Methods for manufacturing a paint roller and component parts thereof

Described is a method of making a laminated paint roller wherein a perforated strip of thermoplastic material is advanced, the perforated strip having holes there-through. A lubricant is applied to the inner surface of the advancing perforated strip of thermoplastic material. The lubricated, perforated strip of thermoplastic material is helically wound around a cooled mandrel so as to form a helically wound strip wherein the inner surface of the perforated strip faces the cooled mandrel and the outer surface of the perforated strip faces away from the cooled mandrel. The wound perforated strip is advanced along the cooled mandrel. A layer of adhesive is applied onto an outer surface of the wound perforated strip. A strip of composite cover material is helically wrapped about the wound strip and over the layer of adhesive, the outer surface of the composite cover material comprising a pile fabric, and the inner surface of the composite cover material comprising thermoplastic. A compressive force is applied upon the composite cover material to urge the composite cover material, the layer of adhesive and strip of thermoplastic material together against the cooled mandrel, thereby laminating the inner surface of the composite cover material to the outer surface of the strip. A method of making a composite cover material is also disclosed.

This application includes material which is subject to copyright protection. The Copyright owner has no objection to the facsimile reproduction by anyone of the patent disclosure, as it appears in the Patent and Trademark Office files or records, but otherwise reserves all copyright rights whatsoever.

FIELD OF THE INVENTION

This invention pertains to a method and apparatus for making paint rollers of the type used for applying paint to walls and the like. More specifically, the invention pertains to a method and apparatus for making paint rollers that are formed in a continuous process from a strip and a composite cover material.

BACKGROUND OF THE INVENTION

Paint rollers are widely used by professionals and amateurs for applying paint to walls, ceilings, and other surfaces. Typically the roller is used with an applicator having a handle terminating in a rotatable member to which the roller is secured. The roller itself generally comprises a paint absorbing and spreading cover affixed to a generally cylindrical core. The covers may be made from materials such as wool or polyester, and other cover materials that are well known in the art.

Years ago paint rollers were manufactured using a paper or chipboard core. Some manufacturers still make such paper core paint rollers. The manufacture of such cores is well known. Such cores, however, and the paint rollers made out of them, would often fall apart during use or during cleaning, especially during cleaning with paint solvents (such as, for example, turpentine or mineral spirits, such paint solvents are well known in the art). It has always been desirable, and still remains desirable, to make the paint roller resistant to paint solvents.

An advance in making paint rollers came when the paper cores were replaced with phenolic cores, that is, cores made from paper impregnated with phenolic. Such paint rollers withstood exposure to paint solvents much better than their paper or chipboard counterparts. The process of manufacturing phenolic cores is also well known. For example, according to one known technique, a reusable disposable roller is made by first feeding three phenolic impregnated paper strips at an angle to a mandrel for overlapping, helical winding to form an endless core. Typically, the phenolic strips are supplied in rolls that can be mounted on spindles for continuous feeding, and a continuous thermosetting glue is applied to the outer surfaces of the strips as they feed off the rollers such that the strips adhere together as they are helically wound to form the core. As the endless core is belt driven down the line, the core is heated in a multi-stage infrared heater, after which a hot melt glue is applied to the core's outer surface and a continuous strip of the cover material, such as polyester, is helically wound on to the core where it is secured by the hot melt. All that remains is to cut the resulting endless roller down to usable sizes, which is usually accomplished in two steps, first using a fly away cutter to cut, e.g., 65 inch stock, and then using another cutter to cut the stock into usable lengths of, e.g., seven or nine inches.

The obvious drawback of reusable cores formed in this manner is that they require a long assembly line, due to the need of a heater, and because the phenolic must be heated to a predetermined temperature, there is an obvious trade off between the number of heater stages and the speed of the line. Additionally, while the resulting rollers are termed reusable because they do not separate when placed in paint solvents, any prolonged exposure to such solvents, does result in breakdown of the paint roller and/or separation of the layers. Moreover, the manufacturing process for making phenolic core rollers is environmentally unfriendly.

Another reusable roller is disclosed in U.S. Pat. No. 4,692,975 issued to Garcia, wherein the roller is formed using a preformed core made of thermoplastic (e.g. polypropylene) tubular stock. In particular, the process disclosed mounting a preformed core on a rotating spindle, providing a carriage movable in a direction parallel to the spindle, and providing on the carriage a direct heat source and, at an angle to the spindle a continuous strip of fabric. The disclosed process consisted of igniting the direct heat source to begin heating the outer surface of the tubular stock and moving the carriage parallel to the spindle in timed relation to the spindle's rotation so that the fabric strip is wound on the heated portion of the plastic core in a tight helix. The heated portion of the plastic core was thereby heat-softened just in advance of the point where the fabric strip is applied, such that the fabric is bonded to the core as it is wound thereon. In effect, a portion of the polypropylene core surface is used as the bonding adhesive. One advantage of the roller disclosed in the Garcia patent is that the bond formed between cover and core is a strong one not easily subject to separation from exposure to paint solvents. Another advantage is that the manufacturing process does not require the application of a separate adhesive to bond the cover to the core. There are, however, drawbacks. For one, while prior art techniques use rolls of, e.g., chipboard or paper, the Garcia process requires preformed thermoplastic tubular cores which are considerably bulkier than rolls, more expensive to transport, and more difficult to handle. Another drawback is the anticipated speed limit of the Garcia process dictated by the necessity that the heater, which advances along the core just in front of the fabric strip, move slow enough to insure softening of the polypropylene core, in the absence of which the fabric cover will not bond. In addition, the application of direct heat to the preformed polypropylene core presents manufacturing hazards from the heat source and from the fumes and/or chemicals released during the heating process.

U.S. Pat. No. 5,195,242, which is incorporated herein by reference in its entirety, issued to one of the present inventors and resolved many of the foregoing problems by (i) forming the thermoplastic core on the fly instead of using preformed cores, and (ii) using preheated thermoplastic as a glue, both to form the core by applying it between the strips forming the core, and to affix the cover to the core by applying it to the outside of the core before wrapping the cover thereabout. The patent describes a process involving the wrapping of three strips of thermoplastic material (preferably polypropylene) around a mandrel in overlapping relation to form a core, the strips making the core are bonded together by applying a liquefied thermoplastic material (again, preferably polypropylene) thereto prior to wrapping them about the mandrel. After the core is thus formed a liquefied thermoplastic (again, preferably polypropylene) is applied to the outer surface of the core, and a cover wrapped thereupon. All that remains, as is well known, is to cut the resulting endless roller down to usable sizes, which, as described above may be accomplished in two steps, first using a fly away cutter to make longer lengths, and then using another cutter to cut the stock into usable lengths. While this process was capable of making high quality rollers that were substantially unaffected by paint solvents, the process involved the use of multiple strips of thermoplastic material and numerous points of application for liquefied thermoplastic. As a result, the process was difficult to set up, and required many continuous adjustments in its operation.

