What is IMD technology?
IMD, is the inner film printing injection molding technology, you can understand as a photo mirror print pattern and then flipped over, the color in the transparent sheet underneath, in this case to be able to let the pigment ink printed pattern more bright and sharp, but also to get a good color protection not to lose color, and then by sealing the white ink on the bottom,
in addition to supplementing the final to be a white color layer, but also on the printed Patterns in the injection molding process is not affected by the bottom of the material, and finally need to do a curing coating, the role of this is to avoid the injection molding process of high temperature and high-speed material in the mold cavity to the color pattern washed out.
Application of IMD technology
The most popular application of IMD technology is in traditional white goods, that is, our washing machines, microwave ovens, and rice cookers above the button, the advantage is to avoid long-term pressure on the function keys leading to color loss, but also with waterproof function.
The disadvantage is that the key feedback feels slightly poor, of course, you do not need to be as intensive as the keyboard as a high-frequency press, that feel is acceptable to the user within the range.
In the past
IMD technology was first applied to cell phone shell above is the use of pc material production, is the hard material IMD cell phone case, at that time, in addition to tpu mold technology is not mature, there is also IMD to do pc substrate out of the effect is very good,
hardness plus high-definition graphic with it is like a very high-level product, although the edge is also unable to do with the extension of the pattern, but still looks like a very textured and beautiful. It is a very textured and beautiful cell phone case.
With the development of technology, IMD technology in tpu was applied to popularize, but the early IMD tpu molds are front and rear split molds, the middle of the mold have a mold clamp line, we commonly known as the cloak position of the kind of scratching line.
Gradually some manufacturers do not come out of the clamp line, that is, the four sides of the line position of the IMD mold, the mold is actually a clamping line of the mold pushed to the edge of the combination of the IMD sheet material.
If the IMD sheet material and the mold deviation, the mold is a very high-level product. If the IMD sheet and mold deviation will also see the kind of scratching line, of course, not in the middle of so cut hand, especially in the iPhone6 after the edge of the product are a rounded edge is particularly concerned about this feeling.
Technology development segmentation
Later, the structure of tpu IMD quickly evolved on the basis of the plane into a small half-wrapped IMD, half-wrapped IMD, and full-wrapped IMD three kinds of structure.
Small half-wrap IMD
It refers to the size of the sheet and the sheet data to modify, to do with about 10% of the extended arc with the edge of the graphic, this structure is a very embarrassing design, early is a factory because of the equipment and development costs can not be done half pack imd, so it is designed to this false half pack, we can understand the structure of the small half pack, and later this structure was abandoned.
Refers to the pattern extends to the curved edge of 50% above, this phone case on Amazon and Alibaba is now very common, this looks like the extension of 50%, you will not think – in fact, the factory in order to pay for the cost of this effect, that is, each model molds have to open three sets of molds.
Three sets of molds are included “a sheet molding mold, a sheet molding after the cutting mold, a molding sheet After the cutting mold, a molding sheet injection mold phone shell mold,” the minimum requirements of the configuration should be two thermoforming machine + an injection molding machine, here I put this process flow to elaborate:
Graphic design → digital proofing → sheet printing → sheet bottom curing → sheet molding → sheet cutting → injection molding.
In fact, it is a fake full package, because the production is only 80-90% of the package, in fact, it is and half of the package of the enhanced version, the effect looks good, in fact, the phone case will become very thick, and easy to scrap, so many factories to abandon this program.
Each process is the cost of each item, if there is a problem in the middle, the final product will be scrapped. This kind of everyone looks and other a few dollars no difference between the phone case, in fact, has belonged to the phone case production technology in the more complex process, complexity is the main reason for too many processes.
The focus of IMD
The focus is graphic printing, mold precision graphic printing is divided into the following two kinds.
1. Traditional printing machine printing, do out of the graphic color stability, the disadvantage is that the order quantity is slightly large.
2. Digital printing, using modified Epson printing machine printing, the advantage is that the order quantity is lower than the traditional printing, the disadvantage is that the graphic color is not stable, and sometimes the nozzle state problem is not detected in time, playing out of the sheet is very poor, directly taken to the injection molding, then out of all the waste products.
Precision of mold
Even if the sheet is printed well, it is a waste of money to use an inferior mold for injection molding, our manufacturers generally use molds that do not have a line that will scratch the hand, and the other is that the mold and the sheet will not produce a deviation between the anastomosis or the holes are not aligned, some of the molds are in the camera holes above the mouth as the feed port, and finally in the feed port for the punching and cutting process,
if the operator is not careful with the process, it will be all the camera holes punched crooked, the previous process is wasted and produce inferior products. If the operator of the process is not careful, all the camera holes will be punched crooked, and all the previous processes will be wasted and inferior products will be produced.
In A word
The last thing I want to say is that in the early stages of mold development, if you use low-end steel as the mold material, the mold will start to produce all sorts of unforeseen minor problems after 30,000-40,000 injections, and usually the factory will not tell you or tell your peers that it was developed this way.
In fact, you only need to increase the cost of mold development costs of about 30% of the cost of the mold can be guaranteed in 100,000 times the injection will not occur big problems, but this also depends on the injection molding factory master for the mold daily production attention and maintenance.
Anyway, if the mold is done well there is no big problem, if the material is saved in various links, then the production will have all kinds of problems, affecting the whole product line and even the normal operation of the company.
Why emphasize the importance of the mold in IMD technology, because the precision of the mold to a certain extent determines the basis of the production of cell phone shells, cell phone shell molds are self-evident.