Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B44—DECORATIVE ARTS
  • B44C—PRODUCING DECORATIVE EFFECTS; MOSAICS; TARSIA WORK; PAPERHANGING
  • B44C1/00—Processes, not specifically provided for elsewhere, for producing decorative surface effects
  • B44C1/22—Removing surface-material, e.g. by engraving, by etching
  • B44C1/228—Removing surface-material, e.g. by engraving, by etching by laser radiation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/24—Ablative recording, e.g. by burning marks; Spark recording
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B44—DECORATIVE ARTS
  • B44C—PRODUCING DECORATIVE EFFECTS; MOSAICS; TARSIA WORK; PAPERHANGING
  • B44C3/00—Processes, not specifically provided for elsewhere, for producing ornamental structures
  • B44C3/005—Removing selectively parts of at least the upper layer of a multi-layer article
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
  • B41M5/34—Multicolour thermography

Definitions

• This invention relates to a system and method of incorporating graphic and text elements on a surface of an article, and particularly to such a system and method that incorporates the graphic and text elements via etching of a multi- layered coated surface of the article.
• the marking of products using both graphics and text is a common process employed by almost every manufacturer. This marking is used to provide a user with information related to brand names, product specifications, safety warnings, and much more.
• One common method of marking products is to adhere a pre-printed label having the desired information onto an appropriate surface of the product.
• Another common method involves painting or inking the information onto a surface of the product using a direct printing process, such as screen process printing (often referred to as silk- screening), pad printing, or some form of lithographic printing. While these latter processes for directly printing information on a product vary greatly in their details, all involve the use of a reusable component that contains the graphics and text to be printed on the product.
• screen process printing employs a screen having mesh covered openings in the configuration of the desired graphics and text. The screen is placed on the surface to be printed and paint or ink is forced through the mesh covered openings to form the graphics and text on the article.
• labels can be susceptible to peeling or unauthorized removal.
• both labels and topically applied painted or inked markings are susceptible to damage and wear.
• aligning and placing a label on a product or printing markings on a product can be very labor intensive if done by hand, as is often the case.
• the system and method should produce high resolution, readable graphics and text of very small sizes. And finally, the system and method should allow a user to make changes to the markings almost on a real time basis without the need to scrap old labels and direct printing components, or procure new ones.
• embodiments of the present invention directed to a system and method for incorporating graphic and text elements on a surface of an article by employing an ablative etching device that is capable of etching the elements into a coating on the article's surface having at least two layers of a material such as paint, ink or the like.
• the etching device etches into the coating layers to a depth that removes the material of the outermost, exposed layer, but which leaves intact at least a portion of the depth of an underlying layer.
• the graphics and text take on the color of the particular underlying layer exposed by the etching process.
• the underlying layer has a color that contrasts the color of the outermost, exposed layer because the graphics and text elements become plainly readable against the contrasting background color of the outermost layer.
• the graphics include conventional bar coding
• the contrast provided by the layered coating scheme described above facilitates the accurate scanning of the bar codes.
• the ablative etching device can take the form of any appropriate apparatus that removes material from the coating layers without making actual contact with the layers.
• laser etching devices using a laser beam to etch the coating layers is one possibility.
• particle beam etching devices such as those using molecular, ion, electron, or radical beams to etch materials from a surface, could be employed.
• a laser etching device is preferred as such devices provide the desired etching resolution, are readily available from commercial sources and are the most practical to operate.
• the ablative etching device chosen can employ a variety of different beam configurations
• a pulse-type laser could be employed for this purpose.
• the advantage of forming the graphic and text elements as an array of holes revolves around the ability to etch each of the holes down to a different one of the underlying layers. In this way each of the holes can exhibit a different color.
• three underlying layers could be formed where each is one of three primary colors - e.g. yellow, magenta and cyan.
• the graphic and text elements are a different color. For example, this apparent color would be red if the adjacent holes alternately exhibited yellow and magenta. Similarly, the apparent color would be green if the adjacent holes exhibited yellow and cyan. And finally, the apparent color would be blue if the adjacent holes exhibited magenta and cyan.
• the size and density of the holes has to be controlled. It is believed the apparent colors can be produced by making the holes no larger than about 0.005 of an inch in diameter and grouping them in a density no less than about 90,000 holes per square inch.
• the shade of the apparent color associated with a portion of the graphic and text elements can also be made to appear lighter or darker to a viewer. This is accomplished by employing a white layer to lighten the shade and a black layer to darken the shade.
