CA2332142A1

CA2332142A1 - Mechanical and chemical embossed surface covering field of the invention

Info

Publication number: CA2332142A1
Application number: CA 2332142
Authority: CA
Inventors: William M. Mcquate; William J. Kauffman; Craig Brossman
Original assignee: Armstrong World Industries Inc
Current assignee: Armstrong World Industries Inc
Priority date: 2000-01-27
Filing date: 2001-01-25
Publication date: 2001-07-27

Abstract

Surface coverings with mechanical and chemical embossing, and methods of manufacture thereof, are disclosed. The surface coverings include a substrate, a foam layer disposed on the substrate, wherein the foamed layer has a chemically embossed pattern imposed therein, a wear layer disposed on the foam layer, and a mechanically embossed, cross-linked top layer disposed on the wear layer. In one embodiment, a web is formed including a substrate, a curable wear layer, an expandable foam layer between the substrate and the wear layer, and at least one inhibitor composition disposed as a pattern proximate the foam layer. The wear layer is coated with a cross-linkable top coat and then heated to a temperature at which the top coat is substantially cross-linked and cured, the wear layer is substantially cured, the foam layer substantially expands, and the pattern is chemically embossed to form a surface covering. Thereafter, the surface covering is tempered to a temperature above ambient temperature. The top coat is then heated and at least one surface texture is mechanically embossed and set thereon. The mechanical embossing can be performed in register with a printed or chemically embossed pattern of the surface covering. In one embodiment, the surface covering lacks the top coat and the wear layer is mechanically embossed.

Description

MECHANICAL AND CHEMICAL EMBOSSED SURFACE COVERING
FIELD OF THE INVENTION
This invention relates generally to surface coverings. In particular, this invention relates to a mechanical and chemical embossed surface covering and a method of making same.
BACKGROUND OF THE INVENTION
Decorative laminate surface coverings having textured surfaces and the methods of making such surface coverings are known. For example, such surface coverings are commonly patterned to duplicate a look of actual wood, tile, brick, stone, and other such products. Typically, the texture is either mechanically embossed by pressing a pattern into the surface covering or chemically embossed into an expanded foam layer disposed within the structure of the surface covering by foam retarding agents. Although these methods provide attractive decorative surface coverings, they are limited in their capability to replicate the appearance of the actual product. Examples of mechanical embossing methods are discussed in U.S. Patent Nos. 3,655,312, 3,887,678, and 3,953,639. Chemical embossing methods are, for example, discussed in U.S. Patent Nos. 3,293,108 and 5,643,677.
There has been and continues to be a demand by consumers for surface coverings that have a "more realistic" appearance to the actual product. In response, the manufacturers combined both techniques of chemical embossing and mechanical embossing to produce a surface covering. For example, U.S. Patent No.
4,022,643 to Clark ("Clark") discloses using a chemically embossed vinyl structure (with or without a wear layer attached) as a continuous embossing belt to mechanically texture a chemically embossed product with a wear layer. Clark indicates that there is a need for sharper embossing (achieved by mechanical embossing rolls) on chemically embossed products, but a lower embossing tooling cost. Clark discloses using a continuous chemically embossed embossing belt to texture the wear layer of a flooring product as an economical alternative to etched embossing rolls.

RTP 35096v1 _ _ ~_.~_.~ w...._.

Eby et al. ("Eby") in U.S. Patent No. 5,961,903 disclose a method of making a surface covering which is both chemically and mechanically embossed. In this method, a backing layer is coated with a foamable layer, and the foamable layer then receives a print layer thereon. Eby states that the print layer forms a design and a portion of the design is formed with a retarder composition. A thermoplastic wear layer is applied onto the print layer and cured by heat at a temperature sufficiently high to expand the foamable layer. The areas of the design layer where the retarder composition is applied are also chemically embossed during such curing.
Thereafter, Eby requires that this chemically embossed structure cool to ambient temperature before any further handling. Upon reaching ambient temperature, the cured thermoplastic wear layer is softened by heating. The wear layer is then mechanically embossed to have a surface texture. Optionally, a top coat, also known as a wear layer top coat, is applied to and adhered to the mechanically embossed wear layer.
Despite existing methods of making chemically and mechanically embossed surface coverings, there is a need for a surface covering which has a chemically embossed foam layer and a mechanically embossed top coat wear layer. Further, there remains a need for a method of making such a surface covering.
Additionally, there remains a need for a method of making such a surface covering which does not require cooling a preform comprising a substrate, a chemically embossed foam layer, and a wear layer to ambient temperature prior to mechanically embossing the wear layer. Still, there remains a need for a method of making such a surface covering which does not require cooling a preform comprising a substrate, a chemically embossed foam layer, a wear layer, and a top coat wear layer to ambient temperature prior to mechanically embossing the top coat wear layer. It is to the provision of a mechanical and chemical embossed surface covering and method of making the same that meets these needs that the present invention is primarily directed.
SUMMARY OF THE INVENTION
Briefly described, the present invention comprises a method of manufacturing a mechanical and chemical embossed surface covering. In one embodiment of the RTP 3509Gv1 present invention, a web is formed comprising a substrate, a curable wear layer, an expandable foam layer between the substrate and the wear layer, and at least one inhibitor composition disposed as a pattern proximate the foam layer. The wear layer is coated with a cross-linkable top coat to form a coated web and then heated to a temperature at which the top coat is substantially cross-linked and cured, the wear layer is substantially cured, the foam layer substantially expands, and the pattern is chemically embossed to form a surface covering. Thereafter, the surface covering is tempered to a temperature above ambient temperature. The top coat is then heated and at least one surface texture is mechanically embossed onto the top coat.
Upon setting the at least one surface texture, the mechanical and chemical embossed surface covering is formed. In addition, mechanical embossing includes mechanical embossing in register with a printed or chemically embossed pattern of the surface covering.
Another aspect of the present invention relates to a method of manufacturing a mechanical and chemical embossed surface covering that has a mechanically embossed wear layer. In this embodiment, a web is formed comprising a substrate, an expandable foam layer operably connected to the substrate, and at least one inhibitor composition disposed as a pattern proximate the foam layer. The foam layer is coated with a wear layer to form a coated web and then heated to a temperature at which the wear layer is substantially cured, the foam layer substantially expands, and the pattern is chemically embossed to form a surface covering. Thereafter, the surface covering is tempered to a temperature above ambient temperature. The wear layer is then heated and at least one surface texture is mechanically embossed onto the wear layer.
Upon setting the at least one surface texture, the mechanical and chemical embossed surface covering is formed. In addition, mechanical embossing includes mechanical embossing in register with a printed or chemically embossed pattern of the surface covering.
Yet, another aspect of the present invention relates to a chemically and mechanically embossed surface covering comprising a substrate; a foam layer disposed on the substrate, wherein the foamed layer has a chemically embossed RTP 35096v1 pattern imposed therein; a wear layer disposed on the foam layer; and a mechanically embossed, cross-linked top layer disposed on the wear layer.
A significant advantage of the present invention over existing surface coverings is that the mechanical and chemical embossed surface covering can be manufactured without cooling the expanded foam layer to ambient temperature at any stage of production. Further, a top coat comprising a cross-linkable resinous composition on a chemically embossed structure can be mechanically embossed.
Also, a chemically embossed structure can be mechanically embossed in register with a printed and/or chemically embossed pattern to provide more than one mechanically embossed surface texture.
In one embodiment, a first mechanically embossed texture is applied to a first region of the top coat or wear layer and a second mechanically embossed texture applied to a second region of the top coat or wear layer.
Thus, a unique mechanical and chemical embossed surface covering and 1 S method of manufacturing such surface covering is now provided that successfully addresses the shortcomings of and provides distinct advantages over existing surface coverings and their methods of manufacture. Additional obiects, features. and advantages of the invention will become more apparent upon review of the detailed description set forth below when taken in conjunction with the accompanying drawing figures, which are briefly described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic view of an embodiment of a process for manufacturing a mechanical and chemical embossed surface covering of the present invention.
Fig. 2 is a schematic view of another embodiment of a process for manufacturing a mechanical and chemical embossed surface covering of the present invention.
Fig. 3 is a partial cross sectional and elevation view of an embodiment of a mechanical and chemical embossed surface covering made in accordance with the process of Fig. I .

RTP 35096v1 Fig. 4 is a partial cross sectional and elevation view of an embodiment of a mechanical and chemical embossed surface covering made in accordance with the process of Fig. 2.
Fig. 5 is a partial cross sectional and elevation view of another embodiment of a mechanical and chemical embossed surface covering made in accordance with the process of Fig. 2.

RTP 35096v1 DETAILED DESCRIPTION OF THE INVENTION
For a more complete understanding of the present invention, reference should be made to the following detailed description taken in connection with the accompanying drawings, wherein like reference numerals designate corresponding parts throughout the several figures.
Referring first to Figs. 1 and 3, there is shown a schematic view of an embodiment of a process generally indicated at 8 for producing a mechanical and chemical embossed surface covering 10. In this embodiment, a web 19 is formed comprising a substrate 12, a curable wear layer 18, an expandable foam layer between the substrate 12 and the wear layer 18, and at least one inhibitor composition disposed as a pattern proximate the foam layer 14. The wear layer 18 is coated with a cross-linkable top coat 20 to form a coated web 21 and then heated to a temperature at which the top coat 20 is substantially cross-linked and cured, the wear layer 18 is substantially cured, the foam layer 14 expands to some extent, and the pattern is chemically embossed to form a surface covering 11. Thereafter, the surface covering 11 is tempered to a temperature above ambient temperature. The top coat 20 is then heated and at least one surface texture is mechanically embossed onto the top coat 20.
Upon setting the at least one surface texture, the mechanical and chemical embossed surface covering 10 is formed. In addition, mechanical embossing includes mechanical embossing in register with a printed or chemically embossed pattern of the surface covering 11.
As indicated in Fig. 1, the substrate 12 is removed from an appropriate unwind roll 22 and fed past a pinch roll structure 24, which is nothing more than the feed structure for pulling the substrate 12 off the unwind roll 22 and pushing it partly through the processing operation. The substrate 12 then passes through a dancer roll structure 26 which is conventional in the art and simply functions to take up slack in the feed of the substrate 12 and aids in tension control. Optionally, the substrate 12 can then pass around an appropriate guider structure (not shown), which maintains the registry of the substrate 12 in a direction transverse to the direction of substrate movement.

