Lactic acid ester reagent called the cleaner of lactate in English.Lactic acid is also called 2 - hydroxy propionic acid and propanol acid, its characteristic is containing hydroxyl group in the molecule, so has good hydrophilicity.Carboxylic acid esters generated more commonly is insoluble in water, but the lactic acid ester has certain solubility in water.Commonly used lactic acid ester cleaner is ethyl lactate, due to lactic acid ester can be formed by hydroxyl hydrogen bond between molecules, so is higher than the boiling point of general esters, commonly used lactic acid ester reagent boiling point range (145 ~ 190 degrees Celsius) in so although combustible, but has good security.Lactic acid ester cleaning agent can be mixed with many organic solvent free, it to oily dirt and water-soluble dirt has very good strength, but also for metals by cleaning the surface has good wetting ability, can make the surface after cleaning has the very good hydrophilicity.Lactic acid ester detergent with a small loss of use, good economy, had no adverse effect on material to be cleaned, non-toxic, the advantages of easy biodegradation, is a kind of new type of ODS solvent cleaner alternative cleaning agent.It is widely used in the electronics industry, such as used for all kinds of CD, LCD monitor, magnetic head, chips, circuit boards, modules, cleaning;Can also be used for optical lenses, printing plates, printing ink, metal cleaning.The cleaning method has a dip, spray washing, hand washing, combination of ultrasonic cleaning, etc.Lactic acid ester reagent defect is dry is poorer, therefore should be adopted in the drying process in isopropyl alcohol such as methanol or replacement.In Japan at present already with lactic acid ester detergent used by the distillation recycling system and combination cleaning device for cleaning system of complete sets of equipment.
Photoresist is composed of the three main ingredients : the photosensitive resin, photosensitizer and solvent .Photosensitive resin after illumination, the exposure area can quickly produce light curing reaction, making the physical properties of the material, especially for obvious changes such as solubility, affinity.Obtained with the appropriate solvent, solvent to soluble part, get the required image.Photoresist is widely used for printed circuit and integrated circuit manufacturing and printing plate-making process.Photoresist technology is complex, more varieties.According to the principle of its chemical reaction mechanism and the development, can be divided into two categories, negative photoresist and positive photoresist.Light form the unsolvable matter is negative photoresist;On the other hand, for some solvent is not to be dissolved, light into soluble substances is the positive photoresist.Based on the chemical structure of photosensitive resin, photoresist can be divided into three types.Type (1) light polymerization, the alkene monomers, under the effect of light generates free radicals, free radical monomer polymerization by any further, the generated polymers, has the characteristics of the form as.(2) light decomposition model, using materials containing azide quinone compounds, light, can produce light decomposition reaction, from oil soluble into water soluble, can be made into positive photoresist.(3) light crosslinking type, using polyvinyl alcohol lauric acid ester as photosensitive material, such as under the action of light, a double bond in the molecule is opened, and between the chain and chain crosslinking, forming a mesh structure of insoluble, and corrosion resistant effect, it is a kind of typical negative photoresist. Ethyl Lactate is a good solvent during the production of photoresist. Because Ethyl Lactate is biodegrdable, environmentally, especially, it can replace traditionaly solvent , like PMA,PM, NMP. In the process of remove residual gum, Ethyl Lactate can make strong solvency ,easily dissolve the residual photoresist.