U.S. Pat. No. 5,468,207 issued to Bower discloses a continuous process using direct heat to bond the surface of the thermoplastic plastic strips instead of applying liquefied thermoplastic to the strips to bond them together. Bower also discloses using direct heat to the surface of the core to bond the cover rather than applying liquefied thermoplastic prior to applying the cover.

U.S. Pat. No. 5,572,790, which is incorporated herein by reference in its entirety, also issued to one of the present inventors, and resolved some of the complexity problems of the foregoing process. Under this process, which has become a de facto standard for roller manufacturing today, instead of forming a core by winding a plurality of strips in overlapping relation about a mandrel, and then affixing a cover thereto, it was disclosed to wind only a single strip about the mandrel, the adjacent edges thereby placed in a closely-spaced or abutting relation. A liquefied thermoplastic material (preferably, polypropylene) is then applied to the exposed surface of the wound strip, and a roller is formed by helically winding the cover over the liquefied material and the wound strip with sufficient tensile force so that the fabric cover lays smoothly thereupon. Again, as with other endless roller manufacturing, a fly-away cutter may be first used to cut the product into longer lengths, and then such lengths may be cut to usable lengths. This process represented an advance over the previous method invented by the present inventor because the entire paint roller was formed in a single step which made the assembly line easier to manage as there was only a single strip of material and a single application of liquefied thermoplastic. The resulting roller, however, is somewhat inferior. More specifically, a defect present in all such rollers, manifests itself as a weak point, often sticking out from the ends of a cut roller, or making the ends of the cut roller appear “out of round.” This results from the high tension memory of the strip which tends toward unwinding or toward “open” with high hoop strength. Moreover, to achieve the desirable hardened feel of the multi-layer rollers, the single strip rollers are generally made using a thicker plastic strip. The thicker the plastic strip used, (especially in relation to the diameter of the core) the more pronounced the memory effect appears on the roller.

U.S. Pat. No. 5,862,591 discloses another method of forming a paint roller in a single step. In this process, strips of thermoplastic are not used, and instead, a fluidized polypropylene is applied directly to a mandrel, and a cover is placed thereupon. The application of fluidized polypropylene to a mandrel has concomitant complications in synchronization and in the problems inherent in working with consistency of application of a fluidized layer in forming a polypropylene core. Like this process, other proposals have been made for placing the pile fabric on a heated core, as for example in French Patent Publication 2,093,060, in which pile fabric is placed on a hot, freshly extruded core. It is, however, believed that no such systems have the difficulties associated with controlling the shrinkage variation which inevitably occurs in the matching of what is essentially a through heated core blank or strip blank and a cold (i.e., room temperature, for example) pile fabric.

U.S. Pat. No. 6,159,134, which is incorporated herein by reference in its entirety, also issued to one of the present inventors, and represented an advance for making paint rollers having thermoplastic cores and a fully integrated cover that are formed in a single-step step continuous process from two polypropylene strips. Under this process, two strips of thermoplastic material are helically advanced about each other around a mandrel in an offset relation. Then, a cover is helically advanced about the second strip while providing an adhesive between the first strip and the second strip and between the outer surface of the strips and the cover. A continuous laminated paint roller is formed by applying a compressive force upon the cover.

U.S. patent application Ser. No. 12/200,734, also by the present inventor, which application is incorporated herein by this reference in its entirety, represented an advance for making paint rollers having thermoplastic cores and a fully integrated formed in a continuous process using one or more perforated strips.

U.S. patent application Ser. No. 12/147,472, in which the present inventor is a co-inventor, which application is incorporated herein by this reference in its entirety, represented an advance for making paint rollers having thermoplastic cores and a fully integrated cover formed in a continuous process from strips with grooves on a surface thereof.

SUMMARY OF THE INVENTION

In an embodiment, the invention includes a method of making a laminated paint roller wherein a perforated strip of thermoplastic material is advanced, the perforated strip having holes there-through. A lubricant is applied to the inner surface of the advancing perforated strip of thermoplastic material. The lubricated, perforated strip of thermoplastic material is helically wound around a cooled mandrel so as to form a helically wound strip wherein the inner surface of the perforated strip faces the cooled mandrel and the outer surface of the perforated strip faces away from the cooled mandrel. The wound perforated strip is advanced along the cooled mandrel. A layer of adhesive is applied onto an outer surface of the wound perforated strip. A strip of composite cover material is helically wrapped about the wound strip and over the layer of adhesive, the outer surface of the composite cover material comprising a pile fabric, and the inner surface of the composite cover material comprising thermoplastic. A compressive force is applied upon the composite cover material to urge the composite cover material, the layer of adhesive and strip of thermoplastic material together against the cooled mandrel, thereby laminating the inner surface of the composite cover material to the outer surface of the strip.

In another embodiment, the invention includes a method of making a composite cover material wherein a pile material is advanced. A first adhesive layer is applied to the underside of the pile material. A second adhesive layer is applied over the first adhesive layer, the second adhesive layer and the first adhesive layer being different adhesives. The first adhesive layer and the second adhesive layer are allowed to set. The pile on the pile side of the pile material is cut to the desired height. The composite sheet material is longitudinally cut to form one or more strips of composite cover material in a desired width, the outer surface of the composite cover material comprising a pile fabric, and the inner surface comprising thermoplastic.

The above and other objects, features and advantages of the embodiments will become more evident from the following discussion and drawings.

DETAILED DESCRIPTION OF THE INVENTION AND THE PREFERRED EMBODIMENTS

In the embodiment shown inFIG. 1, an apparatus1for forming the composite cover material17is shown. In an embodiment, the apparatus comprises a first adhesive applicator3, a first feeder4, a first adhesive supply5, an oven7, a second adhesive applicator9, a second feeder10, a second adhesive supply11, rollers14and cutters16. The composite cover material is formed using a continuous supply of pile material2such as would be suitable for use manufacturing a paint roller cover. Suitable pile material2may be used such as the material that can be manufactured using a sliver knitting machine such as the SK-18 available from Mayer Industries Inc. Such knitted pile material may be made “in the round,” and slit for use as a continuous pile material. Once slit, the knitted pile material can be laid flat for further processing. As an alternative to the knitted pile material, a woven pile material may be used, such a woven pile material, while generally more expensive than the knitted material, is advantageous as its fibers are locked in during the weaving process rather than by later application of an adhesive. The pile material2is usually sheared (not shown) on the pile side to attain a desired pile height. The material2can have any usable width, such as widths of approximately 32″ or 60″, and can be sheared to a desired pile height.