RTP 3509Gv 1 The expandable foam layer 14 comprises a resinous composition containing a chemical blowing agent and is applied to a surface of the substrate 12 to form a coated substrate 13. In one embodiment, the expandable foam layer 14 has a substantially uniform thickness. The expandable foam layer 14 is coated onto the substrate 12 by any suitable conventional coating apparatus 28 such as a reverse roll coater, a doctor blade, an air knife, or other similar coating apparatus. The coated substrate 13 is then passed through a heating unit generally indicated at 30 which supplies sufficient heat to at least partially gel the resinous coating, for example, a thermoplastic resinous coating, without decomposing the blowing agent. Any conventional heating unit such as a bank of radiant heaters, an oven, a heated drum, and the like may be utilized.
The gelled foam layer 14 and substrate 12 are then passed to a printing unit which places the print layer 16, which in one embodiment includes a printing ink composition, onto the jelled foam layer 14. Any conventional printing apparatus such as a silk screen apparatus, a flat bed printing machine, an ink jet printer, or a conventional gravure or rotogravure press which is etched to print a design with a suitable ink can be utilized to print on the surface of the gelled foam layer 14. The print layer 16 is conventionally dried in the printing unit 32. One or more of the printing ink compositions, which may be either pigmented or transparent, contain an inhibitor or an accelerator for the blowing agent in the foamable layer 14.
Further, concentrations of inhibitor or accelerator can differ from one printing ink composition to another. Accordingly, the print layer 16 can be printed wherein the printing ink and inhibitor or accelerator composition vary from one portion or area to another.
Alternatively or in addition to the inhibitor or accelerator present in the print layer 16, the inhibitor or accelerator can be printed or otherwise applied to the substrate 12 and then the foam layer 14 applied over the inhibitor or accelerator.
Accordingly, the inhibitor or accelerator composition can be a pigmented composition, for example, the aforementioned printing ink composition, which can be visible from the surface of the mechanical and chemical embossed surface covering 10. The pigmented composition is visible if substantially complete inhibition of the RTP 3509Gv1 blowing agent is obtained and the non-foam areas of the foam layer 14 and any subsequent layers disposed thereon are at least translucent or substantially clear.
The wear layer 18 comprises a coat of a resinous composition, such as a polyvinyl chloride plastisol or organosol, and is applied over the print or foam layers 16 and 14 by another conventional coating apparatus 28' such as to a reverse roll coater, a doctor blade, an air knife, or other similar coating apparatus.
Optionally, the wear layer can be applied by melt coating or film lamination techniques. In one embodiment, the wear layer 18 has a substantially uniform thickness across the coated substrate 13. The wear layer 18 can be transparent, translucent or pigmented opaque.
If the wear layer 18 is opaque, the inks will not be visible from the surface of the mechanical and chemical embossed surface covering 10. After applying the wear layer 18, the composite structure is passed through another heating unit 36 which supplies sufficient heat to at least partially gel the wear layer 18 without decomposing the blowing agent to form a web 19. Again, any conventional heating unit such as a bank of infra-red heating lamps, an oven, a heated drum, and the like may be utilized.
Thereafter, a print layer 16 can be optionally printed onto the jelled wear layer 18 in addition to or as an alternative to the print layer 16 on the foam layer 14.
However, for chemical embossing of the foam layer 14, an inhibitor and/or accelerator must be able to interact with the foam layer 14 for the areas in which non-foaming is desired.
As previously discussed, the foam and wear layers 14 and 18 are formed into a coating having the desired thickness and then heated to gel the composition to provide a suitable surface for application of the inhibitor, the print layer 16, and/or other layers or coatings. The term "gel" includes both the partial solvation to the elastomeric point of the resinous composition and complete solvation of the resin or resins with the plasticizer to fuse the layers and top coat. For example, the temperature is raised to between about 275° F and 325° F, in one embodiment, about 300° F, to gel the preferred polyvinyl chloride resinous compositions.
The top coat 20, also known as an extended wear layer, is applied over the jelled wear layer 18 to form the coated web 21. In one embodiment, the top coat 20 comprises a coat of a cross-linkable resinous composition, such as a cross-linkable RTP 35096v1 polyurethane, epoxies, melamines, and other cross-linkable resins.
Thermoplastic resins, such as thermoplastic polyurethane and acrylics can also be employed.
The top coat 20 is applied by another conventional coating apparatus 28" such as a reverse roll coater, a doctor blade, an air knife, or other similar coating apparatus to form a coated web. Similar to the wear layer 18, the top coat 20 can be transparent, translucent, or pigmented opaque and, in one embodiment, has a substantially uniform thickness across the wear layer 18. Again, if the top coat 20 is opaque, the inks will not be visible from the surface of the mechanical and chemical embossed surface covering 10.
The coated web 21 is then passed through a fusion oven 40 to fuse, cure, and expand the coated web 21, thereby forming a surface covering 11. The fusion oven 40 can be any heating apparatus such as a hot air impingement oven or infra-red heat lamps. In one embodiment, the fusion oven 40 heats both surfaces of the coated web 21. The fusion oven 40 raises the temperature of the resinous compositions on the substrate 12 sufficiently high to cause the selective decomposition of the blowing agent contained in the foam layer 14 and to completely solvate and fuse all resinous layers on the substrate 12. If the substrate 12 comprises a resinous composition, the substrate 12 is fused to an adjacent resinous layer, such as the foam layer 14. The cellular foam areas not in contact with or exposed to any inhibitor composition can reach their maximum expansion or blow. The portion of foam layer 14 in contact with any area or composition having a concentration of inhibitor will have little or no foam structure or expansion. However, as indicated above, those foam areas exposed to a portion of the print layer 16 having smaller concentrations of inhibitor can have more foam structure or expansion than those areas having a greater concentration of inhibitor.
Upon exiting the fusion oven 40, the surface covering 11 is tempered to at least a temperature where the surface 12 covering resists blistering or separation between the substrate and layers thereof upon application of an external stress, such as a mechanical embossing procedure. Tempering is accomplished in the present invention by temperature reduction of the surface covering. This is particularly RTP 35096v1 important since any premature handling of the surface covering 11 immediately after foaming might cause partial collapse and distortion of the foam structure.
Importantly, although permissible, it is not necessary to reduce the temperature of the surface covering 11 to ambient. In one embodiment, the temperature is reduced to between about 125 and 300° F for tempering the surface covering 11. In another embodiment, the tempering is performed at a temperature between about 240°F and 300° F. Because the surface covering 11 does not need to be reduced to ambient temperature, the process of the present invention reduces energy demands in any heating requirement following tempering, permits a continuous process which reduces handling requirements by the manufacturer, and reduces space requirements for either storage or process line length.
Tempering can be accomplished through various methods. For example, tempering can be accomplished by allowing the surface covering to sufficiently cool to the desired temperature through atmospheric radiant heat transfer as it moves along the process line prior to engaging any device following the fusion oven. A
blowing device (not shown), such as a fan or an air conditioning unit, may be employed to assist in this tempering technique. In one embodiment, a tempering unit 42 is utilized to temper the surface covering. Depending upon line speed, surface covering composition, and surface covering temperature exiting the fusion oven 40, a conventional back wetter 46 may be included with or utilized as an alternative to the tempering unit 42 for additional tempering of the surface covering 11. The back wetter 46 applies water to the substrate of the surface covering 11, which assists in cooling.
In the present invention, the tempering unit 42 comprises at least one surface cooled tempering roller 44 having a relatively smooth contact surface. In the preferred embodiment, the tempering unit 42 has two water-cooled, chrome-plated steel tempering rollers 44. As illustrated in Fig. 1, the tempering rollers 44 are positioned so that the surface covering 11 is fed through the tempering rollers in an "S" configuration and passes around and is maintained in contact with between from about 180° to about 200° of the circumference of each tempering roller 44 (about 180°
RTP 3509Gv1 to about 200° of wrap). In this configuration, the substrate 12 of the surface covering 11 initially contacts one tempering roller 44, and the other tempering roller contacts the top coat 20. To avoid incidental mechanical embossing of the top coat 20, the tempering roller 44 contacting the top coat 20 should have a surface roughness no greater than 32 microinch (10-b inch) root-mean squared (32 RMS). The surface smoothness of the tempering roller 44 contacting the substrate 12 is not as critical.
Clearly, the tempering rollers 44 can have any desired outside diameter, more than two tempering rollers 44 may be utilized, and the amount of wrap about the tempering rollers 44 can be more or less than that mentioned above.
Optionally, a breaking mechanism 48 is operably connected to the tempering rollers 44. By applying rotational resistance to the tempering rollers 44, the breaking mechanism 48 isolates the relatively high tension that is applied to the surface covering 11 during mechanical embossing from the respectively lower tension applied to the substrate 12 during the chemical embossing stage of the process. This is particularly useful when the substrate 12 has a hot melt calendered layer 6 disposed thereon, which is described below. The breaking mechanism 48, such as a motor, disc break, and the like, maintains a back tension on the surface covering 11 as it enters an embosser nip 52 and provides the ability to control the tension on the substrate 12 to prevent breakage or tearing while in the fusion oven 40.
Thereafter, the surface covering is heated by a high temperature heater 50 which rapidly heats the top coat 20, but does not heat the total surface covering 11 thickness to a uniform temperature. Importantly, the top coat 20 is heated to a sufficient degree to allow it to be mechanically embossed without fracture, cracking, or structural failure, such as de-lamination. That is, the top coat 20 is heated to a sufficient temperature for a sufficient time in order to soften or even further soften the top coat 20. The amount of heat to be applied and the duration of such application depends upon, among other things, the temperature of the surface covering 11 exiting the tempering unit 42, the composition of the top coat 20, the thickness of the top coat 20, the speed of the moving surface covering 11, the color of the printed design under the wear layer 18 surface, and the color of the resinous layers. For example, a cross-RTP 3509Gv1 linked polyurethane top coat 20 is heated to a temperature from about 250° F to about 350° F. To further enhance heating of the top coat 20, the resinous layers can comprise a resin or contain agents which absorb energy from a desired frequency of the infra-red spectrum.
For example, a surface covering 11 has a top coat 20 approximately 1 mil thick, a wear layer 18 approximately 10 mils thick, a foam layer 14 approximately 35 mils thick, and a substrate 12 approximately 30 mils thick. The temperature at the interface between the wear layer 18 and the foam layer 14 is only about 220° F. At the interface between the foam layer 14 and the substrate 12, the temperature is approximately 150° to 170° F. On the back side of the substrate 12 at the point farthest from the high temperature heater 50, the temperature is only about 150° F.
Optionally, the high temperature heater 50 may be a burner, such as a gas burner. One example is the "Blu-Surf ' burner sold by the Blu-Surf Division of I-ayes-Albion Corporation of Parma, Michigan. This is a burner structure which operates with a very short flame coming off an air-gas manifold. The hot gases from the flame are directed by a nozzle structure towards the top coat of the surface covering. The surface covering is moved at approximately 200 feet per minute past two heaters which are spaced approximately 12 inches from the top coat surface. The length of the enclosed heating area is only about 40 inches, and the heaters put out approximately 10,000-14,000 Btu's per square inch per hour. During the short time (approximately 1 second) that the surface covering 11 passes by the burners, the surface of the top coat 20 facing the burners is heated to about 320°
F. It is known that the above heating can be carried out at a temperature range of 250° F to 350° F.
for a time span of about 0.6 to about 6 seconds to secure the desired results.
In one embodiment, the high temperature heater SO comprises a bank of infra-red heaters. Suitable infra-red heaters are 10.1 kW RADPLANE SERIES 81 infra-red heaters manufactured by Glenro, Inc., Patterson, New Jersey. The high temperature heater 50 should extend beyond the respective edges of the surface covering 11 to assist in heating the portions of the top coat 20 proximate the edges. Top coat edge temperature and heating are further discussed below.

