Patent ID: 12213555

DETAILED DESCRIPTION

The following discussion and accompanying figures disclose methods and systems for color printing onto any substrate (e.g., textiles or synthetic materials), the printed material having any color or opacity, and achieving color management, color durability, and abrasion resistance through printing of multiple layers of intermixed white and color printed material. The disclosed methods and systems may use any suitable 3D printing system.

As used throughout this disclosure, the terms “color-accurate color” and “color accuracy” refer to the accurate representation, simulation, depiction, proofing, viewing, or otherwise the observation of one of more colors printed consistent with an embodiment of the disclosure on a white or a nonwhite substrate, such that the printed one or more colors achieve substantially indistinguishable visible color differentiation from one or more colors in printed on a white substrate with the CMYK color model. As also used throughout this disclosure, the terms “color printing,” “inkjet printing,” “CMYK printing,” “CMYK inkjet printing,” and “color inkjet printing” refer to printing of an image by ejecting droplets of one or more inks onto a substrate. Contrary to known “color printing,” “inkjet printing,” “CMYK printing,” “CMYK inkjet printing,” and “color inkjet printing,” however, the disclosed “color printing,” “inkjet printing,” “CMYK printing,” “CMYK inkjet printing,” and “color inkjet printing” achieve color accuracy on a substrate of any color, whereas known printing techniques require printing onto a white substrate, such as white paper, in order to achieve the same or similar color accuracy on the substrate. As also used throughout this disclosure, the term “color durability” refers to the ability of a printed color to resist or otherwise minimize the visibility of scratches, abrasions, or other marring or damage to the printed color.

As used throughout this disclosure, the term “substrate” refers to any material on which printing consistent with the embodiments of the disclosure may occur, for example, paper, plastic, metal, articles of apparel, sports equipment, a textile, a natural fabric, a synthetic fabric, a knit, a woven material, a nonwoven material, a mesh, a leather, a synthetic leather, a polymer, a rubber, and a foam, or any combination of them.

Consistent with an embodiment, an exemplary substrate may be, for example, a fabric. As used throughout this disclosure, “fabric” may be used to refer generally to materials chosen from any textile, natural fabric, synthetic fabric, knit, woven material, nonwoven material, mesh, leather, synthetic leather, polymers, rubbers, and foam, and may also be used to refer to any natural or synthetic fiber or material, such as, for example, cotton, wool, linen, silk, nylon, elastane (i.e., spandex), polyester, rayon, and olefins (i.e., polypropylene), and may further comprise combinations of any of these materials. Also as used throughout this disclosure, the terms “printing” or “printed,” and “depositing” or “deposited,” are each used synonymously, and are intended to refer to the association of a material from a source of the material to a receiving surface or object.

Consistent with an embodiment, an exemplary substrate may also be, for example, an article of apparel. As used throughout this disclosure, the terms “article of apparel” and “fabric” thus include any textile and any materials associated with or made from fabric, including a sock or a shirt, and may also be applied to any article of clothing, apparel, or equipment. For example, the disclosed embodiments may be applied to hats, caps, shirts, jerseys, jackets, socks, shorts, pants, undergarments, athletic support garments, gloves, wrist/arm bands, sleeves, headbands, any knit material, any woven material, any nonwoven material, sports equipment, etc. Thus, as used throughout this disclosure, the term “article of apparel” may refer to any apparel or clothing, including hats, caps, shirts, jerseys, jackets, socks, shorts, pants, undergarments, athletic support garments, gloves, wrist or arm bands, sleeves, headbands, any knit material, any woven material, any nonwoven material, etc.

In accordance with the systems and methods described throughout this disclosure, there is provided a method of color printing, comprising: printing at least a first layer of ink comprising a white ink and at least one color ink, the first layer of ink having a predetermined first ratio of white ink to color ink; and printing at least a second layer of ink comprising the white ink and the at least one color ink, the second layer of ink having a predetermined second ratio of white ink to color ink different from the first ratio, wherein the first ratio is greater than the second ratio.

In accordance with the systems and methods described throughout this disclosure, there is also provided a method of color management, comprising: printing at least one color comprising multiple printed layers onto a substrate, the multiple printed layers comprising: at least a first layer of ink comprising a white ink and at least one color ink, the first layer of ink having a predetermined first ratio of white ink to color ink; and at least a second layer of ink comprising the white ink and the at least one color ink, the second layer of ink having a predetermined second ratio of white ink to color ink different from the first ratio, wherein the first ratio is greater than the second ratio.

In accordance with the systems and methods described throughout this disclosure, there is provided a method of hot-melt printing, comprising: printing a melt of an opaque material and at least one translucent pigmented material onto a substrate, the opaque material and the at least one translucent pigmented material being supplied from different printheads, wherein the opaque material and the at least one translucent pigmented material mix on the substrate, the printing further comprising: printing at least one color comprising multiple printed layers of the opaque material and the at least one translucent pigmented material, the multiple printed layers comprising: at least a first layer comprising the opaque material and the at least one translucent pigmented material, the first layer having a predetermined first ratio of opaque material to translucent pigmented material; and at least a second layer comprising the opaque material and the at least one translucent pigmented material, the second layer having a predetermined second ratio of opaque material to translucent pigmented material different from the first ratio, wherein the first ratio is greater than the second ratio.

In accordance with the systems and methods described throughout this disclosure, there is provided a method of printing a desired color onto a nonwhite substrate by additive printing of intermixed translucent color ink and opaque white ink, comprising: printing at least a first layer of ink onto the nonwhite substrate comprising a first mixture of an opaque white ink and at least one substantially translucent color ink, the first layer of ink having a predetermined first ratio of white ink to color ink being less than or equal to 1:1; and printing at least a second layer of ink onto the nonwhite substrate comprising a second mixture of the opaque white ink and the at least one substantially translucent color ink, the second layer of ink having a predetermined second ratio of white ink to color ink being less than or equal to 1:1, wherein the first ratio and the second ratio are substantially equal, and wherein a sum of the first printed layer and second printed layer produces the desired color being optically indistinguishable in the visible spectrum from the same color printed onto a white substrate using opaque color inks.

In accordance with the systems and methods described throughout this disclosure, there is also provided a method of color management, comprising: printing at least one desired color onto a nonwhite substrate by additive printing of intermixed translucent color ink and opaque white ink, the desired color comprising multiple printed layers, the multiple printed layers comprising: at least a first layer of ink comprising a first mixture of an opaque white ink and at least one substantially translucent color ink, the first layer of ink having a predetermined first ratio of white ink to color ink being less than or equal to 1:1; and at least a second layer of ink comprising a second mixture of the opaque white ink and the at least one substantially translucent color ink, the second layer of ink having a predetermined second ratio of white ink to color ink being less than or equal to 1:1, wherein the first ratio and the second ratio are substantially equal, and wherein a sum of the first printed layer and second printed layer produces the desired color being optically indistinguishable in the visual spectrum from the same color printed onto a white substrate using opaque color inks.

