Introduction and processing guidance of Oster eva foil1. The composition of EVA foil
EVA laminated glass film is modified by using EVA resin (ethylene acetate polyethylene copolymer) and adding various plastic additives to make it have excellent optical properties, anti-aging properties, and good adhesion to glass and other substrates.it is the adhesion interlayer of laminated safety glass and single layer laminated glass
2. Other names of EVA foil
EVA foil industry is also called EVA foil,Evguard, EVALAM, EVALAM VISUAL, EVASAFE, OSTER AS FILM
3.The function of eva foil
1. Safety: Because EVA resin has a filling function,
it has a adhesion function after heating. It is widely used in glass lamination with paper, cloth, silk, fabric, iron plate, wood board, plastic board, plywood board. especially the reprocessing of the glass with EVA film, not only enhances the thickness and strength of the glass (that is enhances the ability of the glass to withstand external impact), but also the glass slag is stuck by the film after the glass is broken. It won't fall and hurt people.
4.Application range of EVA glass film
In the glass deep processing industry:
1. Laminated glass film is widely used in the deep processing of laminated glass
2. Single layers laminated glass film is widely used in the deep processing of photo sliding door glass,kitchen,closet door
3. Smart glass
4. Solar Panel
5.Type of laminating furnace:
1. Double-function single-layer laminating furnace: the temperature is the easiest to control, the temperature uniformity is the best, and the yield is the highest
2. Double-station double-layer laminating furnace: the temperature is easy to control, the temperature uniformity is better, and the yield is relatively high
3. Multi-layer large box type laminating furnace: slow heating, poor temperature control, poor temperature uniformity, low yield
The multi-layer laminating furnace seems to be capable of mass production. In fact, the overall processing time is similar to that of single-layer and double-layer, and the temperature speed and temperature uniformity are not well controlled, and the yield is low. We generally recommend that customers use single-layer and double-layer Laminated furnace.
6.Temperature control of the laminating furnace: one is the surface temperature of the glass, that is, the sensor head that measures the temperature directly contacts the glass in the silicone bag. This temperature can best show the true temperature of the glass, the temperature is best controlled, and the heat preservation (constant temperature) time control Also the most accurate
The other is hot air temperature, that is, the sensor head that measures the temperature is outside the silicone bag without touching the glass. The constant temperature time must be long enough to ensure that the temperature in the silicone bag reaches the set value, the temperature is uniform, and a sufficient cross-linking reaction occurs. If the temperature is not enough or the constant temperature time is short, delamination is easy to occur
7.Several problems to be paid attention to in laminating furnace
(1)Temperature difference: The temperature difference refers to whether the temperature of the glass surface or the temperature of the hot air in the furnace is consistent with the temperature on the outside temperature indicator, how much difference is it, whether it is normal or negative. The temperature difference is generally normal within 5C, and abnormal if it exceeds 5C.
It is best to replace the temperature control system to ensure that the temperature is consistent inside and outside; if it is not replaced, it is recommended that the customer adjust the temperature relatively higher or lower to be consistent with our processing temperature
(2)Temperature uniformity: It is normal that the temperature difference of each point in the furnace is within 5C. If there is a large temperature difference at a point in the furnace, under the same constant temperature time, the film will react fully in the high temperature area, and the adhesion force will be strong, and the adhesion force in the low temperature area will be weak, easy to delamination, or show haze looks like not completely melted. It is recommended that the customer check if the local heating tube is damaged, or the heating tube spacing is too large, and if possible,installed fans in the furnace to accelerate the temperature evenly.
(3)vacuuming:the purpose of vacuuming is to exhause to avoid bubbles.The parts that are prone to problems with vacuuming are:
The exhaust hole in the silicone bag is blocked, and the air cannot be exhausted;
The silicone bag is damaged or the silicone bag is not properly sealed, or the mouth of the silicone bag is blocked by foreign objects, causing air leakage
The exhaust pipe is blocked and the air cannot be discharged
The vacuum pump is broken and the air cannot be pumped out
The vacuum pump must start from the pre-vacuuming and continue until the temperature of the glass drops below 50C after the silicone bag is out of the furnace, because the amount of glue is always flowing after the film is melted at 70 degrees. Once the intermediate stops, the air will not be exhausted and there will be bubbles. , If the vacuum is stopped prematurely after the oven is out, the air will enter the glass again with the flow of glue
The difference between EVA film and PVB film
1.The resins used are different:one is EVA resin,the other is PVB resin
2.The reprocessing equipment used is different: the glass deep processing equipment for EVA film is a laminating furnace, which is simple to operate and low investment.
The glass deep processing equipment for PVB film is an autoclave, which has high cost and complicated operation. After the film is combined, it must be pre-pressed, and then heated and pressurized in the autoclave. The price is more than one million yuan. The advantage is that it can be mass-produced. The defect is less order would result in high cost for processsing.
3.Water absorption rate is different: EVA film has a very low water absorption rate, less than 0.1%; PVB film has a high water absorption rate