RTP 3509Gv1 From the high temperature heater 50, the surface covering moves directly to the embosser nip 52 which comprises a conventional engraved steel embossing roll 54 and a back-up roll 56. In one embodiment, the embossing roll 54 is water cooled and servo-driven, and the back-up roll is a steel back-up roll 56. Upon engaging the embosser nip 52, the steel back-up roll 56 contacts the substrate 12 and the embossing roll 54 contacts the hot top coat 20 of the surface covering 11. In the present invention, the embossing roll 54 is approximately 22.8 inches in outside diameter, and the back-up roll 56 is approximately 24 inches in outside diameter. If the back-up roll 56 is a rubber back-up roll, the rubber back-up roll can be provided with a steel support roll (not shown) to counteract any tendency of the rubber roll to "bow"
downward. In the present invention, the surface covering 11 wraps the embossing roll 54 between about 85° to about 90° by means of an articulatable idler roll 58.
However, the amount of wrap of the surface covering 11 on the embossing roll depends upon the temperature and the speed of the surface covering 11 through the embosser nip 52 and can be more or less than between about 85° to about 90°. Wrap should be sufficient to cool the mechanical and chemical embossed surface covering 11 to a temperature below about 250° F. In one embodiment, the embossing roll 54 has substantially the same temperature across its surface. This contact with the cooled embossing roll surface removes heat from the top coat 20 of the surface covering 11 by heat transfer from the surface covering 11 to the water-cooled, steel embossing roll 54, and thus "sets" the embossing to form the mechanical and chemical embossed surface covering 10. Dwell time of the surface covering on the embossing roll 54 is dependent on exact embossing roll circumference and line speed, which can be determined by one skilled in the art. The preferred line speed or rate of the surface covering 11 through the embosser nip 52 is between about 65 feet per minute to about 100 feet per minute.
The embosser nip 52 or gap can float against a fixed pressure or, in one embodiment, can be adjustably fixed. Adjustment to the embosser nip 52 can be made, for example, by adjustable steel wedge blocks (not shown) or, in one embodiment, by a jack screw (not shown). However, when the embosser nip 52 is RTP 350)Gvl fixed, consistent caliper of the surface covering 11 prior to entry into the mechanical embossing section of the process needs to be monitored and maintained. The preferred starting point of the fixed gap is between from about 0.010 inch to about 0.020 inch less than the specific product thickness or caliper. Fine-tuning adjustments thereafter are made to achieve the desired appearance. Furthermore, in order to maintain consistent reproduction of the embossing roll pattern in the top coat 20 of the surface covering 11, positive tension should be maintained on the surface coating 11 as it enters the embosser nip 52. This tension also helps to keep the surface coating tracking straight.
The mechanical embossing of the top coat 20 can be achieved in such a manner that the wear and foam layers 18 and 14 beneath the top coat 20 may or may not be mechanically embossed. Importantly, the portion of the foam layer 14 either overlayed or in contact with the inhibitor composition, for example, the print layer 16, is not mechanically embossed. And, the depth of the embossing into the portions or areas of the foam layer 14 beneath the areas or portions of the top coat 20 that are mechanically embossed is controlled by the pattern protruding from the embossing roll 54. For purposes of the present invention, in addition to the engraved steel embossing roll 54 and the steel back-up roll 56 discussed above, any mechanical embossing technique known to those skilled in the art can be used.
During mechanical embossing, the embossing roll 54 can, although not required, bottom out against the top coat surface. That is, not only the raised areas, but also the depressed areas of the embossed pattern on the embossing roll 54 substantially engage the top coat 20 of the surface covering 11. Consequently, both the raised and depressed areas of the embossing roll 54 can provide a pattern effect directly on the top coat 20 of the surface covering 11. By the time the now chemically and mechanically embossed surface covering 10 is able to leave the embossing roll 54, it has cooled to below about 240° F on the surface of the top coat 20. The mechanical and chemical embossed surface covering 10 is then optionally wrapped on a second cooled roll (not shown) for further cooling.

RTP 35096v1 As indicated above, the embossing roll 54 is a steel roll with the appropriate embossing pattern thereon. Further, the surface and pattern of the embossing roll 54 can be coated with a non-stick or friction reducing material, for example, a tetrafluoroethylene fluorocarbon polymer, a diamond-like carbon and silicon material, and the like. The embossing roll 54 is a cooled roll, and when in operation with the embossing pattern engaging the surface covering 11, it is operated at a surface temperature of about 140° F or below, in one embodiment at about 90° F. The embosser nip 52 can fixably range from zero to 250 plus mils during operation.
This distance is measured from the raised area of the embossing roll 54 to the surface of the back-up roll 56. Although not required, a gap setting can be used which bottoms out the embossing roll 54 onto the top coat 20. For purposes of mechanical embossing, generally, the pressure applied to the top coat 20 is sufficient to create an embossing of, for example, from about 4 mils to about 12 mils. Depending upon the desired visual effects of the mechanical embossing the embossing can be more or less than 4 mils to 12 mils depth. As indicated earlier, the chemical embossing portion is generally deeper than that of the portions of the surface covering 11 which have only been mechanically embossed. However, it is possible to mechanically emboss in register and provide mechanically embossed portions which are deeper than the chemically embossed portions. This process, which does not create the mechanically embossed surface texture in the deep, essentially unblown chemically embossed portion, although it could, imparts to the mechanical and chemical embossed surface covering 10 the appearance of mechanical embossing in register. If desired, the chemically embossed portion, the raised, non-chemically embossed portions and/or the pattern can be mechanically embossed in register with a different surface texture as well by using the patterned embossing roll 54.
The mechanical and chemical embossed surface covering 10 then passes to a tension control device 60, such as a dancer structure, a load cell roll, and the like, which maintains tension control in the process line, particularly the mechanical embossing section. At about this point, the mechanical and chemical embossed surface covering 10 has been cooled to approximately 75° F-100°
F (ambient RTP 35096v1 temperature). The mechanical and chemical embossed surface covering is then wound or rolled on an appropriate winding structure 62.
As indicated above, a critical feature of the invention is the surface temperature of the surface covering 11 as it enters the embosses nip 52. In addition to the factors mentioned above, this temperature is also dependent on the position where the measurement is taken. However, this position may not be readily accessible for temperature measurements because of the diameter of the embossing roll 54.
Normally, therefore, the reading is taken from the mid-point of the distance between the end of the high temperature heater 50 and the embosses nip 52. The actual temperature as the surface covering 11 enters the embosses nip 52 will be lower than this reading because of heat loss from the top coat 20 of the surface covering 11 as it moves through the space between the measurement point and the embosses nip 52.
The faster the line speed, the less opportunity for heat loss and the closer the actual temperature will be to the measured temperature at the embosses nip 52. It is desirable for the top surface 20 to have substantially the same temperature across the surface covering as the surface covering enters the embosses roll nip 52.
However, heat loss is greater along side edges of the surface covering 11. To compensate for this heat loss, portions of the top coat 20 along the side edges, for example, respective portions approximately 4 inches wide from either edge of the surface cooing, are subjected to further heating. This additional heating assists in maintaining a temperature profile across the top coat 20 that, at least in one embodiment, does not deviate more than about 5° F. As discussed above, the high temperature heater SO
extends beyond the respective edges of the surface covering 11 to provide thorough heating of these portions of the top coat 20.
It is certainly within the bounds of the present invention to use several devices to mechanically emboss different textures onto the top coat 20. Examples of patterns which can be mechanically embossed onto the surface covering 11 include patterns that simulate the surface texture of wood, stone, marble, granite, brick, tile, or any other desired covering material.

