Maintain image size for CSS printing

Question

Personal as I do to generate an image that will stay background in a div with a text overlaying it and the time I print it keep its size. Type I have an image generated in Photoshop with the following dimensions: 1024px by 749px with 200 dpis that would give 13x9,5 cms real. Only when I put it in html and ask to print it gets the full width of the page 20cms. I am using the following CSS for this div:

#div{
     width: 1024px;
     height: 749px;
     background: url(cartao.jpg) no-repeat !important;
     margin-bottom: 20px;
}