In an embodiment, the material2is laid flat using a tenter frame, and an adhesive layer6is applied thereto by the first adhesive applicator3. The first adhesive supply5supplies the first adhesive to the applicator3by first feeder4. In an embodiment, the first adhesive layer6is made predominantly or entirely from an emulsion in water of polyvinyl acetate. Such an emulsion is more commonly known as “white glue” and the yellow “carpenter's glue.” In an embodiment, the first adhesive layer may, but need not, additionally contain a filler such as clay.

The material2with the first adhesive layer6is allowed to set and bond to the material2which helps the pile hold fast and form stiffened fabric8. In an embodiment, setting of the first adhesive layer6can be hastened by passing the material2with the first adhesive layer6through an oven7such as an industrial oven to cause the first adhesive layer6to set and bond more quickly.

A second adhesive layer20is applied to the stiffened fabric8by the second adhesive applicator9. The second adhesive supply11supplies the second adhesive to the applicator9by a feeder10. In an embodiment, the second adhesive is made predominantly or entirely from polypropylene resin, the second adhesive applicator may be a die head and the supply11and feeder10are an extruder suitable for use to extrude polypropylene resin.

Before the second adhesive layer20can set, the stiffened fabric12with the second adhesive layer20thereon is fed, along with sheet material13, between rollers14or other apparatus that can provide a compressing force to urge the stiffened fabric and the sheet material13towards the second adhesive layer20and each other. In an embodiment the sheet material13is made predominantly or entirely from polypropylene.

After being compressed by the rollers14, combined sheet material15is advanced toward cutter16that is used to cut the sheet material15into composite cover material17. In an embodiment, the composite cover material is approximately 2⅞ inches wide, corresponding to a width of cover material that may typically be used to manufacture paint rollers. In an embodiment, the composite cover material is spooled and cut into usable lengths that can be transported for use at another site or on another machine performing a continuous manufacturing process for laminated paint rollers.

In an embodiment, the sheet material has a thickness of between 0.010″ and 0.030″, although thinner and thicker sheet material is believed to be applicable, and the use of such thinner or thicker sheet material is within the contemplated scope of the present invention. When used with pile material2having a width of approximately 32″, the width of the sheet material may be between about 31⅝″ and 32″. To manufacture eleven strips of composite cover material17that are 2⅞ inches wide, a width of at least 31⅝ inches is required, however, in an embodiment, using pile material2having a width of approximately 32″, the width of the sheet material13should be between approximately 31⅞″ and 32″ to allow for a relatively small amount of waste on each side of the combined sheet material15as is cut by the cutter16and thereby becomes composite cover material17.

While any width of pile material may be used, in an embodiment, a width of 60 inches is used to manufacture twenty strips of composite cover material17that are 2⅞ inches wide. In such an embodiment, the sheet material13is at least 57½″ wide but preferably wide enough to allow for a relatively small amount of waste on each side of the combined sheet material15as is cut by the cutter16and thereby becomes composite cover material17.

For ease of discussion in this application, the term “downstream” refers to the direction further along in the roller manufacturing process, or nearer the fly-away cutter3, while the term “upstream” refers to the direction earlier in the roller manufacturing process, or further from the fly-away cutter3.

Turning now toFIG. 2, a top view is shown of an apparatus for manufacturing the composite cover material17in accordance with an embodiment of the invention. The pile material2is fed to a first adhesive applicator3where a first adhesive layer6is applied to the non-pile surface of the material2. The first adhesive layer6is allowed to set and bond to the material2which helps the pile hold fast and form stiffened fabric8. The setting can, but need not be hastened by passing the material2with the first adhesive layer6through a heater7such as an industrial oven to cause the first adhesive layer6to set and bond more quickly.

In an embodiment, the stiffened fabric8can be spiral wound and cut into lengths of cover material and transported to another machine or location for further processing.

The second adhesive applicator9applies a second adhesive layer20to the stiffened fabric8, either on the line in which it is manufactured, or from spools of the stiffened fabric8. Before the second adhesive layer20can set, a sheet material13is applied and the stiffened fabric8, the second adhesive layer20and the sheet material13are urged together. In an embodiment, this urging can be provided by a pair of rollers14. In an embodiment each of the adhesive material20and the sheet material13are made predominantly or entirely from polypropylene.

Once the compressive force has been applied, and the second adhesive layer sets sufficiently, the combined sheet material15is advanced toward cutter16to form combine cover material17.

In an embodiment the material2is approximately 32″ wide, the sheet material13and adhesive layer20may be between 31⅝″ and 32″, and the composite cover material is 2⅞″ wide. In such an embodiment, a dozen separate blades can be used in the cutter16to form eleven strips of 2⅞″ each, and two small waste strips31.

Varying the width of the material2is within the scope of the invention, thus, in another embodiment, the material2is approximately 32″ wide, the sheet material13and adhesive layer20are between 31.675″ and 32″ wide, and the composite cover material is 2⅞″ wide. In such an embodiment,12separate blades can be used in a cutter to form11strips of2⅞″ each, and two small waste strips.

In an embodiment, the strip material is wound into spools (not shown) and delivered to another site or apparatus where paint rollers can be formed in a laminate process.

Turning now toFIG. 3, a diagrammatic representation of an apparatus40suitable for making laminated paint rollers in accordance with an embodiment of the invention is shown. Housing22supports mandrel21. As is known in the art, a cooler (not shown) can be used to cool the mandrel21. In an embodiment, inner strip23is feed about a the mandrel21, so it winds helically. The term helically as used herein means oriented about a mandrel21so as to permit the upstream edge of a given wind of a strip or cover material to be in closely-spaced or abutting relation with the downstream edge of the preceding wind of the strip. As is known in the art, a lubricant such as 5% mineral oil may be applied to the inner surface of the inner strip23prior to winding on the mandrel21.

The head24provides a layer of adhesive material25from a source of such material (not shown), the adhesive material25is preferably polypropylene. The source of adhesive material25is preferably an extruder, but may be any source of adhesive material including a melter. The head24may be any type of head appropriate for providing adhesive material25from the source, such as a nozzle or a die. Where the source of the adhesive material25is an extruder, the head24is preferably a die.

In an embodiment a single head24supplies an adhesive layer25to the outer surface of inner strip23as it rotates around the mandrel21. Although the width of the adhesive layer may be varied, in an embodiment, the width the adhesive layer25should substantially cover the outer surface of the inner strip23. The width of the adhesive layer25, however, may not completely cover the outer surface of the inner strip23, or may be sufficient to excess adhesive over the amount required to completely cover the outer surface of inner strip23. A strip of composite cover material17is advanced about the mandrel21outside of the inner strip23and adhesive layer25. In an embodiment, composite cover material17comprises a pile material2bonded to a backing made of, or compatible with, polypropylene.

