Radiation imagery chemistry: process – composition – or product th – Imaged product – Structurally defined
Reexamination Certificate
2002-11-20
2004-07-27
Schilling, Richard L. (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Imaged product
Structurally defined
C430S022000, C430S496000, C430S536000, C430S944000, C347S100000, C396S210000, C396S310000, C396S315000
Reexamination Certificate
active
06767677
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to silver halide display elements having printed on the back side a printing ink composition comprising coalesced hydrophobic polymer particles having associated therewith a squarine infrared absorbing dye. It further comprises methods for making said display element.
BACKGROUND OF THE INVENTION
Logos are often printed on objects using dyes for cosmetic purposes or as authentification needs. Marks may be a corporate name or other identifying trademarked symbols. For cosmetic reasons the visible color is chosen with great scrutiny. In fact, the actual color may be the most important element of authentification. A more sophisticated means of making a mark useful for authentification is to make the component that is unique invisible to the naked eye. One such way is to use a dye of very low concentration or even more ideally one which absorbs outside the visible region, preferably in the infrared. In fact, many applications in the art describe the use of infrared dyes for security marking purposes. However, dyes that absorb in the infrared region are generally not stable in solution or in air and are particularly susceptible to light fade. This degradation renders them useless for most applications without the presence of a stabilizer. When a dye is used for security or authentification elements, the degradation of this dye eventually results in the inability to recognize the authentification element.
Additionally, there are several reasons why one might want to apply an infrared dye containing composition to the surface of an element carrying a photographic image. For example, a protective overcoat including the infrared absorbing dye can be applied as a final overcoat to assist in the stabilization of the underlying dye stability in an inkjet print. In another embodiment, information can be encoded using an infrared absorbing ink that is invisible to the naked eye over the surface of a photographic print. The information that is in coated on the surface of the print can be, for example, sound information and the like, for example, in U.S. application Ser. No. 09/223,859 filed Sep. 13, 2000. The sound information can be encoded, for example, using bar coding, or some other form of the digital encoding. The surface of the print can then be “played” using a suitable infrared dye detecting apparatus. In another embodiment a surface may need to be marked for simple detection of such mark by silicon based detectors. Such marks can be used to identify an element for further downstream processing events. The same types of stabilization issues exist for the use of infrared dye compositions on photographic elements.
Dye stabilization is well known in the art. Mitsubishi Kasai (EP 0 483 387 A1) and TDK Corp. (U.S. Pat. No. 4,713,314) describes the use of cyanine dyes combined with metal stabilizers. Nickel formazan dyes have been described by Kodak as stabilizers for infrared dyes (U.S. Pat. No. 5,547,728). Additionally, metal dithiolene dyes alone have been disclosed as useful stable dyes for bar coding applications by Kodak (U.S. Pat. No. 4,753,923).
A further limitation on the use of infrared dyes has been solubility issues. One solution to this problem has been the use of loaded latex particles. Loaded latex particles are known for use in a variety of photographic and non-photographic applications. For example, in U.S. Pat. No. 4,237,194 there is described an antistatic composition that uses a polyaniline salt loaded on a polymer latex particle. Coating of the latex composition, followed by drying and core lessons of the latex, produce a suitable antistatic layer. It is also known to load latex particles with fluorescent labels in immunology research. (See, for example, U.S. Pat. No. 4,259,313). Also, multiple fluorescent dyes can be loaded onto the sarne latex particle to achieve useful results (see, for example, U.S. Pat. Nos. 5,326,692 and 5,919,850). U.S. Pat. No. 5,852,074 discloses the use of latex compositions for inkjet inks. U.S. Pat. Nos. 4,401,787; 4,304,769; and 5,594,047 describe various methods of manufacturing loaded latex compositions and discuss the use of such compositions in photographic elements.
U.S. Pat. No. 6,361,916 B1 describes making latex dispersions of infrared dyes. The latex loading allows dispersion of otherwise aqueous insoluble dyes into aqueous solutions. It also allows more efficient dye stabilization due to increased proximity of dye and a co-loaded stabilizer. It further describes photographic elements where those infrared dispersions were added as an additional layer to the photographic surface of the element.
In the processing of photographic media in, for example, a printer or scanner, knowledge of the type of media being processed is beneficial to optimize the use of the media and to assure that the processing that is performed on the media is consistent with the specific type of media in the processor. There are many methods of detecting media type. Some of these methods require additional manufacturing steps, such as applying a special mark, a bar code, or a notch on the media. This adds to the cost of manufacturing the media and also creates unsightly markings on the media. Further, as noted above, many marking methods utilize dyes which have stability or solubility problems. There is still needed an improved method of marking media for detecting the type of media that is to be utilized in an imaging apparatus such as a printer or a scanner.
SUMMARY OF THE INVENTION
This invention provides a silver halide photographic display element comprising a support, a front side which has at least one silver halide emulsion layer, and a back side, said front and back sides being on opposite sides of the support; wherein said photographic element further comprises printed on the back side a printing ink composition comprising coalesced hydrophobic polymer particles having associated therewith a squarine infrared absorbing dye represented by formula I:
wherein:
R and R′ independently represents an aromatic or a heteroaromatic group such that the resulting dye has an absorption max greater than 800 nm;
X represents an oxygen or nitrogen atom, or a group containing an oxygen or a nitrogen atom as a heteroatom, wherein the group must be attached through the heteroatom;
W is a monovalent counter anion to balance the charge on the dye and m is 0 or 1. It further provides a process for producing a display element having printed on the back side a printing ink composition comprising coalesced hydrophobic polymer particles having associated therewith a squarine infrared absorbing dye represented by formula (I), comprising the steps of:
(1) printing a latex composition having water as a continuous phase and, as the dispersed phase, hydrophobic polymer particles having associated therewith the squarine infrared dye, in a digital pattern to said surface of said display element; and
(2) coalescing said latex.
The latex polymer composition used in this invention provides a number of advantages over the prior art. One advantage is the ability to provide a printing ink composition with high infrared sensitivity. When the ink composition has a colorant highly absorbing in the visible region of the electromagnetic spectrum and a dye that is an infrared absorbing dye, the display elements of this invention also have high sensitivity to optical sensors. The high sensitivity in both the infrared and colored spectrum allows for accurate detection by sensors in the processor, allowing the display elements of the invention to provide “instructions” to the processor. The printing ink composition also increases the stability of the infrared dye. The squarine infrared dye latex composition is a particularly stable dye composition.
DETAILED DESCRIPTION OF THE INVENTION
The inventors herein have found that infrared absorbing dyes can be loaded on latex polymer particles and then dispersed to form printing inks or added to preformed colored printing inks. The infrared dye on the latex, therefore, allows marking of a photog
Eastman Kodak Company
Meeks Roberts Sarah
Schilling Richard L.
LandOfFree
Display element with a backprint comprising a squarine dye does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Display element with a backprint comprising a squarine dye, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Display element with a backprint comprising a squarine dye will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3225659