Tear

1. Decrease starch solids, pick-up, or concentration at size press if other tests permit.
— high internal bond tends to lower tear.
2. Reduce amount of refining if other tests permit.
— bulkier sheets have higher tear resistance.
— high consistency refining tends to help tear.
3. Check that sheet contains sufficient moisture.
— low moisture contributes to low tear.
4. Check that ash content of sheet is not too high.
— reduce ash content if opacity will permit.
5. Investigate possible furnish change to include more high tear pulp.
— usually means longer, thick walled fibers.
— may need to run to maximum basis weight of specification.
6. Reduce usage of wet-end strength additives if tests will permit.
7. Change the sheet formation.
— a wild sheet often has higher tear.
— adjust jet/wire ratio to open up the sheet.
8. Check and adjust calender loading.
— high nip pressure will lower tear.
9. Reduce broke usage (higher fines) that may contribute to lower tear.
10 Slack draws tend to improve tear resistance.