JP2003086925A - Printed board with moisture-proofing structure and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printed board with moisture-proofing structure that can inexpensively realize a highly reliable waterproofing structure in a short lead time, and to provide a method of manufacturing the printed board. SOLUTION: A parts-mounted printed board 111 is hermetically sealed by coating the board 111 with a resin film 120. Consequently, the printed board with moisture-proofing structure can be provided at a low cost as compared with the conventional example, because no expensive filler nor connector is required. In addition, since the stress reduction required at the time of curing filler is not required, this printed board with moisture-proofing structure can be manufactured in a short lead time as compared with the conventional example. Moreover, since the board 111 is hermetically sealed with the resin film 120, no stress is caused by filler in parts junctions and the reliability of the board 111 can be improved as compared with the conventional example.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board with a moisture-proof structure and a printed circuit board with a moisture-proof structure, which is used in an electronic device which is likely to malfunction due to being used in a high humidity environment such as underwater and its vicinity. The present invention relates to a method for manufacturing a printed circuit board.

[0002]

2. Description of the Related Art Conventionally, many electronic devices have been used in severe environments, but high reliability and safety are required in any environment. In general, a printed circuit board on which a wiring pattern is formed and electronic components are mounted is used for an electronic device, and in order to ensure the reliability and safety of the electronic device, the printed circuit board is set at a temperature and a humidity. It is necessary to protect from various external factors such as. As a general method used to protect printed circuit boards with electronic components mounted from moisture, the sealed part of the housing that houses the printed circuit boards is liquid-tight with packing made of rubber or silicone grease. To secure, or to cover the entire printed circuit board, or part of it with resin,
There is a method of ensuring moisture resistance. Here, the latter method of ensuring moisture resistance by the resin layer formed on the surface of the substrate will be described below with reference to FIGS. 11 to 13.
A casting method or a dip coating method is generally used for forming the resin layer, but here, the resin layer is formed by the casting method. Here, FIG. 11 is a conceptual diagram of the component-mounted printed circuit board 2 after being installed in a casting mold, and FIG. 12 is a component-mounted printed circuit board 2 after casting.
13 is a conceptual diagram of the waterproof printed circuit board 10 after release.

First, since the printed circuit board absorbs moisture,
After being sufficiently dried by heating in an oven or the like, the electronic component 3 is mounted and the component-mounted printed circuit board 2 is produced. Next, as shown in FIG. 11, the component-mounted printed circuit board 2 is placed in a casting mold 6. The casting mold 6 is made of rubber or the like, and a protrusion 7 is provided therein, and the protrusion 7 determines the arrangement height and position of the component-mounted printed circuit board 2 in the mold 6. It Also, in the post process,
A mold release agent such as silicon is applied to the surface of the casting mold 6 so that the casting mold 6 can be easily released.

Next, as shown in FIG. 12, a filler 8 is injected into the casting mold 6. It is preferable that the filler 8 has excellent moisture resistance and insulation properties, and has a small stress applied to the electronic component 3, the solder, and the printed circuit board during curing or thermal change, and polybutadiene polyurethane or the like is used.
It is preferable that the filler 8 be filled so as to completely cover the component-mounted printed circuit board 2, but it is more preferable than a normal connector that is a connection terminal for supplying signals and power to the component-mounted printed circuit board 2 and the outside thereof. In the tall connector 9, the connection terminal portion 9 a of the connector 9 is exposed from the surface of the filler 8. After the filling, the filler 8 is hardened. Filler 8
There is a method of using ultraviolet rays or the like for curing the above, but heating is generally used. The curing conditions of the filler 8 are generally set at about 80 ° C. for 1 to several hours in consideration of the heat resistant temperature of the electronic component 3 mounted on the component mounted printed circuit board 2.

Next, as shown in FIG. 13, the component-mounted printed circuit board 2 sealed with the filler 8 is removed from the casting mold 6 to complete the waterproof printed circuit board 10.
However, there is a case where the casting mold 6 is formed of resin and is not released after the filler 8 is cured, and is used as a part of the waterproof structure. In this case, the releasing step is unnecessary.

