if(document.images){
	for(var i=1; i<20; i++) {
		preloadImage = new Image();
		preloadImage.src = "img/brands/brand"+i+".gif";
	}
}

function swapbrands(image){
	document.images.brands.src = "img/brands/brand"+image+".gif";
}
function swapbrandsoff(){
	document.images.brands.src = "img/blank.gif";
}