Use the Excel Export API to Insert Page Breaks in a Worksheet
The following example demonstrates how to insert a page break on a worksheet to start a new page. Page breaks in a worksheet are contained in two separate IXlPageBreaks collections: one for the horizontal (row) page breaks and one for the vertical (column) page breaks. To get access to these collections, use the IXlSheet.RowPageBreaks and IXlSheet.ColumnPageBreaks properties, respectively. To add a new page break, use the IXlPageBreaks.Add method and pass an index of the row or column after which a page break should be inserted. To remove a single page break from a worksheet, use the IXlPageBreaks.Remove or IXlPageBreaks.RemoveAt method. To clear all page breaks at once, use the IXlPageBreaks.Clear method.
// Insert a page break after the column "B".
sheet.ColumnPageBreaks.Add(2);
// Insert a page break after the tenth row.
sheet.RowPageBreaks.Add(10);
The image below illustrates the result (the workbook is opened in Microsoft® Excel®).