[0006]

However, when the conventional waterproof structure for a printed circuit board described above is used, the filler 8 is used.
Is in close contact with the solder joint portion or the package of the electronic component 3, so that a solder crack is likely to occur at the joint portion of the electronic component 3 due to thermal change of the filler 8 due to curing or contraction of the filler 8. There is. Further, the filler 8 and the printed circuit board expand and contract due to the change in the operating environment temperature of the waterproof printed circuit board 10, but the stress caused by the difference in the amount of expansion and contraction of the both causes solder cracks in the joint portion of the electronic component 3. There is also a problem that it easily occurs. Further, when a heat-generating component is mounted on the printed circuit board, the heat dissipation is reduced by covering it with the filler 8, which causes problems such as circuit malfunction and component reliability. Further, in the case of adopting the method of releasing the casting mold 6, when the filler 8 is injected into the mold 6, the contact portion between the above-mentioned protrusion 7 holding the component-mounted printed circuit board 2 and the board 2. Since the filler 8 is not filled in the 7a, water may enter from the contact portion 7a after releasing the mold, which causes a problem that the water resistance is deteriorated. Further, in order to reduce the stress due to the shrinkage of the filler 8 that occurs when the filler 8 is cured, it takes several hours to cure the filler 8, and there is a problem that the lead time is long. Further, the connector 9 is a special product having a height for exposing it from the filler 8, and there is a problem that the cost is high. In addition, the filler 8 is generally expensive, a material cost of several hundred yen is required for one printed circuit board 2 on which components are mounted, and there is a problem that the cost is increased. Further, once the filler 8 is hardened, it is difficult to remove the filler 8 and it is difficult to recycle and repair the printed circuit board 2 on which components are mounted. The present invention has been made to solve such a problem, and has a moisture-proof structure that realizes a highly reliable waterproof structure for a printed circuit board on which electronic components are mounted, with a short lead time and low cost. An object of the present invention is to provide a printed circuit board and a method for manufacturing the printed circuit board with the moisture-proof structure.

[0007]

In order to achieve the above object, the present invention is configured as follows. That is, according to the moisture-proof printed circuit board according to the first aspect of the present invention, a component-mounted printed circuit board on which a component is mounted and a resin film surrounding the component-mounted printed circuit board, which surrounds the circuit board, is provided. A resin film that seals the component-mounted printed circuit board by bonding the resin film, and when the resin film is bonded, the resin film and the component mounted on the component-mounted printed circuit board And a contact prevention unit for preventing contact.

Further, the close contact preventing portion may be formed by a protruding member which is provided on the printed circuit board on which the components are mounted so as to protrude so as to prevent the close contact.

Further, when the resin film is formed of a plurality of layers, it may have a gas enclosing portion formed between layers in the plurality of layers and enclosing a gas.

When the resin film is adhered,
An inert gas or an antioxidant may be filled between the resin film and the component-mounted printed circuit board.

A printed circuit board with a moisture-proof structure according to a second aspect of the present invention is a printed circuit board on which components are mounted, and a resin film provided on the printed circuit board on which the component is mounted. Among the parts, for the exposing part, there is an opening for exposing the surface of the exposing part to the outside of the resin film, and the periphery of the opening is adhered to the exposing part, and the resin films are adhered to each other. And a resin film that seals the printed circuit board on which the components are mounted.

In the method for manufacturing a moisture-proof printed circuit board according to the third aspect of the present invention, a component-mounted printed board on which components are mounted is surrounded by a resin film, and the resin film and the component-mounted printed board are surrounded by the resin film. It is characterized in that the resin film surrounding the substrate is adhered to the printed circuit board on which the component is mounted, and the printed circuit board on which the component is mounted is hermetically sealed to produce a printed circuit board having a moisture-proof structure.

In the manufacturing method according to the third aspect, when a plurality of components are mounted on the component-mounted printed circuit board, and some of them are heat-generating components, after the surrounding,
It is also possible to expose the heat-generating component to the outside from the resin film before the bonding, to bond the periphery of the heat-generating component and the resin film after the exposure, and to further bond the resin film.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A printed circuit board with a moisture-proof structure and a method for manufacturing the printed circuit board with a moisture-proof structure, which are embodiments of the present invention, will be described below with reference to the drawings. still,
In each drawing, the same reference numerals are given to the same components. First Embodiment; FIGS. 1 and 2 show a printed circuit board 101 with a moisture-proof structure according to a first embodiment of the present invention. Here, the reference numeral 111 indicates the solder surface 111a.
The surface mount component 112 is a component mounted printed board on which the insert component 113 and the surface mount component 112 are mounted on the component surface 111b. The surface mount component 112 and the insert component 113 are collectively referred to as “component”. Such a printed circuit board 111 on which components are mounted is surrounded by a resin film 120, and the peripheral portion 12 of the resin film 120 is surrounded.
The printed circuit board 11 on which the above components are mounted by bonding 1
1 is sealed and the printed circuit board 101 with the moisture-proof structure is manufactured. This will be described in more detail below.

