Claims
- 1. A printing process comprising the steps of:
- providing a toner including a resin and only one of a pair of a color developer and color former dye, wherein the color developer and color former dye react when mixed to produce a first spectral response;
- applying the toner to at least one first selected area of a substrate to obtain a developed image on the substrate in the at least one first selected area;
- thereafter applying the other of the pair to the toner of the developed image when desired in the at least one first selected area to produce the first spectral response when applied.
- 2. The printing process according to claim 1, wherein the toner is at least quasi-colorless, wherein the step of applying the toner to the at least one selected area produces a latent image and wherein the step of applying the other of the pair produces a visible image.
- 3. The printing process according to claim 1, further comprising applying the toner to the at least one second selected area when the toner is applied to the at least one first selected area and applying the other of the pair to the substrate in the at least one second selected area prior to the step of applying the toner to produce a visible image in the at least one second selected area.
- 4. The printing process according to claim 1, wherein the toner has a first color and is visible when applied to the substrate and wherein the first spectral response varies the color of the toner from the first color to a second color to provide authentication.
- 5. The printing process according to claim 1, wherein the substrate is one of photocopier paper, printer paper and plain paper fax paper.
- 6. The printing process accordingito claim 1, wherein the toner is one of photocopier, printer and fax toner.
Parent Case Info
This application is a divisional of application Ser. No. 07/996,550, filed Dec. 24, 1994, now U.S. Pat. No. 5,424,266 which is a continuation-in-part application of application Ser. No. 07/808/331, filed Dec. 16, 1991 and now abandoned, which is a continuation-in-part application of application Ser. No. 07/685,575, filed Apr. 15, 1991 and now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3840385 |
Yoshida |
Oct 1974 |
|
4869981 |
Wing et al. |
Sep 1989 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
996550 |
Dec 1992 |
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Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
808331 |
Dec 1991 |
|
Parent |
685575 |
Apr 1991 |
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