Scratch resistant inks
View Patent ↗An ink includes a C 10 to C 26 fatty acid and a microcrystalline wax, the ink exhibiting greater scratch resistance than a conventional ink as measured by scratch and fold testing.
1. An ink comprising:
a C 18 fatty acid; and
a microcrystalline wax having a hardness in a range from about 25 dmm to about 30 dmm and a viscosity in a range from about 12 mm 2 /s to about 16 mm 2 /, wherein the microcrystalline wax is presented in an amount of from about 30% to about 45% by weight of the ink,
wherein the ink exhibits a greater scratch resistance than a conventional phase change ink that does not comprise the C 18 fatty acid and microcrystalline wax as measured by scratch and fold testing.
2. The ink of claim 1 , wherein the fatty acid is stearic acid.
3. The ink of claim 1 , wherein the ink has an onset of melting about 10° C. to about 30° C. lower than a conventional phase change ink, as measured on a differential scanning calorimetry (DSC) curve.
4. The ink of claim 2 , wherein the ink has an onset of melting of about 40° C. to about 55° C. on the DSC curve.
5. The ink of claim 1 , wherein the microcrystalline wax has a melting point in a range from about 55° C. to about 75° C.
6. The ink of claim 4 , wherein the microcrystalline wax has a melting point of about 70° C.
7. The ink of claim 1 , wherein the ink is suitable for print on packaging in food freezer temperature applications.
8. The ink of claim 1 , wherein stearic acid is present at about 15% to about 25% by weight of the ink.
9. An ink comprising:
about 15% to about 25% by weight of the ink of stearic acid;
about 30% to about 45% by weight of the ink of a microcrystalline wax having a hardness in a range from about 25 dmm to about 30 dmm and a viscosity in a range from about 12 mm 2 /s to about 16 mm 2 /s; and
an amphiphilic molecule comprising a C 10 -C 26 chain and terminating in a charged group selected from the group consisting of sulfate, sulfonate, sulfinate, and phosphate, wherein the ink has an onset of melting of about 40° C. to about 55° C. on the DSC curve.
10. The ink of claim 9 , wherein the ink has an onset of melting about 10° C. to about 30° C. lower than a conventional phase change ink, as measured on a differential scanning calorimetry (DSC) curve.
11. The ink of claim 9 , wherein the microcrystalline wax has a melting point from about 55° C. to about 75° C.
12. The ink of claim 9 , wherein the microcrystalline wax has a melting point of about 70° C.
13. An ink comprising:
stearic acid;
a microcrystalline wax having a melting point in a range from about 55° C. to about 75° C., a hardness in a range from about 25 dmm to about 30 dmm and a viscosity in a range from about 12 mm 2 /s to about 16 mm 2 /s; and
an amphiphilic molecule comprising a C 10 -C 26 chain and terminating in a charged group selected from the group consisting of sulfate, sulfonate, sulfinate, and phosphate, wherein the ink has an onset of melting of about 40° C. to about 55° C. on the DSC curve.
14. The ink of claim 13 , comprising about 15 to about 25 weight percent stearic acid and about 30 to about 45 weight percent of the microcrystalline wax.
15. The ink of claim 13 , wherein the ink is suitable for use at temperatures of about −5° C. without becoming brittle.
16. The ink of claim 13 , further comprising a fatty amide.
17. The ink of claim 13 , further comprising a colorant.