In accordance with the systems and methods described throughout this disclosure, there is provided a method of hot-melt printing, comprising: printing a melt of an opaque material and at least one translucent pigmented material onto a nonwhite substrate, the opaque material and the at least one translucent pigmented material being supplied from different printheads, wherein the opaque material and the at least one translucent pigmented material mix on the substrate, the printing further comprising: printing at least one desired color comprising multiple printed layers of the opaque material and the at least one translucent pigmented material, the multiple printed layers comprising: at least a first layer comprising the opaque material and the at least one translucent pigmented material, the first layer having a predetermined first ratio of opaque material to translucent pigmented material being less than or equal to 1:1; and at least a second layer comprising the opaque material and the at least one translucent pigmented material, the second layer having a predetermined second ratio of opaque material to translucent pigmented material being less than or equal to 1:1, wherein the first ratio and the second ratio are substantially equal, and wherein a sum of the first printed layer and second printed layer produces the desired color being optically indistinguishable in the visual spectrum from the same color printed onto a white substrate using opaque color inks.

Additional features and advantages will be set forth in part in the description that follows, being apparent from the description or learned by practice of embodiments. Both the foregoing description and the following description are exemplary and explanatory, and are intended to provide further explanation of the embodiments as claimed.

The CMYK color model used in inkjet printing typically relies on the presence of a white substrate, such as a white piece of paper, to achieve accurate representation of the colors of one or more printed color inks. “CMYK” refers to four color inks used in color inkjet printing: “C” for cyan, “M” for magenta, “Y” for yellow, and “K” for black. Color inkjet printers may contain print heads, inkjet cartridges, or ink reservoirs of cyan, magenta, yellow, and black.

CMYK printing may produce or approximate essentially any color in the visible spectrum by printing and intermixing various combinations of color ink, as exemplified by the CMYK Venn diagram shown inFIG.1. Referring toFIG.1, cyan, magenta, and yellow inks may be intermixed during printing to produce one or more colors of red, green, and blue as shown. Further intermixing of colors during printing may be used to produce many more colors beyond the primary colors of red, green, and blue, or of cyan, magenta, and yellow, as shown inFIG.1. Cyan, magenta, and yellow inks may also be intermixed to produce black. Black produced as shown in the CMYK Venn diagram ofFIG.1, however, may appear visually to an observer as a lighter black instead of a very dark or true black. Therefore, CMYK printers may also contain a separate cartridge or reservoir filled with black ink for printing of a true black.

CMYK printed inks are generally considered subtractive in nature, in that they essentially reduce the whiteness of an underlying white substrate when viewed by reflected visible light by at least partially masking it with one or more layers of printed CMYK color inks. CMYK inks are also typically water-based, and intermix and dry on the surface of the substrate after printing.

Printing of the CMYK color inks typically requires a white substrate because the printed inks are at least translucent, and color-accurate printing relies on light reflected from an underlying white substrate through the printed color inks to achieve color in the visible spectrum that is recognizable to the human eye. Referring toFIG.2, and consistent with an embodiment, an inkjet printer100is shown comprising inkjet cartridges105. Cartridges105comprise cartridge110for cyan (“C”), cartridge112for magenta (“M”), cartridge114for yellow (“Y”), cartridge116for black (“K”), and two cartridges118,120for white (“W”). While two cartridges for white are depicted inFIG.2, consistent with an embodiment, printer100may contain only one cartridge for white, or may contain more than one cartridge for white, as shown. Moreover, the ink contained in white cartridges118,120may be an opaque ink, for reasons explained further below.

Still referring toFIG.2, and consistent with an embodiment, cartridges105may print droplets of ink125onto substrate130. Substrate130may be a piece of paper, or any other substrate, such as a textile or fabric, as described above. Ink droplets125may be ejected from one or more of cartridges105and directed toward substrate130as shown by ink droplet movement direction135. As ink droplets125are printed, cartridges105may be moved across substrate130as shown by direction140, while substrate130may be moved perpendicular to direction140as shown by direction145, both to facilitate printing. In this manner, printing of features150, such as images, graphics, designs, and text, may be achieved on substrate130.

Consistent with an embodiment, use of the CMYK color model and printing techniques may be accomplished on white or on nonwhite substrates. In order to print color onto nonwhite substrates using a printer similar to that shown inFIG.2, layers printed using an existing printing technique200are shown inFIG.3. Referring toFIG.3, for example, layers printed using existing printing technique200first require the reproduction, simulation, or creation of an underlying white substrate in order to achieve color accuracy in a final printed color printed thereon.FIG.3thus shows a perspective view of a sequence of printed layers printed via an existing printing technique200used to print color ink over a nonwhite substrate, along with a depiction of the printheads used for printing each of the respective printed layers.

As shown inFIG.3, portions of multiple printed layers205are shown in perspective view. Layers205comprise six printed layers of white210,212,214,216,218, and220. Six layers of white are shown inFIG.3, although more or less layers of white may be printed using existing printing technique200. White layers210,212,214,216,218, and220are used to create a white substrate onto which color printing may occur. Color layer222is the final printed layer, printed over the white layers, and which may be any color printed according to the CMYK model.

Still referring toFIG.3, a depiction of print cartridges or heads230shows the inks used print the six layers of white210,212,214,216,218, and220. For example, to print the six layers of white that create a white substrate via printed ink, white ink cartridges232,234are used to eject droplets of white ink236, while the remaining color cartridges remain inactive. White ink236may be an opaque ink, which will reflect visible light impinging thereon in order to simulate a white substrate underneath subsequently printed one or more translucent color inks. White ink236also serves to cover the regions of the nonwhite substrate on which subsequent printing of color will occur.

In addition, depiction of print cartridges or heads240inFIG.3shows the inks used to print color layer222upon completion of printing the six opaque layers of white. Color layer222may be formed from printing a translucent ink to enable reflection of visible light from the underlying printed opaque white ink236. For example, color layer222may be a printed layer of color-accurate green, achieved by using ink printed from cyan cartridge242and yellow cartridge244as shown inFIG.3. Cartridges242and244are thus used to eject droplets of translucent cyan ink246and translucent yellow ink248, while the remaining cartridges are inactive. Droplets246and248intermix upon printing onto the uppermost white layer220to form, in the example shown inFIG.3, a color-accurate green color in color layer222. The color-accurate green color of color layer222may be observed visually by viewing light reflected from underlying white layer220passing through layer222to an observer's eyes. Even though green color is used in the example described with reference toFIG.3, any color may be printed using the CMYK color model or palette. Such color may then be subsequently observed, so long as a white substrate is first created underneath the final printed color layer.

Still referring toFIG.3, a drawback to layers printed using existing printing technique200is that it requires printing of many extra layers of ink in order to print color-accurate colors on a nonwhite substrate. For example, several layers of opaque white ink must first be printed in order to effectively simulate a white substrate underlying a subsequently printed color layer. This technique requires more printing time, more printed layers, and usage of a higher density and amount of printed ink. Moreover, if the final printed color layer is scratched, abraded, or otherwise marred or damaged, it is likely that the printed color would be removed in the region of the scratch, abrasion, or mar. Thus, it is likely that one or more of the underlying white layers would be exposed, thereby displaying an undesirable high contrast between the final printed color layer and the exposed underlying white layer(s). Thus, the cost to print on a nonwhite substrate using the existing technique is greater and has more complications to achieving a final printed color-accurate color.

