Black and White Curves Backgrounds: Black and White Curves Background for Powerpoint 2011 Black and white background, soft gray curves and gradients. Download high resolution abstract background. background April 24th, 2011 , Posted in Backgrounds Black and white background, soft gray curves and gradients. Download high resolution abstract background. black and white abstract Resolution: 5000x3750px Medium size preview (1280x1024px): Black and white abstract background File format: JPG Color theme: black, white, gray Keywords: wavy effects graphic, blank background for presentations, modern design