<form name="payment" action="https://interkassa.com/lib/payment.php" method="post" 
enctype="application/x-www-form-urlencoded" accept-charset="cp1251">
<input type="hidden" name="ik_shop_id" value="<?=$ppu['ik_shop_id']?>">

<input type="hidden" name="ik_payment_amount" value="<?=$summa_v?>">
<input type="hidden" name="ik_payment_id" value="<?=time()?>">
<input type="hidden" name="ik_baggage_fields" value="<?=$_SESSION['ID_P'][1]?>">

<input type="hidden" name="ik_payment_desc" value="Пополнение кошелька">
<input class="submit" type="submit" name="process" value='Пополнить кошелек на сумму <?=$summa_v?>  <?=$rru['cena_valuta']?> через платежный шлюз <?=$kassa?>' >
</form>