In contrast, and consistent with an embodiment,FIG.4shows a perspective view of an exemplary sequence of printed ink layers that produce a color-accurate color over a nonwhite substrate, along with a depiction of the printheads used for each of the respective printed layers according to printing technique300. As will be described with reference toFIG.4, printing technique300differs from known techniques in that printer100may print white ink at the same time as color ink. The printed pattern of ink droplets may comprise a stochastic dot pattern, chaotic in nature, which mixes with itself either as the ink is ejected onto the substrate or immediately upon printing onto the substrate. The printed white ink and color ink may thus intermix upon printing onto a substrate, analogous to what the print industry may identify as a solid color or spot color. The intermixed and printed white and color inks are mixed on demand and upon printing onto a substrate in a manner analogous to house paint, such that printing multiple layers of this intermixed white and color inks builds up opacity over the course of multiple printed layers. This built-up opacity avoids the need to simulate or reproduce a white substrate underneath the printed color layer, in contrast to known printing technique200, and allows for printing color-accurate colors on nonwhite substrates with fewer printed layers and less ink used.

As shown inFIG.4, portions of multiple printed layers305printed using printer100are shown in perspective view. Layers305comprise four layers of printed material310,312,314, and316. Four layers of intermixed white and color inks are shown in the example ofFIG.4, although more or less layers may be printed to achieve printing of a desired color-accurate color. The desired color-accurate color for printing will thus be built-up over the course of printing each of layers310,312,314, and316by decreasing the ratio of white ink to color ink with each successive printed layer. That is, the ratio of white ink to color ink in first printed layer310may be high, while the ratio of white ink to color ink in final printed layer316may be low. For example, the amount of white ink may decrease in each of successively printed layers310,312,314, and316, while the amount of color ink may correspondingly increase in each of successively printed layers310,312,314, and316. Details of printing technique300will be further described below.

In contrast to existing technique200, the final printed layer316printed according to printing technique300does not have to be the final desired color-accurate color printed according to the CMYK model. That is, printing technique300does not require that the uppermost printed layer solely be the color-accurate color as a standalone printed layer. Rather, it is the combination of each of printed layers310,312,314, and316that, when taken together, create the color-accuracy for a desired color printed according to the CMYK model. Because each of printed layers310,312,314, and316comprise intermixed translucent color ink and opaque white ink, the mixture of translucency and opacity of the various components of the printed layers work in concert to achieve observable color-accuracy of the final desired printed color. This may be observed when visible light passes through and reflects back from layers310,312,314, and316. This will be later described in more detail with reference toFIG.13.

Still referring toFIG.4, a depiction of print cartridges or heads330,340,350, and360shows the inks used to respectively print the exemplary four layers of intermixed color and white inks310,312,314, and316. For example, to print an exemplary color-accurate green color according to printing technique300, first printed layer310may be printed using the configuration of print heads330. As part of print heads330, cyan cartridge331, yellow cartridge333, and white cartridges332and334may be used to eject droplets of white ink336as well as droplets of cyan ink335and yellow ink337. While two white cartridges332,334are depicted, there may be one or more white cartridges in printer100as described above with reference toFIG.2. InFIG.4, white cartridges332and334are depicted qualitatively as ejecting more white ink336than cyan cartridge331is ejecting of cyan ink335, and yellow cartridge333is ejecting of yellow ink337. First layer310may thus have the highest opacity of the layers printed according to printing technique300(and hence the largest amount of printed white ink), though it may not be completely white. In first layer310, the comparatively smaller amounts of printed translucent cyan ink335and translucent yellow ink337intermix with the opaque white ink336to form layer310.

Still referring toFIG.4, second printed layer312may be printed using the configuration of print heads340. As part of print heads340, cyan cartridge331, yellow cartridge333, and white cartridges332and334may be used to eject droplets of white ink346as well as droplets of cyan ink345and yellow ink347. InFIG.4, white cartridges332and334are still depicted as qualitatively ejecting more white ink346than cyan cartridge331is ejecting of cyan ink345, and yellow cartridge333is ejecting of yellow ink347. Second layer312, however, may comprise less white ink346than first layer310comprises white ink336. That is, second layer312contains more translucent color ink than first layer310, and the opacity of first layer310may be greater than the opacity of second layer312. In second layer312, a greater amount of printed translucent cyan ink345and translucent yellow ink347intermix with the opaque white ink346, although layer312may still comprise a majority of white ink346.

Still referring toFIG.4, third printed layer314may be printed using the configuration of print heads350. As part of print heads350, cyan cartridge331, yellow cartridge333, and white cartridges332and334may be used to eject droplets of white ink356as well as droplets of cyan ink355and yellow ink357. Now, white cartridges332and334are no longer depicted as ejecting more white ink356than cyan cartridge331is ejecting of cyan ink355, and yellow cartridge333is ejecting of yellow ink357. Third layer314, like second layer312, may comprise less white ink356than second layer312comprises white ink346. That is, third layer314may comprise even more color ink than second layer312, which in turn may comprise more color ink than first layer310. Moreover, the opacity of second layer312printed according to printing technique300may be greater than the opacity of third layer314. In third layer314, an even greater amount of printed translucent cyan ink355and translucent yellow ink357intermix with the opaque white ink356, and layer314thus comprises a majority of color ink.

Still referring toFIG.4, fourth printed layer316may be printed using the configuration of print heads360. As part of print heads360, cyan cartridge331, yellow cartridge333, and white cartridges332and334may be used to eject droplets of white ink366as well as droplets of cyan ink365and yellow ink367. Now, white cartridges332and334eject substantially less white ink356than cyan cartridge331is ejecting of cyan ink365, and yellow cartridge333is ejecting of yellow ink367. Fourth layer316may comprise less white ink366than third layer314comprises white ink356. That is, fourth layer316may comprise even more color ink than third layer314, which in turn may comprise more color ink than second layer312, which in turn may comprise more color ink than first layer310. Moreover, the opacity of third layer314printed according to printing technique300may be greater than the opacity of fourth layer316. In fourth layer316, an even greater amount of printed translucent cyan ink365and translucent yellow ink367intermix with the opaque white ink366, and layer316thus comprises a greater majority of color ink than third layer312.

Thus, technique300shown inFIG.4does not require printing of separate or underlying layers of white to simulate, reproduce, or create a white substrate via printed ink. Technique300shown inFIG.4may produce one or more color-accurate colors printed additively through layers of varying ratios of intermixed translucent color inks and opaque white inks. In the example shown inFIG.4, color-accurate green color may be produced through the printing of layers310,312,314, and316. The ratio of intermixed translucent color inks to opaque white inks shown in the layers ofFIG.4may vary from low to high through each of four layers310,312,314, and316. Thus, reflection of visible light may occur through one or more of four layers310,312,314, and316, because there may be a portion of each of these layers comprising both translucent and opaque characteristics. The number of printed layers and the ratios of color to white inks therein may be calculated in order to achieve printing of desired color-accurate colors, such as color-accurate green used in the example ofFIG.4. The color-accurate green color achieved through layers310,312,314, and316, for example, may be observed by viewing light reflected from one or more of the layers and passing to an observer's eyes. Even though achievement of color-accurate green color is used in the example described with reference toFIG.4, any color or colors may be printed on a nonwhite substrate using the CMYK color model or palette with printing technique300. Such color may then be subsequently observed, without requiring the presence of a white substrate underlying the printed color layers.