When the peripheral portion 121 of the resin film 120 is adhered to the component-mounted printed circuit board 111, the resin film 120 and the surface-mounted component 11 mounted on the component-mounted printed circuit board 111.
A protruding member 114 is provided so as to prevent the two and the insertion part 113 from coming into close contact with each other. The protruding member 114 is
This corresponds to an example that fulfills the function of an adhesion preventing portion that prevents the resin film 120 and the surface mount component 112 and the insertion component 113 from adhering to each other. Protrusion member 114
As shown in the figure, for example, the projecting places are preferably at four corners of the component-mounted printed board 111, and in addition to the four corners, they may be installed at the central portion of the component-mounted printed board 111. Further, in the present embodiment, since the components are mounted on both sides of the component-mounted printed board 111, the protrusion members 114 are provided on both sides of the component-mounted printed board 111 so as to project. However, in the case of single-sided mounting, for example, it may be provided on only one side.
However, when the lead of the insertion part 113 exists, it is necessary to project it on both sides. In addition, the protruding member 114 and the resin film 120 are the same as the tip portion 114 a of the protruding member 114.
Therefore, the protrusion 114 should prevent the resin film 120 from being damaged. Therefore, the tip portion 114a of the projecting member 114 can be formed in a shape that does not damage the resin film 120, and can be formed in a hemispherical shape as shown in FIG. 8, and the material of the projecting member 114 is ABS resin. Further, the height H of the protrusion member 114 is determined in relation to the heights of the surface mount component 112 and the insertion component 113 based on the function of the protrusion member 114 for preventing the close contact, and is 10 mm in the present embodiment.

The material of the resin film 120 is preferably a resin material having a low moisture absorption amount among the commonly used resin materials in order to exert the moisture absorption effect in the printed circuit board 101 having a moisture-proof structure. In this embodiment, the moisture absorption amount is preferable. Uses high density polyethylene with very few In consideration of the strength of the resin film 120, its thickness is 0.2 mm.
In the present embodiment, as shown in FIG. 2, two resin films 120 are used so as to sandwich the component-mounted printed circuit board 111 from both sides thereof, but the present invention is not limited to this, and one resin film 120 is provided so as to wrap both sides. The resin film 120 may be bent and used, or a resin film formed in an envelope shape in advance may be used to insert the component-mounted printed circuit board 111 into the envelope resin film. In the present embodiment, the two resin films 120 are dimensioned so that a margin of about 10 mm is provided around the component-mounted printed circuit board 111 in consideration of the subsequent steps. Further, four vinyl chloride coated wirings 115 extend from the component-mounted printed board 111 for inputting / outputting signals to / from the component-mounted printed board 111 and supplying power.
These wirings 115 are also sandwiched and sealed by the resin film 120 as shown in FIG.

A method of manufacturing the printed circuit board 101 with the moisture-proof structure thus configured will be described below. First, the printed circuit board before component mounting is sufficiently dried by a heating and drying device such as an oven, and then the above components are mounted using general equipment and construction methods. Further, in the mounting process, the protruding member 114 is mounted on the printed board. In the mounting step, the component mounted printed circuit board 111 is manufactured.
Further, after the drying, it is desirable to work in an atmosphere having a humidity of 30% or less in the steps until the printed circuit board 111 on which the components are mounted is sealed with the resin film 120. Next, as shown in FIG. 2, the component-mounted printed circuit board 111 is arranged between the two resin films 120.

Next, the peripheral portions 121 of the two resin films 120 facing each other are adhered to each other with a width of about 10 mm by thermocompression bonding by a hot press in this embodiment, and the two resin films 120 are used for component mounting. Printed circuit board 11
Seal 1 The thermocompression bonding conditions are set at 0.degree. C. for 1 second at 140.degree. C. in consideration of the melting points of polyethylene that is the material of the resin film 120 and vinyl chloride that is the material of the wiring 115.
The pressure was applied with a force of 4 MPa. As a result, as shown in FIG. 1, a printed circuit board 101 with a moisture-proof structure is manufactured in which four vinyl chloride coated wirings 115 are drawn from the printed circuit board 111 on which components are mounted.

