Patent Application
20080044677
The invention relates to decorative laminates which incorporate a photoluminescent material. The term “photoluminescent” as used herein denotes a material which is either visibly phosphorescent (i.e., where there is a continued luminescence after termination of the exciting ultraviolet radiation), or visibly fluorescent (i.e., where the luminescence ceases as soon as the exciting ultraviolet radiation is removed). Preferably, the photoluminescent materials used for the present invention are fluorescent.
Referring to
Disposed above the core layer 20 is a decorative layer 30 which comprises a single cellulosic sheet, preferably a sheet of alpha cellulose paper. Using a printing composition including a suitable amount of a photoluminescent material, a plurality of geometric patterns (
In accordance with the invention, a second set of foul lines 50, dots 60 and darts 70 may be printed on the decorative layer sheet using the photoluminescent material. The photoluminescent patterns 50, 60, 70 may be disposed next to the printed patterns 52, 62, 72 visible under normal light. Alternatively, some of the bowling lane patterns such as the dots 60 and darts 70 may be printed such that they outline (i.e., are disposed over) the traditional dots 62 and darts 72. Additional design graphics such as, for example, a logo 80, swirled lines 90 and the like, which are visible under ultraviolet light, may also be printed using the photoluminescent material onto the decorative layer sheet to enhance the bowling experience. As illustrated in
The printing composition includes a photoluminescent material dispersed in a suitable vehicle which offers the flow characteristics desired for the selected printing method. The photoluminescent material is provided in an amount which causes the printed patterns to be visibly luminescent in the decorative laminate 10. Many types of known ultraviolet light sensitive dyes or pigments, both in dry and liquid form, may be used. Selection of a particular dye or pigment will typically depend upon the desired color to be generated when the pattern luminesces in the presence of ultraviolet light. In addition, the selected photoluminescent dyes or pigments in general must be able to withstand the heat and pressure to which the layers are exposed during the lamination process. A preferred photoluminescent material is Leucophor BCR™, available from Clariant Corp. of Charlotte, N.C. Leucophor BCR™ is a stilbene material supplied as a liquid having about 49% solids and which generates a blue color upon luminescence. Other preferred photoluminescent materials include APO-13 (red upon luminescence), APO-15 (orange), and APO-18 (green)—all pigments that are largely invisible under normal light, from Dayglo Color Corporation of Cleveland, Ohio. Also, PF-09 (violet), PF-02 (yellow), PF-R7 (red), PF-03 (orange), PF-01 (green), and PF-OB (white)—all pigments that are largely invisible under normal light, from Risk Reactor of Huntington Beach, Calif. Further, Uvitex NFW Liquid (blue) and Uvitex OB pigment (blue/green)—both pigments that are largely invisible under normal light, from Ciba Specialty Chemicals of Mobile, Ala. Other photoluminescent materials may be utilized, as should be apparent to one of ordinary skill in the art in light of the teachings herein, such that a particular pattern (e.g., the logo 80) may be visibly luminescent at a certain color when exposed to ultraviolet light, and may also be visible at the same or a different color when viewed under normal light.
The photoluminescent pigment or dye may be combined with conventional printing inks with which the selected photoluminescent pigment or dye is compatible and can be readily dispersed. For example, the photoluminescent pigment or dye may be combined with a Clear Screen Print Extender™, commercially available from Gotham Ink of Marlboro, Mass., or NAZDAR Clear 2700 AquaSafe Gloss Screen Ink 2727 Overprint Clear, from NAZDAR of Shawnee, Kans. As will be appreciated by those skilled in the art, the printing composition may also include suitable amounts of other additives, such as viscosity modifiers, heat stabilizers, wetting agents, binders or the like. Generally, when the patterns 50, 60, 70, 80, 90 are printed onto the decorative layer sheet using a known screen printing technique, each pattern or all patterns of one color are printed separately, one at a time, in the overall printing process.
In a preferred embodiment, and as disclosed hereinabove, the decorative layer sheet is dry in that it lacks any impregnating resin. However, in the alternative, once the decorative layer sheet has been provided with the desired patterns and designs, the sheet may then be impregnated with a transparent resin as is conventional. Examples of transparent resins include melamine, polyester, acrylics, epoxy, amino, silicone, etc. A melamine-formaldehyde resin is preferred.
The decorative laminate 10 may also include the optional overlay layer 40 comprising one or more sheets or cellulosic paper impregnated with a suitable transparent resin, such as melamine-formaldehyde. High-quality alpha cellulose paper is preferred for the overlay layer 40. In general, the overlay layer 40 may be utilized in certain applications (e.g., bowling lanes) where the layer 40 is needed to protect the underlying decorative layer 30. In an alternative embodiment of the present invention, instead of the plurality of printed patterns 50, 60, 70, 80, 90 that are visibly luminescent when exposed to ultraviolet light being formed in the single sheet of the decorative layer 30, the patterns 50, 60, 70, 80, 90 may be printed on one of the sheets of the overlay layer 40, using the teachings herein. Preferably, the sheet of the overlay layer 40 on which the patterns are printed may be a dry sheet—one lacking any resin impregnation. By having the printed patterns 50, 60, 70, 80, 90 on the overlay layer 40 instead of on the decorative layer 30, the overall brightness of the patterns may be somewhat brighter since they are closer to the overall top surface of the decorative laminate 10 used for the bowling lane.