• the color of a portion of the graphic and text elements is lightened by uniformly intermixing areas exhibiting a white color throughout the array in that portion.
• the color of a portion of the elements can be darkened by uniformly intermixing areas exhibiting a black color throughout the array in the portion.
• these areas of black or white color have a size commensurate with that of the etched holes in the array.
• the shade is varied by varying the density of the black or white areas.
• the black or white areas can be formed in the array in two different ways. One way is to include a black or white layer, or both, as ones of the aforementioned underlying layers. If so, the black or white areas are formed by using the etching device to etches a hole in the coating layers down to the black or white layer, as appropriate. Alternatively, the overlying, exposed layer can be made to be either black or white. If so, the black or white areas, as the case may be, are formed by refraining from etching a hole into the layers at that spot in the array.
• An alternate method of etching the graphic and text elements into the covering layers to produce an apparent color is to completely remove the material of the overlying, exposed layer, as well as any other layer covering the outermost of two prescribed primary color layers to be used in the previously-discussed alternating color pattern.
• an array is formed by etching holes through the exposed primary color layer into the layer associated with the second of the prescribed primary colors. Adjacent array locations are made to alternate between an etched location exhibiting the color of the more underlying prescribed primary color layer and a non-etched location exhibiting the color of the outermost prescribed primary color layer.
• any white layer intended for use in lightening the shade of the apparent color, as well as any black layer intended for use in darkening the apparent color, would be formed underneath the primary color layers and intermixed into the array by etching holes to the appropriate one of the layers.
• the just-described embodiments of the system and method for incorporating graphic and text elements on the surface of an article resolve the problems of peeling, unauthorized removal and wear associated with conventional labels and direct printing techniques.
• the markings are permanently etched into a multi- layered coating covering a surface of the article, thereby resisting removal and tampering.
• the markings are not raised above the outermost, exposed layer, they are less susceptible to damage and wear.
• current ablative etching devices are capable of producing graphics and text having extremely high resolution. This allow the etching of extremely small characters (e.g. character sizes around 0.015 inches tall) which can still be easily read against the contrasting background of the outermost layer.
• FIG. 1 is a cross-sectional view of a back cover of a PC Card incorporating a two-layer version of the coating scheme embodying the present invention prior to the etching of graphic and text elements into the coating scheme.
• FIG. 2A is a view of the exterior of the cover of Fig. 1 subsequent to the etching of lettering into the coating scheme.
• FIG. 2B is a cross-sectional view of the cover of Fig. 2A cut in the lateral direction through a portion of the lettering.
• FIG. 3 is a cross-sectional view of a portion of the back cover of Fig. 1 subsequent to etching that shows three acceptable etch depths on the left and one potentially unacceptable etch depth on the far right.
• FIG. 4 is a cross-sectional view of a portion of a back cover of a PC Card incorporating a five-layer version of the coating scheme embodying the present invention prior to the etching of graphic and text elements into the coating scheme.
• FIG. 5A is an enlarged view of the exterior of the cover of Fig. 4 showing a portion of the graphics and text etched into the coating scheme using an array of holes where adjacent holes in the array are etched to a different depth thereby alternately exhibiting either a yellow or cyan color so as to appear green.
• FIG. 5B is a cross-sectional view of the cover of Fig. 5A cut in the lateral direction through a row of the array of holes.
• FIG. 6 is an enlarged view of the exterior of the portion of the cover of Fig. 5A & 5B where some of the holes have been replaced by uniformly distributed non- etched areas exhibiting a white color, thereby making the apparent color a lighter shade of green.
• FIG. 7 is an enlarged view of the exterior of the portion of the cover of Fig. 5A & 5B where some of the holes exhibiting the colors yellow or cyan have been replaced by uniformly distributed holes exhibiting a black color, thereby making the apparent color a darker shade of green.
• FIG 8 is a cross-sectional view of the cover of Fig 4 showing a portion of the graphics and text etched into the coating scheme where the material of the overlying white and yellow layers is completely removed and an array of holes is etched into the exposed magenta layer to form a pattern alternately exhibiting either magenta or cyan so as to appear blue
• the preferred embodiments of the present invention employ known etching technology and a unique multi-layered surface coating to add graphics and text to an article
• the known etching technology involves apparatuses and methods where an ablative beam is moved in relation to an article so as to etch or engrave marks into its surface
• these etching devices employ one of two general methods to create the desired markings
• the first method is known as a raster scan method
• raster scan etching an ablative beam having a defined beam width is swept horizontally across the surface of the article to be etched
