Porous chemical indicator for gaseous media

• US 9,134,251 B2
• Filed: 09/15/2011
• Issued: 09/15/2015
• Est. Priority Date: 09/23/2010
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Thomas, J. Christopher, Rakow, Neal A., Fansler, Duane D.
• Primary Examiner(s): WHITE, DENNIS MICHAEL
• Application Number:
  US13/816,510
• Publication Number:
  US 20130189166A1
• Time in Patent Office: 1,461 Days
• Field of Search: 422/83, 422/84, 422/85, 422/86, 422/87
• US Class Current: 1/1
• CPC Class Codes: A61B 10/0045 Devices for taking samples of body liquids devices for taking blood samples A61B5/15
• CPC Class Codes: A61B 17/083 Clips, e.g. resilient
• CPC Class Codes: A61B 17/085 with adhesive layer
• CPC Class Codes: B01L 2200/16 Reagents, handling or storing thereof
• CPC Class Codes: B01L 2300/044 pierceable, e.g. films, membranes
• CPC Class Codes: B01L 2300/046 Function or devices integrated in the closure
• CPC Class Codes: G01N 2001/028 Sampling from a surface, swabbing, vaporising
• CPC Class Codes: G01N 2021/773 Porous polymer jacket; Polymer matrix with indicator
• CPC Class Codes: G01N 2021/7796 Special mountings, packaging of indicators
• CPC Class Codes: G01N 2035/00108 Test strips, e.g. paper
• CPC Class Codes: G01N 2035/00148 Test cards, e.g. Biomerieux or McDonnel multiwell test cards
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: G01N 21/783 for analysing gases
• CPC Class Codes: G01N 31/22 using chemical indicators G01N31/02 takes precedence
• CPC Class Codes: G01N 31/221 for investigating pH value
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

Chemical indicators for acidic or basic gases include an inert, porous substrate, an indicator dye or mixture of dyes contained within at least some of the pores of the inert, porous substrate, and an inert adhesive layer attached to the inert, porous substrate. The porous substrate may be a microporous substrate.

Claims

1. A chemical indicator comprising:

an inert, porous substrate;

an indicator dye or mixture of dyes contained within at least some of the pores of the inert, porous substrate, wherein the indicator dye or mixture of dyes is coated on the inert, porous substrate dissolved in a solvent and dried to remove the solvent, wherein the solvent consists of methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, ethyl acetate, ethyl ether, tetrahydrofuran, or dichloromethane; and

an inert pressure sensitive adhesive layer attached to the inert, porous substrate.

2. The chemical indicator of claim 1, wherein the inert, porous substrate comprises a microporous substrate, wherein substantially all of the pores are less than 1,000 micrometers in diameter.

3. The chemical indicator of claim 1, wherein the inert, porous substrate comprises a polymeric porous substrate.

4. The chemical indicator of claim 3, wherein the polymeric porous substrate comprises polyethylene, polypropylene or other hydrocarbon polymer or mixture thereof.

5. The chemical indicator of claim 1, wherein the inert, porous substrate comprises a membrane prepared by thermally induced phase separation.

6. The chemical indicator of claim 1, wherein the indicator dye comprises an acid indicator dye, or a base indicator dye.

7. The chemical indicator of claim 1, wherein the inert pressure sensitive adhesive layer comprises an adhesive layer substantially free of acid-containing and base-containing units.

8. The chemical indicator of claim 1, wherein the inert pressure sensitive adhesive layer comprises a natural rubber adhesive, a synthetic rubber adhesive, a poly-alpha-olefin adhesive, a styrene block copolymer adhesive, a poly-(meth)acrylate adhesive, a silicone adhesive or mixtures thereof.

9. The chemical indicator of claim 1, further comprising a non-porous layer attached to the inert porous substrate by an adhesive layer.

10. A device comprising:

a case; and

at least one chemical indicator within the case, the chemical indicator comprising;

an inert, porous substrate; and

an indicator dye or mixture of dyes contained within at least some of the pores of the inert, porous substrate, wherein the indicator dye or mixture of dyes is coated on the inert, porous substrate dissolved in a solvent and dried to remove the solvent, wherein the solvent consists of methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, ethyl acetate, ethyl ether, tetrahydrofuran, or dichloromethane; and

an inert pressure sensitive adhesive layer attached to the inert, porous substrate.

11. The device of claim 10, wherein the pressure sensitive adhesive layer attaches the chemical indicator to the surface of the case.

12. The device of claim 10, wherein the inert, porous substrate comprises a microporous substrate, wherein substantially all of the pores are less than 1,000 micrometers in diameter.

13. The device of claim 10, wherein the indicator dye comprises an acid indicator dye or a base indicator dye.

14. The device of claim 10, further comprising additional chemical indicators, wherein the additional chemical indicators may be the same or different from the at least one chemical indicator.

15. The device of claim 10, wherein the case comprises a respirator cartridge.

16. The device of claim 10, further comprising a non-porous layer attached to the inert porous substrate by the inert pressure sensitive adhesive layer.

17. The device of claim 16, further comprising a second adhesive layer attached to the non-porous layer.

18. The device of claim 10, wherein the inert pressure sensitive adhesive layer comprises a transparent pressure sensitive adhesive layer.

19. A method of preparing a chemical indicator comprising:

providing an inert, porous substrate;

providing an indicator dye solution;

applying the indicator dye solution to the inert, porous substrate such that at least some of the indicator dye mixture enters the pores of the inert, porous substrate;

drying the inert, porous substrate to remove the solvent, wherein the solvent consists of methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, ethyl acetate, ethyl ether, tetrahydrofuran, or dichloromethane; and

applying a layer of inert pressure sensitive adhesive to the porous substrate.

20. The method of claim 19, wherein applying a layer of inert pressure sensitive adhesive to the porous substrate comprises laminating an inert pressure sensitive adhesive layer to the porous substrate.