Thus, as described with reference toFIG.4, and consistent with an embodiment, printing technique300may not require printing of many extra layers of ink and may not require printing of white ink layers to effect a white substrate. Printing technique300thus reduces printing time, the number of printed layers, and may achieve color-accurate color printing using less ink than with existing technique200. Moreover, if the final printed color layer is scratched, abraded, or otherwise damaged or marred, the printed color may only be partially removed in the region of the scratch, abrasion, or mar. Thus, even if one or more of the underlying printed layers would be exposed, each underlying layer still comprises a percentage of color ink and may thereby display only a low contrast between the scratched color layer and one or more layers immediately above or below. Thus, the cost to print on a nonwhite substrate using the technique300is lower than that existing technique200, and achieves a final printed color-accurate color that exhibits less contrast change when scratched, abraded, or otherwise damaged or marred.

Consistent with an embodiment,FIG.5shows a perspective view of another exemplary sequence of printed ink layers that produce a color-accurate color over a nonwhite substrate, along with a depiction of the printheads used for each of the respective printed layers according to printing technique302. As will be described with reference toFIG.5, printing technique302differs from known techniques in that printer100may print white ink at the same time as color ink similar to the embodiment described above with respect toFIG.4. Consistent with an embodiment, the printed pattern of ink droplets printed according to printing technique302may also comprise a stochastic dot pattern, chaotic in nature, which is mixed on demand, mixing with itself either as the ink is ejected onto the substrate or immediately upon printing onto the substrate. The printed white ink and color ink may thus intermix upon printing onto a substrate, analogous to what the print industry may identify as a solid color or spot color. The intermixed and printed white and color inks are mixed upon printing onto a substrate in a manner analogous to house paint, such that printing multiple layers of this intermixed white and color inks builds up opacity over the course of multiple printed layers. This built-up opacity avoids the need to simulate or reproduce a white substrate underneath the printed color layer, in contrast to known printing technique200, and allows for printing color-accurate colors on nonwhite substrates with fewer printed layers and less ink used.

As shown inFIG.5, portions of multiple printed layers307printed using printer100are shown in perspective view. Layers307comprise four layers of printed material315. Four layers of intermixed white and color inks are shown in the example ofFIG.5, although more or less layers may be printed to achieve printing of a desired color-accurate color. The desired color-accurate color for printing will thus be built-up over the course of printing each of layers315by repeating the printing of a predetermined ratio of white ink to color ink in each successive printed layer. That is, the ratio of white ink to color ink in the first printed layer may be less than or equal to 1:1, and this may be the same ratio applied to any number of successively printed layers of multiple printed layers307. Details of printing technique302will be further described below.

In contrast to existing technique200, the final printed layer315of multiple layers307printed according to printing technique302does not have to be the final desired color-accurate color printed according to the CMYK model. That is, printing technique302, like printing technique300describe with respect toFIG.4, does not require that the uppermost printed layer solely be the color-accurate color as a standalone printed layer. Rather, it is the combination of each of the layers of multiple layers307that, when taken together, create the color-accuracy for a desired color printed according to the CMYK model. Because each of the layers of multiple layers307comprise intermixed translucent color ink and opaque white ink, the mixture of translucency and opacity of the various components of the printed layers work in concert to achieve observable color-accuracy of the final desired printed color. This may be observed visually as well as during instrument testing of printed colors when considering visible light passing through and reflecting back from multiple layers307. This will be later described in more detail with reference toFIG.14.

Still referring toFIG.5, a depiction of print cartridges or heads330,340,350, and360shows the inks used to respectively print the exemplary four layers comprising multiple layers307. For example, to print an exemplary color-accurate green color according to printing technique302, first printed layer315of multiple layers307may be printed using the configuration of print heads330. As part of print heads330, cyan cartridge331, yellow cartridge333, and white cartridges332and334may be used to eject droplets of white ink376as well as droplets of cyan ink375and yellow ink377. While two white cartridges are again depicted (similar toFIG.4), there may be one or more white cartridges in printer100as described above with reference toFIG.2. InFIG.5, printing technique302qualitatively uses more white ink376than cyan ink375, and yellow ink377. First printed layer315of multiple layers307may thus have a ratio of white ink to color ink producing an opacity in between the opacity of layers314and316shown inFIG.4, and may not be completely white. For example, first printed layer315of multiple layers307may have a ratio of white ink to color ink being less than or equal to 1:1. Moreover, second, third, and fourth printed layers315of multiple layers307shown inFIG.5may have the same ratio of white ink to color ink as that of first printed layer315.

Thus, technique302shown inFIG.5likewise does not require printing of separate or underlying layers of white to simulate, reproduce, or create a white substrate via printed ink. Technique302shown inFIG.5, similar to technique300shown inFIG.4, may produce one or more color-accurate colors printed additively through layers comprising one or more predetermined ratios of intermixed translucent color inks and opaque white inks. In the example shown inFIG.5, color-accurate green color may be produced through the printing of layers315of multiple printed layers307. The ratio of intermixed translucent color inks to opaque white inks shown in the layers ofFIG.5may thus be the same ratio in each of the layers315of multiple printed layers307. Thus, reflection of visible light may occur through one or more of the four layers315shown inFIG.5, because there may be a portion of each of these layers comprising both translucent and opaque characteristics. The number of printed layers and the ratios of color to white inks therein may be calculated in order to achieve printing of desired color-accurate colors, such as color-accurate green used in the example ofFIG.5. The color-accurate green color achieved through multiple layers307, for example, may be observed by viewing light reflected from one or more of the layers and passing to an observer's eyes. Even though achievement of color-accurate green color is used in the example described with reference toFIG.5, any color or colors may be printed on a nonwhite substrate using the CMYK color model or palette with printing technique302. Such color may then be subsequently observed, without requiring the presence of a white substrate underlying the printed color layers.

Thus, as described with reference toFIG.5, and consistent with an embodiment, printing technique302may not require printing of many extra layers of ink and may not require printing of white ink layers to effect a white substrate. Printing technique302thus reduces printing time, the number of printed layers, and may achieve color-accurate color printing using less ink than with existing technique200. Moreover, if the final printed color layer is scratched, abraded, or otherwise damaged or marred, the printed color may only be partially removed in the region of the scratch, abrasion, or mar. Thus, even if one or more of the underlying printed layers of multiple layers307would be exposed, each underlying layer315still comprises a percentage of color ink and may thereby display only a low contrast between the scratched color layer and one or more layers immediately above or below. Thus, the cost to print on a nonwhite substrate using the technique302is lower than that existing technique200, and achieves a final printed color-accurate color that exhibits less contrast change when scratched, abraded, or otherwise damaged or marred.

As shown inFIG.6, and consistent with an embodiment, an exemplary generalized process450for printing color-accurate CMYK colors on nonwhite substrates begins with step452. Some or all steps in process450may be completed by a footwear, apparel, or equipment manufacturer or proprietor. In other cases, some steps described below may be accomplished by a manufacturer and other steps may be accomplished by another party including another manufacturer, proprietor, retailer, or any other entity. In some cases, one or more of the steps may be optional. In other cases, some steps may be completed in a different order. Referring toFIG.5, in step452, a desired translucent color (c) for printing is selected. Color (c) may be any color-accurate color that can be printed using the CMYK color model. In step454, a desired number of layers (n) for printing is selected, for printing the color-accurate color.

