is a modified starch that contains positively and negatively charged substituent groups. It is used as wet-end additives, surface sizing agent and coating agent in the paper mill industries
When printing two or more ink colors in line, the ink tack and sequence must be adjusted in order for the inks to adhere to each other as well as to the paper.
Severe cockling (rippling of paper, usually caused by exposure to moisture) or creases may cause aesthetic or structural problems, and the paper in a creased area may weaken or tear if not reinforced. Cockling and other distortions may cause abrasion of the image in areas which rub against another work stacked above or against glazing material in contact with the paper. Wrinkles and creases may be flattened by local application of moisture to that area, followed by gentle pressure under blotters and weights. When necessary, severe creases may be reinforced on the verso with Japanese paper adhered with an archival paste. Overall cockling of the paper (if not inherent to the work) may necessitate relaxation of the paper with moisture, and subsequent pressing between blotters under weight. If the media is too sensitive for this type of flattening procedure, a special matting arrangement (a more deeply cut window mat) might be helpful in protecting the surface.
An organization that coordinates the many different needs of the broad based paper and paper board industry, including statistical information relating to production, consumption, exports and imports of paper and to raw materials energy, governmental regulations, forecasts, environmental matters and transportation.
Term applied to any pulp and paper sample that has a moisture content in equilibrium with the surrounding atmospheric conditions.
The temporal lobe can be divided into two main sections: first, the neocortex, comprising its lateral and inferolateral surfaces, and its standard cerebral cortex; and, second, the mesial temporal lobe, which is sometimes referred to as the limbic lobe, and includes the hippocampus, the amygdala, and the parahippocampal gyrus.
Air-dry pulps are assumed to contain 10% moisture.
A paper manufacturing process in which fibers are carried and formed to the structure of paper by air rather than water as in traditional papermaking.
A paper may become weakened through contact with other acidic materials, through inherent flaws in its manufacture, by previous mishandling causing tears and structural weaknesses, or by previous attachment to a poor quality mount. If the paper is extremely fragile, it may be strengthened by lining (backing) the sheet with a high quality Japanese or rag paper adhered with an archival adhesive. The lined work is then dried under slight tension or between blotters under appropriate weight to avoid any cockling or distortion. In cases where the paper or media should not be flexed at all, mounting to an archival secondary solid support may be considered.
Previously mended tears may stain and distort the paper in the torn area because of badly applied and poor quality adhesives. Old mends should be removed and be replaced with archival repairs. Tears left unrepaired may increase in length, causing more damage as the paper is handled. Lacunae (losses in the paper) which are left unfilled, are subject to the same mechanical stresses as the tears. Tears may be mended with wheat starch paste or methyl cellulose, reinforced with Japanese tissue on the verso as necessary, or with archival heat set tissue. Lacunae may be filled by inserting a patch of paper which is close to the original paper in texture, weight, and color, or with liquid paper pulp. Where the lacunae or tear intrudes into the design, minimal toning of the repair can create a less visually disturbing mend.
Paper exposed to heat and ultraviolet light, that has been in contact with poor quality materials, or that has a high percentage of wood pulp fiber, may become darkened and brittle. Deacidifying solutions can be introduced into a paper by immersion, or by brushing or spraying on the solution. Both aqueous and non-aqueous solutions are available and deposit an alkaline reserve in the paper. This process helps to
Stains such as foxing (brown spots caused by molds or my metal impurities left in the paper during manufacture), matburn (the brown line caused by contact with an acidic mat), some water stains, and mold stains may not be removed by immersion in water. If these stains are very disfiguring, it may be appropriate to use one of a variety of bleaching agents that have been thoroughly tested and researched for use on works of art on paper. Sun/light bleaching, and bleaching with chemicals such as hydrogen peroxide or calcium hypochlorite, are possibilities given certain conditions in the media and the paper. Any bleaching should be carried out in a carefully measured and controlled environment and all necessary precautions taken to be sure that any bleaching agent is neutralized or washed from the paper.
The information on this website is of a technical nature intended for people in the paper making related industries. Often what you are looking for can be more easily obtained with a direct inquiry by using the form at the bottom of the page.