Choosing the correct paper is vital if you want high-quality, durable prints of digital photos. The paper must have exactly the right level of absorbency to accept the ink but be able to prevent the ink from spreading. General-purpose office papers are usually too absorbent and can’t reproduce either the fine detail or vibrant colours that characterise good photo prints. Most digital camera users know you must use photo quality paper if you want prints that look and feel like traditional photo prints.
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Choosing the correct paper is vital if you want high-quality, durable prints of digital photos. The paper must have exactly the right level of absorbency to accept the ink but be able to prevent the ink from spreading. General-purpose office papers are usually too absorbent and can’t reproduce either the fine detail or vibrant colours that characterise good photo prints. Most digital camera users know you must use photo quality paper if you want prints that look and feel like traditional photo prints. All inkjet papers have coated surfaces that accept the ink (and it’s important to print on the coated side of the paper). Coatings give papers certain qualities, such as weight, flatness, surface texture and ink absorbency. The three main paper types used for photo inkjet printing are largely defined by their surface coatings: swellable, porous (or microporous) and cotton rag. It’s important to understand the differences between them because some types of paper perform better with certain inks types and different paper types require different handling. Swellable papers should only be used with dye-based inks. Swellable paper has a coating that expands when it comes in contact with ink, allowing the inks to penetrate the top layers.  Most swellable papers consist of five layers: 1. The top layer has a protective coating that expands when it comes in contact with ink and prevents the dyes from spreading. It also excludes atmospheric pollutants. 2. Beneath it is a layer that fixes the ink droplets in place. 3. Below that is a layer that absorbs additional ink components. 4. Like traditional photographic papers, the actual paper base is sandwiched between two polyethylene layers to prevent dyes from penetrating. 5. An anti-curl coating and an anti-static layer is applied to the back of the paper to keep the print flat and repel dust. Porous papers are often referred to as ‘instant dry paper’. They are coated with microscopic inert particles that create cavities in the surface into which ink is deposited. These cavities prevent the ink from spreading and give prints a dry-to-the-touch feel.  Porous paper has a higher resistance to moisture and humidity than swellable paper. However, because prints on porous paper have no protective polymer layer, dye colourants tend to be more susceptible to attack by atmospheric pollutants when prints are made on porous papers. Porous paper is the preferred paper to use with pigment-based inks, which are less affected by atmospheric contaminants than dye-based inks. Pigment-based inks also have much better lightfastness characteristics and ozone resistance on porous papers than dye-based inks. Cotton rag papers are generally used for ‘fine art’ printing because they provide excellent image quality and the longest overall print life on the market. They are best suited to pigment-based inks. Cotton papers are generally acid free and lignin free. Some manufactures add alkaline buffers for increased protection from atmospheric contaminants. Information on the importance of paper profiling can be found in ICC profiles. This is a reliable – and trouble-free – way to be sure you print on high-quality, long-lasting paper.
Glossy or Matte? It can be difficult to select high-performing papers that produce long-lasting prints from the multitude of papers on sale. However, because inkjet papers often perform differently with different inks and printer types, it is best – at least initially – to use the papers and inks recommended by the printer manufacturer. Glossy photo paper has a shiny surface that is smooth to the touch and gives prints a rich appearance with sharp definition and vivid colours. High-gloss (or super-gloss) is even shinier to emphasise these characteristics. Unfortunately, prints on glossy media are vulnerable to fingermarking and may suffer from specular reflections (glare) under directional lighting. 
Glossy paper. 
Matte paper. 
Fine art paper.
Weight and Thickness Photo printing papers should be at least 170 gsm in weight; preferably 190-250 gsm, although some glossy papers are available with 300gsm weight. Paper thickness is usually expressed in with millimetres. The table below provides some equivalents for popular photo papers.
When buying paper the weight rating provides the best guide to how heavy the paper will feel (heavier papers have a higher-quality feel than lighter papers). Thicker papers are also stiffer than thinner papers. Unfortunately, some printers are unable to use heavy papers as their paper feed mechanisms are not robust enough to handle the weight and stiffness of thicker media. Some printers require heavier papers to be fed in through a special chute or slot and most can only accept one sheet of heavy paper at a time. Check your printer’s specifications to find the maximum paper weight it can handle. Be cautious when buying lighter-weight papers, especially if they are very cheap. Thin, lightweight papers may not be totally opaque. This factor is particularly important when selecting double-sided paper for printing photo books as you need to be sure the image printed on the reverse side of the sheet does not show through and affect the picture on the front. Opaque papers are also better for prints that will be framed or put into albums because they prevent backing colours from influencing the appearance of the print.
