Translucent seal cap

• US 9,650,150 B2
• Filed: 04/15/2014
• Issued: 05/16/2017
• Est. Priority Date: 04/15/2013
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Zook, Jonathan D., Ye, Sheng, Wright, Robin E., Hebert, Larry S., DeMoss, Susan E., Swan, Michael D.
• Primary Examiner(s): DELISLE, ROBERTA S
• Application Number:
  US14/783,913
• Publication Number:
  US 20160068274A1
• Time in Patent Office: 1,127 Days
• Field of Search: 4113725-3726, 411373, 411377
• CPC Class Codes: B64D 37/02 Tanks tanks constructed integrally with aircraft wings B64C; shape or construction of tanks per se B65D
• CPC Class Codes: B64D 37/06 Constructional adaptations thereof
• CPC Class Codes: B64D 45/02 Lightning protectors; Static dischargers in general H01T
• CPC Class Codes: F16B 33/00 Features common to bolt and nut
• CPC Class Codes: F16B 33/004 Sealing; Insulation by means of washers F16B43/001
• CPC Class Codes: F16B 37/14 Cap nuts; Nut caps or bolt caps

Abstract

The present disclosure provides methods and articles useful in sealing fasteners, including seal caps and in particular translucent or transparent seals or seal caps. In some embodiments, a seal cap which is optically translucent and optionally visibly transparent contains an uncured sealant, which is optionally optically translucent or visibly transparent, and is applied to a fastener. In some embodiments, the sealant is cured by application of actinic radiation to the sealant through the seal cap. In another aspect, a protected fastener construction is provided comprising: q) a fastener; r) a seal cap; and s) a cured sealant; wherein the sealant is optically translucent and optionally visibly transparent.

Claims

1. A method of protecting a fastener comprising the steps of:

a) providing a fastener;

b) providing a seal cap which defines an interior, wherein the seal cap is optically translucent;

c) applying an uncured sealant to the interior of the seal cap or to the fastener or to both;

d) positioning the seal cap over the fastener such that at least a portion of the fastener resides in the interior of the seal cap; and

e) curing the sealant by application of actinic radiation to the sealant through the seal cap.

2. The method according to claim 1 wherein the fastener protrudes from a first surface of a substrate article and wherein, following steps c), d) and e), every portion of the fastener which protrudes from the first surface of the substrate article is covered by cured sealant or seal cap or both.

3. The method according to claim 1 wherein application of actinic radiation causes the sealant to be substantially fully cured in less than 60 seconds.

4. A method of protecting a fastener comprising the steps of:

f) providing a fastener;

g) providing a seal cap which defines an interior, wherein the seal cap is optically translucent, and wherein the interior of the seal cap contains a quantity of an uncured sealant;

h) positioning the seal cap over the fastener such that at least a portion of the fastener resides in the interior of the seal cap; and

j) curing the sealant by application of actinic radiation to the sealant through the seal cap.

5. The method according to claim 4 wherein the seal cap and uncured sealant recited in step g) are at a temperature of less than 5°

C., and wherein the method additionally comprises the step of;

i) warming the seal cap and uncured sealant to a temperature of at least 20°

C.

6. The method according to claim 5 wherein the fastener protrudes from a first surface of a substrate article and wherein, following step j), every portion of the fastener which protrudes from the first surface of the substrate article is covered by cured sealant or seal cap or both.

7. The method according to claim 5 wherein the seal cap is visibly transparent.

8. The method according to claim 4 wherein the seal cap comprises a polyurethane polymer.

9. The method according to claim 4 wherein the seal cap comprises a polythioether polymer.

10. The method according to claim 4 wherein the seal cap comprises a THV polymer.

11. The method according to claim 4 wherein the seal cap comprises a mixture of a polymer and a nanoparticulate curative.

12. The method according to claim 4 wherein the seal cap and sealant comprise different materials.

13. The method according to claim 4 wherein application of actinic radiation causes the sealant to be substantially fully cured in less than 60 seconds.

14. A method of protecting a fastener comprising the steps of:

k) providing a fastener;

l) providing a seal cap mold which defines an interior;

m) applying an uncured sealant to the interior of the seal cap mold or to the fastener or to both, wherein the uncured sealant is translucent;

n) positioning the seal cap mold over the fastener such that at least a portion of the fastener resides in the interior of the seal cap mold; and

o) curing the sealant by application of actinic radiation to the sealant through the seal cap mold.

15. The method according to claim 14 wherein the fastener protrudes from a first surface of a substrate article and wherein, following steps m), n) and o), every portion of the fastener which protrudes from the first surface of the substrate article is covered by sealant.

16. The method according to claim 14 wherein the uncured sealant is translucent.

17. The method according to claim 14 wherein the uncured sealant is visibly transparent.

18. The method according to claim 14 wherein the uncured sealant cures to form a material that is translucent.

19. The method according to claim 14 wherein the uncured sealant cures to form a material that is visibly transparent.

20. The method according to claim 14 wherein the sealant comprises a polyurethane polymer.

21. The method according to claim 14 wherein the sealant comprises a polythioether polymer.

22. The method according to claim 14 wherein the sealant comprises a mixture of a polymer and a nanoparticulate curative.