RTP 3509Gv1 Referring now to Figs. 2 and 4, there is shown a schematic view of another embodiment of a process generally indicated at 8', for producing a mechanical and chemical embossed surface covering 10'. This embodiment is substantially similar to the embodiment discussed above, except that the top coat 20, if present, is not mechanically embossed. Accordingly, the previous discussion of like components and apparatus are applicable to this embodiment. Here, the web 19 is formed comprising the substrate 12, the expandable foam layer 14 operably connected to the substrate 12, and at least one inhibitor composition disposed as a pattern proximate the foam layer 14. The foam layer 14 is coated with a wear layer 18 to form a coated web 21 and then heated to a temperature at which the wear layer 18 is substantially cured, the foam layer 14 substantially expands, and the pattern is chemically embossed to form a surface covering 11. Thereafter, the surface covering 11 is tempered to a temperature above ambient temperature. The wear layer 18 is then heated and at least one surface texture is mechanically embossed onto the wear layer 1 S 18. Upon setting the at least one surface texture, the mechanical and chemical embossed surface covering 10 is formed. As previously indicated, mechanical embossing includes mechanical embossing in register with a printed or chemically embossed pattern of the surface covering.
As indicated in Fig. 2, the substrate 12 is removed from an appropriate unwind roll 22 and fed past the pinch roll structure 24 to pull the substrate 12 off the unwind roll 22 and push it partly through the processing operation. The substrate 12 then passes through the dancer roll structure 26 to take up slack in the feed of the substrate 12 and aid in tension control. Optionally, the substrate 12 can then pass around the appropriate guider structure (not shown), which maintains the registry of the substrate in a direction transverse to the direction of substrate movement.
The expandable foam layer 14 comprises a resinous composition containing a chemical blowing agent and is applied to a surface of the substrate 12 to form the coated substrate 13. In one embodiment, the expandable foam layer 14 has a substantially uniform thickness. The expandable foam layer 14 is coated onto the substrate 12 by of the any conventional coating apparatus 28 previously discussed.

RTP 35096v 1 The coated substrate 13 is then passed through heating unit 30 which supplies sufficient heat to at least partially gel the resinous coating without decomposing the blowing agent. As discussed above, heating unit 30 may be utilized to jell the foam layer 14.
The gelled foam layer 14 and substrate 12 are then passed to the printing unit 32 which places the print layer 16, that in one embodiment includes a printing ink composition, onto the jelled foam layer 14. The print layer 16 is conventionally dried in the printing unit 32. One or more of the printing ink compositions, which may be either pigmented or transparent, contain the inhibitor or the accelerator for the blowing agent in the foamable layer 14. Further, concentrations of inhibitor or accelerator can differ from one printing ink composition to another.
Accordingly, the print layer 16 can be printed wherein the printing ink and inhibitor or accelerator composition vary from one portion or area to another.
As before, the inhibitor or the accelerator can be printed or otherwise applied to the substrate 12, and then the foam layer 14 applied over the inhibitor or the accelerator alternatively or in addition to the inhibitor or accelerator present in the print layer 16. Accordingly, the inhibitor or accelerator composition can be a pigmented composition, for example, the aforementioned printing ink composition, which can be visible from the surface of the mechanical and chemical embossed surface covering 10. The pigmented composition is visible if substantially complete inhibition of the blowing agent is obtained and the non-foam areas of the foam layer 14 and any subsequent layers disposed thereon are at least translucent or substantially clear.
The wear layer 18, which comprises a coat of a resinous composition, such as a polyvinyl chloride plastisol or organosol, is applied over the print layer 16 by any conventional coating apparatus 28 previously discussed to form the web 19. In one embodiment, the wear layer 18 has a substantially uniform thickness across the coated substrate 13. The wear layer 18 can be transparent, translucent or pigmented opaque.
If the wear layer 18 is opaque, the inks will not be visible from the surface of the mechanical and chemical embossed surface covering 10.