When sealing the component-mounted printed circuit board 111 with the resin film 120, as an additional step, an inert gas is introduced into the gap 116 formed between the resin film 120 and the component-mounted printed circuit board 111. Alternatively, the antioxidant 117 may be enclosed. In this way, by sealing the inert gas 117 or the like in the gap 116, it is possible to prevent the printed circuit board 111 on which the components are mounted and which is sealed with the resin film 120 and the above components from being oxidized.

In this embodiment, two resin films 12 are used.
After sandwiching the component-mounted printed circuit board 111 with 0, the peripheral portions 121 on the four sides of each resin film 120, which is, for example, a rectangle, were thermocompression-bonded, but the mounting method of the component-mounted printed circuit board 111 and the resin film 120 The bonding method is not limited to this.

As described above, according to the moisture-proof structured printed circuit board 101 of the present embodiment, the component-mounted printed circuit board 111 is covered with the resin film 120, and the component-mounted printed circuit board 111 is sealed. Therefore, unlike the conventional method, it is not a method of sealing the component-mounted board by injecting the filler 8, so that it is not necessary to use the expensive filler 8 and the printed circuit board with the moisture-proof structure can be manufactured at a lower cost than the conventional one. 10
1 can be realized. Further, since it is not necessary to use the expensive connector 9 which is used due to the sealing with the filler 8, it is possible to realize the printed circuit board 101 with the moisture-proof structure at low cost. Further, the printed circuit board 1 on which components are mounted by adhering the resin film 120
Since 11 can be hermetically sealed, there is no problem that the lead time becomes long due to stress reduction at the time of curing the filler unlike in the conventional case. Therefore, it is possible to realize the printed circuit board 101 with a moisture-proof structure with a shorter lead time than the conventional one.

Further, since the substrate on which the components are mounted is not sealed by injecting the filler 8 but is sealed by the resin film 120, heat change of the filler 8, shrinkage of the filler 8, and the filler 8 as in the conventional case. The occurrence of solder cracks at the component joint due to the stress caused by the difference in shrinkage between the substrate 2 and the substrate 2 is eliminated. Therefore, it is possible to provide the printed circuit board 101 with a moisture-proof structure that is more reliable than the conventional one. Further, by providing the resinous protruding member 114 on the component-mounted printed circuit board 111, the resin film 120 contacts the surface-mounted component 112 and the insert component 113, and the resin film 120 and the lead 113a of the insert component 113.
It is possible to prevent contact with the component, solve the problem of solder cracks that occur at the joints of components, and prevent the component and the lead 113a from tearing the resin film 120. Therefore, it is possible to provide a more reliable printed circuit board 101 with a moisture-proof structure.

Further, since the substrate on which the components are mounted is not sealed by injecting the filler 8 but is sealed by the resin film 120, the heat generated from the components is dissipated to the outside through the gap 116 and further the resin film 120. As a result, the heat dissipation is better than in the conventional case, and it is possible to reduce the occurrence of malfunction of the circuit due to heat and the decrease in reliability of parts. Furthermore, the component-mounted board is not sealed by injecting the filler 8 but is sealed by the resin film 120, and the resin film 120 is not bonded to the component-mounted printed board 111. Therefore, printed circuit board 1 with parts mounted
11 and the resin film 120 can be separated, and the printed circuit board can be easily recycled and repaired. In addition, since the resin film 120 is used for sealing instead of sealing the component-mounted board by injecting the filler 8, the conventional filler 8 is used.
The interface between the substrate and the substrate 2, that is, the contact portion 7a does not exist. Therefore, the phenomenon that water enters from the contact portion 7a and the water resistance of the component-mounted printed circuit board is lowered does not occur. As described above, according to the printed circuit board 101 with the moisture-proof structure of the present embodiment, it is possible to realize a highly reliable waterproof structure with a short lead time and a low cost as compared with the related art.

Second Embodiment: A printed circuit board 102 with a moisture-proof structure according to a second embodiment of the present invention is shown in FIGS.
Will be described below. As shown in FIG. 3, in the moisture-proof printed circuit board 102, the resin film 130 corresponding to the resin film 120 of the moisture-proof printed circuit board 101 described above is provided with a gas filled portion, which is the moisture-proof structure of the first embodiment. It is different from the structured printed circuit board 101. Other configurations are the same as those of the printed circuit board 101 with the moisture-proof structure, and the description thereof will be omitted. Each resin film 1
The numeral 30 is formed of a plurality of layers, and the gas enclosing portion 131 for enclosing gas is formed between the layers in the plurality of layers. More specifically, one resin film 130 used in the second embodiment has an upper film 132 and a lower film 133 as shown in FIG. 4, both of which have elasticity and Excellent gas flexibility 13
A material that is easy to form 1 is preferable. In the second embodiment, a styrene elastomer having a thickness of 0.1 mm is used.

