account_interest_line/view/account_invoice.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
  <data>
    <record id="interest_account_invoice_form" model="ir.ui.view">
      <field name="name">account.invoice.form</field>
      <field name="model">account.invoice</field>
      <field name="inherit_id" ref="account.invoice_form"/>
      <field name="arch" type="xml">
        <xpath expr="//field[@name='date_invoice']" position="before">
            <label for="date_invoice" string="Recalcular intereses" />
          <div>
            <field name="date_invoice" class="oe_inline" options="{'no_create': True}"/>
            <button name="update_interest"  states="open"
                    string="Actualizar Interes" class="oe_link"
                    type="object" help="Recalcular intereses"/>
          </div>
            <!-- <label for="date_invoice" string="Eliminar intereses"/>
          <div>
          <field name="date_invoice" class="oe_inline" options="{'no_create': True}"/>
            <button name="delet_interest" type="object"  string="Eliminar Interes" states="open"
                    class="oe_link" attrs="{'invisible': ['|', ('state','!=','open'), ('sent','=',True)]}" groups="base.group_user"/>
          </div> -->
        </xpath>
      </field>
    </record>
    <record id="invoice_interest" model="ir.ui.view">
      <field name="name">account.invoice_interest</field>
      <field name="model">account.invoice</field>
      <field name="inherit_id" ref="account.invoice_form"/>
      <field name="arch" type="xml">
        <notebook>
            <page string="Intereses">
              <button name="actualizarInteres" type="object"  string="Actualizar Linea de Interes"
                      class="oe_link" groups="base.group_user" attrs="{'invisible': ['|', ('state','!=','open'), ('sent','=',True)]}"/>
              <field name="interes_ids" nolabel='1'  attrs="{'invisible': ['|', ('state','!=','open'), ('sent','=',True)]}">
                <tree string="Intereses" editable='bottom' delete='false' create='false'  >
                  <field name="name_product" string="Decripcion" readonly="1"/>
                  <field name="price_subtotal" string="Monto Interes" readonly="1"/>
                  <field name="date" string="Fecha de Creacion" readonly="1"/>
                  <field name="state" string="Estado"/>
                </tree>
              </field>
            </page>
        </notebook>
      </field>
    </record>
  </data>
</openerp>