ASTM D7805-13(R2021) pdf free download

ASTM D7805-13(R2021) pdf free download.Standard Terminology for Printing Ink Vehicles and Related Materials
4. Terminology
acid number (value), n—an indication of the relative amount of –COOH functionality of a polymer or other molecule. D ISCUSSION —Acid number calculated by the number ofmilligrams of potassium hydroxide neutralized by the free acids present in 1 g ofresin or other material. The determination is made by titrating the sample with KOH in alcohol using phenolphthalein as an indicator. acrylates, n—chemical materials which contain the grouping OCOCHCH 2 , usually in the form ofmonomers or oligomers. acrylic resins, n—thermoplastic or thermosetting polymers or copolymers derived from ethenylically unsaturated mono- mers such as styrene, acrylic/methacrylic acid, and acrylic/ methacrylic acid esters. D ISCUSSION —Acrylic resins are used most commonly in liquid (for example, flexo and gravure) inks. Most waterbased inks are formulated from acrylic resins or acrylic emulsions. adhesion, n—state in which two surfaces are held together by interfacial forces that may consist of valence forces, inter- locking action, or both. alkyd, n—synthetic resins formed by the reaction of polybasic acids with polyhydric alcohols, typically modified with unsaturated vegetable oils. D ISCUSSION —Alkyds are typically used in oxidatively drying paste inks (for example, sheetfed). amine number (value), n—the relative number of –NH 3 groups on a polymer or other molecule as determined by the milligrams of potassium hydroxide equivalent to the amine groups in one gram of the material. antioxidant, n—organic compound added to a resin, vehicle, or other material to retard oxidation, deterioration, and rancidity. apparent viscosity (VD), n—measured viscosity of a non- Newtonian fluid at a particular shear rate D. D ISCUSSION —A shear rate of 2500 s -1 has been found useful for printing inks. biocide, n—a substance that kills microorganisms such as bacteria, molds, slimes, fungi, etc. D ISCUSSION —Typically used in aqueous printing ink systems. cellulose acetate butyrate (CAB),cellulose ethers (ethyl cellulose), n—synthetic polymers formed by the reaction of wood pulp with sodium hydroxide and ethyl chloride. clarity, n—the characteristic of a transparent body whereby distinct high-contrast images or high-contrast objects (sepa- rated by some distance from the body) are observable through the body. cloud point, n—point at which compatibility is lost causing a resin/solvent mixture to become turbid and lose clarity. coagulum, n—clot, curd, or coagulated albuminoid substance. cohesion, n—force by which the molecules of a substance are held together. cold cut, n—dispersion of resin into solvent using high shear dispersion without external heating. colloid, n—solid, liquid, or gaseous substance made up of very small, insoluble, nondiffusible particles that remain in sus- pension in a surrounding solid, liquid, or gaseous medium of different matter. compatibility, n—ability ofa mixture oftwo or more materials to form a clear, homogeneous, and stable solution at room temperature. crosslinking, v—union ofhigh-polymer molecules by a system involving primary chemical bonds that is done either by addition of a chemical substance (cross-linking agent), exposing the mixture to heat or by subjecting the polymer to high-energy radiation (UV or EB). cure, v—the chemical conversion from a wet film to a solid dry film. dissolution, v—point at which all resin completely dissolves in the solvent. elastomer, n—any rubber-like substance or polymer. exempt volatile compound, n—organic compounds that do not participate significantly in atmospheric photochemical reactions. electron beam, n—conversion of an applied film from its application state to its final use state by means of a mechanism initiated by electron beam radiation generated by equipment designed for that purpose.energy curing, v—a graphic arts process for the conversion of an ink or coating to a solid film whereby reactive materials are polymerized when exposed to a high energy source such as ultraviolet or an electron beam. evaporation, v—change from the liquid state to a gaseous or vapor state as when solvent leaves a wet film. film former, n—a material that when applied to a substrate provides a continuous layer. fumaric resin, n—synthetic polymers formed by the addition reaction of fumaric acid to compounds containing conju- gated double bonds such as rosin, tall oil or rosin acid, followed by esterification with polyhydric acids. D ISCUSSION —Fumaric resins can be used in both liquid and paste printing inks.