Still referring toFIG.6, in step456, each layer's printed color is calculated based on the number of layers (n). In step458, the current layer (m) is printed. In step460, progress of color printing may be evaluated to verify whether printing is finished (n=m). If printing is finished, then process450is complete. In step460, if printing is not finished, then process450may proceed to step462. In step462, printing may continue with the next layer (m=m+1) and return to step458.

As shown inFIG.7, step456is explained in greater detail. In step470, the number of layers (n) and intensity of color (c) are used to determine the color of the final layer (CF). In step472, the remaining number of layers (n−1) is calculated. Then, in step474, the color intensity for each remaining layer is calculated as a percentage of CF. In step476, CF and n are used to generate a color grading rule. In step478, the grading rule is used to compute each printed layer's color intensity. Graphical examples of the grading rule are shown inFIGS.8and9.

Referring toFIG.8, and consistent with an embodiment, a graphical representation of a grading rule is shown for the case when three layers may be printed to achieve a color-accurate printed color. In the graphical representation, the grading rule may be shown as a logarithmic function. The grading rule, however, may be a linear function, logarithmic function, exponential function, parabolic function, or any other sequence or expression, depending on the desired color for printing. Still referring toFIG.8, each layer's color intensity may be a percentage of the desired CF, based on the number of layers printed. For example, as shown inFIG.8, when three layers are printed, CF1is the percentage of color intensity for the first printed layer n=1. Similarly, CF2is the percentage of color intensity for the second printed layer n=2; and CF3is the percentage of color intensity for the third printed layer n=3. Because multiple layers are printed, the color intensity in each of the layers n=1, 2, 3 will be lower than the desired CF due to the additive nature of printing a percentage of color in each printed layer.

Referring toFIG.9, and consistent with an embodiment, another graphical representation of a grading rule is shown for the case when five layers may be printed to achieve a color-accurate printed color. In the graphical representation, the grading rule may be shown as a logarithmic function. The grading rule, however, may be a linear function, logarithmic function, exponential function, parabolic function, or any other sequence or expression, depending on the desired color for printing. Still referring toFIG.9, each layer's color intensity may be a percentage of the desired CF, based on the number of layers printed. For example, as shown inFIG.9, when five layers are printed, CF1is the percentage of color intensity for the first printed layer n=1. Similarly, CF2is the percentage of color intensity for the second printed layer n=2; CF3is the percentage of color intensity for the third printed layer n=3; CF4is the percentage of color intensity for the fourth printed layer n=4; and CF5is the percentage of color intensity for the fifth printed layer n=5. Because multiple layers are printed, the color intensity in each of the layers n=1, 2, 3, 4, 5 will be lower than the desired CF due to the additive nature of printing a percentage of color in each printed layer. In addition, the graphical representations inFIGS.8and9show, for example, that the grading rule curve may have a more shallow slope as the number of printed layers (n) increases. That is, each of CF1, CF2, CF3, CF4, and CF5may be a smaller percentage of CF in the case of printing five layers, whereas CF1, CF2, and CF3may be a larger percentage of CF in the case of printing only three layers.

As shown and described with reference toFIGS.4-9, and consistent with an embodiment, CF may be a high percentage of the desired color-accurate final color C. For example, if n=3, then CF may be approximately 95% of C; if n=4, then CF may be approximately 90% of C; if n=5, then CF may be approximately 85% of C, etc. These percentages may also vary not just based on the number of layers printed, but may also vary depending on the selected color-accurate CMYK color for printing. For example, printing of lighter colors, such as pink (described later with reference toFIG.12), may call for CF to be an even higher percentage of C (pink). Conversely, for example, printing of darker colors, such as dark blue, may call for CF to be an overall lower percentage of C (dark blue). Moreover, in the case of the embodiment described above with respect toFIG.5, the color intensity in each of the printed layers may be lower than the desired CF at a predetermined intermediate value being substantially equal in each of the printed layers n, due to the additive nature of printing a percentage of color in each printed layer.

As shown inFIG.10, and consistent with an embodiment, another exemplary generalized process500for printing color-accurate CMYK colors on nonwhite substrates begins with step505. Some or all steps in process500may be completed by a footwear, apparel, or equipment manufacturer or proprietor. In other cases, some steps described below may be accomplished by a manufacturer and other steps may be accomplished by another party including another manufacturer, proprietor, retailer, or any other entity. In some cases, one or more of the steps may be optional. In other cases, some steps may be completed in a different order. Referring toFIG.10, in step505, a desired translucent color (c) for printing is selected, along with an opaque white (w). Color (c) may be any color-accurate color that can be printed using the CMYK color model. In step510, a desired number of print layers (n) is selected, for printing the color-accurate color.

Still referring toFIG.10, in step515, color management grading (CMG) is calculated, using a computer, for printed color and white inks as a function of the number of printed layers. That is, (c+w)n, where (c, w≠0). In step515, the calculated CMG provides that each printed layer comprises a combination of printed translucent color and opaque white inks, and that the ratio of color ink to white ink in each printed layer may vary as a function of the number of layers printed.

In step520, a first layer of color ink and white ink is printed according to the calculated CMG, and the amount of color ink printed is much less than the amount of white ink printed. In step525, a second layer of color ink and white ink is printed according to the calculated CMG, and the amount of color ink printed is less than the amount of white ink printed but more color is printed than that printed in step520. In step530, a third layer of color ink and white ink is printed according to the calculated CMG, and the amount of color ink printed is more than the amount of white ink printed, and more than that printed in step525. In step535, a fourth layer of color ink and white ink is printed according to the calculated CMG, and the amount of color ink printed is even more than the amount of white ink printed, as compared to that printed in step530. The process thus continues to step540, where the nth layer of color and white ink may be printed according to the calculated CMG, whereby the ratio of color ink to white ink may continue to increase with each successively printed layer. This exemplary process of printing varied ratios of white to color ink is analogous to the depiction shown, for example, inFIG.4. Alternatively, for the nonlimiting depiction shown, for example, inFIG.5, the ratio of color ink to white ink may be fixed at a predetermined and substantially identical intermediate value for each successively printed layer in steps520,525,530, and535.

In step545, progress of color printing may be evaluated to verify whether the calculated CMG as printed through the nth layer equals the desired color-accurate CMYK color (c). If the number of printed layers of intermixed color and white ink produce a color-accurate desired CMYK color (c), then process500is complete. In step545, if the calculated CMG as printed through the nth layer does not equal the desired color-accurate CMYK color (c), then process500may proceed to step550.

In step550, CMG may be recalculated based on the number of layers already printed in steps520through540, in order to determine the number of additional printed layers that may be necessary to achieve the desired color-accurate CMYK color (c). In step555, the (n+1)th layer of color ink and white ink is printed according to the recalculated CMG, whereby the ratio of color ink to white ink continues to increase. The process thus continues to step560, where the (n+x)th layer of color and white ink is printed according to the recalculated CMG, whereby the ratio of color ink to white ink continues to increase.

In step565, progress of color printing may be reevaluated to verify whether the recalculated CMG as printed through the (n+x)th layer equals the desired color-accurate CMYK color (c). If the number of printed layers of intermixed color and white ink produce a color-accurate desired CMYK color (c), then process500is complete. In step565, if the recalculated CMG as printed through the (n+x)th layer does not equal the desired color-accurate CMYK color (c), then process500may proceed back to step550.

