Method for photo-curing polymerizable compositions with pulsed light

• US 20060183811A1
• Filed: 02/11/2005
• Published: 08/17/2006
• Est. Priority Date: 02/11/2005
• Status: Active Grant

• Current Assignee: Photonic Curing, LLC (IPValuation Partners, LLC)
• Original Assignee: New Photonics, LLC
• Inventors: Melikechi, Noureddine, Pandher, Ranjit S.
• Granted Patent: US 7,407,616 B2
• Time in Patent Office: Days
• US Class Current: 522/2
• CPC Class Codes: A61C 19/003 Apparatus for curing resins by radiation

Abstract

A method for curing polymerizable compositions by irradiating the compositions with a pulsed light that is emitted from an LED. The method of the present invention is especially suitable for curing dental compositions.

Claims

1. A method for curing polymerizable compositions with a pulsed beam of light said method comprising the step of:

irradiating the polymerizable composition with a beam of pulsed light emitted by at least one LED, wherein said pulsed light has a pulse duration of between about 0.05 to about 75 μ

s and a pulse repetition interval of about 0.25 to about 100 μ

s.

2. The method of claim 1, wherein the cured composition has a higher hardness value than a like composition cured with a continuous wave light source with a like emission spectrum and for like total exposure.

3. The method in claim 2, wherein the cured composition has a characteristic hardness of at least about 40 on the Barber-Coleman Hardness scale when cured at a power level of 20 mW and a cure duration of 20 seconds.

4. The method in claim 2, wherein the cured composition has a characteristic hardness of at least about 50 on the Barber-Coleman Hardness scale when cured at a power level of 20 mW and a cure duration of 20 seconds.

5. The method of claim 1, wherein said LED irradiates less total exposure than is required for a continuous wave light source with a like emission spectrum to cure a like composition to a like depth of cure.

6. The method of claim 1 wherein said polymerizable composition is a photo-curable dental composition.

7. The method of claim 1, wherein said polymerizable composition comprises liquid acrylic monomers.

8. The method of claim 1, wherein said polymerizable composition comprises camphorquinone as a photoinitiator.

9. The method of claim 1, wherein said polymerizable composition comprises a photoinitiator and wherein said LED emits light that has an excitation peak that falls within about 40 nm of the absorption peak of a said photoinitiator.

10. The method of claim 1, wherein said LED emits blue light.

11. The method of claim 1, wherein, said LED emits light with an excitation peak that falls within the range of 440 to 500 nm on the electromagnetic spectrum.

12. The method of claim 1, wherein said pulse duration is from about 0.1 to about 10 μ

s.

13. The method of claim 1, wherein said pulse duration is from about 2 to about 3 μ

s.

14. The method of claim 1, wherein said pulse repetition interval is between about 1 to about 1 μ

s.

15. The method of claim 1, wherein the pulse repetition interval is from about 2 to about 5 μ

s.

16. The method of claim 1, wherein said pulse duration and said pulse repetition interval are selected such that the pulse operates with a duty cycle of from about 5 to about 50%.

17. The method according to claim 1, wherein the cured composition has a cure depth of at least about 2.8 mm.

18. The method according to claim 1, wherein the cured composition has a cure depth of at least about 3 mm.