RTP 3509Gv1 After applying the wear layer 18, the web 19 is passed through the fusion oven 40, which is discussed above, to fuse, cure, and expand the web 19 and form the surface covering 11. In one embodiment, the fusion oven 40 heats both surfaces of the web 19. The fusion oven 40 raises the temperature of the resinous compositions on S the substrate 12 sufficiently high to cause the selective decomposition of the blowing agent contained in the foam layer 14 and to completely solvate and fuse all resinous layers, including the substrate if comprising a resinous composition, on the substrate.
The cellular foam areas not in contact with or exposed to any inhibitor composition can reach their maximum expansion or blow. The portion of foam layer 14 in contact with or exposed to any area or composition having a concentration of inhibitor will have little or no foam structure or expansion. However, as indicated above, those foam areas exposed to a portion of the print layer 16 having smaller concentrations of inhibitor can have more foam structure or expansion than those areas having a greater concentration of inhibitor.
Upon exiting the fusion oven 40, the surface covering 11 is tempered to at least a temperature where the surface covering resists blistering or separation between the substrate 12 and layers thereof upon application of an external stress.
Again, tempering is accomplished in the present invention by temperature reduction of the surface covering 11. However, although permissible, it is not necessary to reduce the temperature of the surface covering 11 to ambient. In one embodiment, the temperature is reduced to between about 125° F to 300° F for tempering the surface covering 11. In another embodiment, the tempering is performed at a temperature between about 240° F to 300° F.
Tempering can be accomplished through the various methods previously discussed. In one embodiment, the tempering unit 42 is utilized to temper the surface covering 11. As before, the conventional back wetter 46 may be included with or substituted for the tempering unit 42.
Again, the tempering unit 42 comprises at least one surface cooled tempering roller 44 having a relatively smooth contact surface. In the preferred embodiment, the tempering unit 42 has two water-cooled, chrome-plated steel tempering rollers 44. As RTP 35096v1 illustrated in Fig. 2, the tempering rollers 44 are positioned so that the surface covering 11 is fed through the tempering rollers 44 in an "S" configuration and passes around and maintains a wrap from about 180° to about 200°. In this embodiment, the substrate 12 initially contacts one tempering roller 44, and the other tempering roller 44 contacts the wear layer 18. To avoid incidental mechanical embossing, the tempering roller 44 contacting the wear layer 18 should have a surface roughness no greater than 32 microinch (10-6 inch) root-mean squared (32 RMS). The surface smoothness of the tempering roller 44 contacting the substrate 12 is not as critical.
Clearly, the tempering rollers 44 can have any desired outside diameter, more than two tempering rollers 44 may be utilized, and the amount of wrap about the tempering rollers 44 can be more or less than that mentioned above. As previously indicated, the breaking mechanism 48 may optionally be operably connected to the tempering rollers 44 to maintain a back tension on the surface covering 11 as it enters the embosser nip 52. Again, the breaking mechanism 48 isolates the relatively high tension associated with mechanical embossing from the respectively lower tension associated with chemical embossing. This is particularly useful when the substrate 12 is the hot melt calendered substrate.
Thereafter, the surface covering 12 is heated by the previously described high temperature heater 50 to rapidly heat the wear layer 18. Importantly, the total surface covering thickness is not heated to a uniform temperature. The wear layer 18 is heated to a sufficient degree to allow it to be mechanically embossed without fracture, cracking, or structural failure, such as de-lamination. In one embodiment, the wear layer 18 is heated to a sufficient temperature for a sufficient time in order to soften or even further soften the wear layer 18. If the wear layer 18 is a thermoplastic resinous composition, it should be heated to at least the glass transition temperature.
Again, the amount of heat to be applied and the duration of such application depends upon, among other things, the temperature of the surface covering 11 exiting the tempering rollers 44, the composition of the wear layer 18, the thickness of the wear layer 18, the speed of the moving surface covering 11, the color of the printed design under the wear layer 18 surface, and the color of the resinous layers. To further enhance heating RTP 35096v1 of the wear layer 18, the resinous layers can comprise a resin or contain agents which absorb energy from a desired frequency of the infra-red spectrum.
From the high temperature heater 50, the surface covering 11 moves directly to the embosser nip 52. As previously discussed, the embosser nip 52 can float against a fixed pressure or, in one embodiment, can be adjustably fixed.
Again, the embossing roll 44 can be water cooled and servo-driven. In one embodiment, the back-up roll 46 is a steel back-up roll, however, in other embodiments, other back-up rolls, such as rubber back-up rolls, may be used. Upon engaging the embosser nip 52, the steel back-up roll 46 contacts the substrate 12 and the embossing roll 44 contacts the hot wear layer 18. In one embodiment, the embossing roll 44 is approximately 22.8 inches in outside diameter, and the back-up roll 46 is approximately 24 inches in outside diameter. Embossing and back-up rolls 44 and 46 having outside diameters larger or smaller may also be employed. The preferred wrap on the embossing roll 44 is between about 85° to about 90° and can be accomplished by articulatable idler roll 58. Wrap should be sufficient to set the embossing on the wear layer 18. In one embodiment, the mechanical and chemical embossed surface covering 10 is cooled to a temperature below about 250° F. Again, the embossing roll 44 should have substantially the same temperature across its surface. Again, dwell time of the surface covering 11 on the embossing roll 44is dependent on exact embossing roll circumference and line speed, which can be determined by one skilled in the art.
Furthermore, in order to maintain consistent reproduction of the embossing roll pattern in the wear layer 18, positive tension should be maintained on the surface coating 11 as it enters the embosser nip 52. This tension also helps to keep the surface coating 11 tracking straight.
The mechanical embossing of the wear layer 18 can be achieved in such a manner that the foam layer 14 beneath the wear layer 18 may or may not be mechanically embossed. Importantly, the portion of the foam layer 14 either in contact with or exposed to the inhibitor or the accelerator composition, for example, the print layer 16, is not mechanically embossed. And, the depth of the embossing into the portions or areas of the foam layer 14 beneath the areas or portions of the RTP 35096v1 wear layer 18 that are mechanically embossed is controlled by the pattern protruding from the embossing roll 44. For purposes of the present invention, in addition to the engraved steel embossing roll 44 and the steel back-up roll 46 discussed above, any mechanical embossing technique known to those skilled in the art can be used.
As with the embodiment discussed above, the embossing roll 54 can substantially bottom out against the wear layer surface during mechanical embossing.
By the time the now chemically and mechanically embossed surface covering is able to leave the embossing roll, it has cooled to below about 240° F on the surface of the wear layer. The mechanical and chemical embossed surface covering is then optionally wrapped on a second cooled roll for further cooling.
As indicated above, the embossing roll is a steel roll 44 with the appropriate embossing pattern thereon. It has been discovered, however, it is difficult to slip the wear layer 18 on the embossing roll 44, which is important for mechanical embossing in register. To assist in slipping the surface covering 11 of this embodiment, the surface and pattern of the embossing roll 44 can be coated with a non-stick or friction reducing material, for example, a tetrafluoroethylene fluorocarbon polymer, a diamond-like carbon and silicon material, and the like. The embossing roll 44 is a cooled roll, and when in operation with the embossing pattern engaging the surface covering 11, it is operated at a surface temperature of about 140° F or below, in one embodiment at about 90° F. The embosser nip 52 can fixably range from zero to 250 plus mils during operation. This distance is measured from the raised area of the embossing roll 54 to the surface of the back-up roll 56. In one embodiment, a gap setting is used which bottoms out the embossing roll 54 onto the wear layer.
As indicated earlier, the chemical embossing portion is generally deeper than that of the portions of the surface covering 11 which have only been mechanically embossed. It is possible for the mechanically embossed portion to be deeper than that of the portions of the surface covering 11 which are chemically embossed. This process, which does not create the mechanically embossed surface texture in the deep, essentially unblown chemically embossed portion, although it could, imparts to the mechanical and chemical embossed surface covering 10 the appearance of mechanical RTP 3509Gv1 embossing in register. If desired, the chemically embossed portion or pattern can be mechanically embossed in register with a different surface texture as well by using the patterned embossing roll 54.
The mechanical and chemical embossed surface covering 10 then passes to the tension control device 60, discussed above, which maintains tension control in the process line, particularly the mechanical embossing section. At about this point, the mechanical and chemical embossed surface covering 10 has been cooled to approximately ambient temperature. The mechanical and chemical embossed surface covering 10 is then wound or rolled on an appropriate rewind structure 62.
As indicated above, a critical feature of the invention is the surface temperature of the surface covering 11 as it enters the embosser nip 52, and the discussion above is likewise applicable. Again, for convenience, the temperature reading is normally taken from the mid-point of the distance between the end of the high temperature heater 50 and the embosser nip 52. The actual temperature as the 1 S surface covering 11 enters the embosser nip 52 will be lower than this reading because of heat loss from the wear layer 18 of the surface covering 11 as it moves through the space between the measurement point and the embosser nip 52. It is desirable for the wear layer 18 to have substantially the same temperature across the surface covering 11 as the surface covering enters the embosser nip 52. As discussed above, the high temperature heater SO extends beyond the respective edges of the surface covering 11 to provide thorough heating of these side edges of the wear layer 18 so that the temperature profile across the wear layer 18 does not deviate more than about 5°F.
It is certainly within the bounds of the present invention to use several devices to mechanically emboss different textures onto the wear layer 18. Examples of patterns which can be mechanically embossed onto the surface covering include patterns that simulate the surface texture of wood, stone, marble, granite, brick, tile, or any other desired covering material.
It is also possible to mechanically emboss in register (MEIR) the surface covering 11 produced by either embodiment of the process 8 and 8' of the present invention. That is, the surface covering 11 can be mechanically embossed in register RTP 35096v1 whether or not the top coat 20 is present. Mechanical embossing in register imparts surface textures that vary from one area to another. For example, one area of the top coat 20 or the wear layer 18 over the expanded foam layer 14 can be mechanically embossed with one surface texture while an adjacent area is embossed with another S surface texture. It is also possible to mechanically emboss more than two surface textures in register to the surface covering 11. Further, such variations in surface texture can be mechanically embossed in register with the printed pattern of the print layer 16. One option is to emboss different textures to two or more up areas of the printed design. For example, if the design is composed of tiles or stones with grout surrounds, the faces of different tiles/stones can be mechanically embossed with different textures. Another option is to mechanically emboss the chemically embossed grout areas to impart a texture different from the texture embossed on the tile/stones. The MEIR embossing capability allows for maximum design flexibility because it allows selective texturing of chemically embossed and non-chemically 1 S embossed regions.
To mechanically emboss in register, it is necessary to provide transverse guiding of the surface covering as it enters the embossing nip. Transverse guiding can be conducted with a structure as simple as a guide edge (not shown) or a "Kamberoller" which is a commercially available structure involving an angled guide roll on a carriage mounted for transverse movement. The Kamberoller can form a part of the tempering unit 42. Registry along the machine direction (MD) or in the direction longitudinally of the surface covering movement can be maintained in the same manner as set forth in U.S. Patent No. 3,655,312 to Erb et al., column 5, line 53, to column 6, line 43. The technique of U.S. Patent No. 3,694,634 can be adopted herein for machine direction registry. Both U.S. Patent Nos. 3,655,312 and 3,694,634 are incorporated herein in their entirety.
Registry can also be maintained with a servo controller 64 which phase shifts the embossing roll 54 by periodic rotational speed increase or decrease with nominal effect on the surface covering 11 speed. Typically, such phase shift occurs upon each complete revolution of the embossing roll 54. Contemporaneously, the servo RTP 35096v1 controller 64 matches the embossing roll 54 rotational speed with the average process speed of the surface covering 11 through the embosser nip 52. Phase shift realigns the embossing pattern on the embossing roll 54 with the printed pattern of the print layer 16 by slipping the surface covering 11 on the embossing roll 54. In one embodiment, the servo controller 64 is a positional control servo which self rotates the embossing roll 54. Such a servo is manufactured by Allen-Bradley (Milwaukee, WI) and referred to as a 1394 DRIVE SYSTEM. An alternative to the positional control servo for controlling the embossing roll 54 rotation is a combination of a Model R-S00 Digital Control (provides phase shift) (not shown) and a Model R-425-1 Feathering Drive Control System (provides speed matching) (not shown) of Registron Division of Bobst Champlain, Inc.
Mechanical embossing in register with the printed pattern of the print layer can be maintained as long as the surface covering 11 is capable of being slipped or stretched on the embossing roll 54 without fading, which is insufficient setting of the 1 S mechanically embossed pattern on the top coat 20 or the wear layer 18.
That is, the rate of movement of the surface covering 11 through the embosser nip 52 either in across machine, machine, and/or longitudinal direction is temporarily different with respect to the rotation rate of the embossing roll 54, whereby the surface covering 11 slips on the surface of the embossing roll 54. Yet, sufficient wrap must be maintained to set the embossed pattern during the slip adjustment to avoid fade. If the surface covering 11 can not be slipped, it can tear as register adjustments with the embossing roller 54 are made. It has been discovered that the cured top coat 20, although in a softened state as it enters the embossed nip 52, is sufficiently "slick" or has a coefficient of friction sufficiently low to allow slip as the aforementioned adjustments are made. As indicated above the embossing roll 54 can be coated with a friction reducing coating to enhance the slipping of the surface covering on the embossing roll 54, which is useful with thermoplastic resinous coatings. Accordingly, the mechanical and chemical embossed surface covering 10 can be slipped during mechanical embossing to produce in register surface textures.
RTP 35096v1 MD or phase register can also be maintained by stretching the surface covering 11 as it enters the embosser nip 52, if the composition of the surface covering permits stretching without structural failure thereof. Stretching occurs by holding a back tension on the surface covering 11 as it enters the embosser nip 52. Back tension can be maintained by the breaking mechanism operably connected to the tempering unit.
Skew register can be maintained by adjusting the angle at which the surface covering enters the embosser nip 52. In the present invention, this is accomplished by squaring the tempering unit 42 with the production line. That is, the tempering unit 42 is positioned substantially perpendicular to the direction of surface covering 11 movement. The back wetter 46 comprises a roll 46 which is pivotally mounted so that it is capable of pivoting with respect to the embosser nip 52. A proximal end of the back wetter roller 46 is pivotally mounted to a mount (not shown) so that its distal end moves forwardly or rearwardly along an arc. In one embodiment, the surface covering 11 has a wrap between about 40° to about 90° wrap, in one embodiment, about 80°, on the back wetter roll 46. As the back wetter 46 is pivoted in an appropriate direction, the surface covering 11 entry angle or skew realigns so that the surface covering enters the embosser nip 52 substantially parallel to the embosser roll 54.
Across machine direction (AMD) register is be maintained by moving the surface covering 11 with respect to the embosser nip 52 from one side of the embossing roll 54 toward the other side until the embossing pattern appropriately aligns with the printed pattern along the surface covering edges. Although this can be accomplished by laterally moving the surface covering 11 with respect to a stationary embossing roll 54, it is preferred to laterally shift and slip the embossing roll 54 with respect to the moving surface covering 11. The embossing roll 54 is rotatably mounted to a frame 66 which is laterally movable with respect to the surface covering 11. The back-up roll 56, however, remains stationary with respect to lateral movement. To adjust AMD register, the embossing roll 54 is moved laterally in the appropriate direction to align the embossing pattern with the printed pattern on the surface covering 11.