The edges of the composite cover material17may be offset from the edges of the inner strip23as the two are advanced along the mandrel21. It is believed that the a stronger product is yielded from having an offset between the edge of the composite cover material17and the edge of the inner strip23. An offset of between about one-quarter (as shown) and three-quarters of the width of the inner strip23is found to achieve acceptable results. The best results are presently believed to be achieved by having an offset of about one-half of the width of the inner strip23.

Prior to the hardening and setting of the adhesive material25, an inwardly compressive force applies pressure to the outer surface of the composite cover material17, imparting inward forces on the component parts, thus laminating the composite cover material17and the inner strip23as the adhesive layer25sets. The continuous roller29is thereby formed about the mandrel21.

In an embodiment, the inwardly compressive force is a helical belt system formed from rollers28a,28b, and a belt28. In addition to compressing the component parts and forming the roller, the belt28advances the thus-formed endless roller29along the mandrel21and continuously rotates the endless roller, thereby also advancing the inner strip23and the composite cover material17around and downstream on the mandrel21.

As is known in the art, the endless roller29may be cut by the fly-away saw27, into lengths after it has sufficiently set. The fly-away saw27may be used to cut endless roller29into paint-roller sized lengths ready for finishing, or more typically into sticks26of a fixed length, such as 65″, that may be further cut and finished into paint-rollers.

It is within the scope of the invention to apply the adhesive layer25to the outer surface of the inner strip23, the inner surface of the composite cover material17, or simultaneously to the inner surface of the composite cover material17and the outer surface of the inner strip23, in any event, such that the adhesive layer25is sandwiched between the inner strip23and the composite cover material17.

In an embodiment, the head24is a die head, and the adhesive layer25is made predominantly or entirely from thermoplastic. An extruder (not shown) forces the thermoplastic through the head24, thereby applying liquefied thermoplastic as the adhesive layer25. In an embodiment, the thermoplastic is predominantly, or entirely, polypropylene.

Although laminated paint rollers have previously been disclosed, such as in co-inventor Chandra Sekar's U.S. Pat. No. 6,159,134, the previous lamination processes involved the use of two separate strips of thermoplastic material and a separate cover material, along with a wider head capable of spanning approximately twice the width of the inner strip. The greater number of materials, larger head (and thus, larger associated pressure and flow rate) make this prior process for manufacturing laminated paint rollers substantially more complex than the simple single step, on-the-fly process of the present invention.

Although making paint rollers using a single strip and a cover in a single step on-the-fly process has previously been disclosed, such as in co-inventor Chandra Sekar's U.S. Pat. No. 5,572,790, that process, which at the time thought to represent an advance over previous methods for manufacturing paint rollers because the entire paint roller was formed in a single step which made the assembly line easier to manage as there was only a single strip of material and a single application of liquefied thermoplastic, the resulting roller was somewhat inferior. More specifically, a defect present in all such rollers manifests itself as a weak point, often sticking out from the ends of a cut roller, or making the ends of the cut roller appear “out of round.” This results from the high tension memory of the single polypropylene strip which tends toward unwinding or toward “open” with high hoop strength. Thus, to achieve the desirable hardened feel of the multi-layer rollers, the single strip rollers would have to be made using a thicker plastic strip. The thicker the plastic strip used, (especially in relation to the diameter of the core) the more pronounced the memory effect appears on the roller.

In an embodiment: the inner strip23has a width of 2¾ inches, and a thickness of between about 0.010″ and 0.030″; the composite cover material17has approximately the same thickness, not counting the pile height, and a width of 2⅞ inches; and the adhesive layer is between 0.010 inches and 0.030 inches. Thicknesses selected from the higher values in these ranges will provide paint rollers that have a more rigid feel, while thicknesses selected from the lower values in the ranges will provide a paint roller that has a softer feel. It is within the scope of the invention to independently select each of the thicknesses from these ranges. The width and thickness of the inner strip23, and the width, non-pile thickness and pile thickness of the composite cover material17may be those that are appropriate for manufacture of the desired roller. For example, a typical high quality laminated roller having a 1.5-inch diameter core and a 75-wall can be manufactured with the following materials:

As used herein, the term “wall” or “mil” means thickness in thousandths of an inch. Such widths and thickness and the methods of determining them are known in the art. It will be apparent to one of skill in the art that almost infinite variation is possible depending upon the characteristics of the desired roller.

It is presently believed that the lamination process of the present invention will produce acceptable high quality rollers using less thickness, such as, a the laminated rollers having a 1.5-inch diameter core, which can be manufactured with any of the following combinations of materials:

Variations of this type with respect to the present invention will be apparent to one skilled in the art. The amount of adhesive, however, is expected to be less than typically required in a process bonding a thermoplastic strip to an ordinary paint roller cover, such as the process disclosed in co-inventor Chandra Sekar's U.S. Pat. Nos. 5,572,790 and 6,159,134. This is expected because, in this application, the adhesive layer bonds only the typically non-porous thermoplastic layers rather than the typically porous paint roller cover.

It is possible, without departing from the invention, to use more than one head to apply the second adhesive layer between the composite cover material17and the inner strip23. Regardless of the width or number of heads, in order to produce a quality laminated continuous roller, pressure must be applied inwardly upon the composite cover material17before the layer of polypropylene is permitted to harden and set.

In another embodiment (not shown), the composite cover material17can be directly fed from the machine producing it (e.g., no.1as shown inFIG. 1) into a paint roller manufacturing apparatus (e.g., no.40as shown inFIG. 2) for making laminated paint rollers. Where the is done in a continuous process that combines the compositing of the second adhesive layer20and the sheet material13, the speed of the process is likely to be far slower than the run rate of the apparatus shown inFIG. 2. It is within the scope of the invention to combine multiple composite cover material17strips, such as, for example, using a fly-away to cutter to cut the composite cover material17into fixed-length sections, and using a fastening means to attach the ends of such fixed-length sections as the composite cover material17is consumed by the manufacturing of paint rollers using a paint roller manufacturing apparatus40as shown inFIG. 2. In this manner, depending on the relative speed of the paint roller manufacturing apparatus40, the machine producing the composite cover sheet15, the manufactured width of composite cover sheet15and the desired width of composite cover material17, multiple paint roller manufacturing apparatus40can be supplied from one machine1making composite cover material17.

Turning now toFIG. 4A, an apparatus1A for forming composite cover material17A is shown. In an embodiment, the apparatus comprises an adhesive applicator9, a feeder10, an adhesive supply11, rollers14and cutters16. The composite cover material17A is formed using a continuous supply of pile material2such as would be suitable for use manufacturing a paint roller cover. The pile material2can be laid flat for processing. It is usually sheared (not shown) on the pile side to attain a desired pile height prior to processing by the machine1A. The material2can have any usable width, for example a width of approximately 32″ is suitable.

