Desiccant composition

• US 20020014305A1
• Filed: 04/16/2001
• Published: 02/07/2002
• Est. Priority Date: 09/19/1996
• Status: Active Grant

• Current Assignee: Sud-Chemie Incorporated (Clariant AG)
• Original Assignee: Sud-Chemie Incorporated (Clariant AG)
• Inventors: Robertson, Andrew J., Dick, Stefan O., Shelley, Richard M., Benavides, Julian
• Granted Patent: US 6,689,197 B2
• Time in Patent Office: Days
• US Class Current: 156/308.4
• CPC Class Codes: B01D 53/28 Selection of materials for use as drying agents
• CPC Class Codes: B01J 20/0244 Compounds of Zn
• CPC Class Codes: B01J 20/0277 Carbonates of compounds other than those provided for in B01J20/043
• CPC Class Codes: B01J 20/0281 Sulfates of compounds other than those provided for in B01J20/045
• CPC Class Codes: B01J 20/0288 Halides of compounds other than those provided for in B01J20/046
• CPC Class Codes: B01J 20/0296 Nitrates of compounds other than those provided for in B01J20/04
• CPC Class Codes: B01J 20/045 containing sulfur, e.g. sulfates, thiosulfates, gypsum
• CPC Class Codes: B01J 20/046 containing halogens, e.g. halides
• CPC Class Codes: B01J 20/24 Naturally occurring macromolecular compounds, e.g. humic acids or their derivatives
• CPC Class Codes: B01J 2220/46 Materials comprising a mixture of inorganic and organic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: B01J 2220/4825 Polysaccharides or cellulose materials, e.g. starch, chitin, sawdust, wood, straw, cotton
• CPC Class Codes: B32B 1/00 Layered products having a non-planar shape
• CPC Class Codes: B65D 81/264 for absorbing liquids
• CPC Class Codes: B65D 81/268 the absorber being enclosed in a small pack, e.g. bag, included in the package
• CPC Class Codes: Y02W 90/10 Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics

Abstract

A desiccant composition containing a deliquescent salt and a modified starch containing from about 5 to about 95 percent of the deliquescent salt and from about 5 to about 95 percent of the modified starch.

Claims

1. A desiccant composition comprising a deliquescent salt and a modified starch, wherein the deliquescent salt comprises at least about 5 to about 95 percent of the composition by weight and the modified starch from about 5 to about 95 percent of the composition.

2. The desiccant composition of claim 1 wherein the deliquescent salt comprises from about 20 to about 95 percent of the composition by weight and the modified starch from about 5 to about 80 percent of the composition by weight.

3. The desiccant composition of claim 1 wherein the deliquescent salt comprises from about 50 to about 80 percent of the composition by weight and the modified starch from about 20 to about 50 percent of the composition by weight.

4. The desiccant composition of claim 1 wherein the modified starch comprises a modified corn starch.

5. The desiccant composition of claim 1 wherein the deliquescent salt is selected from the group consisting of alkali, ammonium, alkali earth, earth and transition metal halides, sulfates, sulfites, thiosulfates, nitrates, nitrites, phosphates, carbonates and carboxylates.

6. The desiccant composition of claim 1 wherein the deliquescent salt is selected from the group consisting of LiCl, LiBr, LiI, ZnCl₂, ZnBr₂, LiI, Ca(NO₃)₂*2H₂O, NaHSO₄, Mg(NO₃)*6H₂O, KI, NaI, NaNO₂, KBr, (NH₄)₂SO₄, Na(C₃H₃O₂)*3H₂O, Na₂S₂O₃, NH₄Cl, KHSO₄, Na₂CO₃*10H₂O, ZnSO₄*7H₂O, K₂HPO₄, Na₂SO₃*7H₂O, NaF, K₂(CO₃)₂*2H₂O, Zn(NO₃)₂, NH₄H₂PO₄ and MgCl₂.

7. The desiccant composition of claim 1 wherein the deliquescent salt comprises magnesium chloride.

8. The desiccant composition of claim 1 wherein the deliquescent salt is selected from the group consisting of zinc chloride and lithium chloride.

9. The desiccant composition of claim 1 wherein the deliquescent salt is selected from the group consisting of ammonium chloride, ammonium sulfate and ammonium carbonate.

