The method of LED wick sheet encapsulation transparent adhesive tape
Technical field
The invention belongs to the technical field of LED lamp production technology, particularly a kind of method of LED wick sheet encapsulation transparent adhesive tape.
Background technology
The LED lamp comprises substrate and chip, and chip is installed on the substrate and is arranged as several rows and some row, also need cover transparent adhesive tape on the chip usually and play a protective role.In addition, because the light that LED wick sheet sends is diffusion, lack guidance quality; Most of light is not directive the place ahead naturally and understandably, and therefore, people hope that again transparent adhesive tape can play the light guide effect; Promptly play and have the effect that is similar to convex lens; Make more concentrated area directive the place ahead of light, improve light utilization, reach the purpose of energy-conserving and environment-protective.
The mode of existing LED wick sheet encapsulation transparent adhesive tape has two kinds usually, and first kind is that one of transparent adhesive tape injection is preset as in the transparent plastic mould of lens shape, and transparent adhesive tape is solidified; The transparent plastic mould is fixedly mounted on the substrate, the transparent adhesive tape curvature that this mode obtains is desirable, stable again, but transparent adhesive tape can't directly cement on the chip; Need set up fixed structure and mould in addition; Thereby complex structure, technological process is many, and cost is high; And can there be air gap between LED wick sheet and the transparent adhesive tape, the influence heat radiation; Second kind is to utilize point gum machine that transparent adhesive tape is directly put to drip on the chip; But the transparent adhesive tape that this mode obtains is difficult to reliablely and stablely obtain desirable lens shape; The curvature on transparent adhesive tape surface is difficult to control; The transparent adhesive tape curvature randomness that each drop obtains is very big, and its curvature is very undesirable, wayward, unstable, thereby light guide effect is undesirable.So-called curvature is unstable, is meant that the curvature between the transparent adhesive tape that homogeneous drop not obtains differs greatly, and is not meant that the curvature on same transparent adhesive tape surface changes in time.
Summary of the invention
The objective of the invention is to overcome above-mentioned shortcoming and provide the method for a kind of LED wick sheet encapsulation transparent adhesive tape, the product structure that it obtains is simple, and the dimensionally stable of transparent adhesive tape is reliable, and transparent adhesive tape can directly cement on the chip.
Its purpose can realize by following scheme: a kind of method of LED wick sheet encapsulation transparent adhesive tape; It is characterized in that adopting the technology of silk screen printing, packaged transparent adhesive tape is selected the UV embossed printing ink for use, may further comprise the steps: (1), according to the arrangement position of LED wick sheet at LED lamp substrate; Design the printing position; Each chip correspondence is designed with a printing position, and this printing position covers corresponding chip, and the central point at printing position is aimed at the central point of chip; The position of respectively printing that designs is arranged as several rows; (2), prepare screen printing forme and scraper plate according to the printing position that designs; Prepared screen printing forme has several blank territory elements; The size of each blank territory element, position and the printing position of being designed are corresponding one by one, and each blank territory element of screen printing forme also is arranged as several rows; The base of prepared scraper plate is formed with several arc notch, and the quantity of arc notch is identical with the line number of the blank territory element of screen printing forme, and the position of each arc notch and the screen printing forme wherein position of the blank territory element of delegation are corresponding; (3), screen printing forme is placed on the LED lamp to be packaged, make the blank territory element of screen printing forme aim at the printing position of respective chip; End at screen printing forme is poured the UV embossed printing ink into; Scraper plate is begun to scrape from the screen printing forme face from an end of pouring the UV embossed printing ink into; The direction that scraper plate scrapes is to make the central point of each breach of scraper plate keep aiming at the center line of the blank territory element of screen printing forme corresponding line always; Make the UV embossed printing ink print to each above chip thus, form the thin ink lay in thick middle both sides from each blank territory element; (4), let the LED lamp that is printed on ink lay accept ultraviolet irradiation, ink lay is solidificated on each chip.Above-mentioned " UV embossed printing ink " claimed again " ultraviolet curing embossed printing ink ", or claims " UV type oil ", or claims that " the transparent embossed printing ink of UV " is a kind of known commercially available prod.
In each blank territory element of prepared screen printing forme, the perforate percentage successively decreases to this edges of regions from these zone central authorities gradually.
The arrangements of chips of packaged LED lamp becomes the some row of several rows, and each blank territory element of prepared screen printing forme also correspondence is arranged as the some row of several rows, has non-blank zone between every adjacent two row, also has non-blank zone between every adjacent two row.
