JPH02144540A - Method for cooling printing frame - Google Patents

Abstract

PURPOSE:To uniformly cool a mask film so that the mask film can be regulated to and maintained at an adequate temp. by passing flowing water which absorbs heat rays and allows the transmission of UV rays in the intermediate position between a light source and the printing frame. CONSTITUTION:A work 7 held in tight contact with the mask film 6 crimped between an upper frame 4 and a lower frame 5 of the printing frame is irradiated by the light source 2 of an exposing device. A water tank 9 for cooling which absorbs the heat rays and allows the transmission of the UV rays is provided in the intermediate position between the light source 2 and the printing frame 4 and the flowing water is passed in this position. The heat rays contained in the irradiation light are, therefore, absorbed at the time when the irradiating light from the light source 2 arrives at the mask film 6. The temp. rise of the mask film 6 is prevented in this way and the adequate patterns are printed on the work 7.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for cooling a baking frame, and particularly to a method for cooling a baking frame of a workpiece such as a printed circuit board to which a mask film sandwiched between an upper frame and a lower frame is tightly attached. Regarding cooling method.

[Conventional technology]

In recent years, ICs have become more integrated and the number of pins has increased, and surface mount types with narrow bin spacing have become more common, resulting in higher mounting and wiring densities on printed wiring boards. As the number of layers increases, high-density and high-precision wiring patterns are required.

In conventional exposure equipment, the mask film adsorbed to the workpiece surface expands and contracts due to the heat rays irradiated from the light source, resulting in dimensional errors in the printed workpiece and emulsion applied to the surface of the mask film. In order to avoid this, it becomes impossible to obtain the desired proper wiring pattern due to swelling of the workpiece and thermal deformation of the workpiece.
A cooling device is used that blows cold air onto the mask film.

The above-mentioned cooling device includes, for example, a cooling room equipped with a cooler etc. on the back side adjacent to the exposure room, and an air outlet equipped with a fan that blows the coolant obtained from the cooler side facing the exposure room. The air outlet is positioned close to the mask film of the printing frame that is transferred to the exposure chamber. In the case of a so-called double-sided exposure device that irradiates parallel light from both sides of a printing frame, for example, air vents are arranged respectively on the upper and lower sides of the printing frame.

[Problem that the invention attempts to solve]

However, since the above-mentioned cooling device has only one air outlet per mask, and the direction of the air blowing is fixed, the effective irradiation range of the mask film that is irradiated with parallel light cannot be cooled uniformly. First, there was the problem of uneven cooling of the mask.

This invention was made in view of the above problems, and by uniformly cooling the mask film and maintaining it at an appropriate temperature, it suppresses the temperature rise of the mask film and eliminates the effect of heat on the workpiece. The present invention provides a method for cooling a printing frame that prints an appropriate pattern on an object to be exposed.

[Means to solve the problem]

The present invention has been made to solve the above problems,
In an exposure device that uses a light source of an exposure device to irradiate a workpiece with a mask film sandwiched between an upper frame and a lower frame of a printing frame in close contact with the workpiece, a heat ray is absorbed at an intermediate position between the light source and the printing frame. In this method, the irradiated light from the light source is cooled by passing running water in a cooling water tank that transmits ultraviolet rays, and the irradiated light from the light source is heated in addition to the running water at an intermediate position between the light source and the baking frame. This is a method of cooling by passing through an absorption filter, and the method is characterized in that the flowing water has a speed that makes it impossible to generate bubbles.

[Effect]

In the present invention, with the above configuration, at the time when the light irradiated from the light source of the exposure device reaches the mask film,
In addition to the heat rays contained in the irradiation light being absorbed by the running water of the cooling water tank, if a heat ray absorption filter is used, the heat rays are further absorbed in this filter, and the ultraviolet rays penetrate the transparent portion of the mask film. 9 to print the image of the mask film onto the workpiece.Furthermore, by accelerating the speed of the flowing water to a speed that does not generate bubbles, uneven printing due to generated bubbles is prevented. Therefore, the mask film does not expand or contract due to the irradiation light, and not only does dimensional error not occur in the workpiece, but also the emulsion of the mask film does not swell and undergo thermal deformation.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 6. FIG. 1 is a vertically sectioned front view showing a schematic configuration of a first embodiment of the present invention. In the figure, reference numeral 1 denotes a frame-shaped mirror of an exposure device, and the mirror is assembled symmetrically in the left-right and front-back directions, and has flat reflecting surfaces 1a, lb, l on the inside.
It is made by connecting three hollow truncated pyramidal mirrors shaped like c in three stages so that the cross-sectional area decreases in the height direction.
The overall shape is tapered at the top. Reference numeral 2 denotes a rod-shaped light source of the exposure device, which is placed on top of a mirror and housed in a rectangular reflection box 3.

4 is a lower frame, the lower frame 4 and the upper frame 5 form a baking frame, and between the lower frame 4 and the upper frame 5, a mask film 6 facing the lower frame 4 side is tightly attached. A workpiece 7 is being held. Further, 8 is a sealing gasket. Moreover, the mirrors 1a, tb, and 1cIJ< are assembled so that each part of the mask film 6 is uniformly irradiated with the irradiation light from the light source 2.