As shown inFIG.11, and consistent with an embodiment, exemplary process600is described for printing color-accurate green color on nonwhite substrates, which begins with step605. Some or all steps in process600may be completed by a footwear, apparel, or equipment manufacturer or proprietor. In other cases, some steps described below may be accomplished by a manufacturer and other steps may be accomplished by another party including another manufacturer, proprietor, retailer, or any other entity. In some cases, one or more of the steps may be optional. In other cases, some steps may be completed in a different order. Still referring toFIG.11, in step605, a desired color-accurate green color (C-green) for printing is selected. C-green may be a color-accurate green that can be printed using the CMYK color model. In step610, four layers of printing are selected for printing the color-accurate C-green.

Still referring toFIG.11, in step615, color management grading for color-accurate green (CM-green) is calculated, using a computer, for printed color and white inks as a function of four layers selected for printing. In process600, CM-green equals C-green. That is, the color to be printed over the selected four layers to achieve CM-green will be indistinguishable by viewing from color-accurate green color (C-green) printed by known techniques. In step615, the calculated CM-green provides that each printed layer comprises a percentage of printed translucent color inks and a percentage of printed opaque white inks, such that the ratio of color ink to white ink in each printed layer varies as a function of the number of layers printed.

In step620, a first layer of ink is printed according to the calculated CM-green, and in this example the first layer of ink printed comprises 90% opaque white ink, 5% translucent cyan ink, and 5% translucent yellow ink. In step625, a second layer of ink is printed according to the calculated CM-green, and in this example the second layer of ink printed comprises 80% opaque white ink, 10% translucent cyan ink, and 10% translucent yellow ink. The amount of color ink printed in the second layer is thus greater than the amount of color ink printed in the first layer. In step630, a third layer of ink is printed according to the calculated CM-green, and in this example the third layer of ink printed comprises 50% opaque white ink, 25% translucent cyan ink, and 25% translucent yellow ink. In step635, a fourth layer of ink is printed according to the calculated CM-green, and in this example the fourth layer of ink printed comprises 20% opaque white ink, 40% translucent cyan ink, and 40% translucent yellow ink. Alternatively, similar to the nonlimiting depiction shown, for example, inFIG.5, the ratio of color ink to white ink may be fixed at a predetermined and substantially identical intermediate value for each successively printed layer in steps620,625,630, and635. For example, each layer of printed ink may alternatively comprise approximately 35% opaque white ink, approximately 32.5% translucent cyan ink, and approximately 32.5% translucent yellow ink, or another desired percentage between that of steps630and635, to achieve the same C-green.

In step640, progress of color printing the color-accurate C-green may be evaluated to verify whether CM-green equals C-green. If CM-green equals C-green, meaning color-accurate green is visible on the printed nonwhite substrate, then process600is complete. In step645, if the calculated CM-green does not equal C-green, then process600may proceed to step645.

In step645, CM-green may be recalculated based on the four layers already printed in steps620through635, in order to determine the number of additional printed layers that may be necessary to achieve the desired color-accurate C-green. In step650, one or more additional layers of color and white ink may be printed according to the recalculated CM-green. The process thus continues to step655, where the progress of color printing may be reevaluated to verify whether the recalculated CM-green equals C-green. If CM-green equals C-green, meaning color-accurate green is visible on the printed nonwhite substrate, then process600is complete. In step655, if the calculated CM-green does not equal C-green, then process600may proceed back to step645.

As shown inFIG.12, and consistent with an embodiment, exemplary process700is described for printing color-accurate pink color on nonwhite substrates, which begins with step705. Some or all steps in process700may be completed by a footwear, apparel, or equipment manufacturer or proprietor. In other cases, some steps described below may be accomplished by a manufacturer and other steps may be accomplished by another party including another manufacturer, proprietor, retailer, or any other entity. In some cases, one or more of the steps may be optional. In other cases, some steps may be completed in a different order. Still referring toFIG.12, in step705, a desired color-accurate pink color for printing is selected for printing over the course of four layers of intermixed translucent color inks and opaque white ink onto a nonwhite substrate. The selected pink color may be a color-accurate pink that can be printed using the CMYK color model.

Still referring toFIG.12, in step710, a first layer of ink is printed comprising 95% opaque white ink and 5% translucent magenta ink. In step715, a second layer of ink is printed comprising 90% opaque white ink and 10% translucent magenta ink. In step720, a third layer of ink is printed comprising 85% opaque white ink and 15% translucent magenta ink. In step725, a fourth layer of ink is printed comprising 80% opaque white ink and 20% translucent magenta ink.

Exemplary process700shown inFIG.12may thus be implemented based on varying percentages of translucent magenta ink and opaque white ink through the course of printing four layers of ink on a nonwhite substrate. Consistent with an embodiment, however, more or less layers of ink may be printed to achieve any desired color-accurate color in the CMYK color model. Alternatively, for example, and similar to the nonlimiting depiction shown inFIG.5, the ratio of color ink to white ink may be fixed at a predetermined and substantially identical intermediate value for each successively printed layer in steps710,715,720, and725. For example, each layer of printed ink may alternatively comprise approximately 82.5% opaque white ink and approximately 17.5% translucent magenta ink to produce a color-accurate pink that can be printed using the CMYK color model.

Referring toFIG.13, a printed surface printed according to one more techniques disclosed herein may be visually inspected or instrument tested and compared against a printed surface printed according to a known technique, when both surfaces are printed onto nonwhite substrates. Consistent with an embodiment, observer805may observe light reflected from multiple printed layers305printed using printer100shown and described with reference toFIG.4. As shown inFIG.4, layers305comprise four layers of printed material310,312,314, and316. As shown inFIG.13, portions of incoming visible spectrum light840may pass through each of the four layers of printed material310,312,314, and316, and reflect back from one or more of these layers back to observer805. This is because each of layers310,312,314, and316comprise an intermixture of translucent cyan ink, translucent yellow ink, and opaque white ink.

Consistent with an embodiment, light840is shown inFIG.13divided into light rays815,820,825, and830. Light ray815may pass through uppermost printed layer316and reflect back through layer316to observer805. Light ray820may pass through printed layers316and314and reflect back through layers314and316to observer805. Light ray825may pass through printed layers316,314, and312and reflect back through layers312,314, and316to observer805. Finally, light ray830may pass through printed layers316,314,312, and310and reflect back through layers310,312,314, and316to observer805.

Because each of layers310,312,314, and316comprise intermixed translucent color and opaque white inks, portions of light840may thus penetrate through all four printed layers, or may penetrate only through one or more printed layers. Thus, observer805will view a combination of light rays840reflected from more than one of layers305to form the observed color-accurate color. As also shown inFIG.13, however, this contrasts with what observer805sees when viewing light850reflected from white layer220printed according to the existing technique shown inFIG.3.

For example, inFIG.13, an observer805may also observe light reflected from printed color layer222of layer205described with reference to known technique200ofFIG.3. As shown inFIG.13, incoming visible spectrum light850may pass through color layer222of layers205, and reflect off of the uppermost surface of white layer220, because color layer222comprises translucent cyan and yellow inks while white layer220(and white layers210through218) comprises opaque ink. That is, as described earlier with reference to the known technique ofFIG.3, observer805will be effectively viewing printed color present only in layer222, because printing of underlying white layers is required by known techniques to create an underlying white substrate for color-accurate printing.

