การเลือกหลักการของกระดาษความร้อน

purpose
Thermal paper: used as a communication medium for text and graphics on a fax machine, i.e. as fax paper; Used as recording materials in medical and measurement systems, such as electrocardiogram drawings, thermal instrument recording paper, etc; Printing paper for internet terminals; In terms of commercial activities, it is used to create trademarks, sign codes (POS), and so on, with fax paper accounting for the largest proportion.
The production principle of thermosensitive paper is to apply micro particles of powder on a regular paper base, which are composed of colorless dyes such as phenols or other acidic substances, separated by a thin film. Under heating conditions, the film melts and the powder mixes to form a color reaction. The colored handwriting on thermosensitive paper is unstable and easily faded, making the content of the document difficult to recognize
The commonly used lottery tickets use thermosensitive paper.
Ordinary thermal paper is not suitable for long-term storage, but good thermal paper can be stored for 30 years or even longer.
principle
When the thermal paper is placed in an environment above 70 ℃, the thermal coating begins to change color. The reason for its color change also needs to be discussed from its composition.
There are mainly two types of thermal sensitive components in the coating of thermosensitive paper: one is colorless dye, also known as colorless dye; Another type is a color developer. This type of thermosensitive paper is also known as bipartite differentiation type thermosensitive recording paper.
The main substances commonly used as colorless dyes are: crystalline violet lactone (CVL) in the triphenylalkylphthalide system, fluorane system, colorless benzoyl methylene blue (BLMB) or spiropyran system, etc.
The commonly used dispersants are polyvinyl alcohol L-3266, polyvinyl alcohol GL-05, and polyvinyl alcohol KL-03 (produced by Japanese synthetic chemistry).
The commonly used additives for top and bottom coatings are: gohsefimer Z-200, polyvinyl alcohol T-350, and polyvinyl alcohol N-300.
The main substances commonly used as colorants are para hydroxybenzoic acid and its esters (PHBB, PHB), salicylic acid, 2,4-dihydroxybenzoic acid, or aromatic sulfones.
When thermosensitive paper encounters heat, colorless dyes and colorants react chemically to produce color. Therefore, when using thermosensitive paper to receive signals on a fax machine for printing or directly printing with a thermosensitive printer, the graphics and text are displayed. Due to the many varieties used as colorless dyes, the displayed handwriting colors vary, including blue, magenta, black, etc.
Purchasing
Thermal paper is specifically used for printing on thermal printers and thermal fax machines. Its quality directly affects the printing quality and storage time, and even affects the service life of printers and fax machines. The quality of thermal paper on the market is uneven, and the country has not yet introduced national standards. Many users are not clear about how to distinguish the quality of thermal paper, which provides convenience for many businesses to produce and sell low-quality thermal paper, causing losses to users. The light storage time is shortened, the handwriting is blurred, and the printer is severely damaged. This article tells you how to identify the advantages and disadvantages of thermal paper to avoid falling for it again. Thermal printing paper is generally divided into three layers, with the bottom layer being the paper base, the second layer being the thermal coating, and the third layer being the protective layer. The main factors affecting its quality are the thermal coating or protective layer,
If the coating of thermosensitive paper is uneven, it can lead to dark colors in some areas and light colors in others during printing, which can affect the printing quality