This sheet of IEC 60819-3 specifies requirements for four types of unfilled aramid papers:
Type 1: Calendered paper
Type 2: Calendered paper with improved tearing resistance and conformability
Type 3: Uncalendered paper
Type 4: Calendered paper with lower density for laminating
IEC 60819-3-3:2006 history
2011IEC 60819-3-3:2011 Non-cellulosic papers for electrical purposes - Part 3: Specifications for individual materials - Sheet 3: Unfilled aramid (aromatic polyamide) papers
1970IEC 60819-3-3:2006/COR1:2008 Corrigendum 1 - Non-cellulosic papers for electrical purposes - Part 3: Specifications for individual materials - Sheet 3: Unfilled aramid (aromatic polyamide) papers
2006IEC 60819-3-3:2006 Non-cellulosic papers for electrical purposes - Part 3: Specifications for individual materials - Sheet 3: Unfilled aramid (aromatic polyamide) papers
1991IEC 60819-3-3:1991 Specification for non-cellulosic papers for electrical purposes; part 3: specifications for individual materials; sheet 3: unfilled aramid (aromatic polyamide) papers