• the beam horizontally scans it is modulated so as to impinge onto the article only in those locations in the scan line that are part of the marking being etched into the surface
• the etching device moves the beam vertically a distance approximately equal to the aforementioned beam width and the scanning and modulating process is repeated
• the horizontal scanning and vertical repositioning steps continue until the desired image is established on the surface of the article.
• the other general category of ablative etching devices operate by moving an ablative beam in relation to the article such that the desired markings are traced out on the article's surface.
• a typical etching device in this category has a computer into which pattern data is input.
• the pattern data comprises one or more set of two dimensional coordinate information that specify the movements of the ablative beam.
• the computer controls an X-Y translation apparatus that moves the beam according to the pattern data and additional information provided by a user via a user interface.
• the depth the ablative beam etches into the surface of the article in either category of etching devices is directly related to the power of the beam and the speed at which the beam is moved relative to the article (i.e. the length of time the beam impinges on a particular spot). Accordingly, the etching depth can be controlled by controlling the power of the beam and/or the speed at which the beam moves relative to the surface being etched.
• a depth control apparatus for this purpose is typically incorporated into current ablative etching devices so as to allow the depth of the etching at any spot on the article's surface to be controlled and specified by the user.
• the ablative etching device can take the form of a laser etcher that uses a laser beam to etch markings into an article. However, it is not intended that the present invention be limited to such laser etching devices. Rather, other types of ablative etching devices can be employed if desired. For example, various particle beam etchers could be used, such as those employing a molecular, ion, electron, or radical beam to etch materials from a surface. While these other ablative etching devices are acceptable, it is noted that a laser etching device is preferred because these devices can provide the desired etching resolution and are readily available from commercial sources. In addition, it is believed laser etching devices are the most practical to operate. The preferred laser etching device will be referred to in connection with the description of the invention in the remainder of this specification for convenience sake. However, it should be understood that any other appropriate ablative etching device could be substituted without departing from the scope of the present invention.
• laser etching processes to mark articles with graphics and text can have a significant advantage over the previously-described labeling and direct printing methods. Since the markings are engraved into the surface of the article, the problems associated with peeling and unauthorized removal of labels is resolved. In addition, as the engravings are not raised above the surface, they are less susceptible to damage and wear. Essentially, it is the un-etched portions of the surface that take the brunt of the wear and tear the article may be subjected to, thereby protecting the actual markings. Further, current laser etching devices are capable of creating extremely high resolution characters. For example, some laser etching devices can create characters having heights of 0.004 inches or less, although for practical purposes (i.e. readability) character heights no less than about 0.015 inches are preferred.
• some current computer- controlled laser etching devices include software that allows a user to input changes into the computer and view the results on a monitor and/or printout before the etching process begins.
• changes can be made, approved and implemented in a matter of hours rather than days or weeks. Accordingly, last minute changes can be implemented quickly, without the inherent scrapping and replacement costs associated with revising labels or direct printing components.
• modifications to the images etched onto an article can be made almost real time, it is feasible to add custom graphics and text to small product runs, thereby making the cost to small customers commensurate with other orders.
• the use of a laser etching device alone to mark a product with desired information is in many cases not feasible. It has been found that the contrast between the etched portion and the non-etched portions of a surface is often not sufficient to facilitate it readability. This contrast problem is particularly troublesome in regards to bar codes etched into a surface. A low contrast between the etched bar codes and the surrounding surface makes it practically impossible to scan the code accurately.
• the back cover is typically used to display the required registration, authorization, and other information. This back cover is typically metal, usually aluminum or stainless steel.
• FIG. 1 illustrates one preferred embodiment of the multi-layered surface coating scheme according to the present invention prior to its being etched. Specifically, a cross-section of the back cover 20 of a PC Card is depicted to serve as an example of how the system is employed on a surface of an article. It is noted, however, that this coating scheme can be used on practically any article, regardless of its shape, construction or the type of material making up the article's surface. Thus, the invention is not limited to just PC Cards.
• the depicted embodiment shows the external surface 22 of the back cover 20 as having a two-layer coating.