The configuration of the above baking frame is for baking from the bottom frame side,
When printing from the upper frame side, the lower frame in the above configuration description may be replaced with the upper frame, and the upper frame may be replaced with the lower frame.

In the first embodiment, a cooling water tank 9 is provided in the conventional configuration as described above, at an intermediate position between the light source body 2 and the lower frame 4, that is, between the reflection box 3 housing the light source 2 and the mirror 1a.

Figure 2 shows the cooling water I! 9, in which FIG. 2 (A) is a plan view, FIG. 2 ([1) is a front view taken along line B-B in FIG. 2 (A), and FIG. 2 (C) is a front view of the same figure It is an enlarged view of part C in (B). As shown in the figure, the cooling water tank 9 has two glass plates 10.1) that absorb heat rays and transmit ultraviolet rays arranged in parallel.

The outer periphery of the upper temporary glass 10 is surrounded by a cushion member 18 via a holding fitting 15, and by inserting an O-ring 20 into a groove 18a provided on the outer periphery of the cushion member 18, the outer periphery of the temporary glass 10 is Presser metal fitting 15
It is closely attached to. On the other hand, the O-ring 22 is inserted into the groove 21 provided in the cushion member 18 that contacts the outer peripheral edge of the inner surface of the plate glass 10, and the tightening bolt i7a is held down by the metal fitting 1.
5 and tightens to the cushion member 18, the outer peripheral edge of the inner surface of the glass plate 10 and the cushion member 18 are brought into close contact.

The outer periphery of the lower temporary glass 1) is surrounded by a cushion member 19 via a holding fitting 16, and the cushion member 190 has a water absorption hole 13 in advance on the left side in the drawing.
a, 13b, 13c are bored in the cushion member 19 so as to communicate with the distribution water channel 12, and the water channels 14a, 14b, 14c, 14d, 14e, 14f communicating with the distribution water channel 12 pass through the cushion member 18 and connect to the cooling water tank 9. There are drain holes 13a' and 13b on the right side of the drawing.
', 13e' are bored in the cushion member 19 so as to communicate with the distribution waterway 12', and a waterway 14 that communicates with these drainage holes.
3' to 14r' are formed on the cushion member 18. In addition, an O-ring 24 is inserted into the groove 23 provided in the cushion member 18, and the bolt 17b is held down by the metal fitting 16.
/.By tightening to the John member 18, the inner peripheral surface of the glass plate 1) and the cushion member 18
and seal it. Furthermore, the O-ring 26 is inserted into the groove 25 provided in the cushion member 18, and the bolt 17c is tightened.
17d to the cushion member 18 via the 97237 member 19, the cushion member 1
8. Between 19 and cushion member 19 and water supply hole 13b
, and the waterway 14e.

In the first embodiment with the above configuration, cooling water is injected into the cooling water tank 9 through the distribution channel 12 and the water intake holes 13a, 13b, and 13C. The cooling water tank 9 is formed watertight around the two glass plates 10.1) by a cushion member 18.19, so that the injected cooling water does not leak (drain holes 13a', 13b', 13c). ' and the distribution channel 12' to the outside of the cooling water tank 9. Therefore, the heat rays of the projected light from the light source 2 to the lower frame 4-. are absorbed by the running water in the cooling water tank 9, and the ultraviolet rays of the projected light are Temporary glass 1), cooling water passes through the temporary glass 10, and irradiates the screen film 6 through the lower frame 4. Since the projected light of the mask films J and 6 contains almost no heat rays, the temperature does not rise, and an appropriate pattern can be printed on the workpiece 7.

FIG. 3 is a vertically sectioned front view of a second embodiment of the present invention. The configuration in which the second embodiment differs from the first embodiment is that the cooling water tank 9
is fixed to the light source 2 side of the lower frame 4 of the baking frame by a support member 4a, and the configuration of the cooling water tank 9 is the same as that of the first embodiment.

Therefore, the effects of the second embodiment are also similar to those of the first embodiment.

FIG. 4 is a front view showing a schematic configuration of the path of the irradiated light from the light source of the third embodiment of the present invention, and this embodiment is similar to the first embodiment. The difference in structure from the second embodiment is that the light projected from the light source 2 of the frame-shaped mirror 1 of the exposure device to the lower frame 4 of the printing frame is reflected by a reflecting mirror 27.
．． 28, and FIG. 4 shows a case where the cooling water tank 9 is arranged on the light source side of the lower frame 4.

In this case, the cooling water tank 9 is connected to the light source 2 as in the first embodiment.
Of course, it may be provided between the reflection box 3 containing the mirror 1a and the mirror 1a.

Although this embodiment is a case in which the light source is horizontally spaced apart from the baking frame due to restrictions on the placement location, it produces the same functions and effects as the first embodiment.

