KR930005519B1 - Adhesive composition for use in the mounting of electronic parts - Google Patents

Abstract

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Description

Adhesive compositions for use in electronic component devices and methods for attaching electronic components to printed circuit boards using the same

1 is a schematic diagram showing the attachment of electronic components on a printed circuit board using the adhesive composition of the present invention.

Figure 2a is a plan view showing a printed circuit board in the applied adhesive composition.

FIG. 2B is a cross-sectional view of the printed circuit board of FIG. 2A. FIG.

2C is a cross-sectional view of a printed circuit board after disposing an electronic component.

FIG. 2D is a plan view showing the printed circuit board of FIG. 2C. FIG.

3 is a flowchart of another method for attaching an electronic component of the present invention.

4A to 4D are side views showing the attaching process based on the flowchart shown in FIG.

5 is a flowchart of another method for attaching an electronic component of the present invention.

6A to 6D are side views showing an attachment process based on the flowchart shown in FIG.

Figure 7a is a perspective view of the adhesive composition of the present invention supplied in a preferred form.

7B is a perspective view of the adhesive composition of the present invention applied by the use of a dispenser.

8A-8D are plan views showing patterns of painted adhesive compositions.

9 is a graph showing the relationship between the exposure time in UV light and the adhesive force for the adhesive composition of Example 1 and Comparative Example 1.

10 is a graph showing the relationship between the shelf life and the viscosity for the adhesive composition of Example 1 and Comparative Example 1.

Figure 11a is a plan view showing a printed circuit board after applying the adhesive composition.

FIG. 11B is a cross-sectional view of the printed circuit board of FIG. 11A after disposing the electronic component. FIG.

Figure 12a is a plan view showing a printed circuit board after applying the adhesive composition.

12B is a cross-sectional view of the printed circuit board of FIG. 12A after the electronic component is disposed.

13 is a cross-sectional view showing a painting head using an application process of the adhesive composition by a painting technique.

* Explanation of symbols for main parts of the drawings

1 printed circuit board 2 island

30,3 adhesive composition 4: ceramic capacitor

5: electrode of ceramic capacitor 6: minimold transistor

7: Lead of Mini Mold Transistor 8: Molten Solder

10: solder paste

The present invention relates to an adhesive composition for use in attaching electronic components on a printed circuit board, and also to a method for attaching an electronic component on a printed circuit board using the adhesive composition.

Recently, when electronic components such as resistor chips and condenser chips and the like are bonded onto a printed circuit board, such electronic components have been used for the use of photosetting adhesive compositions (for example, Japanese Patent Application Laid-open No. 58-180090). Is first fixed on the printed circuit board. In this way, the photosetting adhesive composition is applied to the intended position for the electronic component on the printed circuit board, and after the electronic component is pressed into the adhesive composition to which the electronic component is applied, the photosetting adhesive composition is further supplied with light supply. If it has a strong viscosity, the electronic components are fixed. When the photosetting adhesive composition is applied, the viscosity of the adhesive composition is inferior, so that the operation of the action is made easy to use a device for applying such an injector or the like.

When the electronic component is fixed, the fluidity of the adhesive composition is reduced and the adhesive force of the composition is increased by increasing the viscosity of the photosetting adhesive composition, so that the electronic component does not move out of position.

However, this method was disadvantageous because it was difficult to control the reaction at a time when the viscosity of the tacky composition by the supply of light increased. That is, if the reaction proceeds too far, the adhesion of the composition decreases or does not appear. On the other hand, if the reaction proceeds not far enough, the viscosity of the composition does not increase and the electronic components will move out of position easily.

In order to eliminate this disadvantage, the adhesive composition becomes possible not only as a thermosetting but also as a photosetting.

The degree of photosetting of this adhesive composition is due to the increase in the viscosity of the composition caused by the supply of sufficient light to fix the electronic component in the predetermined position and the curing reaction of the composition that no longer proceeds. Adhesive compositions handled with light to increase viscosity can be fully cured by heat supply.

This is made possible by preventing the adhesion of dust to the composition and increasing the thermal resistance of the composition. In some cases, if the degree of photosetting of the adhesive composition is controlled as described above, the curing reaction proceeds further when light is applied, so that the adhesion of the composition often decreases or does not appear.