RTP 3509Gv1 Further, it is important during any slipping operation to maintain constant and sufficient tension on the surface covering 11 as it feeds into the embosser nip 52.
Absent constant and sufficient tension, the surface covering 11 is unlikely to properly slip, if at all, resulting in damage to the surface covering. For example, if too much tension is placed on the surface covering 11 and the rotation rate of the embossing roll 54 is increased, the surface covering 11 can tear. On the other hand, if too little tension is maintained on the surface covering 11 and the rotation rate of the embossing roll 54 is decreased, wrinkles or other similar defects can appear in the surface covering 11. Tension is maintained on the surface covering 11 by the tension control device 60 mentioned above. The appropriate amount of tension to be applied to the surface covering 11 is dependent upon surface covering temperature and composition, particularly the top coat 20, if present, or the wear layer 18 composition, the embosser nip 52 gap and pressure, embosser roll 54 wrap, and overall tension on the surface covering 11 throughout the process, among other things. Thus, the 1 S appropriate amount of tension is generally specific for the mechanical and chemical embossed surface covering 10 being then produced and must be determined by "fine tuning" the process.
As a result of passing the surface covering 11 through the embodiments of the process of the present invention, there is formed a mechanical and chemical embossed surface covering 10 with a cross section such as that respectfully shown in Figs. 3 and 4. Refernng to Fig. 3, one embodiment of the mechanical and chemical embossed surface covering 10 comprises the substrate 12, an optional hot melt calendered layer 6, the chemically embossed foam layer 14, the print layer 16, the wear layer 18, and the mechanically embossed top coat 20. Referring to Fig. 4, another embodiment of the mechanical and chemical embossed surface covering 10 comprises the substrate 12, an optional hot melt calendered layer 6, the chemically embossed foam layer 14, the print layer 16, and the mechanically embossed wear layer 18. Now referring to Fig. 5, another embodiment of the mechanical and chemical embossed surface covering 10 comprises the substrate 12, an optional hot melt calendered layer 6, the chemically embossed foam layer 14, the print layer 16, and the mechanically RTP 35096v1 embossed wear layer 18, where the mechanical embossing extends into the chemically embossed area 70. With reference to both Figs 3-5, the chemically embossed pattern 70 is deeply embossed. Embossed region 72, located on one side of the chemically embossed pattern 70, is similarly deeply embossed, however, region 72 is mechanically embossed. Likewise, embossed region 74, which is disposed on the other side of the chemically embossed pattern is mechanically embossed, but not as deep as region 72. Although the top coat 20, as shown in Fig. 3, and the wear layer, as shown in Fig. 4, has been depressed in region 72 below the normal plane of the respective coat or layer surface, the foam layer 14 retains its cellular structure and the respective coat or layer 18 or 20 retains substantially the same thickness as the respective non-embossed coat or layer. However, the cell structure has been somewhat compressed and reduced in size. The substrate 12 and the hot melt calendered layer 6 appear to be unaffected by the embossing operation. Should this particular mechanical and chemical embossed surface covering 10 be heated again, the 1 S stress in the respective coat or layer 18 or 20 as a result of the mechanical embossing may or may not be relieved, depending upon the resinous composition selected for the respective coat or layer 18 or 20. The foam cells may have sufficient resiliency to cause the mechanical embossing to relax. That is, heating of the foam material could possibly cause the depressed areas created by mechanically embossing to raise back to their normal position, and consequently, the resulting mechanical and chemical embossed surface covering 10 could appear only as a chemically embossed surface covering. This is a clear indication that the foam material under the mechanically embossed regions can have the foam regions unaffected or virtually undamaged by the embossing operation. Consequently, these regions retain a substantial degree of resiliency. Because the embossing nip 52 gap is adjustable, it is possible to mechanically emboss in register with the printed pattern of the print layer 16 and provide multiple surface textures to the raised areas which coincide with such printed pattern. As indicated in Figs. 3 and 4, it is possible to mechanically emboss one region, for example, region 72, with a surface texture having a visual effect and another region, for example, region 74, with a respectively different surface texture, RTP 35096v 1 thereby creating a distinctively different surface texture. Also, a matte finish and/or other minute texture can be applied to portions of the chemically embossed pattern 70.
As shown in Fig. 5, it is possible to emboss the bottom of the chemically embossed section. The mechanical embossing overlying the chemically embossed areas can be performed, for example, with an embossing roll with grout texture, tile texture and/or stone texture. Such mechanical embossing will provide the chemically embossed areas with grout, tile and/or stone texture.
The combination of chemical embossing and mechanical embossing in register permits the formation of designs such as grout lines without having to crush selected expanded foam areas. Crushing selected areas, in contrast to mechanically embossing chemically embossed areas, displaces air from the foam and creates "blisters"
in the final product. Accordingly, the combination of chemical and mechanical embossing improves yields of acceptable products.
In the present invention, for purposes of creating the chemically embossed foam layer, the web 19 comprises a substrate 12 and the expandable and resinous foam layer 14 containing a foaming or blowing agent. The print layer 16, which can form a printed pattern design, is provided over at least a portion of the expandable foam layer 14. A plurality of print layers 14 can be disposed on the substrate 12, the foam layer 14 and/or the wear layer 18. The print layer 16 can comprise an inhibitor or an accelerator composition. Additionally, the inhibitor or the accelerator composition can be printed onto or proximate the foam layer 14 to provide a chemically embossed pattern. As described above, once the wear layer 18 and the top coat 20 are applied on top of the foam layer 14, the expandable foam layer 14 is then subjected to a sufficient temperature for a sufficient time to expand such layer. As a result, the chemically embossed region or pattern proximate the portion of the printed design containing the foaming or blowing agent inhibitor or accelerator is formed.
Generally, a sufficient temperature is from about 350° F to about 400° F and for a time of from about 0.8 minute to about 3 minutes to expand the foam layer 14.
It should be understood, however, that the inhibitor or the accelerator can be applied at RTP 35096v1 random rather than as an exact reproducible design. Further, it is not required for the ' inhibitor or the accelerator to be directly applied to the expandable foam layer 14.
The substrate 12 of the present invention can be any conventional substrate, earner, or backing layer used in surface coverings. Its selection depends in large measure on the product to be produced. For example, in one embodiment of the invention, the substrate 12 remains as a part of the mechanical and chemical embossed surface covering 10. Accordingly, the substrate 12 can be formed of a resinous composition, a woven, knitted, or non-woven fabric, a paper product, a felted or matted fibrous sheet of overlapping, intertwined natural, synthetic, or man-made cellulosic filaments and/or fibers, and other forms of sheets, films, textile materials, fabrics, and the like. In addition, any thermoplastic or elastomeric resinous composition which can be formed into a sheet may be utilized as the substrate 12.
These resins typically can be compounded with plasticizers and fillers and sheeted to form a substrate. Such resins include, but are not limited to, butadiene-styrene copolymers, polymerized chloroprene, and the like. Also, the substrate 12 can be a non-foamed, non-crosslinked vinyl composition such as polyvinyl chloride, polyvinyl acetate, and vinyl chloride-vinyl acetate copolymers. Additional substrates 12 useful with the present invention are also discussed in U.S. Patent No.3,293,108 to Nairn et al., which is incorporated herein in its entirety. The thickness of the substrate 12 is generally not critical and it is from about 5 to about 150 mils. In one embodiment, the thickness is from about 10 mils to about 80 mils.
The substrate 12 can be further coated with the hot melt calendered ("HMC") layer 6 manufactured by a HMC process. HMC refers to the process of formulating a homogeneous mixture containing a hot melt processable resin and, in various embodiments, plasticizer, stabilizer, filler, and/or other ingredients, heating the mixture, and delivering the heated mixture to a calender where the mixture is applied in a precisely controlled thickness to the substrate 12 to form a laminated substrate.
Although the substrates 12 mentioned above are suited for the HMC process, the preferred substrates 12 are felt or polyester sheet. Such melt processable resins include, but are not limited to, polyvinyl chloride (including general purpose RTP 35096v1 polyvinyl chloride as defined in ASTM Standard D1755-92), polyethylene, polypropylene, polystyrene, and copolymers thereof. The HMC layer should comprise less than 30 percent by weight of plasticizer, in one embodiment, less than percent by weight. Fillers can include mineral fillers, such as clay, talc, dolomite, S and limestone, and in some embodiments comprise at least about 60 percent by weight of the HMC layer.
The constituents of the HMC layer 6 are mixed in a mixer (not shown), and fed into a calender (not shown) at a desired mix temperature. The calender nip (not shown) opening of the calender is adjusted to the desired thickness of HMC
layer 6 10 and the HMC layer 6 is melt-coated directly onto the substrate 12 by bringing the substrate 12 into contact with a calender transfer roll (not shown) in a continuous process to form a laminated HMC substrate. The HMC substrate can also be produced by bringing the HMC layer 6 into contact with the heated substrate 12 downstream from the calender.
In one embodiment, the foam layer 14 is applied to a substrate 12 and gelled as described above. The constituents of the HMC layer 6 are processed in a high intensity mixer (not shown). The HMC layer 6 is calendered to the desired thickness, brought into contact with one side of the substrate 12, and coated thereon to form a HMC substrate. Thereafter, the foam layer 14, an inhibitor or an accelerator composition, which can be disposed within a print layer 16, the wear layer 18, and top coat 20, if desired, can be coated onto either the HMC layer 6 or the exposed substrate 12 as previously described. Thus, the substrate 12 can either be exposed or an internal structure not visible to the customer.
If the backing is to be removable, the substrate 12 can be, for example, a release paper. Such paper conventionally has a coating on its surface to allow the plastic sheet to be easily stripped from the paper. Typical coatings used are clays, silicone compositions, polyvinyl alcohol, and similar compositions known in the art.
The foam layer 14 of the present invention can be any conventional foam layer used in surface coverings, such as a foam layer used in flooring. In particular, the foam layer 14 can be any suitable material known in the art for producing foam layers RTP 35096v1 such as a fluid or semi-fluid plastisol or organosol composition. Generally, the composition of the foam layer 14 is (i) a plastisol or organosol composition of a homopolymer of polyvinyl chloride, or a copolymer of polyvinyl chloride and one or more other co-polymerizable resins such as vinyl acetate, vinyl propionate, vinyl butyrate, vinylidene chloride, alkyl acrylates and alkyl methacrylates, a graft polymer of polyvinyl chloride and one or more other co-polymerizable resins, or blends thereof, or (ii) melt-processable resins that include a polyvinyl chloride, a polyamide, a polyester, a polyolefin, a polystyrene, a polyacrylic homo- or copolymer, or blends thereof. These and other such materials may be used to form the foam layer 14 of the present invention. Additionally, a cross-linked resin system may be employed as long as such resin system can be chemically embossed and cured.
In one embodiment, the foam layer 14 is a resilient, cellular foam layer formed from a resinous composition containing a foaming or blowing agent that causes the composition to expand on heating. It is also known in the art that foamable, resinous sheet material can be selectively embossed by controlling the decomposition temperature of a catalyzed blowing or foaming agent in the heat-expandable composition. For example, by applying a reactive chemical compound referred to in the art as an inhibitor, regulator, retarder, or accelerator to the heat-expandable composition, it is possible to modify the decomposition temperature of the catalyzed foaming or blowing agent in the area of application of the reactive compound.
It is thus possible to produce sheet materials having surface areas that are depressed with inhibitor application and raised proximate the area without inhibitor application.
In one embodiment, the foam layer 14 is applied as a coating to the substrate 12. In other embodiments, the foam layer 14 is applied as a preformed sheet or the composition is molded, extruded, calendered, or otherwise formed into any desired shape depending on the ultimate use of the product.
As indicated above, the expandable resinous composition comprising the foam layer 14 includes an effective amount of a foaming or blowing agent. The larger the amount of blowing agent within practical limits used, the greater is the expansion of the foam. Foaming or blowing agents are well known in the art and the particular RTP 35096v1 blowing agent selected usually depends on such matters as cost, resin, and desired foam density. Complex organic compounds which, when heated, decompose to yield an inert gas and have residues which are compatible with the resin are preferred as foaming or blowing agents. Such materials should have the property of S decomposition over a narrow temperature range which is particularly desirable to obtain a good foam structure. Examples of typical foaming or blowing agents include without limitation substituted nitroso compounds substituted hydrazides, substituted azo compounds, acid azides, and guanyl compounds, to name only a few. Foaming or blowing agents for use in the present invention must be decomposed an effective amount at a temperature below the decomposition temperature of the resinous compositions and substrate of the mechanically and chemically embossed surface covering. The preferred foaming or blowing agents are those that decompose above the elastomeric point of the resin composition of the foam layer 14 since this enables at least partial gelling of the foam layer 14 so that a design can be printed on its surface. Additionally, accelerators or catalysts can be added to the resinous composition of the foam layer 14 to accelerate the decomposition of the blowing agents, reduce the decomposition temperature, act as stabilizers for the resinous composition, and/or narrow the decomposition temperature range. Such accelerators and catalysts are known in the art. Further discussion of foaming or blowing agents is provided in U.S. Patent No. 3,293,108, column 11, line 37-column 12, line 24.
Further, the resinous composition can include solvents, viscosity modifiers, color and UV stabilizers, and the like.
The inhibitor can be conveniently incorporated in an inhibitor composition, in one embodiment incorporated in the printing ink composition to form a foam-retarding, printing ink composition, which is printed over the heat-expandable resinous composition. Such compositions are well-known in the art and are generally based on an organic solvent carrier or vehicle system. Foaming or blowing agent inhibitors or modifiers include but are not limited to tolyltriazole, benzotriazole, fumaric acid, malic acid, hydroquinone, dodecanethiol, succinic anhydride, and adipic acid. Examples of printing ink compositions useful with the present invention are RTP 35096v1 described in U.S. Patent No. 5,169,435 to Sherman et al., U.S. Patent Nos.
4,191,581 and 4,083,907 to Hamilton, U.S. Patent No. 4,407,882 to Houser, and U.S.
Patent No.
5,336,693 to Frisch. Further discussion of inhibitors is also provided in U.S.
Patent No. 3,293,108 to Nairn et al., column 14, line 38-column 17, line 47.
The print layer 16 is formed from the printing ink composition. As indicated above, the printing ink composition may or may not include at least one inhibitor or accelerator composition. The area or portions of the print layer comprising the printing ink composition without inhibitor will not inhibit expansion of the foam layer. Printing ink compositions usually comprise resins, plasticizers, solvents, pigments, stabilizers, dyes, accelerators, promoters, kickers, and the like.
They are applied by the conventional printing apparatus discussed above and are usually very thin, only a fraction of a mil. To inhibit or promote expansion of the foam layer, the blow or foam modifying agents, such as inhibitors, regulators, retarders, suppressants, accelerators, and the like, are added to the printing ink composition. Drying is usually 1 S conducted within the printing unit 32 and can be accomplished by exposure to air or by conventional heating and drying procedures. An example of such an ink composition contains an acrylic resin, water, alcohol, and one or more pigments.
In forming a design having both an inhibitor composition and one not containing a inhibitor composition, such a design can be done in register using multiple station rotogravure printing, as described in U.S. Patent No.
3,293,108. For example, the print layer 16 can form a pattern of joint or grout lines which are created with at least one inhibitor composition. Upon expansion of the foam layer 14, these portions will be chemically embossed and will visually form joint or grout lines to simulate such lines which exist with natural wood, stone, marble, granite, brick, or tile surfaces. The joint or grout lines created with the inhibitor composition generally will have a width of, for example, from about 0.125 inch to about 0.25 inch.
The wear layer 18 is usually a clear, unpigmented resinous composition, which provides the mechanical and chemical embossed surface covering 10 improved wearing or in-use qualities. Any suitable material known in the art for producing such wear layers 18 can be utilized with the present invention. The fluid or semi-fluid RTP 3509Gv1 thermoplastic and thermoset plastisol or organosol compositions utilized to form the foam layer 14 may likewise be utilized to form the wear layer 18. However, the wear layer 18 does not include the blowing or foaming agents. In one embodiment, the wear layer 18 is a polyvinyl chloride plastisol composition. The dry film thickness of the wear layer 18 is not critical. In one embodiment, the thickness is from about 5 mils to about 30 mils, and in another embodiment, from about 10 mils to about mils.
As indicated, the wear layer 18 may be applied to and adhered to either the foam layer 14 or the print layer 16. The wear layer 18 can be applied by any conventional coating apparatus 28 known in the art, such as a reverse-roll coater, an air knife coater, knife coater, and any other coater known in the art. Once the wear layer 18 is applied, the wear layer 18 is jelled. Jelling can be accomplished by subjecting the wear layerl8 along with the foam layer 14 and substrate 12 to a sufficient temperature, for example, by heating, to jell the wear layer 18. If the mechanical and chemical embossed surface covering 10 being produced does not include the top coat 20, the foam layer 14 can be expanded and cured and the wear layer cured by the fusion oven 40, as discussed above.
Optionally, besides the layers discussed above, one or more additional layers can be present, such as the layers described in U.S. Pat. No. 5,458,953, incorporated herein in its entirety by reference. Such additional layers include strengthening layers, additional foamable layers, and a wear layer base coat. The composition of these layers and their locations are described in U.S. Pat. No. 5,458,953 and can be used in the mechanical and chemical embossed surface covering of the present invention.
The top coat 20, if present, is deposited or applied on top of the wear layer to form the coated web 21. The coated web 21 is then subjected to heat or curing which cures the top coat 20 and wear layer 18, expands and chemically embosses the foam layer, and fuses all resinous layers to one another, as described earlier. For purposes of curing the top coat 20 and the wear layer 14, a sufficient temperature for a sufficient time is utilized. Typically, this temperature is from about 350° F to about 400° F for a time of from about 0.8 minute to about 3 minutes, in one embodiment, RTP 35096v1 from about 1 minute to about 1.5 minutes. Alternatively, the top coat can be applied to the mechanically embossed wear layer by any of the conventional coating apparatus and conventionally cured by heat, ultraviolet light, and the like.
FXAMPT .F~
F~rer~rnr ~ i A felt substrate having a thickness of approximately 25 mils is substantially uniformly coated with an expandable foam layer of a polyvinyl chloride plastisol containing a blowing agent with a reverse roll coater. The expandable foam layer has a wet applied average thickness of about 10 mils. Thereafter, the expandable foam layer is jelled to a relatively firm condition by heating to a temperature of approximately 300° F for approximately 17 seconds on heated drum without expansion of the foam layer. A print ink composition containing an inhibitor consistent with those described herein is printed and dried on the jelled expandable foam layer by a conventional rotogravure printing apparatus to form a print layer. The print layer is printed in a pattern design. A clear, non-foaming polyvinyl chloride plastisol wear layer having an applied thickness of approximately 10 mils is coated onto the print layer by a reverse roll coater. The wear layer is jelled on a heated drum at a temperature of approximately 300° F for approximately 10 seconds to a relatively firm condition without expansion of the foam layer. A top coat of a cross-linkable polyurethane-melamine resin having a wet applied average thickness of approximately 1 mil is coated onto the jelled wear layer by a reverse roll coater to form a coated web.
The coated web is passed through a fusion oven at a temperature of approximately 380° F for approximately 1 minute to expand and cure the foam layer, cure the wear layer, cure the top coat, and fuse all resinous layers to form a surface covering. The portions of the foam layer in contact with the printed pattern of the print layer did not expand, thereby chemically embossing the printed pattern into the foam layer.
Immediately upon exiting the fusion oven, the surface covering is tempered to approximately 250° F by passing the surface covering in an "S"
configuration of RTP 35096v1 between two water cooled tempering rollers with a wrap on each tempering roller is approximately 180°, substantially as described above. The top coat of the surface coating is then heated in a high temperature oven of a bank of infra-red radiant heaters to a substantially uniform surface temperature of approximately 350° F, while the temperature of the substrate as the surface covering exits the high temperature oven is approximately 290° F Immediately thereafter, the surface covering enters the embosser nip, which is spaced from the high temperature oven so that the top coat has substantially no temperature drop. The embosser nip is formed by the water cooled chrome plated steel embosser roll having a pattern on the surface thereof and the chrome plated steel back-up roll described herein and has a gap of approximately SO
mils. Upon entering the embosser nip, the pattern of the embossing roll mechanically embosses the top coat of the surface covering. Embossing roll surface temperature is maintained at approximately 80° F, thereby setting the mechanically embossed pattern and forming the mechanical and chemical embossed surface covering. Upon cooling to ambient temperature, the mechanical and chemical embossed surface covering is found to be acceptably and permanently embossed.
nor a ~~rnr ~ ~
The mechanical and chemical surface covering of Example 1 is mechanically embossed in register as follows. Phase registration is conducted by reducing the rotation rate of the embossing roll with respect to the surface covering rate through the embosser nip. The top coat slipped on the embossing roll without either damage to the surface covering or fading of the embossed pattern on the top coat. As a result the mechanically embossed pattern is placed in phase with the printed pattern of the surface covering.