With respect to the upper film 132 and the lower film 133, first, the upper film 132 and the lower film 133 are superposed on each other, and thermo-compression bonding is carried out at the adhering portions provided at the adhering interval W1 with the width W2. Therefore, the upper film 132 and the lower film 133 are adhered to each other in the adhesive gap W1. still,
In the second embodiment, the bonding distance W1 is 10 mm and the width W2 is 2 mm. Next, the upper film 13
A non-adhesive portion between the lower film 133 and the lower film 133, that is, a plurality of gas-filled portions 131, such as a hemispherical shape as shown in the figure, or a semi-cylindrical shape in which semicircles are continuous over a certain distance. The gas filled portion 131 of is formed. In this way, one resin film 130 is formed. It should be noted that the form of the gas sealing portion 131 is not limited to the above-described one, and, for example, as shown in FIG.
One gas sealing part 1 for one resin film 130
31 may be formed. That is, the number of the gas filled portions 131,
The shape and the like are appropriately determined depending on the environment in which the moisture-proof printed circuit board 102 is used.

A method of manufacturing the printed circuit board 102 with a moisture-proof structure using the resin film 130 will be described. The description of the same steps as those of the method of manufacturing the printed circuit board 101 with the moisture-proof structure described above will be omitted, and only different steps will be described. The component mounted printed circuit board 111 is installed between the two resin sheets 130 formed as described above, and the two resin sheets 130 having a rectangular shape, for example.
The three sides are bonded by thermocompression bonding. Next, a gap 116 between the two resin sheets 130 and the component-mounted printed circuit board 111.
While the nitrogen gas as the inert gas 117 is sealed in, the remaining one side is bonded by thermocompression bonding. As a result,
As shown in, it is possible to realize the printed circuit board 102 with a moisture-proof structure in which four vinyl chloride coated wirings 115 are drawn out.

The moisture-proof printed circuit board 102 manufactured in this manner can achieve the above-mentioned effects of the moisture-proof printed circuit board 101 of the first embodiment, and further has a gas sealing portion 131. By having the sheet 130, it is possible to absorb an impact from the outside to the component-mounted printed circuit board 111,
Further, it is possible to make the temperature change around the component-mounted printed circuit board 111 slow with respect to the rapid temperature change around the moisture-proof structure printed circuit board 102. Furthermore, the periphery of the printed circuit board 111 on which the components are mounted, that is, the gap 116
By encapsulating the inert gas 117, in this example, nitrogen gas, it is possible to prevent the component-mounted printed circuit board 111 from being oxidized. Thus, the printed circuit board 10 with the moisture-proof structure
According to 2, it is possible to provide a printed circuit board with a moisture-proof structure having higher reliability than the printed circuit board 101 with a moisture-proof structure of the first embodiment.

Third Embodiment: A printed circuit board 103 with a moisture-proof structure according to a third embodiment of the present invention will be described below with reference to FIGS. 6 and 7. Printed circuit board with moisture proof structure 10
3 has a component-mounted printed board 151 corresponding to the component-mounted printed board 111 described above. The component-mounted printed circuit board 151 is a substrate having heat-generating components 112-1, 113-1 as described below, but is substantially the same as the component-mounted printed circuit board 111. Therefore, detailed description of the component-mounted printed circuit board 151 is omitted.

As shown in FIG. 6, the surface of the moisture-proof printed circuit board 103 is exposed to the outside of the moisture-proof printed circuit board 103 among the above components when a plurality of the components are mounted on the printed circuit board. There is an exposed component that needs to be mounted, and the printed circuit board 1 on which the component is already mounted
The surface of one side of 51 has a card connector portion 150 for electrical connection with another substrate. Therefore, the exposing component and the card connector portion 15
0 is exposed to the outside of the resin film that seals the component-mounted printed circuit board 151, which is different from the above-described printed circuit boards 101 and 102 with the moisture-proof structure. The description of the same components as those of the moisture-proof printed circuit board 101 is omitted. As an example of the exposing component, in the third embodiment, the heat generating component 112 shown in FIG.
-1, 113-1 corresponds. These heating components 112
A heat radiating plate 118 made of, for example, aluminum is attached to the surfaces of -1, 113-1.