If a conventional adhesive composition for use in the attachment of electronic components is used as shown in FIG. 14, and UV light is used to treat this adhesive composition 30 applied to the surface of the printed circuit board 1 The UV light reaches the inner portion of the adhesive composition 30 so that all the adhesive composition 30 is gelled.

After the adhesive composition 30 is hardened in the shape of a mound, each of the electronic components 4 and 6 is pressed toward the gelled adhesive composition, and the shape of the gelled adhesive composition does not change. Thus, the electronic components 4 and 6 are left on the printed circuit board 1 at a distance from the wiring pattern on the printed circuit board 1. In addition, the contact area between the adhesive composition 30 and the electronic components 4 and 6 is very small, so that the adhesive force of the composition is insufficient to fix the electronic components 4 and 6 on the printed circuit board 1. .

The inventors of the present invention have found that when an ultraviolet lamp is used, not only the ultraviolet rays are radiated but also generate heat, and this heat causes hardening of the adhesive composition.

This problem is caused by adhesive compositions that are sensitive to light and heat. This difficulty can be overcome by controlling the amount of light emitted from the lamp.

However, if the amount of light emitted from the lamp is always changing, it is impossible to accurately control the amount of light in the exposed adhesive composition.

The curing properties of the adhesive composition are easily affected by light or heat and the stability of the composition during storage becomes insufficient.

If the adhesive composition can be supplied to the printed circuit board in painting technology, the final attachment condition of the electronic component becomes extremely stable. However, the viscosity of the adhesive composition should be even lower than the adhesive compositions currently available.

To reduce the viscosity of the adhesive composition may contain a solvent, but it causes toxic problems. If the amount of filler in the adhesive composition is reduced, the relative amount of resin component used is increased resulting in an increase in price.

The adhesive composition of the present invention, which overcomes many of the disadvantages mentioned above and the drawbacks of the prior art, consists of photosetting and thermosetting resin fractions and long chain saturated fatty amides.

In a preferred embodiment, the resin component consists of a photosetting resin and a thermosetting resin.

In a preferred embodiment, the saturated fatty acid amide is prepared by the reaction of saturated fatty acid containing 9 to 12 carbon atoms having at least one tertiary amine.

In a preferred embodiment, it is saturated fatty acid steaamide.

The method for attaching an electronic component is a method for attaching an electronic component on a printed circuit board of the present invention which overcomes many of the disadvantages mentioned above and the drawbacks of the prior art. Supplying an adhesive composition, exposing the composition to light as a surface layer of the composition that is harder than the internal portion with sufficient adhesion to fix the electronic component, and exposing the composition to a surface layer of the composition for attachment. Pressing is done.

In a preferred embodiment, the adhesive composition is supplied by painting techniques by having a linear shape in a substantially rectangular shape in cross section.

In a preferred embodiment, the above-mentioned method also consists of coupling electronic components to a printed circuit board.

In a preferred embodiment, the heating of the composition is carried out using heat generated at the soldering time of the electronic component on the printed circuit board.

In addition, the present invention described here (1) the surface layer is more viscous even if the surface layer is hardened with light so as to be harder than the inner portion, the electronic component is printed circuit with high precision only to place the electronic component on the hardened surface layer The purpose of supplying an adhesive composition for use in the attachment of electronic components that can be fixed at a predetermined position on a substrate, and (2) reducing the curing rate to prevent excessive reduction of the adhesive strength of the surface layer at the time of light supply. The purpose of supplying an adhesive composition for use in the attachment of an electronic component containing a long chain saturated fatty acid amide, and (3) the attachment of an electronic component containing a long chain saturated fatty acid so that the viscosity can be reduced without adding a solvent. For the provision of an adhesive composition for use in an adhesive, and (4) an adhesive composition for use in the attachment of an electronic component having excellent stability during storage. Mokjeogwa for supplying water, allows an object to provide a method for mounting an electronic component at a predetermined position on the printed circuit board with high precision by use of the adhesive composition as mentioned above (5).

The adhesive composition of the present invention comprises several known materials. There are two necessary components in the adhesive composition: photosetting and thermosetting component, and long chain saturated fatty acid amide.