Brightness and Optical Brighteners Because the natural colour of the materials from which paper is made is not pure white, manufacturers add optical brighteners to coatings to produce papers that look white. A bright white paper will allow the maximum colour gamut and black density of the printed image to be reproduced. However, on the negative side, the chemicals used in the OBAs can affect the integrity and longevity of a fine art print over time because the brightening process relies on fluorescence. Optical brighteners are inherently unstable and as they fluoresce, they break down and their ability to fluoresce deteriorates until, eventually, they will no longer do so. When this happens, the colour of the paper will revert to its normal creamy or yellowish hue. How long this process takes will depend on how much exposure the paper has to UV light and the ambient temperatures the prints are displayed in. The message to photographers is: if you want prints that last a lifetime (or more), print on papers without optical brighteners. The same applies to prints that will be displayed under fluorescent lighting or in direct daylight (both of which have high UV levels). UV-blocking glass can slow down the degradation of optical brighteners but will also reduce the brightening effect. Whether to use inkjet papers with optical brighteners is entirely your decision. Some images look best on a bright, white paper, while others could be subtly improved by printing them on a slightly creamy paper. For many images, there is little difference in the overall look of the print, regardless of which base colour is used. This is particularly true for prints that are displayed in lighting with minimal UV content (such as incandescent lighting). If you like the look of the bright white paper and your prints are not being made for extended display periods, there’s no reason not to use papers with brighteners. And since all leading paper manufacturers both types – and many manufacturers have products with very low brightener levels, it should be relatively easy to find the type of paper you want for different applications.
Other Media It is essential that the printing surface be clean and free of grease and dust. Fabric items should be pre-washed and ironed and then stretched to ensure there are no creases on the area where the transfer will be applied. Printed fabrics should be washed by hand to prolong the life of the picture.  Special transfer paper is available to enable you to print your photos – and text or graphics – on t-shirts and other fabric items.
Identifying the Printing Surface Most photo printing papers have the manufacturer’s name (or some other identifier) printed on the rear surface, making it easy to tell which side to print on. However, many fine art papers – and papers supplied in larger-than-A4 sizes – lack such markings and it can be difficult to identify the printing side. With most matte papers, choosing the whiter side of the paper is a good strategy. For glossy and semi-gloss papers, touch a corner with a slightly moistened finger (NOT wet). The coated surface is more likely to feel slightly sticky than the uncoated one.
Fine Art Papers Most fine art papers are acid- and lignin-free, which means they offer greater longevity than ordinary papers. Many have been produced from ‘rag’ or ‘cotton’ materials and offer greater dimensional stability than standard papers. Some have even been manufactured with baryta surface coatings to replicate the look and feel of traditional photo papers. Canvas and other fabric-based media also belong in the ‘fine art’ category because special care is required when using them. When selecting fine art papers for printing, make sure you match the paper’s surface to the type of photograph you plan to print. Some images – for example, portraits – look best on soft, textured papers with a slightly warm tone. Others, like landscapes, buildings and product photographs, look best on glossy media. Make sure an ICC profile is available for the paper (see ICC profiles for more information) and avoid printing on fine art papers unless your printer supports ICC profiles. Pay strict attention to all handling instructions provided with fine art media. The surfaces of some media are fragile and may be damaged if they come into contact with potentially abrasive surfaces.
How Long Will Your Prints Last? The good news is that most inkjet prints are much more durable than colour photo prints with many lasting more than 100 years. The main factors affecting the stability of inkjet prints are the ink/paper combination and handling and storage conditions after the print has been made. A printer that produces long-lasting prints on one paper may not deliver the prints with the same stability when a different brand of paper is used – even though the two papers look almost identical and both claim high longevity. High quality, acid-free papers are more stable than standard papers, which is why they are used for all archiving and fine-art applications. Pigment inks are also more stable than most dye-based inks. The most common cause of colour changes in inkjet prints is a change in the dye chemistry due to oxidation. Certain paper/ink combinations are highly sensitive to ozone, which is common at low-levels in urban environments and reaches high concentrations around devices like refrigerators and air conditioners. This is why you should never display unprotected inkjet prints on the fridge door. Light can cause differential fading, particularly with magenta dyes. Cyan dyes, on the other hand, are most susceptible to chemical contaminants and, as they fade, prints turn orange. To complicate matters, prints made on some papers can take several days to finally stabilise. This can lead to uncertainty about what the final print colour balance will be.  An original digital image. 
An example of the fading that can occur when a print made with dye inks is displayed on a fridge door for six-to-eight months. Inkjet prints last longest when framed behind glass or encapsulated in plastic (‘laminated’) to protect them against airborne pollutants. This is also a good way to protect traditional photos against light, dust and moisture – as well as airborne fungal spores. Don’t expect them to last as long if you stick them up on the fridge door – or in any other place where they may be exposed to ozone or other atmospheric pollutants.
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