|
Basis weight and grammage are terms used in the pulp and paper industry and also for fabric industry to denote a measure of mass of the product per unit of area for a type of fabric, paper or paperboard. Two ways of expressing grammage are commonly used: * Expressed in grams per square meter (g/m2), paper density is also known as ''grammage''.〔International Standard ISO 536: Paper and board – Determination of grammage. International Organization for Standardization, Geneva.〕 This is the measure used in most parts of the world. * Expressed in terms of the mass (expressed as weight) per number of sheets, it is known as ''basis weight''. The convention used in the United States and a few other countries using US paper sizes is pounds of a ream of 500 (or in some cases 1000) sheets of a given (raw, still uncut) basis size. Japanese paper is expressed as the weight in kg of 1,000 sheets. ==Grammage== In the metric system, the mass per unit area of all types of paper and paperboard is expressed in terms of grams per square meter (g/m2). This quantity is commonly called ''grammage'' in both English and French (ISO 536), though printers in most English-speaking countries still refer to the "weight" of paper. Typical office paper has 80 g/m2, therefore a typical A4 sheet ( m2) weighs 5 g. The unofficial unit symbol "gsm" instead of the standard "g/m2" is also widely encountered in English speaking countries. Typically grammage is measured in paper mill on-line by Quality Control System (QCS) and verified by laboratory measurement. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Grammage」の詳細全文を読む スポンサード リンク
|