The resin component is sensitive to heat and light. The resin component contains at least one photosetting functional group and at least one thermosetting functional group. The photosetting functional group and the thermosetting functional group may be the same, but preferably these functional groups are different. Therefore, one resin (eg, photosetting resin) containing at least one photosetting functional group and one resin (eg, thermosetting resin) containing at least one thermosetting functional group are used together as a resin component. It is preferable.

Photosetting resins that can be used here are monofunctional resins and multifunctional resins that can be cured by UV light. Examples of monofunctional resins and multifunctional resins are monomers, oligomers and prepolymers of acrylates and methacrylates (hereinafter both are referred to as (meth) acrylates).

Examples of monofunctional (meth) acrylates are methoxyethyl (meth) acrylate, methoxypropyl (meth) acrylate, ethoxyethyl (meth) acrylate, ethoxypropyl (meth) acrylate, butoxyethyl (Meth) acrylate, butoxypropyl (meth) acrylate, phenoxyethyl (methyl) acrylate, phenoxypropyl (meth) acrylate, nonylphenoxyethyl (meth) acrylate, nonylphenoxypropyl (meth) Acrylate, benzoyloxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, And (meth) acrylates of compounds formed by adding ε-caprolactone to tetrahydroperfuryl alcohol.

Examples of multifunctional (meth) acrylates include polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylic Latex, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, allyl (meth) acrylic To the addition of ethylene oxide to tri (meth) acrylate and bisphenol A of compounds formed by adding propylene oxide to propane, di (meth) acrylate of esters formed from latex, hydroxypivalic acid and neopentyl glycol It is the di (meth) acrylate of the compound formed by. Also monomers, oligomers or prepolymers of alkyl (meth) acrylates can be used.

The monofunctional resin is preferably present in an amount of about 10 to 60 weight percent based on the total weight of the composition. The multifunctional resin is preferably present in an amount of about 0.01 to 10 weight percent based on the total weight of the composition.

Examples of thermosetting resins include one glycidyl group or an isocyanate group. Specific examples of thermosetting resins include epoxy resins (e.g., bisphenol A epoxy resins), polyimide resins, phenol resins, and melamine resins.

When an epoxy resin is used as the thermosetting resin, curing agents such as amines, acid anhydrides and polyols are used. When other curing resins other than the epoxy resin are used, the curing agent may be any conventional kind usually used for these thermosetting resins.

Examples of curing agents are amine-amides, melamines and derivatives thereof, ie diarylmelamines, aminonitriles ie diaminomaleonitrile, polyamine salts, tertiary amine salts, alicyclic amines, acid anhydrides, fluoroborateamine complexes , Imidazole and derivatives thereof, hydrazides of organic acids, polyphenols and polyols. Preference is given to aminonitriles, ie diaminomaleonitrile, amine-amides, fluoroborate-amine complexes, polyamine salts, melamine and derivatives thereof, ie diarymelamine, imidazole and derivatives thereof and organic acids.

The thermosetting resin is preferably present from about 30 to 80% by weight based on the total weight of the composition and the corresponding curing agent is preferably present from about 0.1 to 20% by weight based on the total weight of the composition.

In order to reduce the rate of cure, the adhesive composition of the present invention contains a long chain saturated fatty acid amide. Examples of long chain saturated fatty acid amides are those obtained by amidation of saturated fatty acids of the general formula C _n H _{2n + 1} COOH, where n is preferably about 9 to 21. Specific examples of saturated fatty acids are caproic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachnic acid and behenic acid. The amines used for the amidation of saturated fatty acids may be some of the known amines, with tertiary amines being preferred. Preferably, the long chain saturated fatty acid amide is swollen with an aliphatic alcohol, an aromatic solvent or a mixture thereof because of its high compatibility with the resin component. Specific examples of aliphatic alcohols that can be used to swell acid amides are methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and butyl alcohol.

Specific examples of aromatic solvents that can be used are benzene, toluene and xylene.

The long chain fatty acid amide is preferably present from about 1 to 20 weight percent based on the total weight of the composition.

In addition, optional components may be included in the composition, such as photosensitizers, photopolymerization initiators, polymerization inhibitors, organic peroxides, fillers, pigments, thixotropic agents, dispersants, antioxidants, surfactants, and other forms of additives.

