PatternStyle:
| "none"
| "solid"
| "mediumGray"
| "darkGray"
| "lightGray"
| "darkHorizontal"
| "darkVertical"
| "darkDown"
| "darkUp"
| "darkGrid"
| "darkTrellis"
| "lightHorizontal"
| "lightVertical"
| "lightDown"
| "lightUp"
| "lightGrid"
| "lightTrellis"
| "gray125"
| "gray0625"
The style of fill pattern used for a cell background. If the worksheets zoom factor is changed the pixel scale of the pattern is still expected to stay the same.