In an embodiment, an adhesive layer20is applied to the non-pile side of the material2by the adhesive applicator9. The adhesive supply11supplies the adhesive to the applicator9by a feeder10. In an embodiment, the adhesive is made predominantly or entirely from polypropylene resin, the adhesive applicator may be a die head and the supply11and feeder10are an extruder suitable for use to extrude polypropylene resin.

Before the adhesive layer20can set, the fabric2with the adhesive layer20thereon is fed, along with sheet material13, between rollers14or other apparatus that can provide a force to urge the fabric and the sheet material13and the adhesive layer20together. In an embodiment the sheet material13is made predominantly or entirely from polypropylene.

After being compressed by the rollers14, combined sheet material15A is advanced toward cutter16that is used to cut the sheet material15A into composite cover material17A. The rollers14may be cooled by a cooler (not shown) to hasten the setting of the adhesive layer20, and thus hasten the forming of the combined sheet material. In an embodiment, the composite cover material17A is approximately 2⅞ inches wide, corresponding to a width of cover material that may typically be used to manufacture paint rollers. The composite cover material17A may be spooled and cut into usable lengths that can be transported for use at another site or on another machine performing a continuous manufacturing process for laminated paint rollers. In an embodiment, composite cover material17A may be fed directly to an apparatus performing a manufacturing process for laminated paint rollers, such as feeding composite cover material17A as composite cover material17to the apparatus40shown inFIG. 3.

In an embodiment, the sheet material13has a thickness of between 0.010″ and 0.030″, although thinner and thicker sheet material is believed to be applicable, and the use of such thinner or thicker sheet material is within the contemplated scope of the present invention. When used to manufacture eleven strips of composite cover material17that are 2⅞ inches wide, the pile material2should having a width of approximately 32″, and the sheet material13should be between about 31⅝″ and 32″ wide. Increasing the width of the sheet material13to allow for a relatively small amount of waste on each side of the combined sheet material15A as is cut by the cutter16and thereby becomes composite cover material17A has been found to produce superior results.

Turning now toFIG. 4B, which shows a detail of a portion of the side-view of the apparatus1A inFIG. 4Ain an embodiment using a grooved sheet material13B. A head9applies a layer of adhesive20to the material2. The grooved sheet material13may be grooved on one or both sides, as discussed in U.S. patent application Ser. No. 12/147,472 to the instant inventors. In the embodiment shown, grooves are only on one side of the grooved sheet material13B. The grooves are oriented so as to be exposed after the adhesive layer20sets, and the material2and the grooved sheet material13B are integrated to form the grooved composite sheet material15B. The composite sheet material15B can be cut into the grooved composite cover material17B by the cutter16.

Turning toFIG. 5, there is a cutaway view of the apparatus40shown inFIG. 3in an embodiment using grooved composite cover material17a. The inner strip23is fed around mandrel21. The grooved composite cover material17ais applied over an application of an adhesive layer (not shown). It is believed that as the grooved composite cover material17ais helically wound, the grooves become smaller, and the adhesive of the adhesive layer occupies all or substantially all of the remaining space of the groove. Before the adhesive layer (not shown) can set, a compressive force is applied (e.g., by a belt, also not shown) causing the grooved composite cover material17ato laminate around the inner strip23. To the extent that the grooves are not occupied by the adhesive of the adhesive layer before the compressive force is applied, it is believed that the compressive force also urges the adhesive of the adhesive layer further into the grooves.

FIG. 6shows a diagrammatic representation of an apparatus40suitable for making laminated paint rollers in accordance with an embodiment of the invention. The strip of composite cover material17bdiffers from the composite cover material17shown inFIG. 1because the sheet material (not shown) used to make the composite cover material17bwas perforated prior to being brought into contact with the second adhesive layer (20,FIG. 1). A purpose of the perforation is to use a lower weight of sheet material because sheet material such as polypropylene sheet material as may be advantageously used in connection with the present invention is generally sold by weight. Accordingly, the perforations may take on varying sizes and shapes as is appropriate to reduce material weight without adversely affecting the usability of the paint roller manufactured therewith. A discussion of various sizes and shapes of perforations that can be used in strip material is presented in U.S. patent application Ser. No. 12/200,734, which has been incorporated herein.

In an embodiment, a rotary die can be used to perforate the thermoplastic sheet material during for the process of making composite cover material. Alternatively, sheet material can be perforated in a separate process prior to manufacture of the composite cover material, or it can be purchased pre-perforated.

Turning now toFIG. 7, an apparatus701for forming the composite cover material717is shown. In an embodiment, the apparatus comprises a first adhesive applicator703, a first feeder704, a first adhesive supply705, a first heater707, a second adhesive applicator709, a second feeder710, a second adhesive supply711, a second heater719, pile cutter718and strip cutter716. The composite cover material is formed using a continuous supply of pile material702such as would be suitable for use manufacturing a paint roller cover. The material702can have any usable width, for example, a width of approximately 32″ or 60″.

In an embodiment, the material702is laid flat. A tenter frame may be used for this purpose. An adhesive layer706may be applied thereto by the first adhesive applicator703. The first adhesive supply705supplies the first adhesive to the applicator703by first feeder704. In an embodiment, the first adhesive layer706is made predominantly or entirely from an emulsion in water of polyvinyl acetate. Such an emulsion is more commonly known as “white glue” and the yellow “carpenter's glue.”

The first adhesive layer706may be allowed to set and bond to the material702which helps the pile hold fast and form stiffened fabric708before the application of the second adhesive layer720, or may only be permitted to partially set prior to such application. In an embodiment, setting of the first adhesive layer706and its bonding to the material702can be hastened by passing the material702with the first adhesive layer706through the first heater707such as an industrial oven set to an appropriate temperature for setting the adhesive, but not so hot as to melt the material702.

The second adhesive layer720is applied to the stiffened fabric708by the second adhesive applicator709. The second adhesive supply711supplies the second adhesive to the applicator709by a feeder710. In an embodiment, the second adhesive is made predominantly or entirely from polypropylene resin, the second adhesive applicator may be a die head and the supply711and feeder710are parts of an extruder suitable for use to extrude polypropylene resin.

The stiffened material708with the second adhesive layer720thereon is allowed to set and bond. In an embodiment, the combination712of the stiffened fabric708with the second adhesive layer720thereon is fed through the second heater719to form the composite sheet material715. The second heater719may better integrate the second adhesive layer720and the stiffened fabric708. The application of heat may even or smooth the exposed surface of the adhesive layer720, and may permit the adhesive in the adhesive layer720to fill interstitial spaces or gaps within the stiffened material708.

The composite sheet material715is advanced over cutter716to form composite cover material717. As discussed above, the cutter716may be used to cut the composite sheet material715into strips of composite cover material717in a desired width. It is not necessary that all of the strips of composite sheet material715are cut into equal widths. It is within the scope of this invention to cut differing width composite cover material717from a single composite sheet material715, for example, by varying the spacing of the cutting edges of the cutter716.

