FIBER TYPE
The modern and prestigious paper mills are able to produce very high quality papers for graphic arts, whatever the origin of the raw material. Cellulose is often extracted from cotton or trees (alpha cellulose) and used as a base in making paper.

During the cellulose extraction process, other substances are extracted together, and one of them is lignin, an unwanted molecule in artistic papers due to its yellowish color and the aging it causes of the paper.

The papers we propose are all devoid of lignin, as it has been removed during the paper manufacturing process. The cheapest papers have only been chemically bleached without removing the lignin, a process that does not last, causing a yellowing of the paper in a short time.

Tree fiber contains considerably more lignin than cotton fiber used for papermaking and must undergo chemical or physical treatment to be removed.

The slightly alkaline pH (pH = 8) protects the papers from certain aggressive gases in the air, from any acids in the paper and from traces of lignin.

Some trees contain less lignin than others and are often appreciated by paper mills, one of them is eucalyptus with its low lignin content in addition to its rapid growth.

The old papers contained acids and lignin and that is why they have come down to us yellowish and damaged.

Despite the fact that manufacturers keep their manufacturing secrets and it is difficult to know more than what they want to tell us, they have managed to manufacture for us, the artists, a varied and wide range of high-quality papers designed to beautify our works and last. in the time.

The best results for durability and permanence of prints are obtained when using papers that do not contain optical brighteners (OBA). Our prints are preserved, depending on the paper used and degree of protection, between 45 years and 300 years. Black and white prints tend to keep longer.

WEIGHT
Art papers are usually thick, strong, pleasant to the touch and more or less textured. These characteristics are in contrast to common photographic paper. For this reason, it is generally recommended not to frame or laminate these high-quality papers.

SURFACE
The impression is the final support of the image, the one that expresses, culminates and captures the vision and work of the photographer.

Each artistic paper is seen, touched and felt, it has its own characteristics and personality, its choice is another stage in the creativity of the artist.

The choice of paper will depend in the first place on the personal preferences and personal touch that the artist wants to give to his photograph. Then, it will depend on several factors, rather technical, such as the type of photography, size of the print, final location of the print (artificial light, light color temperature, amount of light, light direction), treatment final print (laminated, framed, etc).

BRIGHTNESS
Paper gloss is the amount of reflected light and should not be confused with whiteness (paper color).

Depending on the raw material used and its transformation method, we obtain papers with characteristics of whiteness, brightness, contrast and color range.

To obtain better characteristics, in certain papers, OBA (optical brighteners) or Barium Sulfate (Barium Fiber Base papers) are added.

ACID FREE
Our art papers are acid-free to prevent discoloration over time. Moreover, they usually have a pH slightly higher than 7 as an antacid reserve, and it is mandatory to respond to the ISO 9706-1994 and ISO 18916: 2007 standards (ISO 18916 specifies the criteria for the preservation of photographs).

An acid-free art paper is not by itself a quality factor, it must be associated with a quality paper free of lignin and other acid substances, or that could become so over time, as is the case with products based on chlorine (PVC and others).

GAMUT
The gamut or color range is the maximum number of colors that can be printed, and it varies depending on:

From the printer.
Of the inks.
Of the paper.
From the ICC color profile.

The greater the color range, the greater the possibility of obtaining colors that are faithful to the image seen on the screen, especially with the more saturated colors.

DMAX
The properties of the paper vary considerably from one paper to another and it is necessary to analyze them well since they have a direct influence on the final appearance of the prints.

The Dmax represents the deepest black that can be printed, and varies depending on:

From the printer.
Of the inks.
Of the paper.
From ICC color profile or black and white printing mode (ABW-Advanced Black and White, Black Only).

The higher the Dmax, the greater the range of gray available, obtaining more subtle and progressive gradients. The Dmax increases when black and white prints are printed in ABW mode instead of color mode.

The Dmax is one of the most important varieties of the paper, greater in a barium paper than in a matte watercolor paper.

OPTICAL BRIGHTENERS (OBA)
The main function of “optical brighteners” is to increase whiteness, brightness, contrast, and color gamut.

To benefit from these advantages, the prints should be exposed to natural or artificial light that radiates ultraviolet (6 to 7% of the total light is enough to activate the OBAs), since the OBAs are fluorescent, they absorb invisible ultraviolet light to us and emit part of it in the visible spectrum, generally in the blues.

If their presence is habitual and desired in many of the papers and cases, they also have the disadvantage that they age poorly, losing their properties. The original white of the paper tends to fade and the colors lose in fidelity.

If you need a durable and stable print that will retain its original appearance for several generations, it is best to select OBA-free paper or frame your prints with museum-style, anti-reflective, UV-protected glass. (These crystals usually filter 80% of the U.V. which is ideal to protect the works without subtracting the qualities of the OBA).

Barium papers have the advantage that they contain less OBA than other lower quality gloss papers.

Those containing OBA appear blue in color and glow brightly.

Papers that do not contain OBA do not fluoresce and do not light up, so they appear brown, dark, as if they were in the dark.

We can also determine, yes, somewhat empirically, the amounts of OBA contained in the papers.

Of the four papers examined here, the one that contains the least OBA is Alpha, followed by Museum, Portrait white and Gloss 271. These visual results agree with the manufacturer’s technical data sheet and the ICC color profiles made.

We can also use this technique to determine whether or not the glass used for framing protects the prints from ultraviolet rays.