FIG. 5 is a longitudinally sectioned front view of a cooling water tank used in a fourth embodiment of the present invention. This cooling water tank 9a is different from the cooling water tank 9 used in the first and second embodiments in that the temporary glass io, 1i, which is a component of the cooling water tank 9a, is different from the cooling water tank 9 used in the first and second embodiments.
When the hot wire filter 29 is provided in parallel with the hot wire filter 29, the peripheral end of the hot wire filter 29 is held by a cushion member 19 that holds the periphery of the temporary glass 10.

Note that the heat ray filter 29 may be held by the cushion member 18.

With the above configuration, this embodiment has the effect of absorbing heat rays from the light irradiated from the light source 2 in the frame mirror I to the lower frame 4 more efficiently than the first and second embodiments.

FIG. 6 shows a cooling water tank 9 used in the fifth embodiment of the present invention.
It is a top view which shows the structure of b. The structural difference between the cooling water tank 9b of the fifth embodiment and the cooling water tank 9 of the first embodiment lies in the cooling water injection mechanism and discharge mechanism. That is, the injection and discharge mechanism of the cooling water tank 9b is such that a water absorption hole 30 and a drainage hole 31 are provided on one side of a cushion member 18 or 19 that seals and holds the four sides of two pieces of temporary glass spaced apart and arranged in parallel. The guide 32 provided in the water tank of the water suction hole 30 and the guide 33 provided in the water tank of the υ1 water hole 31 are individually mounted on opposing wall surfaces so that the cooling water can circulate in the water tank. Furthermore, a pump 34 is provided in the water injection conduit to the injection hole 30.

With the above configuration, in the fifth embodiment, the cooling water tank 9b' is provided between the light source (not shown) and the lower frame of the baking frame, as in the first embodiment, and the cooling water injected into the water tank 9b' is Since the water circulates in the water tank at a high speed and is discharged, it efficiently suppresses the temperature rise of the mask film installed between the lower frame and the workpiece, eliminates the influence of heat on the workpiece, and Burn the appropriate pattern. Moreover, by interposing the pump, the cooling water can be supplied to the water tank 9 at a high speed.
Since the cooling water is injected into the tank and discharged, the cooling water is not heated to the extent that bubbles are generated due to the heat taken from the irradiated light in the water tank. That is, in the fifth embodiment, uneven baking of the mask film due to air bubbles caused by the use of the cooling water tank 9b does not occur.

〔Effect of the invention〕

The present invention absorbs heat rays at an intermediate position between the light source and the baking frame,
A baking frame in which running water from a cooling water tank that transmits ultraviolet rays is used, and in addition to this running water, heat rays from a light source are removed by a heat ray filter, or the running water is accelerated to a speed that makes it impossible to generate bubbles. This is a cooling method. Therefore, the present application prevents the temperature of the mask film from rising even during printing work in a high-temperature atmosphere, prevents the emulsion from swelling and deforming due to heat, and prevents uneven printing due to the formation of air bubbles in the cooling water. It is possible to print an appropriate pattern onto the workpiece without any problems.

[Brief explanation of the drawing]

1 to 6 are drawings of embodiments of the present invention, in which FIG. 1 is a longitudinally sectioned front view showing the schematic configuration of the first embodiment, and FIGS. 2(A), (B), (C) ) is a configuration diagram of a cooling water tank used in the first embodiment, where figure (A) is a plan view and figure (B) is a front view cut along line B-B in figure (A). , Figure (C) is an enlarged view of part C in Figure (B), Figure 3 is a longitudinally sectioned front view of the second embodiment, and Figure 4 is an outline of the path of the irradiated light from the light source of the third embodiment. FIG. 5 is a vertically sectioned front view of the cooling water tank of the fourth embodiment, and FIG. 6 is a plan view showing the structure of the cooling water tank used in the fifth embodiment. l...Frame-shaped mirror of exposure device 2...Bar-shaped light source of exposure device...Reflection box 4...Lower frame...Upper frame
6... Mask films 9a, 9b... Cooling water tank 0.1)... Temporary glass 12... Distribution channel 3...
Water absorption hole 14... Water channel 5.1G... Holding plate I7... Tightening bolt 8.19... Cushion member 0.22, 24.26... O-ring 1.23.25... Groove 27.28...Reflector 9.
... Heat ray absorption filter 0 ... Water absorption hole 31 ... Drain hole 2.33.
...Nozzle 34...Pump Fig. 1 Fig. 3 Fig. 4 Fig. 5 Fig. 1] Fig. 6 +8 (+9)

Claims (3)

[Claims] (1) In an exposure device that uses a light source of an exposure device to irradiate a workpiece with a mask film sandwiched between an upper frame and a lower frame of a printing frame in close contact with the workpiece, a heat ray is emitted at an intermediate position between the light source and the printing frame. A method for cooling a baking frame, characterized in that heat rays from the light source are removed by passing running water in a cooling water tank that absorbs and transmits ultraviolet rays. (2) The method for cooling a baking frame according to item 1, characterized in that the irradiated light from the light source is cooled by passing through a heat absorption filter in addition to the running water at an intermediate position between the light source and the baking frame. . (3) The method for cooling a baking frame according to any one of items 1 and 2, wherein the flowing water has a speed that makes it impossible to generate bubbles.