$re = '/\b(:?\d{2}.*?)(?=\h*:?\d{2})/';
$str = '12:00 NAME HTG DAW SDAWERWF 15:00 NUM LEON PARA 20: PEAX SHU MAN POP';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php