Print a node field in a page.tpl.php

Using field_view_field in page.tpl

<?php
      $background_image = field_view_field('node', $node, 'field_image_divider_background', array('label'=>'hidden','type' => 'image_url', ));
// type refers to the field formatter - image_url from the image_url_formatter madule in this case
// see - https://api.drupal.org/api/drupal/modules%21field%21field.module/function/field_view_field/7.x
    ?>

    <?php if (!empty($background_image)): ?>
    <div style="background-image:url(<?php print render($background_image); ?>)" class="imagebreak imagebreak--screened imagebreak--ctas non-clf" >
      etc...
    </div>
    <?php endif; ?>