The present invention has the following advantages and effect:
1, the present invention can make embossed printing ink through protrusion certain thickness on each chip behind the silk-screen owing to adopt the UV embossed printing ink; And scraper plate has arc notch, therefore after scraper plate is scraped, at the position the closer to the arc notch central point; The embossed printing ink that scraper plate blows off is few more; Therefore the ink thickness that stamps of this position is big more, otherwise, more away from the position of arc notch central point; The embossed printing ink that blows off is many more, so the ink thickness that this position stamps is more little.Like this, form thick middle and the thin gradually ink lay in both sides, this ink lay just plays the convex lens effect behind overcuring, can make more concentrated area directive the place ahead of light, improves light utilization, energy-conserving and environment-protective.
2, in the blank territory element of each of the screen printing forme that the present invention adopted; The perforate percentage successively decreases to blank edges of regions from blank zone is central gradually; Like this; Not only help strengthening the effect of above-mentioned the 1st middle ink lay " the thick middle both sides are thin gradually ", can also further form the effect of " thick middle and thin gradually " all around, make the convex lens better effects if.
3, ink lay can directly print and cement on the chip, simplifies the production process of each LED lamp, and simple in structure, cost is low.
4, the ink lay convex lens shape that obtains is obvious, and its curvature is reliable and stable, big random fluctuation can not occur.
Description of drawings
Fig. 1 is that a kind of LED lamp substrate, chip, three plan position approach, design and printing position concern sketch map.
Fig. 2 is the scraper plate shape sketch map that printing LED lamp shown in Figure 1 is adopted.
Fig. 3 is the screen printing forme structural representation that printing LED lamp shown in Figure 1 is adopted.
Fig. 4 is the inner perforate percentage change rule sketch map of each blank territory element among Fig. 3.
Fig. 5 adopts the ink lay plan position approach sketch map that obtains above the LED wick sheet of embodiment one packaging technology.
Fig. 6 is an A-A section enlarged diagram among Fig. 5.
Fig. 7 is a B-B generalized section among Fig. 5.
Fig. 8 is the ink lay plan position approach sketch map that obtains above the LED wick sheet of packaging technology of embodiment two.
Fig. 9 is a C-C section enlarged diagram among Fig. 8.
Figure 10 is a D-D generalized section among Fig. 8.
Figure 11 is the product generalized section that the technology of embodiment three obtains.
Embodiment
Embodiment one
A kind of method of LED wick sheet encapsulation transparent adhesive tape, the technology of employing silk screen printing, printed transparent adhesive tape is selected the UV embossed printing ink for use; May further comprise the steps: (1), according to the arrangement position of LED wick sheet 5 at LED lamp substrate 1; Design printing position 11, as shown in Figure 1, each chip correspondence is designed with a printing position 11; This printing position 11 covers corresponding chip 5, and the central point at printing position is aimed at the central point of chip; The position 11 of respectively printing that designs is arranged as triplex row four row, has 12 printing positions, and is corresponding to 12 chips 5, as shown in Figure 1; (2), according to the printing position that designs 11 preparation screen printing forme 2 and scraper plates 3; Shown in Figure 3; Prepared screen printing forme 2 has 12 blank territory elements 21; The size of each blank territory element 21, position and the printing position of being designed 11 are corresponding one by one identical; Each blank territory element 21 of screen printing forme also is arranged as triplex row four row, has non-blank regionally 22 between every adjacent two row, also has non-blank regional 22 between every adjacent two row.In each blank territory element 21 of prepared screen printing forme, the perforate percentage of screen printing forme is central from the zone to successively decrease to edges of regions gradually, as shown in Figure 4; The perforate percentage of screen printing forme successively decreases to the d zone from a is regional, b is regional, c is regional successively; Certainly at a intra-zone, the perforate percentage of screen printing forme also is to successively decrease gradually from the inside to surface, and b is regional, c is regional also is like this to the d zone; Therefore in each blank territory element; The perforate percentage is to diminish gradually from the inside to surface, and promptly mesh (referring to through hole) closeness is stepless successively decreases gradually, and the site becomes number to reduce gradually that (stain of illustrating among Fig. 4 is represented blind hole; Promptly this hole is plugged, so stain increases from the inside to surface gradually).Shown in Figure 2; The base of prepared scraper plate 3 is formed with three arc notch 31; The quantity of arc notch is identical with the line number of the blank territory element of screen printing forme, and the position of each arc notch 31 and the screen printing forme wherein position of the blank territory element 21 of delegation are corresponding; (3), beginning silk-screen operation, screen printing forme 2 is placed on the LED lamp to be printed, make the blank territory element 21 of each screen printing forme aim at