The material, the overall shape of the resin film 140,
The overall size and thickness are the same as those of the resin film 120 described above.
9 is similar to that of FIG.
As shown in FIG.
An opening 141 is provided at a position corresponding to the heat radiating plate 118 so as to penetrate through and be exposed. The size of the opening 141 is slightly smaller than the size of the heat dissipation plate 118 as shown in FIG.
The size is such that it is press-fitted in the first embodiment, and in the present embodiment,
The size is such that each side of the heat dissipation plate 118 is shifted inward by about 2 mm.

Further, in the printed circuit board 103 with the moisture-proof structure,
As shown in FIG. 7, a part of one side of each of the resin films 140, which is, for example, a rectangular shape, is part-mounted printed circuit board 151 so that the card connector portion 150 is exposed to the outside on the outside of the resin film 140. On both surfaces, that is, the solder surface 111a and the component surface 111b. In order to improve the adhesive force in the adhesion, in the third embodiment, a plurality of through holes 152 penetrating the component-mounted printed board 151 are provided, and the front side and the back side of the component-mounted printed board 151 are provided through the through holes 152. The structure is such that the resin films 140 can be directly bonded to each other. The remaining portion of the periphery of each resin film 140 is thermocompression bonded at the opposing peripheral edge portions 142 of each resin film 140. Further, as described above, in the printed circuit board 103 with the moisture-proof structure, the heat dissipation plate 118 has the resin film 14
0, and because the resin films 140 are bonded to each other through the through hole 152, the protruding member 114 is located away from the heat dissipation plate 118 and the through hole 152 portion, that is, the card connector portion 150. It is provided in.
Therefore, the projection member 114 may not necessarily be provided at the four corners of the component-mounted printed circuit board 151.

A method of manufacturing the printed circuit board 103 with the moisture-proof structure thus configured will be described. The description of the same steps as those of the method of manufacturing the printed circuit board 101 with the moisture-proof structure described above will be omitted. Printed circuit board 15 with parts mounted
The resin film 140 is arranged so that the heat dissipation plate 118 attached to the heat generating components 112-1 and 113-1 mounted on the No. 1 and the opening 141 of the resin film 140 correspond to each other. Printed circuit board 151 with components mounted from both sides with resin film 140
Cover. At this time, the heat dissipation plate 118 is projected from the opening 141. Next, the opposing peripheral edge portions 142 of each resin film 140 are bonded by thermocompression bonding. Next, the heat dissipation plate 118 protruding from the opening 141 and the resin film 140, that is, the periphery of the opening 141 are bonded. In addition, it is effective to preliminarily roughen the surface of the heat dissipation plate 118 so that the adhesive strength with the resin film 140 can be improved. Finally, the component mounted printed circuit board 15 around the card connector section 150
1 through the resin film 140, the through hole 152
Glue through. Through the above steps, as shown in FIG. 6, it is possible to fabricate the printed circuit board 103 with the moisture-proof structure in which the heat dissipation plate 118 and the card connector portion 150 are exposed to the outside.

In the printed circuit board 103 with the moisture-proof structure,
Since the heat-radiating plate 118 is provided on the heat-generating components 112-1 and 113-1 and the heat-radiating plate 118 is exposed to the outside of the resin film 140, the moisture-proof structure of the printed circuit board 151 on which components are mounted is realized. , Heating component 112-1,
The heat of 113-1 can be efficiently radiated. Furthermore,
The resin film 1 is also used for the card connector portion 150.
Since the structure of exposing 40 to the outside is adopted, connection with other external terminals becomes easy. The structure of the moisture-proof printed circuit board 103 and the method for realizing the structure are not limited to the connection with an external module, but can be applied to, for example, a liquid crystal display unit. As a result, in addition to the effects of the first and second embodiments, it becomes possible to apply the moisture-proof structure to more substrate structures.

In the above-mentioned first and second embodiments,
Although the protruding member 114 is provided on the component-mounted printed circuit board 111 to prevent the resin film 120 and the component from contacting each other, the protruding member 114 is not an essential component. That is, as in the case of the printed circuit board 104 with a moisture-proof structure shown in FIG. 10, for example, two resin films 1 which are previously formed in a concave shape so that the resin film and the above-mentioned components do not contact each other.
25, and the peripheral edge 12 of the resin film 125.
When the 6 are bonded, the component-mounted printed board 111 may be sandwiched between the opposing peripheral portions 126 to support the component-mounted printed board 111 in the two resin films 125. In this case, the two resin films 125 correspond to an example that functions as an adhesion preventing portion that prevents the resin film 120 and the surface mounting component 112 and the insertion component 113 from adhering to each other.