A felt substrate having a thickness of approximately 10 mils is substantially uniformly coated with a polyvinyl chloride HMC layer of approximately 25 mils, which is applied by a calender as substantially described above. The substrate and RTP 35096v1 HMC layer are tempered to approximately 75° F. An expandable foam layer of a polyvinyl chloride plastisol containing a blowing agent is applied with a blade coater.
The expandable foam layer has a wet applied average thickness of about 10 mils.
Thereafter, the expandable foam layer is jelled to a relatively firm condition by heating to a temperature of approximately 300° F for approximately 6 seconds on heated drum without expansion of the foam layer. A print ink composition containing an inhibitor consistent with those described herein is printed and dried on the jelled expandable foam layer by a conventional rotogravure printing apparatus to form a print layer. The print layer is printed in a pattern design. A clear, non-foaming polyvinyl chloride plastisol wear layer having an applied thickness of approximately 10 mils is coated onto the print layer by a blade coater to form the coated web. The coated web is passed through a fusion oven at a temperature of approximately 400° F
for approximately 1 minute to expand and cure the foam layer, cure the wear layer, cure the top coat, and fuse all resinous layers to form a surface covering.
The portions of the foam layer in contact with the printed pattern of the print layer did not expand, thereby chemically embossing the printed pattern into the foam layer.
Immediately upon exiting the fusion oven, the surface covering is tempered to approximately 240°
F by passing the surface covering in an "S" configuration of between two water cooled tempering rollers with a wrap on each tempering roller is approximately 200°, substantially as described above. The wear layer of the surface coating is then heated in a high temperature oven of a bank of infra-red radiant heaters to a substantially uniform surface temperature of approximately 275° F, while the temperature of the substrate as the surface covering exits the high temperature oven is approximately 265° F. Immediately thereafter, the surface covering enters the embosser nip, which is spaced from the high temperature oven so that the wear layer has substantially no temperature drop. The embosser nip is formed by the water cooled chrome plated steel embosser roll having a pattern on the surface thereof and the chrome plated steel back-up roll described herein and has a gap of approximately 42 mils. Upon entering the embosser nip, the pattern of the embossing roll mechanically embosses the wear layer of the surface covering. Embossing roll surface temperature is maintained at RTP 35096v1 approximately 80° F, thereby setting the mechanically embossed pattern and forming the mechanical and chemical embossed surface covering. Upon cooling to ambient temperature, the mechanical and chemical embossed surface covering is found to be acceptably and permanently embossed.
Although the invention has been described in detail for the purpose of illustration, it is understood that such detail is solely for that purpose, and variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention which is defined by the following claims.

