather, the manufacturer must seek a
 method by which such hand tearing action can be achieved mechanically. An
 apparatus for implementing such action is depicted in simplified form in
 FIG. 3. In order to tear three-dimensional patterns into the open cell
 sponge material, apparatus 22 must accommodate x-axis, y-axis, and z-axis
 movement of its tearing head as its point of contact with the open cell
 sponge material. This is accomplished by use of drive unit 24 to move
 carriage assembly 26 down side rails 28, 30, in order to achieve y-axis
 movement as indicated by arrow 32. Conveniently, drive unit 24 can be an
 electrical motor having a pinion gear mounted to a shaft that engages the
 rack formed on the inside of rail 28 to form a rack and pinion drive.
 Alternatively, drive unit 24 could be hydraulically or pneumatically
 actuated, for example. For that matter, belts and pulleys, or other drive
 systems also could be used. The particular drive means used is a matter of
 choice by the manufacturer and is not a limitation of the present
 invention.
 Next, z-axis movement of grinding heads 34 and 36 is achieved by plunge
 drive units 38, 40, respectively,. Again, electric, pneumatic, hydraulic,
 or other motive means can be used to power plunge drive units 38, 40 that
 control the depth of the pattern being formed or z-axis control as
 indicated by arrow 42. Rotation of grinding heads 34, 36 is achieved by
 drive units 35, 37, respectively.
 X-axis control is uniquely achieved in apparatus 22 by rotating shafts 44,
 46 with drive units 48, 50, respectively. Again, drive units 48, 50 may be
 electric, pneumatic, hydraulic, or other motive means. Rotation of shafts
 44, 46, causes sponge blanks 52, 54, 56, and 60 to similarly rotate and
 achieve an effective x-axis movement as indicated by arrows 62 and 64. It
 will be appreciated that additional structural support will be provided to
 apparatus 22 in order to support rails 28, 30; shafts 44, 46; all drive
 units; etc. Such support structure is to be provided in conventional
 fashion.
 In order to impart a pattern into open cell sponge blanks 52, 54, 56, and
 58, all drive units need to be controlled and their operation coordinated.
 Thus, all drive units are connected to controller 66 as follows: drive
 unit 24 by line 68; drive unit 38 by line 70; drive unit 40 by line 72;
 drive unit 48 by line 74; and drive unit 50 by line 76. A conventional CNC
 can conveniently be used to advantage with desirable patterns stored in
 memory in controller 66. With today's computer controlled systems, the
 same pattern can be torn into sponge blanks 52, 54, 56, 58, or even
 different patterns can be torn into the sponge blanks. In this regard it
 should be understood that the number of shafts and roller blanks depicted
 in FIG. 3 are for illustrative purposes only and that a greater or lesser
 number of them could be provided in accordance with the precepts of the
 present invention.
 It should be understood also that a variety of machine designs other than
 that depicted in FIG. 3 could be envisioned for carrying out the present
 invention. The presently preferred design, however, is that depicted in
 FIG. 3.
 With respect to the actual creation of the torn pattern in sponge blanks
 52, 54, 56, 58, grinding heads 34 and 36 conveniently are made from
 conventional grinding wheels made from, for example, silicon carbide in a
 bonding matrix and typified by Carborundum.RTM. grinding wheels. The
 grittiness of such grinding wheels creates friction with the sponge
 material in the blank that results in a tearing of the sponge material for
 its removal. Referring to FIG. 4, blank 78 is shown in cross-section with
 grinding wheel 80 affixed to shaft 82 which in turn will be connected to a
 drive unit, such as, for example, drive unit 35 shown in FIG. 3. It will
 be observed that grinding wheel 80 has been uniquely shaped to have a
 cylindrical upper end and a nipple-shaped lower end that primarily engages
 sponge blank 78. An effective tearing action is achieved by such design.
 Referring to FIG. 5, if grinding wheel 34, for example, is plunged down to
 meet core 84 of blank 86 and blank 86 rotated 360.degree., two separate
 blanks 88, 90 will be created. Each blank 88, 90 then can be patterned and
 used, for example, by dipping each into a different color of paint to
 create truly unique faux patterns. Use of two abutting paint trays each
 filled with a different color of paint is but one technique for
 implementing such dual head faux painting regimen. Such method of
 manufacture is much simpler than the dual roller shown in U.S. Pat. No.
 5,713,095. In this regard, creation of such a dual-head roller as depicted
 in FIG. 5 (with the groove creating blanks 88, 90 as the pattern) is an
 advancement in the art for 2-color painting in general.
 Even with novel torn patterned open cell synthetic sponge roller head 16,
 the user is limited in the ability to effectively paint interior corners.
 Roller head 16 simply is too large to fit into an interior corner. In
 order to demonstrate the flexibility and adaptability of the present
 invention, reference is made to FIGS. 6 and 7 wherein corner open cell
 synthetic sponge roller 92 is depicted in side elevational view and in
 front elevational view, respectively. It will be observed that corner
 roller 92 is formed from handle 94 that is connected to the distal end of
 bent elongate wire 96. The proximal end of wire 96 bears roller core 98
 that is adapted to receive corner open cell synthetic sponge roller head
 100. Corner roller head 100 is made from open cell elastomeric sponge
 material that has been beveled at both ends to form a point about its
 central axis. The angle thus-formed desirably is about 90.degree. to mate
 with an interior corner. A torn pattern again has been formed in corner
 roller head 100 as has been described above. The extreme depth of the
 pattern clearly can be seen from FIG. 7. The user need only use roller
 head 16 on the flat wall surfaces and corner roller 92 in the corners to
 entirely faux paint a room with a pattern that effectively matches. The
 slight difference in the pattern between corner roller head 100 and roller
 head 16 will not be discernable to the ordinary observer.
 In this regard, the design of the inventive patterned corner roller can be
 carried over to a variety of other paint rollers even made from closed
 cell foams; although, the gripping effect of the invention open cell
 rollers is sacrificed. It will be appreciated that the depth of the
 pattern created in the inventive patterned rollers, then, can be used to
 advantage in the creation of rollers for applying a stipple pattern into
 topping compound. The inventive corner roller would have the same utility.
 The synthetic sponge may be formed from polyurethane, polyether, polyester,
 or like elastomer that is suitable for making a sponge product. Open cell
 foamed products can be made with suitable blowing agents and by other
 techniques commercially practiced in a variety of art fields. The degree
 of elasticity may vary from manufacturer to manufacturer. Indeed, a
 variety of elasticity's may function effectively for making the inventive
 torn patterned open cell synthetic sponge roller heads of the present
 invention. Of course, if use of the torn patterned open cell synthetic
 sponge roller head is for stippling topping compound, a stiffer foam would
 be desired than if faux painting was being done. Those skilled in the art
 will appreciate and be able to select the desired degree of elasticity
 desired of the torn patterned open cell synthetic sponge roller head
 depending upon the use being made thereof.
 It will be apparent to those skilled in the art that a variety of
 additional embodiments for the present invention can be envisioned based
 on the precepts of the present invention disclosed herein. In this
 application, all citations are expressly incorporated herein by reference.