Further, when the printed circuit board 111 on which the components are mounted is sealed with the resin film 120, gas is filled in the gap 116 at a pressure exceeding the atmospheric pressure so that the gap 116 is expanded and the resin film 120 and the resin film 120 are sealed. Contact with parts may be prevented. In this case, the gas filled in the gap 116 and having a pressure higher than the atmospheric pressure functions as an adhesion preventing portion that prevents the resin film 120 and the surface mounting component 112 and the insertion component 113 from adhering to each other. It corresponds to an example of fulfillment. In short, with the resin film surrounding the component-mounted printed circuit board 111, the resin film is adhered to the component-mounted printed circuit board 111 while preventing contact between the resin film and the component.
Should be sealed.

Further, it is also possible to adopt a structure in which the structures in the above-mentioned respective embodiments are appropriately combined.

[0037]

As described above in detail, according to the printed circuit board with the moisture-proof structure of the first aspect and the method for manufacturing the printed circuit board with the moisture-proof structure of the third aspect of the present invention, the printed circuit board on which components are mounted is made of a resin film. The resin film and the printed circuit board on which the component has been mounted are sealed so that the resin film and the printed circuit board on which the component is mounted are prevented from adhering to each other. Therefore, there is no need to use the above-mentioned expensive filler or connector because it is not the conventional method of sealing the component-mounted board by injecting the filler, and it is possible to print with a moisture-proof structure at a lower cost than before. A substrate can be realized. Further, since the printed circuit board on which the components are mounted can be sealed by bonding the resin film, there is no problem that the lead time becomes long due to stress reduction at the time of curing the filler unlike in the conventional case. Therefore, it is possible to manufacture the printed circuit board with the moisture-proof structure with a shorter lead time than the conventional one. Further, by preventing the adhesion between the resin film and the printed circuit board on which the component has been mounted by the adhesion preventing portion such as a protruding member, cracks are generated in the solder without applying unnecessary force to the joint portion of the component. There is nothing to do. It is also possible to prevent the resin film from being torn by parts or the like. Therefore, as described above, it is possible to provide a more reliable printed circuit board with a moisture-proof structure in the printed circuit board with a moisture-proof structure that can be manufactured at low cost and with a short lead time. In addition, since the resin film is used for sealing instead of sealing the component-mounted board by injecting the above-mentioned filler, the conventional heat change of the filler, shrinkage of the filler, and shrinkage rate of the filler and the board The occurrence of solder cracks at the component joint due to the stress caused by the difference is eliminated. Therefore, it is possible to provide a more reliable printed circuit board with a moisture-proof structure as compared with the conventional one.

By sealing an inert gas or an antioxidant between the resin film and the component-mounted printed circuit board, it is possible to prevent the component-mounted printed circuit board from being oxidized. Therefore, as described above, it is possible to provide a more reliable printed circuit board with a moisture-proof structure in the printed circuit board with a moisture-proof structure that can be manufactured at low cost and with a short lead time.

Further, by providing a gas-filled portion in the resin film, it is possible to buffer shocks, temperature changes, etc., which act from the outside on the printed circuit board on which the components are mounted. Therefore, as described above, it is possible to provide a more reliable printed circuit board with a moisture-proof structure in the printed circuit board with a moisture-proof structure that can be manufactured at low cost and with a short lead time.

Furthermore, according to the printed circuit board with the moisture-proof structure of the second aspect of the present invention and the method of manufacturing the printed circuit board with the moisture-proof structure of the third aspect, an opening for exposing the exposing component to the outside of the resin film is provided. Since it is provided on the resin film and the printed circuit board on which the component is mounted is sealed in the exposed state with the resin film, when the exposing component is, for example, a component that generates heat, good heat dissipation can be performed. . Therefore, as described above, it is possible to provide a more reliable printed circuit board with a moisture-proof structure in the printed circuit board with a moisture-proof structure that can be manufactured at low cost and with a short lead time.

[Brief description of drawings]

FIG. 1 is a view showing a structure of a moisture-proof printed circuit board according to a first embodiment of the present invention.

FIG. 2 is a perspective view for explaining a method of manufacturing the printed circuit board with the moisture-proof structure shown in FIG.

