We recommend mats only for pictures of the 19th century since this framing technique was invented at this period.
Mats are not adaptable to prints on canvas, only for prints on paper.
Mats of Art-Prints-On-Demand.com
The carton boards acid free and pH neutral. They are characterized by a strong resistance to light according to the DIN 6738 standard.
Mats and glazing If your order a framing with mats, your print will be protected by an acrylic glass. It is necessary to protect the mat and the picture from the impact of the environment.