In an embodiment (not shown) cooling may be applied to the composite sheet material715, or to the composite cover material717, to hasten the setting of the second adhesive layer720.

In an embodiment, the composite cover material is approximately 2⅞ inches wide, corresponding to a width of cover material that may typically be used to manufacture paint rollers. The composite cover material717may be spooled and cut such that it can be transported for use at another site or on another machine performing a continuous manufacturing process for laminated paint rollers.

The pile of stiffened fabric708may be cut to a desired size by a pile cutter718. The pile may be cut before or after the application of the first adhesive layer706, and before or after the application of the second adhesive layer720, but is preferably cut before the longitudinal cutter716is used to cut the composite sheet material715into composite cover material717.

Turning now toFIG. 8A, an apparatus801A for forming the composite cover material817is shown. In an embodiment, the apparatus comprises an adhesive applicator809, a feeder810, an adhesive supply811, an environmental control807and strip cutter816.

The composite cover material817is formed using a supply of pile material802such as would be suitable for use manufacturing a paint roller cover. Pile material802is a type suitable for use as a paint roller, and in an embodiment may be knitted or woven material. The material802can have any usable width, for example, a width of approximately 32″ or 60″.

The material802is laid flat, in an embodiment, a tenter frame (not shown) can be used for this purpose. An adhesive layer820is applied to the fabric by the adhesive applicator809. The adhesive supply811supplies the adhesive to the applicator809via a feeder810. In an embodiment, the adhesive is made predominantly or entirely from polypropylene resin, the adhesive applicator809may be a die head and the supply811and feeder810are parts of an extruder suitable for use to extrude polypropylene resin.

The setting of the adhesive layer and/or the bonding between the adhesive layer820and the material802may be affected by control of the environment (e.g., the application of heating or cooling) after the adhesive820is dispensed from the applicator809but before it has set fully. It is within the scope of the invention to permit the setting of the adhesive layer820and its bonding to the material802naturally, or through the use of environmental intervention.

In an embodiment, after the application of the adhesive layer820the material812can be optionally fed through an environmental control807to form the composite sheet material815. The environmental control807may be used to affect the bond between the adhesive layer820to the underlying material802, and aid in integrating the adhesive layer820with the material802. In an embodiment using an environmental control807, the control807may employ the application of heat, which may even or smooth the exposed surface of the adhesive layer820, and may permit the adhesive in the adhesive layer820to better fill interstitial spaces or gaps within the material802. In another embodiment using an environmental control807, the control807may employ cooling, such cooling can hasten the hardening or setting of the adhesive layer820. It is within the scope of the invention to employ an environmental control807that utilizes the application of heat and the application of cold, seriatim, which may achieve, among other things, one or more of the following: (i) even or smooth the exposed surface of the adhesive layer820; (ii) permit the adhesive in the adhesive layer820to better fill interstitial spaces or gaps within the material802; and/or (iii) hasten the hardening or setting of the adhesive layer820.

Whether or not an environmental control807is employed, the composite sheet material815is advanced across cutter816to form composite cover material817. As discussed above, the cutter816may be used to cut the composite sheet material815into strips of composite cover material817in a desired width. The strips of composite sheet material815do not need to be cut to equal widths. It is within the scope of this invention to cut differing width composite cover material817from a single composite sheet material815, for example, by varying the spacing of the cutting edges of the cutter816.

In an embodiment, the strips of composite cover material817each have a width of approximately 2⅞ inches, corresponding to a width of cover material that may typically be used to manufacture paint rollers. The composite cover material817may be spooled and cut such that it can be transported for use at another site or on another machine performing a continuous manufacturing process for laminated paint rollers. In another embodiment, the composite cover material may be feed directly to an apparatus that uses the material in forming laminated paint rollers. Where the composite cover material is spooled, it may be desirable to spool the composite cover material817while it is still warm and pliable, alternatively, it may be desirable to ensure that the composite cover material817is fully cooled (i.e., not warm and pliable) when it is spooled.

If the pile on material802has not been sheared to the desired height prior to the application of the adhesive layer820, it may be cut by a pile cutter (not shown) after application of the layer820.

Turning now toFIG. 8B, an apparatus801B for forming the composite cover material817is shown. In an embodiment, the apparatus comprises an adhesive applicator809, a feeder810, an adhesive supply811, cooling rollers850and strip cutter816. After the adhesive layer820leaves the applicator809, but before it contacts the material802, the cooling rollers850cool and smooth the adhesive layer820to form a smoothed adhesive layer851. In an embodiment where the adhesive is polypropylene, although smoothed adhesive layer851is cooler than it was in its molten form leaving applicator809, it is still not hardened or set. Thus, after the smoothed adhesive layer851contacts the material802, it can harden and set forming the composite sheet material815. The composite sheet material815may be cut by cutter816to form the composite cover material817.

Turning now toFIG. 8C, an apparatus801B for forming the composite cover material817is shown. In an embodiment, the apparatus comprises an adhesive applicator809, a feeder810, an adhesive supply811, cooling rollers860and strip cutter816. After the adhesive layer820leaves the applicator809and contacts the material802, the cooling rollers860that are lower in temperature than the adhesive layer820apply a compressive force compressing the adhesive layer820and the material802together to form the composite sheet material. The composite sheet material815may be cut by cutter816to form the composite cover material817.

Turning now toFIG. 8D, an apparatus801D for forming the composite cover material817is shown. In an embodiment, the apparatus comprises an adhesive applicator809, a feeder810, an adhesive supply811, cooling rollers850, rollers852and strip cutter816. After the adhesive layer820leaves the applicator809, but before it contacts the material802, the cooling rollers850cool and smooth the adhesive layer820to form a smoothed adhesive layer851. In an embodiment where the adhesive is polypropylene, although smoothed adhesive layer851is cooler than it was in its molten form leaving applicator809, it is still not hardened or set. After the smoothed adhesive layer851contacts the material802, the rollers852apply a compressive force compressing the smoothed adhesive layer851and the material802together to form the composite sheet material. The composite sheet material815may be cut by cutter816to form the composite cover material817.

In an embodiment, the rollers852are heated to a temperature hotter than the temperature of smoothed adhesive layer851. In an embodiment, the rollers852are cooled to a temperature cooler than the temperature of the smoothed adhesive layer851. In an embodiment, the rollers852are neither heated nor cooled.

