For copy paper, you can choose the following points.
Tensile strength: Tensile strength refers to the tension of paper or paperboard. Usually expressed in absolute tensile strength: that is, the tensile strength of the specimen with a certain width (Newton); or by splitting the length of the note: that is, a certain width of the paper in its own gravity to pull off when the necessary paper length (m), or with the transverse section of the tensile strength of the sample unit cross-section of the tensile strength (Newton/M 2) indicated. The higher the strength, the less easily the paper will be pulled bad. For example, use long paper to print statements, tables, put them on the wall, if the tensile strength of the paper, the report or table is not easy to break, the time will remain the same as the longer.
Elongation: The elongation is the paper or paperboard under a certain tension. The percentage of the length of the original specimen to the elongation at break. Elongation is an important index to measure the strength and toughness of paper. Elongation is associated with tensile strength. The higher the elongation, the more flexible the paper, paper is not easy to pull off, this point with the rubber band has similarities. If the elongation is too low, in the use of a careless will be able to break the paper, whether for office work or economically speaking, have adverse effects.
Tearing degree: Tearing is the force required to tear a predetermined specimen to a certain length, expressed as an ox (Dayton). The fracture of paper is the ability of paper and paperboard to contend with crack. Do not know if you have found that some of the paper once there is a rift is easily torn into two halves, which is too low tearing reason, so, when buying, you might as well take the sample tear to see, as far as possible to choose a high tearing paper.
Folding: Folding is refers to paper and paperboard under a certain tension, can withstand 180° reciprocating folding times. The previous number of folds is expressed. Folding is the ability to fold the paper. It is to a large extent related to elongation, users can be used when they will often fold paper to choose, but it is recommended to buy a high degree of folding paper.