เอาเส้น กรอบ ออกจาก phpexcel pdf ครับ

$styleArray = array(
    'font'  => array(
        'size'  => 14,
        'name'  => 'thsarabunnew'  
    ),
    'fill' => array(
       'type' => PHPExcel_Style_Fill::FILL_SOLID,
     //   'color' => array('rgb' => 'CCCCCC')
    ),
    'alignment' => array(
        'horizontal' => PHPExcel_Style_Alignment::HORIZONTAL_CENTER,
        'vertical'   => PHPExcel_Style_Alignment::VERTICAL_CENTER
    ),
    'borders' => array(
        'allborders' => array(
            'style' => PHPExcel_Style_Border::BORDER_NONE,
          
        )
    )

);

$objPHPExcel->getActiveSheet()->setShowGridlines(false);