The core layer 20, the decorative layer 30 and the optional overlay layer 40 are stacked in a superimposed relationship between steel press plates or the like. As will be appreciated by those skilled in the art, an additional decorative layer 94 and an overlay layer 96 (
When a source of ultraviolet light is provided in a preferred range of, for example, 200-400 nm, the light penetrates the overlay layer 40 and impinges upon the decorative layer 30. As a result, the photoluminescent material printed on the decorative layer sheet emits luminescent radiation such that the printed patterns 50, 60, 70, 80, 90 are visible. Depending upon the photoluminescent material used, the amount of such material used, the intensity of the source of ultraviolet light, and the color of the background, it may be necessary to reduce the level of visible light impinging upon the decorative laminate 10 to enhance the visibility of the luminescent patterns 50, 60, 70, 80, 90.
In an alternate embodiment of the invention, the printing composition includes a suitable amount of a photoluminescent material that is applied to the entire surface of the sheet forming the decorative layer 30 or to one of the sheets forming the overlay layer 40. Any conventional printing technique may be employed. In this manner, the entire surface of the resulting decorative laminate 10 may be made to emit visible luminescent radiation, preferably of a single color, in the presence of ultraviolet light.
In still another embodiment of the invention, one or more of the overlay layer 40 and/or the decorative layer 30 are prepared as discussed above by printing with a photoluminescent material. The decorative layer 30 and, optionally, the overlay layer 40, are then incorporated into a low pressure laminate. The decorative layer 30 is stacked in a superimposed relationship with a rigid substrate, such a particle board, fiber board or the like. Selected ones of the layer papers are impregnated with a resin in the same manner as for the high pressure laminates discussed above, although typically, as appreciated by those skilled in the art, a higher catalyst level is employed with a low pressure or thermofused laminate. The layers are placed in a hot press between steel press plates and subjected to a relatively low pressure and temperature for a time sufficiently long enough to cure the laminating resins impregnating the respective layers, as is conventional.
The following examples are illustrative of the present invention and do not constitute any limitation with regard to the subject matter of the invention.
A first solution may be prepared using 98 gms of Clear Screen Print Extender™, available from Gotham Ink of Marlboro Mass. with 2 gms of APO-13, Invisible Red pigment from Dayglo Color Corporation of Cleveland Ohio. The solution may be screen printed in a pattern onto a dry decorative paper with a maple grain design.
A second solution may be prepared using 98 gms of Clear Screen Print Extender™, with 2 gms of APO-15, Invisible Orange pigment from Dayglo Color Corporation. The solution may again be screen printed in a pattern onto the dry decorative paper. As disclosed hereinabove, with the typical screen printing method, each pattern or all patterns of one color are printed separately, one at a time, in the overall printing process.
Depending on the particular application for the decorative laminate 10 and/or on the number of patterns and/or colors desired, additional patterns of various colors may be screen printed in the decorative layer sheet using the following additional solutions:
(3) 98 gms of Clear Screen Print Extender™ with 2 gms of APO-18, Invisible Green pigment from Dayglo Color Corporation;
(4) 90 gms of Clear Screen Print Extender™ with 10 gms of PF-09, Invisible Violet pigment from Risk Reactor;
(5) 90 gms of Clear Screen Print Extender™ with 10 gms of PF-02, Invisible Yellow pigment from Risk Reactor;
(6) 90 gms of Clear Screen Print Extender™ with 10 gms of PF-R7, Invisible Red pigment from Risk Reactor;
(7) 90 gms of Clear Screen Print Extender™ with 10 gms of PF-03, Invisible Orange pigment from Risk Reactor;
(8) 90 gms of Clear Screen Print Extender™ with 10 gms of PF-01, Invisible Green pigment from Risk Reactor;
(9) 90 gms of Clear Screen Print Extender™ with 10 gms of PF-OB, Coconut Bright White pigment from Risk Reactor;
(10) 80 gms of NAZDAR Clear 2700 AquaSafe Gloss Screen Ink 2727 Overprint Clear with 20 gms of Uvitex NFW Liquid from Ciba Specialty Chemicals; and
(11) 80 gms of NAZDAR Clear 2700 AquaSafe Gloss Screen Ink 2727 Overprint Clear with 20 gms of Uvitex OB pigment, from Ciba Specialty Chemicals.
A prototype decorative laminate 10 may be produced having the following layers stacked in a superimposed relationship as follows: one light basis weight melamine-formaldehyde impregnated overlay layer sheet; one high wear overlay layer melamine-formaldehyde impregnated sheet; the screen printed dry decorative layer sheet; four phenolic impregnated kraft paper sheets; one core dry decorative sheet; one high wear overlay melamine-formaldehyde impregnated sheet; and one light basis weight melamine-formaldehyde impregnated overlay sheet. The sheets may be positioned between steel press plates and subject to approximately 1200 psi at a maximum temperature of about 300° F. for a total of about 20 minutes.
The screen printed patterns may be difficult to see under normal lighting, but may exhibit excellent fluorescence when exposed to a source of ultraviolet light.
A decorative laminate 10 may be prepared similar to that of Example 1 hereinabove, except that instead of the decorative layer sheet being printed with the desired photoluminescent patterns, a dry overlay layer sheet is printed with the desired photoluminescent patterns having the desired colors using methods similar to those described hereinabove with respect to Example 1.
A decorative laminate 10 may be prepared similar to that of either Examples 1 or 2, except that the resulting prototype decorative laminate 10 may be produced having the following layers stacked in a superimposed relationship as follows: one light basis weight melamine-formaldehyde impregnated overlay layer sheet; one high wear overlay layer melamine-formaldehyde impregnated sheet; the screen printed dry decorative layer sheet; and four phenolic impregnated kraft paper sheets. The sheets may be positioned between steel press plates and subject to approximately 1200 psi at a maximum temperature of about 300° F. for a total of about 20 minutes. This is an example of an “unbalanced” design of the decorative laminate 10.
It will be obvious to those skilled in the art that various changes may be made without departing from the scope of the present invention and that the invention is not to be considered limited to what is described and exemplified in the specification.
