Color shifting film with a plurality of fluorescent colorants

• US 6,506,480 B2
• Filed: 02/16/2001
• Issued: 01/14/2003
• Est. Priority Date: 02/16/2001
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Jonza, James M., Liu, Yaoqi J.
• Primary Examiner(s): Chen, Vivian
• Application Number:
  US09/785,652
• Publication Number:
  US 20020114929A1
• Time in Patent Office: 697 Days
• Field of Search: 928/195, 928/201, 928/203, 928/204, 928/206, 928/207, 928/212, 928/916, 359/1, 359/2, 359/502, 359/580, 359/589
• US Class Current: 428/201
• CPC Class Codes: G02B 5/223 containing organic substances, e.g. dyes, inks or pigments
• CPC Class Codes: Y10S 428/916 Fraud or tamper detecting
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 428/24851 Intermediate layer is discontinuous or differential
• CPC Class Codes: Y10T 428/24868 Translucent outer layer
• CPC Class Codes: Y10T 428/24876 Intermediate layer contains particulate material [e.g., pigment, etc.]
• CPC Class Codes: Y10T 428/24893 including particulate material
• CPC Class Codes: Y10T 428/24901 including coloring matter
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree

Abstract

Disclosed are articles having a color shifting film and indicia located behind the color shifting film. At least a first and second colored portion are arranged as a foreground and background of the indicia. The first portion includes a first fluorescent colorant and the second portion includes a different second fluorescent colorant. At least one of the colored portions is patterned. Bright fluorescent emission is visible from the different colorants over different angular ranges to produce high contrast reversal or change.

Claims

1. An article, comprising:

a color shifting film; and

an indicia layer disposed behind the color shifting film;

wherein the indicia layer includes at least a first and second colored portion arranged as a foreground and a background of the indicia, the first colored portion comprising a first fluorescent colorant and the second colored portion comprising a second fluorescent colorant different from the first fluorescent colorant.

2. The article of claim 1, wherein the first and second fluorescent colorants have first and second emission bands respectively, and wherein at a first viewing angle the color shifting film substantially blocks transmission of light in the first emission band and substantially transmits light in the second emission band.

3. The article of claim 2, wherein at a second viewing angle the color shifting film substantially transmits light in the first emission band and substantially blocks light in the second emission band.

4. The article of claim 2, wherein at a second viewing angle the color shifting film substantially transmits light in the first and second emission bands.

5. The article of claim 1, wherein at least the first colored portion is printed on the color shifting film.

6. The article of claim 1, wherein at least the second colored portion is printed on the color shifting film.

7. The article of claim 6, wherein the first colored portion is also printed on the color shifting film, and the second colored portion is printed substantially continuously to extend over the first colored portion.

8. The article of claim 1, further comprising an adhesive layer.

9. The article of claim 8, wherein the adhesive layer is disposed to permit attachment of the article to a substrate.

10. The article of claim 8, wherein the adhesive layer comprises one of the first and second colored portions.

11. The article of claim 1, wherein the foreground comprises the first colored portion and the background comprises the second colored portion.

12. The article of claim 1, wherein the background comprises the first colored portion and the foreground comprises the second colored portion.

13. The article of claim 1, wherein the color shifting film is selected from the group consisting of a polarizer and a mirror.

14. The article of claim 1, further comprising a substantially white diffuse surface disposed behind the indicia.

15. The article of claim 1, wherein the first fluorescent colorant has an excitation band, and wherein the color shifting film substantially blocks transmission of light in the excitation band at a first angle and substantially transmits light in the excitation band at a second angle.

16. The article of claim 1, wherein the second fluorescent colorant has an excitation band, and wherein the color shifting film substantially blocks transmission of light in the excitation band at a first angle and substantially transmits light in the excitation band at a second angle.

17. The article of claim 1, further comprising additional indicia formed by at least one element selected from the group consisting of an embossed region of the color shifting film, a holographic element, and printed information.