Turning now toFIG. 8E, an apparatus801E for forming the composite cover material817is shown. In an embodiment, the apparatus comprises an adhesive applicator809, a feeder810, an adhesive supply811, cooling rollers850, heating rollers855, second cooling rollers860and strip cutter816. After the adhesive layer820leaves the applicator809, but before it contacts the material802, the cooling rollers850cool and smooth the adhesive layer820to form a smoothed adhesive layer851. In an embodiment where the adhesive is polypropylene, although smoothed adhesive layer851is cooler than it was in its molten form leaving applicator809, it is still not hardened or set. After the smoothed adhesive layer851contacts the material802, the heating rollers852apply a compressive force compressing the smoothed adhesive layer851and the material802together while at the same time imparting heat to the combination. The second cooling rollers860thereafter apply a compressive force compressing the smoothed adhesive layer851and the material802together, while at the same time cooling them. It is believed that the heating by rollers852may aid in filling fill interstitial spaces or gaps within the material802with contacting side of the smoothed adhesive layer851, and that the cooling by the second cooling rollers860may hasten the setting of the smoothed adhesive layer. The resulting composite sheet material815may be cut by cutter816to form the composite cover material817.

Turning now toFIG. 9A, a diagrammatic representation is shown of an apparatus900suitable for making laminated paint rollers in accordance with an embodiment of the invention. The apparatus900and process of using the apparatus900are similar to the apparatus40(FIG. 2) and its processes. Housing22supports mandrel21. The head24provides a layer of adhesive material25from a source of such material (not shown), the adhesive material25is preferably polypropylene. The source of adhesive material25is preferably an extruder, but may be any source of adhesive material including, e.g., a melter. The head24may be any type of head appropriate for providing adhesive material25from the source, such as a nozzle or a die, however, where the source of the adhesive material25is an extruder, the head24is preferably a die. As is known in the art, a cooler (not shown) can be used to cool the mandrel21. As is also known in the art, a lubricant such as 5% mineral oil may be applied to the inner surface of the inner strip23prior to winding on the mandrel21.

In an embodiment a single head24supplies an adhesive layer25to the outer surface of inner strip23as it rotates around the mandrel21. Although the width of the adhesive layer may be varied, in an embodiment, the width the adhesive layer25should substantially cover the outer surface of the inner strip23. The width of the adhesive layer25, however, may not completely cover the outer surface of the inner strip23, or may be sufficient to provide excess adhesive over the amount required to completely cover the outer surface of inner strip23. A strip of composite cover material817(see, e.g.,FIG. 8) is advanced about the mandrel21outside of the inner strip23and adhesive layer25. Composite cover material817comprises a pile material802bonded to a backing made of, or compatible with, polypropylene.

The edges of the composite cover material817may be offset from the edges of the inner strip23as the two are advanced along the mandrel21. It is believed that the a stronger product is yielded from having an offset between the edge of the composite cover material17and the edge of the inner strip23. An offset of between about one-quarter and three-quarters of the width of the inner strip23is found to achieve acceptable results. The best results are presently believed to be achieved by having an offset of about one-half (as shown) of the width of the inner strip23.

Prior to the hardening and setting of the adhesive material25, a compressive force applies pressure to the outer surface of the composite cover material817, imparting inward forces on the component parts, and laminating the composite cover material817and the inner strip23as the adhesive layer25sets. The continuous roller929is thereby formed about the mandrel21. The continuous roller929can be cut to usable lengths926by fly-away saw27.

Turning now toFIG. 9B, a diagrammatic representation is shown of an apparatus900suitable for making laminated paint rollers in accordance with an embodiment of the invention. The apparatus900is the same as shown inFIG. 9A, and the process of using the apparatus is similar to the process described in connection withFIG. 9A, except in the use of a perforated inner strip923. Co-pending U.S. patent application Ser. No. 12/200,734, also by the present inventor, contains a discussion of the possible variations in perforation, all of which may be used within the scope of the invention herein.

Although many variations are possible, in an embodiment using a perforated inner strip923made predominantly or entirely from polypropylene, the inventor has found that generally round, relatively small perforations, such as perforations of approximately ⅛ inch perform adequately to permit the prevent the adhesive layer25from having excessive contact with, or imparting excessive heat to, the mandrel21. As is known in the art, a cooler (not shown) can be used to cool the mandrel21, and in the described embodiment such a cooler may assist in preventing the adhesive layer25from sticking to the mandrel21. As is well known in the art, a lubricant such as 5% mineral oil (not shown) may be applied to the inner surface of the inner strip23prior to winding on the mandrel21, and in the described embodiment such a lubricant may assist in preventing the adhesive layer25from sticking to the mandrel21. A purpose for the perforation is to lower the total weight of strip material employed in making the laminated roller. Strip material such as polypropylene strips as may be advantageously used in connection with the present invention is generally sold by weight, and thus lowering the weight of strip material may reduce the overall cost of the laminated paint roller. As discussed in more detail in co-pending U.S. patent application Ser. No. 12/200,734, it has been found that the use of perforated strip material generally does not increase the amount of polypropylene resin required to form a laminated paint roller, and in some cases actually permits the use of less polypropylene resin, thereby further reducing the cost of manufacturing a laminated polypropylene roller.

After the application of the adhesive layer, composite cover material817is wrapped about the mandrel, over the perforated inner strip923and the adhesive layer925. Thereafter, but prior to the hardening and setting of the adhesive material25, a compressive force applies pressure to the outer surface of the composite cover material817, imparting inward forces on the component parts, and laminating the composite cover material817and the perforated inner strip923as the adhesive layer25sets. The continuous roller929is thereby formed about the mandrel21. The continuous roller929can be cut to usable lengths926by fly-away saw27.

It is further within the scope of the present invention, although not diagrammatically represented, to make laminated paint rollers on the apparatus900using the perforated inner strip923and composite cover material17b(seeFIG. 6). Such combinations may further lower the total weight of sheet material used in, and thus, the total price of, paint roller production.

In an embodiment, the inner strip923can be perforated by the use of an in-line rotary die (not shown) as the material moves to the Mandrel21. Alternatively, the inner strip923can be perforated in a separate process prior to manufacture of the laminated paint roller, or the inner strip923can be purchased pre-perforated.

Turning now toFIG. 10, a diagrammatic representation of an apparatus suitable for making laminated paint rollers in accordance with an embodiment of the invention is shown. In an embodiment, the apparatus comprises an adhesive applicator1009, a feeder1010, an adhesive supply1011and cutters1016. The composite cover material1017is formed using a continuous supply of pile material1002such as would be suitable for use manufacturing a paint roller cover. The pile material1002is laid flat for processing. Such material1002is usually sheared (not shown) on the pile side to attain a desired pile height prior to processing by the machine1000. The material1002can be in any convenient width. In an embodiment, material1002has a width of approximately 32″.

In an embodiment, an adhesive layer1020is applied to the non-pile side of the material1002by the adhesive applicator1009. The adhesive supply1011supplies the adhesive to the applicator1009by a feeder1010. In an embodiment, the adhesive is made predominantly or entirely from polypropylene resin, the adhesive applicator may be an extruder to extrude polypropylene resin, the extruder comprising a die head1009and the supply1011and feeder1010.