the printing position 11 of respective chip; End at screen printing forme is poured the UV embossed printing ink into; Scraper plate 3 is begun to scrape from the screen printing forme face from an end of pouring the UV embossed printing ink into; Move towards the screen printing forme other end, the direction that scraper plate moves be make the central point of each breach of scraper plate keep aiming at the center line of blank territory element of screen printing forme corresponding line always (the M point is the central point of first breach 31 among Fig. 2, and Fig. 3 cathetus m is the center line of the blank territory element of first row; Scraper plate scrapes in the process; The M point keep being aligned in straight line m directly over, the central point of all the other two breach 31 is therewith roughly the same), make thus on the UV embossed printing ink bites each chip from each blank territory element; On each chip, form ink lay 4, its plan position approach relation is as shown in Figure 5; Shown in Figure 6, these ink lay 4 thick middle left and right sides are thin; See that from other direction these ink laies also are that both sides are thin before and after the thick middle, and are as shown in Figure 7, therefore in fact ink lay 4 is attenuation gradually around the thick middle, forms convex lens; Then have the subregion not stamp the UV embossed printing ink between each adjacent chips, these do not have the regional location of stencil corresponding with non-blank regional 22 position; (4), let the LED lamp that is printed on ink lay accept ultraviolet irradiation, ink lay is solidificated on each chip.
Embodiment two
The main distinction of embodiment two technologies and embodiment one is following three aspects:
(a), the arrangements of chips of embodiment two printing becomes delegation's four row, the position 11 of respectively printing that therefore designs is arranged as delegation's four row, and is as shown in Figure 8; The blank regional unit cell arrangement of screen printing forme becomes delegation's four row, and the ink lay unit (convex lens) that obtains is arranged as delegation's four row;
(b), in embodiment two, the arc notch quantity of scraper plate has only one;
(c), in embodiment two, in the blank territory element of each of prepared screen printing forme, the perforate percentage of screen printing forme from central authorities to around remain unchanged; Therefore the ink lay unit (convex lens) that obtains is convex at C-C on section, form the thin ink lay in the thick middle left and right sides, and is as shown in Figure 9; Then approximate rectangular on section at D-D; Shown in figure 10, the whole light guide effect that still has convex lens also can guide more concentrated area directive the place ahead of light.
All the other and embodiment one are basic identical.
Embodiment three
The main distinction of embodiment three technologies and embodiment two is:
(a), in embodiment three, the perforate percentage of screen printing forme successively decreases to edges of regions from zone central authorities gradually;
(b), in embodiment three; The position of respectively printing that designs is arranged as delegation's four row; But not obviously not at interval, there is not non-blank zone in the blank territory element adjacent columns of screen printing forme yet between each row, and the ink lay unit (convex lens) that obtains is arranged as delegation's four row; But be not interrupted between the adjacent columns, shown in figure 11.
In the present specification, so-called " OK " is comparatively speaking with " row ", and both can exchange, and only observer's angle change 90 spent.For example, if the chip of LED lamp has 5 row 30 row, we also can understand conversely to become and have 30 row, 5 row.In addition, " several rows " can be meant delegation, two row or multirows, and " some row " can be meant row, two row or multiple rows." the some row of several rows " can be meant delegation's one row under special circumstances.
In the silk-screen field, some regional mesh of screen printing forme is a through hole, and other regional mesh are blocked; During printing, printing ink drains to stock by through hole, and the zone that mesh stops up does not then stay printing ink, thereby the printing ink marks that acquisition has shape forms picture and text.In the present specification, " the blank zone " of so-called screen printing forme is meant that mesh is the zone of through hole; " the non-blank zone " of so-called screen printing forme is meant the zone that mesh is blocked." the blank territory element " of so-called screen printing forme is meant each chip to the blank zone of small pieces should be arranged, and the blank zone of these small pieces just is called one " blank territory element ".If two chips suffer very closely, " the blank territory element " that then two chips are corresponding can suffer very closely even connect together.
In traditional silk-screen field, screen printing forme " perforate percentage " is used to control printing ink of the same race and has different shading effects at different parts, and the ink colors that print off in the zone that the perforate percentage is big more is dense more.So-called perforate percentage is meant the ratio of certain regional open interior area of screen printing forme and this regional gross area.Certain regional opening percentage is big more, and then perforate closeness is more big, and the site becomes number big more; The perforate percentage is more little, and then perforate closeness is more little, and the site becomes number more little.