RTP 35096v1

Claims

1. A method of manufacturing a mechanical and chemical embossed surface covering comprising:
a) forming a web comprising a substrate, a curable wear layer, an expandable foam layer between the substrate and the wear layer, and at least one inhibitor composition disposed as a pattern proximate the expandable foam layer;
b) coating the wear layer with a cross-linkable top coat to form a coated web;
c) heating the coated web to a temperature at which the top coat is substantially cross-linked and cured, the wear layer is substantially softened, the foam layer expands to some extent, and the pattern is chemically embossed to form a surface covering;
d) then tempering the surface covering to a temperature above ambient temperature;
e) then heating the top coat of the surface covering;
f) then mechanically embossing at least one surface texture onto the top coat;
and g) then setting the at least one surface texture to form the mechanical and chemical embossed surface covering.

2. The method of claim 1, wherein the mechanical embossing is done in register with the chemical embossing.

3. The method of claim 2, wherein a first mechanically embossed texture is applied to a first region of the top coat and a second mechanically embossed texture applied to a second region of the top coat.

4. The method of claim 2, wherein the mechanical embossing imparts a texture to a selected chemically embossed region and at least one different texture to another region of the top coat.

5. The method of claim 4, wherein the selected chemically embossed region corresponds to a grout line.

6. The method of claim 1, wherein the at least one inhibitor composition comprises a pigmented printing ink composition.

7. The method of claim 1, further comprising at least one print layer being disposed within the web.

8. The method of claim 7, wherein the at least one print layer forms a printed design.

9. The method of claim 8, wherein the mechanical embossing is done in register with the printed design pattern.

10. The method of claim 9, wherein a first mechanically embossed texture is applied to a first region of the top coat and a second mechanically embossed texture applied to a second region of the top coat.

11. The method of claim 9, wherein the mechanical embossing imparts a texture to a selected chemically embossed region and at least one different texture to another region of the top coat.

12. The method of claim 11, wherein the selected chemically embossed region corresponds to a grout line.

13. A method of manufacturing a mechanical and chemical embossed surface covering comprising:
a) forming a web comprising a substrate, an expandable foam layer operably connected to the substrate, and at least one inhibitor composition disposed as a pattern proximate the expandable foam layer;
b) coating the expandable foam layer with a wear layer to form a coated web;
c) heating the coated web to a temperature at which the wear layer is substantially softened, the foam layer expands to some extent, and the pattern is chemically embossed to form a surface covering;
d) then tempering the surface covering to a temperature above ambient temperature;

e) then heating the wear layer of the surface covering;
f) then mechanically embossing at least one surface texture onto the wear layer; and g) then setting the at least one surface texture to form the mechanical and chemical embossed surface covering.

14. The method of claim 13, wherein the mechanical embossing is done in register with the chemical embossing.

15. The method of claim 14, wherein a first mechanically embossed texture is applied to a first region of the wear layer and a second mechanically embossed texture applied to a second region of the wear layer.

16. The method of claim 14, wherein the mechanical embossing imparts a texture to a selected chemically embossed region and at least one different texture to another region of the wear layer.

17. The method of claim 16, wherein the selected chemically embossed region corresponds to a grout line.

18. The method of claim 13, wherein the at least one inhibitor composition comprises a pigmented printing ink composition.

19. The method of claim 13, further comprising at least one print layer being disposed within the web.

20. The method of claim 19, wherein the at least one print layer forms a printed design.

21. The method of claim 20, wherein the mechanical embossing is done in register with the printed design pattern.

22. The method of claim 21, wherein the mechanical embossing imparts a texture to a selected chemically embossed region and at least one different texture to another region of the wear layer.

23. The method of claim 22, wherein the selected chemically embossed region corresponds to a grout line.

24. A mechanical and chemical embossed surface covering made in accordance with any of claims 1-23.

25. A chemically and mechanically embossed surface covering comprising:
a) a substrate;
b) a foam layer disposed on the substrate, wherein the foamed layer has a chemically embossed pattern imposed therein;
c) a wear layer disposed on the foam layer;
d) a mechanically embossed, cross-linked top layer disposed on the wear layer, wherein the top layer has at least one surface texture mechanically embossed in register with the chemically embossed pattern.

26. The surface covering of claim 25, further comprising at least one print layer disposed on the foam layer.

27. The surface covering of claim 26, wherein the top layer has at least two surface textures mechanically embossed in register with the chemically embossed pattern.

28. A chemically and mechanically embossed surface covering comprising:
a) a substrate;
b) a foam layer disposed on the substrate, wherein the foamed layer has a chemically embossed pattern imposed therein; and c) a wear layer disposed on the foam layer, the wear layer having a surface texture mechanically embossed in register with the chemically embossed pattern.

29. The surface covering of Claim 28, wherein the mechanical embossed surface texture is in register with a chemically embossed grout line.

30. The surface covering of Claim 28, further comprising at least one print layer disposed on the foam layer.

31. The surface covering of Claim 30, wherein the wear layer has a second surface texture mechanically embossed in register with a pattern of the print layer.

32. The method of claims 7 or 19, wherein the print layer adjoins the expandable foam layer.