Examples of photosensitizers are those in the form of molecular division and hydrogen extraction. Specific examples of the photosensitizers in the form of a molecularly divided form include benzoin alkyl ether, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, diethoxyacetophenone, and triclo It is loacetophenone. Specific examples of hydrogen-extracting photosensitizers include benzophenone + bis (diethylamino) benzophenone, 2,4-diethyl thioxanthone + p-dimethylaminobenzoate, benzyl, 2-alkylanthraquinone and 2-chloroanthra Quinones. Preferred is benzoin alkyl ether, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-L-phenyl propane-1-one, diethoxyacetophenone, benzophenone + bis (diethylamino) benzo Phenone, 2,4-diethyl thioxanthone + p-dimethylaminobenzoate, and benzyl.

Fillers that can be used in the composition include calcium carbonate, talc and the like. Surfactants can be some of the common types, including, for example, polyether type surfactants, which are preferred. Pigments may be part of a common class, with red pigments being preferred.

The adhesive composition of the present invention is prepared from a mixture of a photosetting resin and a thermosetting resin component with a long chain saturated fatty acid amide and any additives such as photosensitizers and photopolymerization initiators.

The adhesive composition for use in attaching the electronic parts obtained by this method contains a long chain saturated fatty acid such as steaamide or the like. Therefore, as shown in FIG. 1, when the adhesive composition 3 is exposed to ultraviolet rays, the ultraviolet rays do not reach the inner portion 3b of the adhesive composition 3, so only the surface layer 3a of the adhesive composition 3 is exposed. Only gels.

Although the surface layer 3a becomes harder than the inner portion 3b, it is more adhesive. For this reason, when each of the electronic components 4 and 6 is pressed toward the surface of the gelled adhesive composition 3, the adhesive composition in the shape of the mound enters the gap and the electronic components 4 and 6 are connected to the surface of the wiring pattern. It doesn't come up. Also, the contact area between the adhesive composition 3 and the electronic components 4 and 6 does not increase, and therefore the adhesive force of the composition 3 causes the electronic components 4 and 6 to be fixed on the printed circuit board 1. Is sufficiently increased.

The following describes a method for attaching electronic components on a printed circuit board.

First, as shown in FIG. 2A and FIG. 2B, it is observed in the space between the islands 2 of the wiring pattern formed in the surface of the printed circuit board 1 of the adhesive composition 3 of this invention.

Application of the adhesive composition 3 is carried out by painting techniques such as screen painting or the like.

UV light is then directed towards the surface of the printed circuit board 1 in the applied adhesive composition 3. Although the UV light causes the surface layer of the adhesive composition 3 to become harder than the inner portion, the surface layer becomes more adhesive. UV light can be emitted from chemical lamps, solar lamps, mercury lamps, and the like.

High pressure mercury lamps, metal halide lamps, or other lamps with strong illumination are used and exposure times are shortened.

Next, as shown in FIGS. 2C and 2D, electronic components such as the ceramic capacitor 4 and the mini-molded transistor 6 are disposed on the top of the adhesive composition 3, and sufficient pressure is applied to the adhesive. Feeding is effected through the composition 3. Here, the ceramic capacitor 4 and the mini mold transistor 6 are formed on the adhesive composition 3 when the electrode 5 of the ceramic capacitor and the lead 7 of the mini mold transistor 6 come into contact with the island 2. To place.

Other electronic components, such as resistor chips, can also be attached in this way.

While the viscosity of the adhesive composition 3 is increased by supplying UV light, retaining adhesive force allows the electronic components 4 and 6 to be attached onto the printed circuit board 1 without moving out of position.

In addition, since the curing of the adhesive composition is slow, it is very easy to adjust the range of the adhesive force and ensure accuracy. After the electrodes 5 of the ceramic 4 and the leads 7 of the minimold transistor 6 are bonded to the islands, heat is supplied to the adhesive composition to completely solidify.

3 and 4a to 4d show another method for attaching the electronic component of the present invention.

The following describes this invention in detail.

First, as shown in FIG. 4A, the adhesive composition 3 is applied to the space between the islands 2 of the printed circuit board 1.

The adhesive composition 3, which is more viscous with the supply of UV light, retains the adhesion in order to make the surface harder than the inner part.