• the first, undercoat layer 24 is applied directly to the surface 22, and the second, overcoat layer 26 is applied over the undercoat.
• the undercoat layer 24 can cover the entire external surface of the cover 20, but need only cover the portion of the surface 22 that is going to be used to display the desired graphics and text. This layer 24 is shown as covering only a portion of the external surface 22 in Fig. 1.
• the overcoat layer 26 may just cover the extent of the undercoat layer 24 if desired. However, as shown in Fig. 1 , the overcoat layer 26 can also be extended and employed as an outer coating for the entire back cover 20, as well as the undercoated region.
• Figs. 2A and 2B show the back cover 20 of Fig. 1 after it has been etched.
• Fig. 2A is a top view of the cover 20 onto which the letters "ABC" have been etched as an example.
• Fig. 2B depicts the cross-section of the cover through the etched lettering.
• the portions of the overcoat layer 26 coinciding with the lettering have been removed by one of the laser etching processes described previously, and the undercoat layer 24 has been exposed in those areas.
• the etch should be deep enough to completely remove the overcoat layer 26 in the area of the lettering, but not so deep as to remove all of the undercoat layer 24 in the region thereby exposing the surface 22 of the cover. Referring to Fig.
• the undercoat layer 24 and overcoat layer 26 are differently colored to the extent that the contrast between the colors is sufficient to facilitate the readability of the desired graphics and text, as well as ensuring the scanability of any bar codes etched into cover 20.
• the undercoat layer 24 was white in color and the overcoat layer 26 was dark gray (i.e. Pantone 424). It was found that this color scheme provided the necessary contrast.
• the use of a dark color for the overcoat layer 26 to form the background and a light color for the undercoat layer 24 to form the graphics and text was an aesthetic choice.
• the color scheme could have been reversed such that the background color provided by the overcoat layer 26 would be light, while the color of the graphics and text imparted by the undercoat layer 24 would be dark. The same desired results can be obtained using either color scheme.
• the described embodiments of the invention have involved a two-layer coating system capable of producing graphics and text of one color against a background of another, contrasting color.
• the invention is not limited to just these two-layer embodiments. It is also possible to produce graphics and text having varying colors and shades against a contrasting background color.
• Fig. 4 one version of this multi-color embodiment is accomplished by incorporating a system of five layers over the surface of an article, such as the previously-described back cover of a PC Card.
• the innermost layer 40 which is shown applied directly to the external surface 22 of the back cover 20 of a PC Card, is black.
• the subsequent layers 42, 44, 46, 48 in ascending order are colored cyan, magenta, yellow and white, respectively.
• the white layer 48 forms the outermost layer and consequently provides the background color to which the colors of the graphics and text will contrast.
• the laser etching device is set to etch to a depth which removes the white layer material as well as any colored layer material overlying the desired color.
• the etching depth is set so as to etch through the white, yellow and magenta layers 48, 46, 44 so as to expose the cyan layer 42.
• the etch depth it is permissible for the etch depth to extend into the cyan layer 42, as long as it does not extend all the way through to the black layer 40 in any significant portion of the etched area - except when it is desired to darken the color of the graphics and text as will be discussed later in this description.
• the etch depth can be modified so that various portions of the graphics and text produced by the methods of the present invention have different colors. For example, one portion could be cyan, will other portions can exhibit any of the other layer colors, except the color of the outer, exposed layer (i.e. white in the depicted case).
• any of the coating layers depicted in Fig. 4 can also be changed without significant effect.
• any of the coating layers could act as the outer background layer providing contrast to the colored graphics and text created during the etching process.
• the black and white layers could be switched, thereby providing a dark background to colored or white graphics and text.
• the present invention is not limited to the use of a pulse laser in the laser etching device, the embodiment that will now be described assumes such a pulse laser is employed.
• a pulse laser it is possible to etch discrete holes into the covering layers.
• each hole it is possible for each hole to exhibit a different one of the underlying layer colors.
• This has particular advantage when the color scheme depicted in Fig. 4 is employed because the colors yellow, magenta and cyan represent primary colors that can be used in conjunction with the white and black to produce a wide variety of apparent colors.
• An apparent color refers to the color a viewer would see when the graphics and text are formed using an array of holes exhibiting a mixture of the layer colors.
• the apparent color red can be produced by using holes exhibiting the colors yellow and magenta
• the apparent color green can be produced using holes exhibiting yellow and cyan
• the apparent color blue can be produced using holes exhibiting magenta and cyan.
• the black or white areas can be formed in the array in two different ways. One way is to include a black or white layer, or both, as ones of the aforementioned underlying layers. If so, the black or white areas are formed by using the laser etching device to etches a hole in the coating layers down to the black or white layer, as appropriate. Alternatively, the overlying, exposed layer can be made to be either black or white.