After the adhesive layer1020is applied to the non-pile side of the material1002, it is allowed to cool and set. Such cooling and setting can be hastened by a cooling system (not shown) which can impart cooling to the combined material1015by any method, including, without limitation, a cooled roller or the flow of cool air or other gas or fluids. In an embodiment, the adhesive layer1020comprises predominantly or entirely polypropylene. The fibers in the material1002are further held in place by the adhesive layer1020as it cools and sets.

Either before or after the applied adhesive layer1020is completely set, the combined material1015is advanced toward a cutter1016. The cutter1016is used to cut the combined material into strips of composite cover material1017having a pile side and a side predominantly or entirely made of polypropylene. In an embodiment, the strips of composite cover material are each approximately 2⅞ inches wide, corresponding to a width of cover material that may typically be used to manufacture paint rollers.

To manufacture eleven strips of composite cover material1017each being 2⅞ inches wide, the pile material2should having a width of approximately 32″. This width allows for a relatively small amount of waste on each side of the combined material1015as is cut by the cutter1016and thereby becomes composite cover material1017.

Although the combined cover material1015, or the strips of composite cover material1017can be spooled and cut (not shown) for transportation to another site or another machine performing a continuous manufacturing process for laminated paint rollers, in an embodiment, the composite cover material1017is fed directly to a mandrel1021. Housing1022supports mandrel1021. As is known in the art, a cooler (not shown) can be used to cool the mandrel1021. An inner strip1023is feed about a the mandrel1021, so it winds helically. In an embodiment, the inner strip is perforated polypropylene.

The head1024provides a second layer of adhesive material1024from a source of such material (not shown) delivered to the head1024. The adhesive material1024is preferably polypropylene. The polypropylene material is preferably supplied an extruder (not shown). The head1024may be any type of head appropriate for providing adhesive material1025from the source, such as a nozzle or, where an extruder is used, a die.

In an embodiment a single head1024supplies an adhesive layer1025to the outer surface of inner strip1023as it rotates around the mandrel1021. Although the width of the adhesive layer may be varied, in an embodiment, the width the adhesive layer1025should substantially cover the outer surface of the inner strip1021. The width of the adhesive layer1025, however, may not completely cover the outer surface of the inner strip1021, or may be sufficient to provide excess adhesive over the amount required to completely cover the outer surface of inner strip1021. The strip of composite cover material1017is advanced from the cutter1016about the mandrel1021outside of the inner strip1023and adhesive layer1025.

The edges of the composite cover material1017may be offset from the edges of the inner strip1023as the two are advanced along the mandrel1021. It is believed that the a stronger product is yielded from having an offset between the edge of the composite cover material1017and the edge of the inner strip1023. An offset of between about one-quarter (as shown) and three-quarters of the width of the inner strip1023is found to achieve acceptable results. The best results are presently believed to be achieved by having an offset of about one-half of the width of the inner strip1023.

Prior to the hardening and setting of the adhesive material1025, an inwardly compressive force applies pressure to the outer surface of the composite cover material1017, imparting inward forces on the component parts, thus laminating the composite cover material1017and the inner strip1021as the adhesive layer1025sets. The continuous roller1029is thereby formed about the mandrel1021.

In an embodiment, the inwardly compressive force is a helical belt system formed from rollers1028a,1028b, and a belt1028. In addition to compressing the component parts and forming the roller, the belt1028advances the thus-formed endless roller1029along the mandrel1021and continuously rotates the endless roller, thereby also advancing the inner strip1023and the composite cover material1017around and downstream on the mandrel1017.

As is known in the art, the endless roller1029may be cut by the fly-away saw1027, into lengths after it has sufficiently set. The fly-away saw1027may be used to cut endless roller1029into paint-roller sized lengths ready for finishing, or more typically into sticks1026of a fixed length, such as 65″, that may be further cut and finished into paint-rollers.

Although many variations are possible, in an embodiment using a perforated inner strip1023made predominantly or entirely from polypropylene, the inventor has found that generally round, relatively small perforations, such as perforations of approximately ⅛ inch perform adequately to permit the prevent the adhesive layer1025from having excessive contact with, or imparting excessive heat to, the mandrel1021. As is known in the art, a cooler (not shown) can be used to cool the mandrel1021, and in the described embodiment may assist in preventing the adhesive layer1025from sticking to the mandrel1021. As is well known in the art, a lubricant such as 5% mineral oil may be applied to the inner surface of the inner strip1023prior to winding on the mandrel1021, and in the described embodiment may assist in preventing the adhesive layer1020from sticking to the mandrel1021.

One purpose for the perforation is to use a lower total weight of polypropylene strip material because material such as polypropylene strip material, as may be advantageously used in connection with the present invention, is generally sold by weight.

The inner strip1023can be perforated by the use of an in-line rotary die (not shown) as the material moves to the mandrel1021. Alternatively, the thermoplastic (e.g., polypropylene) strips can be perforated in a separate process prior to manufacture of the laminated paint roller, or the strips can be purchased pre-perforated.

It is within the scope of the invention to apply the adhesive layer1025to the outer surface of the inner strip1023, the inner surface of the composite cover material1017, or simultaneously to the inner surface of the composite cover material1017and the outer surface of the inner strip1023, in any event, such that the adhesive layer1025is sandwiched between the inner strip1023and the composite cover material1017.

In an embodiment, the head1024is a die head, and the adhesive layer1025is made predominantly or entirely from thermoplastic. An extruder (not shown) forces the thermoplastic through the head1024, thereby applying liquefied thermoplastic as the adhesive layer1025. In an embodiment, the thermoplastic is predominantly, or entirely, polypropylene.

A benefit of the instant invention is that a high quality laminated roller can be produced using a narrow head and two strip-type supplies, namely, a single strip of thermoplastic, e.g., polypropylene, and a composite cover material, e.g., with a polypropylene backing. It is expected that such a simplified process will be easier and more cost efficient to operate, and will likely be able to produce rollers faster than multi-strip lamination processes. Another benefit of the present invention is that it can create a paint roller using a narrow head and only two strip-type supplies without the well known defect present in such rollers that manifests itself as a weak point, often sticking out from the ends of a cut roller.

The above embodiments and preferences are illustrative of the present invention. It is neither necessary, nor intended for this patent to outline or define every possible combination or embodiment. The inventor has disclosed sufficient information to permit one skilled in the art to practice at least one embodiment of the invention, and has disclosed the ways the inventor now believes are the best ways to practice the invention. The most obvious variations to the present invention include variation in the size and shape of the groove and variations in the pattern and placement of the grooves. It is understood that the above description and drawings are merely illustrative of the present invention and that changes in components, structure and procedure are possible without departing from the scope of the present invention as defined in the following claims.