Then, as shown in FIG. 4B, one of the electronic components 4 is disposed at the top of the adhesive composition 3. Next, as shown in FIG. 4C, the heat-adhesive composition is allowed to flow along the surface of the printed circuit board 1 with the electronic component in which the flow of the molten solder 8 is disposed and then completely solidified. The electrode 5 of the electronic component 4 is coupled to the island 2 of the printed circuit board 1 as shown in FIG. 4D.

5 and 6A to 6D show another method for attaching the electronic component of the present invention. The following describes the detailed method.

First, as shown in FIG. 6A, the solder paste 10 is supplied to the island 2 of the printed circuit board 1. Then, it is applied to the space between the islands 2 as shown in FIG. 6B of the adhesive composition 3. The applied adhesive composition 3 is exposed to UV light to increase the viscosity. The surface layer of the adhesive composition 3 is harder than the inner portion and retains adhesion. Next, as shown in FIG. 6C, one of the electronic parts 4 is pressed toward the surface of the adhesive composition 3 to attach. The printed circuit board 1 is then heated to dissolve the solder paste 10, while the electrodes 5 of the electronic component 4 are drawn on the islands of the printed circuit board 1 as shown in FIG. 6D. Is coupled to (2).

The heating at the stage of the solder reflow is for completely solidifying the adhesive composition 3.

The method for supplying the adhesive composition of the present invention by painting technique will be described later.

7A is the shape of the adhesive composition supplied by the painting technique. The width W ₂ and height H _{2 of the} supplied adhesive composition 3 can be precisely controlled by using this technique. If the height H ₂ of the adhesive composition 3 is not accurately controlled, the adhesion between the electrodes of the electronic component and the island of the wiring pattern will be unsatisfactory.

In the conventional feeding method using an injector, the adhesive composition 30 is supplied in the form of a round mound as shown in FIG. 7B. Therefore, it becomes difficult to induce the adhesive force between the adhesive composition 30 and the electronic component, otherwise the diameter of the base region of the adhesive composition 3 (slightly smaller than the distance W ₁ between the two islands 2) W ₃ )) becomes very large and height H ₃ becomes high.

When an injector is used for the application of the adhesive composition, as shown in FIG. 7B, only the highest point of the adhesive composition 30 contacts the electronic component.

On the other hand, since the adhesive composition 3 as shown in Fig. 7A is in contact with the electronic component along the top surface, the adhesive strength of the composition of the electronic component becomes strong.

The adhesive composition supplied to the printed circuit board may be in the form of drops, the shape of one line and several lines, or the shape of the line whose direction changes as shown in FIG. 8A. When the applied adhesive composition is in the shape of a line with changing direction, the shape as shown in FIGS. 8A and 8B is preferably for preventing air from being trapped in the area enclosed by the line.

The invention is further described with reference to the following examples.

Example 1

Adhesive composition (I) used for attachment of an electronic component is manufactured from the following component.

The delay of curing the adhesive composition (I) was obtained and its stability to storage was tested.

The results are indicated by the mark □ in FIGS. 9 and 10. In the delay test of curing, the test sample is placed 10 cm below the UV lamp (800 W / cm) and exposed to UV light from the lamp.

After exposure, the adhesion of the adhesive composition was measured.

In the stability experiments during storage, the test samples were placed in the atmosphere at 30 ° C. and after some time the viscosity of the adhesive composition was measured.

Viscosity was measured using an E-type viscometer at 3 ° cone, 0.5 ppm and 30 ° C. As shown in FIG. 9, the adhesive composition (I) of the present invention was slowly hardened, even when the exposure time of UV light was long in order not to reduce the adhesive force.

As shown in FIG. 10, the adhesive composition (I) of the present invention did not change its viscosity when stored for several days.

Comparative Example 1

The adhesive composition (II) used for the attachment of the electronic component was produced in the same manner as in Example 1, and no steaamide was added thereto.

The curing retardance and stability to storage of the adhesive composition (II) were tested.

The results are shown by the + sign in FIGS. 9 and 10. As shown in FIG. 9, the sensitivity of the adhesive composition (II) to UV light is so great that the exposure time is increased and the adhesive force is quickly dropped.

As shown in FIG. 10, the viscosity of the adhesive composition (II) begins to increase immediately upon storage at 30 ° C.

