From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
List of definitions for various types of untreated electrical insulating papers.
| Identifier | ExFiles\Box 24\2\ Scan238 | |
| Date | 30th January 1923 guessed | |
| ELECTRICAL INSULATING PAPERS (UNTREATED). 659 I. DEFINITIONS. In order to avoid the ambiguity associated with many of the terms in use in the paper trade, it is recommended that in defining papers for electrical purposes the following terms be adopted and that their use be confined to the materials described :— Paper. The term " Paper " denotes a matted or felted structure of fibrous material formed into a relatively thin sheet on a paper-making machine. Pure Manilla Fibre Paper. The term " Pure Manilla Fibre Paper " denotes paper made from Manilla Fibre only. Note.—The best paper would be made from new fibre. Manilla Paper. The term " Manilla Paper " denotes a strong paper made from Sulphite Wood Pulp, but may contain some manilla and hemp fibre. Note.—This paper is occasionally described as " Cartridge Paper." Rope Paper. The term " Rope Paper " denotes paper made from rope-ends. Note I.—Rope paper is liable to contain iron particles. Note II.—" Manilla " paper dyed red is sometimes designated " Red Rope Paper." Chemical Wood-Pulp. The term " Chemical Wood-Pulp " denotes wood-pulp prepared by a chemical process, as, for example, sulphate, sulphite and soda wood-pulp described below. Sulphate Wood-Pulp (Kraft) Paper. The terms " Sulphate Wood-Pulp Paper " and " Kraft Paper " denote paper made from wood-pulp only, by the sulphate process. Sulphite Wood-Pulp Paper. The term " Sulphite Wood-Pulp Paper " denotes paper made from wood-pulp only, by the sulphite process. Soda Wood-Pulp Paper. The term " Soda Wood-Pulp Paper " denotes paper made from wood-pulp only by the caustic soda process. Note.—Paper made by this process is a soft and bulky paper. Mechanical Wood-Pulp Paper (Core plate insulating paper). The term " Mechanical Wood-Pulp Paper " denotes paper made from wood by the mechanical pulping process. Jute Paper (Horn Fibre Paper). The term " Jute Paper " denotes paper made from jute fibre without the use of chemicals. Soda Rag-Pulp Paper. The term " Soda Rag-Pulp Paper " denotes paper made from rags only, by the caustic soda process. Lime Rag-Pulp Paper. The term " Lime Rag-Pulp Paper " denotes paper made from rags only, by the lime and carbonate of soda process. Rag Bond Paper. The term " Rag Bond Paper " denotes paper made from linen and cotton rags only, and weighing more than 13 lb. per ream (480 sheets), post size (21 in. x 16¼ in.). Rag Bank Paper. The term " Rag Bank Paper " denotes paper made from linen and cotton rags only, and weighing not more than 13 lb. per ream (480 sheets), post size (21 in. x 16¼ in.). Leather Paper (Fish Paper). The term " Leather Paper " denotes paper made from cotton rags only, and afterwards chemically treated (generally with zinc chloride) to produce a homogeneous sheet of celluvert. Tissue Paper. The term " Tissue Paper " denotes paper of which the weight of 2 000 square feet does not exceed about 9 lb. Best Rag Tissue (Condenser or Electrical Tissue) Paper. The terms " Best Rag Tissue Paper," " Condenser Tissue Paper " and " Electrical Tissue Paper " denote tissue paper made from rags only. Note.—The term " Electrical Tissue Paper " is generally used for the heavier grades. Cotton Tissue Paper. The term " Cotton Tissue Paper " denotes tissue paper made from cotton rags only. Silversmiths' Tissue Paper. The term " Silversmiths' Tissue Paper " denotes tissue paper made from rags only, grass bleached, and free from chemicals and loading material. Sulphite Tissue Paper. The term " Sulphite Tissue Paper " denotes tissue paper made from wood-pulp by the sulphite process, but may contain some rag pulp. | ||