10. A desiccant composition for application under conditions where the relative humidity is less than about 20 percent comprising a deliquescent salt selected from the group consisting of ZnCl₂, LiCl, ZnBr₂, LiBr, ZnI₂, LiI and a modified starch, wherein the deliquescent salt comprises at least about 5 to about 95 percent of the composition and the modified starch comprises from about 5 to about 95 percent of the composition.

11. The desiccant composition of claim 10 wherein the deliquescent salt is selected from the group consisting of zinc chloride and lithium chloride.

13. The desiccant composition of claim 12 wherein the deliquescent salt comprises magnesium chloride.

14. The desiccant composition of claim 12 wherein the deliquescent salt is selected from the group consisting of NH₄Cl, (NH₄)₂SO₄ and (NH₄)₂CO₃.

16. The desiccant composition of claim 15, wherein the deliquescent salt is selected from the group consisting of calcium chloride and magnesium chloride.

18. The desiccant container of claim 17 wherein the deliquescent salt comprises from about 20 to about 95 percent of the desiccant composition by weight and the modified starch from about 5 to about 80 percent of the composition by weight.

19. The desiccant container of claim 17 wherein the deliquescent salt comprises from about 50 to about 80 percent of the desiccant composition by weight and the modified starch from about 20 to about 50 percent of the composition by weight.

20. The desiccant composition of claim 17 wherein the deliquescent salt comprises magnesium chloride.

21. The desiccant composition of claim 17 wherein the deliquescent salt is selected from the group consisting of zinc chloride and lithium chloride.

22. The desiccant composition of claim 17 wherein the deliquescent salt is selected from the group consisting of ammonium chloride, ammonium sulfate and ammonium carbonate.

24. The process of claim 23 wherein the deliquescent salt comprises magnesium chloride.

25. The desiccant composition of claim 23 wherein the deliquescent salt is selected from the group consisting of zinc chloride and lithium chloride.

26. The desiccant composition of claim 23 wherein the deliquescent salt is selected from the group consisting of ammonium chloride, ammonium sulfate and ammonium carbonate.

12. A desiccant composition for application under conditions where the relative humidity is greater than about 20 percent, comprising a deliquescent salt selected from the group consisting of Ca(NO₃)₂*2H₂O, NaHSO₄, Mg(NO₃)*6H₂O, KI, NaI, NaNO₂, KBr, (NH₄)₂SO₄, Na(C₃H₃O₂)*3H₂O, Na₂S₂O₃, NH₄Cl, KHSO₄, Na₂CO₃*10H₂O, ZnSO₄*7H₂O, K₂HPO₄, Na₂SO₃*7H₂O, NaF, K₂(CO₃)₂*2H₂O, ZN(NO₃)₂, NH₄H₂PO₄ and MgCl₂ and a modified starch, wherein the deliquescent salt comprises at least about 5 to about 95 percent of the composition and the modified starch comprises from about 5 to about 95 percent of the composition.

15. A desiccant composition for application under conditions where the relative humidity is greater than about 50 percent, comprising a deliquescent salt selected from the group consisting of calcium chloride, magnesium chloride, potassium chloride and zinc nitrate and a modified starch, wherein the deliquescent salt comprises at least about 5 to about 95 percent of the composition and the modified starch comprises from about 5 to about 95 percent of the composition.

17. A desiccant container comprising a desiccant composition secured within a water vapor permeable film product, wherein the desiccant composition comprises a deliquescent salt and a modified starch, wherein the deliquescent salt comprises at least about 5 to 95 percent of the composition by weight and the modified starch from about 5 to 95 percent of the composition by weight.

23. A process for manufacturing a desiccant container comprising

(a) preparing a water vapor permeable film product,

(b) preparing a desiccant composition wherein the desiccant composition comprises a deliquescent salt and a modified starch wherein the deliquescent salt comprises at least about 5 to 95 percent of the composition by weight and the starch from about 5 to about 95 percent of the composition by weight,

(c) placing the desiccant composition between layers of the water vapor permeable film product, and

(d) sealing edges of the water vapor permeable film product around the desiccant composition to produce the desiccant container.