The viscosity of the adhesive composition was 180,000 CPS immediately after preparation at 30 ° C. The viscosity of the adhesive composition (I) containing steaamide was 150,000 CPS at 30 ° C. Thus, it was found that the viscosity at 30 ° C. decreased 30,000 CPS when steaamide was added to the adhesive composition.

Example 2

The adhesive composition (I) obtained in Example 1 was used to attach an electronic component on the following printed circuit board.

First, as in FIGS. 2A and 2B, the adhesive composition (I) (in this embodiment referred to the adhesive composition 3) is formed between the islands 2 of the wiring pattern formed on the surface of the printed circuit board. Scattered using an injector in the space.

In addition, the surface of the printed circuit board 1 to which the adhesive composition 3 was applied was exposed to UV light. The surface layer of the adhesive composition 3 was harder than the inside while being adhesive. Further, as shown in Figs. 2 and 2d, they are attached onto the adhesive composition 3 of the ceramic capacitor 4 and the mini-mold transistor 6, and fixed to the adhesive composition 3 by application of sufficient pressure from the print head. .

Electronic components were attached by an automatic positioning device. The adhesive composition 3 is heated by using a wide range of infrared heat, and in order to fully cure, the electrode 5 of the ceramic capacitor 4 and the terminal 7 of the minimold transistor 6 are bonded to the island 2. do.

After 1000 electronic components were attached to the printed circuit board, the location of these electronic components was checked by measurement.

As a result, no electronic components were found to be 0.3 mm or more away from their original positions.

Comparative Example 2

In FIG. 2, 1000 electronic components were attached onto the printed circuit board and the positions of these electronic components after the use of the adhesive composition (II) obtained in Comparative Example 1 were measured and inspected. As a result, there were five electronic components separated from this position by 0.3 mm or more.

Example 3

In using the adhesive composition obtained in Example 1, the ceramic capacitor 4 was installed on the printed circuit board 1 as in FIGS. 3 and 4a to 4d.

First, as shown in FIG. 4, the adhesive composition (I) (referred to as the adhesive composition 3 in this embodiment) was applied to the space between the islands 2 on the printed circuit board 1. In addition, the adhesive composition 3 was exposed to UV light in order to increase the viscosity.

The layer surface of the adhesive composition 3 becomes stronger than the inside while the adhesive remains. As shown in FIG. 4, the ceramic capacitor 4 is attached to the adhesive composition 3, and as shown in FIG. 4C, the surface of the printed circuit board 1 is taken along with the flow of the molten solder 8 therein. Next, as shown in FIG. 4D, the electrode 5 of the ceramic capacitor 4 is coupled to the island 2 of the printed circuit board 1 together with the solder 9.

Example 4

The adhesive composition (I) obtained in FIG. 1 is used for the ceramic capacitor 4 attached to the printed circuit board 1 by reflow as in FIGS. 5 and 6A to 6D.

First, as in FIG. 6, the solder paste 10 is applied to the island 2 of the printed circuit board 1 as a screen printing technique. Next, as shown in FIG. 6B, the adhesive composition (I) (referred to as the adhesive composition 3 in this embodiment) is applied to the space between the islands 2, and makes the viscosity more viscous by applying UV light. . The surface layer of the adhesive composition 3 is harder than the inside while the adhesive force remains. Therefore, as shown in FIG. 6C, the ceramic capacitor 4 is compressed on the upper portion of the adhesive composition 3 in order to fix the ceramic capacitor 4.

In addition, the printed circuit board 1 is heated using an air heating wind.

The solder paste 10 is then dissolved. As shown in FIG. 6D, the electrode 5 of the ceramic capacitor 4 is coupled to the island 2 of the printed circuit board 1 together with the solder 9. At this time, the adhesive composition 3 is completely cured by the heat generated from the reflow of the solder.

Example 5

The adhesive composition (I) obtained in Example 1 is used to attach an electronic component to a printed circuit board as shown in Figs. 11A and 11B.

First, as shown in FIG. 11A, the adhesive composition (I) (referred to as the adhesive composition 3 in this embodiment) is a printed circuit board by using the print head 100 as shown in FIG. 13 by a printing technique. The wiring pattern formed on ( ₁ ) is applied to the space between the islands 2 (the distance W ₁ between the spaces is 0.6 mm). The width of the applied adhesive composition 3 is 0.3 mm and the height is 0.2 mm.