• the black or white areas are formed by refraining from etching a hole into the layers at that spot in the array.
• a black and white layer is desired to enable the graphic and text elements to be either darkened or lightened, respectively
• a layer having the color not used as the outermost, exposed layer is made one of the underlying layers.
• a white "pixel" 58 is created by refraining from etching that spot in the array (as shown in Fig. 6)
• a black "pixel” 60 is created by etching through all the overlying layers 48, 46, 44, 42 to the black layer 40 in that location (as shown in Fig. 7).
• the remaining un-etched areas of the outermost, exposed layer between the etched holes can affect the resulting apparent color imparted to the graphics and text.
• the laser etching device to completely remove the material of the overlying, exposed layer, as well as any other layer covering the outermost of the primary color layers to be used in the previously-described alternating color pattern.
• an array is formed by etching holes through the outermost primary color layer to the layer associated with the second of the primary colors to be combined.
• the apparent color blue can be produced by creating an array exhibiting alternating colors of magenta and cyan.
• the white and yellow layers 48, 46 are removed in an area 62 of the coating scheme where graphics and text are to be incorporated. This completely exposes the magenta layer 44 in this region 62.
• the required alternating pattern of the primary colors magenta and cyan is created by etching holes through the magenta layer 44 into the cyan layer 42 in spots corresponding to alternating locations of an array such as described in conjunction with Fig. 6A.
• the etched locations 64 in the array will exhibit a cyan color
• the non-etched locations 66 will exhibit a magenta color.
• any black layer 40 intended for darkening the shade of the apparent color, as well as any white layer 68 intended for lightening the apparent color, would have to be formed underneath the primary color layers, as shown in Fig. 8. Holes exhibiting the black or white color would be intermixed into the alternating primary color array as described previously by etching to the appropriate layer 40, 68 through the magenta and cyan layers 44, 42.
• the coatings can be made of any materials commonly used for this purpose, such as paint or ink or the like, as long as they are of a type that can be etched quickly and efficiently by the laser etching device.
• Tested embodiments of the present invention were prepared using both paints and inks. The paints were applied via a spray process, whereas the inks were applied using a lithographic process. Both the painted embodiments and the inked embodiments were produced with two-layer coating schemes having layer thicknesses between about 13-15 ⁇ m. This thickness range is considered optimal for implementing the present invention. Layers having substantially larger thicknesses would work, however, the etching process would be slower and the resulting markings would have the look and feel of an engraving -something believed to be aesthetically undesirable.
• layers that are significantly thinner than the aforementioned optimal range may lack the opacity needed to provide a clear contrast to the outermost, exposed layer, or may allow the color of underlying layers to show through. It also becomes more difficult to ensure only the overlying layer material is removed while leaving at least some of the thickness of the underlying layer associated with the desired color intact, when excessively thin layers are employed. While, current laser etching devices provide remarkable precision in the etch depth, there are limits. Thus, the layer thickness should not be made less than the depth accuracy of the laser etching device employed.
• the lithographically-applied ink coating scheme is more preferred as it is possible to better control the uniformity of the layer thicknesses over the entire surface of the article being marked. Maintaining uniformity in the layer thicknesses is important to the successful implementation of the present invention as the etch depths have to be precisely controlled to ensure all the material in overlying layers is completely removed, thereby exposing the layer having the color desired for the graphics and text.
• an exterior layer made of a transparent, protective material would be acceptable.
• a transparent, protective material is commonly used to protect the paint or ink covering a surface.
• the transparent outer coat would protect the underlying colored layers.
• the graphic and text elements can be formed as described previously, with the exception that the laser beam of the laser etcher would also etch through the transparent outer layer during the marking process.
• an primer coat layer under the colored layers is also acceptable.
• Such under coat layers are often used to provide an interface between the surface of an article and paint or ink layers to, for example, improve adhesion or prevent chemical interaction.

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• Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Optics & Photonics (AREA)
• Toxicology (AREA)
• Credit Cards Or The Like (AREA)
• Laminated Bodies (AREA)

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Cited By (33)

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Citations (6)

• 1999
  • 1999-08-31 WO PCT/US1999/020058 patent/WO2001015916A1/en not_active Ceased
  • 1999-08-31 JP JP2001520306A patent/JP2003508260A/ja active Pending
  • 1999-08-31 AU AU57998/99A patent/AU5799899A/en not_active Abandoned

Patent Citations (6)

Non-Patent Citations (1)

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