FIG. 3 is a diagram showing a structure of a printed circuit board with a moisture-proof structure according to a second embodiment of the present invention.

4 is an enlarged view of the resin film shown in FIG.

5 is a diagram showing a modified example of the printed circuit board with a moisture-proof structure shown in FIG.

FIG. 6 is a view showing a structure of a printed circuit board with a moisture-proof structure according to a third embodiment of the present invention, which is a cross-sectional view taken along the line I-I shown in FIG. 7.

7 is a plan view of the printed circuit board with a moisture-proof structure shown in FIG.

FIG. 8 is an enlarged view of the protrusion member shown in FIG.

9 is a plan view of the resin film shown in FIGS. 6 and 7. FIG.

FIG. 10 is a diagram showing a modified example of the printed circuit board with the moisture-proof structure shown in FIG. 1.

FIG. 11 is a diagram for explaining a structure of a conventional printed circuit board with a moisture-proof structure and a manufacturing process thereof.

FIG. 12 is a diagram for explaining a structure of a conventional printed circuit board with a moisture-proof structure and a manufacturing process thereof.

FIG. 13 is a diagram for explaining a structure of a conventional printed circuit board with a moisture-proof structure and a manufacturing process thereof.

[Explanation of symbols]

101, 102, 103, 104 ... Printed circuit board with moisture-proof structure, 111 ... Printed circuit board with components mounted, 112 ... Surface mount component, 113 ... Inserted component, 112-1, 113-
DESCRIPTION OF SYMBOLS 1 ... Heating component, 114 ... Protrusion member 117 ... Inert gas, 120 ... Resin film, 121 ... Peripheral part, 125 ...
Resin film, 126 ... peripheral portion, 131 ... gas filled portion,
140 ... Resin film, 141 ... Opening, 142 ... Peripheral part, 151 ... Printed board with components mounted.

Claims (8)

[Claims] 1. A component-mounted printed circuit board (111, 151) having components (112, 113) mounted thereon, and a resin film surrounding the component-mounted printed circuit board, wherein the resin film surrounding the substrate is When the resin film (120, 125, 130, 140) that adheres to seal the component-mounted printed circuit board and the resin film are bonded, are mounted on the resin film and the component-mounted printed circuit board. Adhesion preventive parts (114, 125) for preventing adhesion with the above parts
A printed circuit board with a moisture-proof structure, which comprises: 2. The printed circuit board with a moisture-proof structure according to claim 1, wherein the adhesion preventing portion is a protruding member (114) which is provided on the printed circuit board on which the components are mounted so as to project and which prevents the adhesion. 3. The printed circuit board with a moisture-proof structure according to claim 1, wherein, when the resin film is formed of a plurality of layers, the resin film has a gas filled portion (131) formed between layers in the plurality of layers and filled with a gas. . 4. The inert gas or antioxidant (117) is sealed between the resin film and the component-mounted printed circuit board when the resin film is adhered. The printed circuit board with a moisture-proof structure according to any one of 3 above. 5. A component-mounted printed circuit board (111) having a plurality of components mounted thereon, and a resin film provided on the component-mounted printed circuit board, wherein an exposing component (112-
1, 113-1) has an opening (141) for exposing the surface of the exposing component to the outside of the resin film,
A moisture proof, comprising: a bonding between the periphery of the opening and the exposing component; and a resin film (140) that seals the component mounted printed circuit board by bonding the resin films together. Printed circuit board with structure. 6. Parts (112, 113, 112-1, 1)
13-1) mounted component mounted printed circuit board (11
1, 151) to the resin film (120, 125, 13
0, 140), and the resin film surrounding the substrate is adhered while preventing the resin film and the component mounted on the component-mounted printed circuit board from adhering to each other, and the component-mounted print is performed. The printed circuit board with a moisture-proof structure (1
01, 102, 103, 104) is manufactured. 7. The moisture-proof structure according to claim 6, wherein an inert gas or an antioxidant (117) is sealed between the resin film and the component-mounted printed circuit board after the enclosing and before the bonding. Printed circuit board manufacturing method. 8. A plurality of components are mounted on the printed circuit board on which the components have been mounted, and a part of them is a heat generating component (1).
12-1, 113-1), the heat generating component is exposed to the outside from the resin film after the surrounding and before the bonding, and after the exposure, the periphery of the heat generating component and the resin film are bonded. The method for manufacturing a printed circuit board with a moisture-proof structure according to claim 6, further comprising adhering the resin film.