In addition, the adhesive composition 3 was made more viscous by applying UV light to the surface of the printed circuit board to which the adhesive composition 3 was applied. As shown in FIG. 11, one of the electronic parts 4 is compressed onto the adhesive composition 3 to fix the electronic part 4. Expanding this process, the width of the adhesive composition 3 slightly increased compared with the original width, but the adhesive composition 3 was not in contact with the island 2. The electrode 5 of the electronic component 4 was in contact with the island 2. The shape of the adhesive composition 3 after application using the printing technique in this example is shown in Figure 7a. Not only the thickness W ₂ (= 0.3 mm) but also the height H ₂ (= 0.2 mm) also made it possible to accurately apply and adjust the adhesive composition 3.

The painting head 100 is used in this embodiment, which had a housing 11 containing an adhesive composition 3, the screw side 13 is supplied into the nozzle 12 of the housing 11, and the housing ( 11) An air pipe 16 is used to supply the air impregnated internally.

There is a helical pump consisting of the screw side 13 and the lower part of the nozzle 12. When the screw shaft 13 is rotated by the motor 14, the adhesive composition 3 proceeds to the outlet 15. The adhesive composition 3 flows out of the outlet 15 in the form of a line by the pressure of the compressed air by the movement of the air pipe 16 and the aforementioned helical pump.

Comparative Example 3

The adhesive composition (II) obtained in Example 1 entered the printhead 100 used in Example 5, but the viscosity of the adhesive composition (II) was too high and did not flow out into the outlet 15.

Example 6

Examples of the attachment of separate electronic components such as mini-mold transistors on the printed circuit board 1 using the adhesive composition (I) obtained in Example 1 are shown in FIGS. 12A and 12B. As shown in Fig. 12A, the two lines of the adhesive composition (I) (referred to as adhesive composition 3 in this example) are printed circuit boards 1 by the printing technique using the print head 100 shown in Fig. 5. It was applied to the space between the islands 2 of the wiring pattern formed thereon. The adhesive composition 3 can also make greater viscosity by applying UV light to the surface of the printed circuit board 1 to which the adhesive composition has been applied.

As shown in FIG. 12B, one of the electronic components 6 is positioned on the adhesive composition 3, and the leads 7 located at both the right and left sides of the electronic component 6 are formed on both sides of the electronic component 6. 2) Connected above. Even if the thickness d of the lid 7 is smaller than 0.2 mm, the reason why it is correctly connected to the island 2 is that the best adjustment applied to the adhesive composition 3 is possible.

Various other modifications are apparent to those skilled in the art and can be readily learned without departing from the scope and spirit of the invention. Accordingly, the appended claims are not intended to be limited to the description set forth, but rather to have the novelty features of the invention, including all features that would be equally handled by those skilled in the art to which the invention pertains. Should be interpreted.

Claims (8)

An adhesive composition for use in attaching an electronic component, wherein the adhesive composition comprises a photosetting and thermosetting resin component and a long chain saturated fatty acid amide. The adhesive composition according to claim 1, wherein the resin component is composed of a photosetting resin and a thermosetting resin. The adhesive composition according to claim 1, wherein the saturated fatty acid amide is prepared by reaction of saturated fatty acid having 9 to 12 carbon atoms having at least one tertiary amine. The adhesive composition according to claim 3, wherein the saturated fatty acid is steaamide. A method of attaching an electronic component on a printed circuit board, the method comprising: supplying the adhesive composition of claim 1 to a position on the printed circuit board to which the electronic component is attached, and wherein the surface layer of the composition is sufficient to fix the electronic component A printed circuit board comprising exposure to light to cure harder than inside to have adhesion, compressing the electronic component on the surface layer of the composition to attach the electronic component, and heating the composition to cure A method for attaching electronic components on a surface. The method of claim 5, wherein the composition is supplied by a printing technique such that the composition has a linear shape in a substantially rectangular shape in cross section. 6. The method of claim 5, further comprising coupling the electronic component onto a printed circuit board. 6. The method of claim 5, wherein said heating step of the composition is performed using heat generated at the time of bonding said electronic component on a printed circuit board.

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