Still referring toFIG.13, and demonstrating the efficacy of the disclosed printing techniques, observer805will nonetheless view each of reflected light850and840and see the same color. In the case ofFIG.13, drawn from the exemplary color printing techniques described with reference toFIG.4and in contrast with the known technique ofFIG.3, observer805will see color-accurate green color when viewing each of reflected light850and reflected light840. That is, printing technique300described inFIG.4will produce color-accurate green color in a manner that is visually and instrument-testing indistinguishable from color-accurate green color printed with existing technique200.

Referring toFIG.14, a printed surface printed according to one more techniques disclosed herein may be visually inspected or instrument tested and compared against a printed surface printed according to a known technique, when both surfaces are printed onto nonwhite substrates. Consistent with an embodiment, observer805may observe light reflected from multiple printed layers307printed using printer100shown and described with reference toFIG.5. As shown inFIG.4, layers307comprise four layers of printed material315. As shown inFIG.14, portions of incoming visible spectrum light940may pass through each of the four layers of printed material315, and reflect back from one or more of these layers back to observer805. This is because each of layers315comprise an intermixture of translucent cyan ink, translucent yellow ink, and opaque white ink.

Consistent with an embodiment, light940is shown inFIG.14divided into light rays915,920,925, and930. Light ray915may pass through uppermost printed layer315and reflect back through layer315to observer805. Light ray920may pass through the first and second printed layers315and reflect back through those layers to observer805. Likewise, light ray925may pass through the first, second, and third printed layers315and reflect back through those layers, as shown, to observer805. Finally, light ray930may pass through the first, second, third, and fourth printed layers and reflect back through those layers, as shown, to observer805.

Because each of the printed layers315forming multiple printed layers307may comprise a predetermined and substantially identical ratio of intermixed translucent color and opaque white inks, as shown inFIG.5, portions of light940may thus penetrate through all four printed layers, or may penetrate only through one or more printed layers. Thus, observer805will view a combination of light rays940reflected from more than one of layers307to form the observed color-accurate color. As also shown inFIG.14, however, and similar to that shown inFIG.13, this contrasts with what observer805sees when viewing light850reflected from white layer220printed according to the existing technique shown inFIG.3. For example, inFIG.14(and similar to what is shown inFIG.13), an observer805may also observe light reflected from printed color layer222of layer205described with reference to known technique200ofFIG.3.

Still referring toFIG.14, and demonstrating the efficacy of the disclosed printing techniques, observer805will nonetheless view each of reflected light850and940and see the same color. That is, for example, each of reflected light850and940will appear as the same color upon visual inspection and instrument testing of the printed layers. In the case ofFIG.14, drawn from the exemplary color printing techniques described with reference toFIG.5and in contrast with the known technique ofFIG.3, observer805will see color-accurate green color when viewing each of reflected light850and reflected light940. That is, printing technique302described inFIG.5will produce color-accurate green color in a manner that is visually and instrument-testing indistinguishable from color-accurate green color printed with existing technique200.

Referring toFIG.15, and consistent with an embodiment, observer805may thus view each of reflected light850,840, and940and see the same color. InFIG.15, drawn from the exemplary color printing techniques described with reference toFIGS.4and5and in contrast with the known technique ofFIG.3, observer805will see color-accurate green color when viewing each of reflected light850, reflected light840, and reflected light940. That is, the printing techniques300and302described with reference toFIGS.4and5will produce color-accurate green color in a manner that is visually and instrument-testing indistinguishable from each other, as well as from the color-accurate green color printed with existing technique200.

Referring toFIG.16, and consistent with an embodiment, further benefits of the disclosed printing techniques will be discussed in the situation where the printed color surface may be scratched, abraded, or otherwise damaged or marred. As shown inFIG.16, a printed surface printed according to one more techniques disclosed herein may be visually inspected and compared against a printed surface printed according to a known technique, when both surfaces are printed onto nonwhite substrates and when both surfaces contain as least one scratch, abrasion, or mar. For example, printed layers305may contain a scratch, abrasion, or mar905, and printed layers205may likewise contain a substantially identical scratch, abrasion, or mar910.

Still referring toFIG.16, and consistent with an embodiment, observer805may observe light reflected from multiple printed layers305printed using printer100shown and described with reference toFIG.4. As shown inFIG.16, portions of incoming visible spectrum light1040may pass through each of the four layers of printed material310,312,314, and316, and reflect back from one or more of these layers back to observer805. This is because each of layers310,312,314, and316comprise an intermixture of translucent cyan ink, translucent yellow ink, and opaque white ink. Light1040may also pass through and be reflected from one or more portions of crack905.

Consistent with an embodiment, light1040is shown inFIG.16divided into light rays1015,1020,1025, and1030. Light ray1015may pass through uppermost printed layer316and portion of crack905therein, and reflect back through layer316to observer805. Light ray1020may pass through printed layers316and314and a portion of crack905therein, and reflect back through layers314and316to observer805. Light ray1025may pass through printed layers316,314, and312, and crack905, and reflect back through layers312,314, and316to observer805. Finally, light ray1030may pass through printed layers316,314,312, and310, and crack905, and reflect back through layers310,312,314, and316to observer805.

Because each of layers310,312,314, and316comprise intermixed translucent color and opaque white inks, portions of light1040may thus penetrate through all four printed layers, or may penetrate only through one or more printed layers, regardless of the presence of crack905. Thus, observer805may view a combination of light rays1040reflected from more than one of layers305as well as from the region exposed by crack905. Thus, when viewing printed layers305comprising crack905, observer805may observe crack905, but crack905may only appear with a slightly lighter color or slightly darker color than the overall color-accurate color printed by layers305. As also shown inFIG.16, however, this contrasts with what observer805sees when viewing light950reflected from white layer220and crack910.

For example, inFIG.16, an observer805may also observe light reflected from printed color layer222of layer205described with reference to known technique200ofFIG.3. As shown inFIG.16, portions of incoming visible spectrum light950may pass through color layer222of layers205, and reflect off of the uppermost surface of white layer220back to observer805. This is because color layer222comprises translucent cyan and yellow inks while white layer220(and white layers210through218) comprises opaque ink. That is, as described earlier with reference toFIG.3, observer805will be effectively viewing printed color present only in layer222, because printing of underlying white layers is required by known techniques to create an underlying white substrate for color-accurate printing. Light950, however, may also pass through and be reflected from one or more portions of crack910.

Still referring toFIG.16, light950may pass through uppermost printed color layer222in the region of crack910, and reflect back from one or more of the underlying white layers220,218, etc. back to observer805. In this case, light950may not pass back through color layer222in the region of crack910. Thus, when viewing printed layers205comprising crack910, observer805may readily observe crack910, as crack910may appear white due to the reflection from one or more underlying white layers220,218, etc., without having passed back through color layer222in the region of crack910. Thus, crack910may appear in high contrast against color layer222upon viewing by observer805.

Referring toFIG.17, and consistent with an embodiment, further benefits of the disclosed printing techniques will be discussed in the situation where the printed color surface may be scratched, abraded, or otherwise damaged or marred. As shown inFIG.17, a printed surface printed according to one more techniques disclosed herein may be visually inspected or instrument tested and compared against a printed surface printed according to a known technique, when both surfaces are printed onto nonwhite substrates and when both surfaces contain as least one scratch, abrasion, or mar. For example, printed layers307, printed as described above with reference to technique302shown inFIG.5, may contain a scratch, abrasion, or mar907, and printed layers205(as similarly shown inFIG.16) may likewise contain a substantially identical scratch, abrasion, or mar910.

Still referring toFIG.17, and consistent with an embodiment, observer805may observe light reflected from multiple printed layers307printed using printer100shown and described with reference toFIG.5. As shown inFIG.17, portions of incoming visible spectrum light1140may pass through each of the four layers315of printed material307, and reflect back from one or more of these layers back to observer805. This is because each of layers315comprise a substantially identical predetermined intermixture of translucent cyan ink, translucent yellow ink, and opaque white ink. Light1140may also pass through and be reflected from one or more portions of crack907.

Consistent with an embodiment, light1140is shown inFIG.17divided into light rays1115,1120,1125, and1130. Light ray1115may pass through uppermost printed layer315and portion of crack907therein, and reflect back through uppermost printed layer315to observer805. Light ray1120may pass through the first and second printed layers315and a portion of crack907therein, and reflect back through these layers to observer805. Light ray1125may pass through the first, second, and third printed layers, and crack907, and reflect back through these layers to observer805. Finally, light ray1130may pass through the first, second, third, and fourth printed layers, and crack907, and reflect back through these layers to observer805.

Because each layer of printed material307may comprise a predetermined and substantially identical ratio of intermixed translucent color and opaque white inks, portions of light1140may thus penetrate through all four printed layers, or may penetrate only through one or more printed layers, regardless of the presence of crack907. Thus, observer805may view a combination of light rays1140reflected from more than one of the layers as well as from the region exposed by crack907. Thus, when viewing the printed layers307comprising crack907, observer805may observe crack907, but crack907may only appear with a slightly lighter color or slightly darker color than the overall color-accurate color printed by the combination of layers307. As also shown inFIG.17, however, and similar to that shown inFIG.16, this contrasts with what observer805sees when viewing light950reflected from white layer220and crack910, where crack910may appear in high contrast against color layer222upon viewing by observer805.

Referring toFIG.18, and consistent with an embodiment, observer805may thus view each of reflected light1040and1140, and see the same color. InFIG.18, drawn from the exemplary color printing techniques described with reference toFIGS.16and17(and in contrast with the known technique ofFIG.3) observer805may see color-accurate green color when viewing each of reflected light1040and reflected light1140. That is, the printing techniques300and302described with reference toFIGS.4and5will produce color-accurate green color in a manner that is visually and instrument-testing indistinguishable from each other, even when one or more of the printed layers may be scratched or otherwise marred by crack905or crack907.

This difference may be exemplified as shown inFIG.19. Referring toFIG.19, and consistent with an embodiment, an athletic shoe, such as soccer shoe1800, may comprise one or more printed regions1805. Printed regions1805may be printed, for example, according to printing techniques discussed herein with reference to any ofFIGS.4-12. In the case of soccer shoe1800, athletic use may impart significant wear-and-tear on the surface finish of the shoe. Such wear-and-tear may take the form of any number of scratches, abrasions, or mars in the finish of printed regions1805. While such damage to the finish of printed regions1805may be undesirable, it may also be unavoidable during the rigors of use demanded of shoe1800. Therefore, it is desirable to minimize the visibility of any such damage during the usable lifetime of shoe1800. Such minimization may be achieved by implementing the printing techniques disclosed herein.

Consistent with an embodiment, and still referring toFIG.19, exemplary wear-and-tear is shown by scratch1810in shoe1000. As shown and described earlier with reference toFIGS.16and17, light rays passing through printed regions1805will not result in a high contrast difference between the printed regions1805and that of scratch1810. As discussed earlier, an observer may view a combination of light rays reflected from more than one of layers of printed regions1805, as well as from the region exposed by crack1810. That is, because the underlying printed layers comprise a mixture of translucent color ink and opaque white ink, color from one or more exposed underlying layers will be visible to an observer when those one or more underlying layers are exposed by crack1810. Thus, when viewing printed region1805and crack1810, crack1810may only appear with a slightly lighter color or slightly darker color than the overall color of printed regions1805. As also shown inFIG.19, however, this contrasts with what may be observed when viewing light reflected similarly from a shoe comprising regions printed according to existing techniques.

Still referring toFIG.19, another exemplary wear-and-tear is also shown by scratch1860in soccer shoe1850. Soccer shoe1850may comprise one or more printed regions1855. Printed regions1855may be printed, for example, according to existing printing techniques discussed earlier with reference toFIG.3. As shown and described earlier with reference toFIG.16, light rays passing through printed regions1855will result in a high contrast difference between the printed regions1855and that of crack1860. As discussed earlier, an observer may view light that has passed through the opening exposed by crack1860and reflected off of one or more of the underlying printed white layers back to the observer. The light, however, may also pass through and be reflected from one or more portions of crack1860. Thus, when viewing printed regions1855and crack1860, crack1860may appear with a high contrast difference against printed regions1855due to the exposure of one or more underlying opaque white layers. As also shown inFIG.19, crack1860may appear as a white mark relative to the balance of printed regions1855.

Consistent with an embodiment, therefore color durability may be achieved with printed colors according to the disclosed techniques. That is, damage due to scratching, abrasion, or otherwise marring a surface printed using disclosed techniques will be less visible upon observation that similar damage inflicted on a surface printing using existing techniques. Color printing according to the disclosed techniques will be more durable and damage less visible.

For example, applying the Stoll abrasion method, the color durability of printed layers printed according to known printing techniques may only achieve approximately 100 to approximately 120 revolutions of a Stoll abrasion disc before the printed color becomes significantly damaged. This is because the existing printing techniques essentially have only one uppermost layer of printed color, layered over several layers of printed white. Any damage to the uppermost color layer will be more readily apparent because underlying white layers may be exposed. Thus, color durability will be low.

In contrast, applying the Stoll abrasion method to printed layers printed according to disclosed embodiments, may achieve approximately 400 to approximately 450 revolutions of a Stoll abrasion disc before the printed color becomes significantly damaged. This is because the disclosed techniques have multiple layers of translucent color printed in combination with opaque white, such that color is printed throughout all of the printed layers. Any damage to the uppermost color layer will be less apparent because underlying printed layers also contain color intermixed with white. Despite the possible exposure of one or more of these underlying layers, less noticeable variations in color may be observed. Thus, color durability will be high.

Also consistent with an embodiment, the disclosed printing techniques are also applicable to hot-melt printing, whereby solids are melted into a viscous fluid and printed, e.g., an opaque polyurethane and at least one translucent pigmented material. For example, abrasion resistance may also be achieved using the disclosed printing techniques in a hot-melt printer, because printing of opaque polyurethane may be combined with translucent pigmented material that would mix together upon printing onto a substrate.

While various embodiments have been described, the description is intended to be exemplary, rather than limiting, and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the disclosure. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the disclosure, and be protected by the following claims.