JP3007490B2 - Cleaning method for electronic parts or precision parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning electronic parts or precision parts, and more particularly to electronic parts or precision parts to which contaminants such as oils and fats, machine oil, cutting oil, grease, liquid crystal and flux are adhered. A cleaning method.

[0002]

2. Description of the Related Art
Oils and fats on solid surfaces such as precision parts or tools
For removing dirt mainly composed of organic substances such as machine oil, cutting oil, grease, liquid crystal and flux, hydrocarbon solvents such as kerosene, benzene and xylene; chlorine solvents such as trichloroethylene and tetrachloroethylene; trichlorotrifluoroethane and the like A chlorofluorocarbon-based solvent; an aqueous cleaning solution containing a surfactant or a builder is used. In particular, fluorocarbon-based solvents or chlorine-based solvents have been used for components such as electronics, electricity, and machines, taking advantage of their high detergency and flame retardancy.

[0003] However, it has been revealed that cleaning solutions using the above-mentioned chlorinated solvents and chlorofluorocarbon-based solvents have serious problems in safety, toxicity, environmental pollution, etc., and their abolition has been promoted on an international level. I have.

[0004] From such a background, a solvent-based alternative cleaning solution such as a terpene-based solvent, a hydrocarbon-based solvent, or an alcohol-based solvent, or an aqueous-based cleaning solution containing a surfactant or the like, is used as a cleaning solution in place of a chlorine-based solvent or a fluorocarbon-based solvent. Cleaning methods using these cleaning liquids have been developed.These cleaning steps are usually performed by immersing the cleaning target in the cleaning liquid or spraying the cleaning liquid onto the cleaning target using a shower nozzle. And a rinsing step performed in the same manner.

As a cleaning method applied in the cleaning step or the rinsing step by immersing the object to be cleaned in a cleaning liquid, an ultrasonic vibration method, an oscillating method, a submerged shower method, a submerged rotation method, and the like are used. No. Further, as a cleaning method applied in a cleaning step or a rinsing step by spraying a cleaning liquid or a rinsing liquid onto the object to be cleaned using a shower nozzle, a method using a rotating nozzle as a shower nozzle and rotating the object to be cleaned are used. A method of injecting the cleaning liquid or the rinsing liquid onto the object to be cleaned while rinsing is used.

[0006] However, the ultrasonic vibration method has a problem that the object to be cleaned may be damaged, and the cleaning liquid is applied to the object to be cleaned using the swinging method, the submerged shower method, and the shower nozzle. The method by injecting into
This is effective when the object to be cleaned is a single object.However, when a plurality of objects to be cleaned are set in a jig, it is difficult to efficiently and uniformly clean all the objects to be cleaned. there were. In addition, the above-mentioned liquid rotation method (Japanese Utility Model Application Laid-Open No. 61-10913)
No. 6) is a relatively good means for solving the above problem, but also in this case, when a plurality of objects to be cleaned are set in the jig, the liquid between the objects to be cleaned rotates together. This makes it difficult for the liquid around the object to be renewed to be renewed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for cleaning a plurality of objects to be cleaned which can be simply and efficiently cleaned in a short time without damaging the objects to be cleaned. To provide.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, an object to be cleaned has been alternately passed through a liquid phase (cleaning liquid or rinsing liquid) and a gas phase in a cleaning tank. It has been found that by rotating the cleaning object, the liquid around the object to be cleaned is renewed reliably and efficiently, and a plurality of objects to be cleaned can be efficiently cleaned.

[0009] The present invention has been made based on the above findings, and is directed to a method for cleaning electronic parts or precision parts having one or more cleaning steps with a cleaning liquid and / or one or more rinsing steps with a rinsing liquid. A rotating shaft equipped with a jig for holding an object to be cleaned is disposed substantially horizontally with respect to the liquid phase in the cleaning tank, and the object to be cleaned is cleaned in the cleaning tank charged with the cleaning liquid or the rinsing liquid. An electronic component or a precision component, wherein the electronic component or the precision component is held by an object holding jig, and the object to be cleaned is washed by alternately and repeatedly passing through the liquid phase and the gas phase by rotating the rotating shaft. Cleaning methods are provided.

Hereinafter, the cleaning method of the present invention will be described in detail. The cleaning step in the cleaning method of the present invention is a step of performing cleaning with a cleaning liquid. The washing method in the washing step is not particularly limited, and includes an immersion method (a method of immersing an object to be cleaned in a washing tank), for example, an ultrasonic method, a rocking method, a submerged shower method, a submerged rotation method, and the like. Also, a shower method (a method of spraying a cleaning liquid onto an object to be cleaned using a shower nozzle), for example, a method using a rotating nozzle as a shower nozzle, or spraying a cleaning liquid onto an object to be cleaned while rotating the object to be cleaned The washing step is performed by appropriately combining them.

The rinsing step in the cleaning method of the present invention comprises:
This is a step of rinsing the cleaning liquid, contaminants, and the like remaining on the surface of the object to be cleaned with the rinsing liquid. The rinsing method in the rinsing step is not particularly limited, and includes, for example, a shower method, a dipping method, and the like, similar to the cleaning method in the cleaning step. The rinsing step is performed by appropriately combining these.

A cleaning apparatus used for carrying out the cleaning method of the present invention includes a cleaning tank charged with the cleaning liquid or the rinsing liquid, and a rotating shaft equipped with a jig for holding an object to be cleaned. And a washing device disposed substantially horizontally with respect to the cleaning device.

As the above-mentioned washing tank, there is a washing tank used in a washing step by an ordinary immersion method.

As the jig for holding the object to be cleaned, which is provided on the rotating shaft, the object to be cleaned is held, and the object to be cleaned is rotated between the liquid phase and the gas phase by rotating the rotating shaft. There is no particular limitation as long as it allows washing by passing alternately, but preferred examples include those shown in FIGS. 1 to 4.

A cleaning object holding jig 3 shown in FIG. 1 includes two holding rods 4 vertically fixed to a rotating shaft 2 and holding portions provided at the respective ends of the holding rods 4 for holding the cleaning object 1. 5, and the holding portion 5 includes a holding screw 6.
An appropriate number of the cleaning object holding jigs 3 can be provided around the rotation shaft 2 and in the axial direction. The holding rod 4 may be fixed substantially vertically to the rotating shaft 2 and may have a slight inclination. In the case of the object-to-be-cleaned jig shown in FIG. 1, the object to be cleaned 1 is held by the holding portion 5 by tightening the holding portion 5 with the holding screw 6.

The cleaning object holding jig 13 shown in FIG. 2 is perpendicular to the rotating shaft 2 and penetrates the rotating shaft 2 so that the rotating shaft 2
And a holding portion 15 provided outside the holding plate 14 for holding the object 1 to be cleaned. Note that the holding plate 14 may be substantially perpendicular to the rotation shaft 2 and may have a slight inclination. The holding portion 15 includes a fastener 16, a fastener fixing bar 17, and a fastener fixing screw 18, as shown in FIG.
The object to be cleaned 1 is held by the fastener 16, the fastener fixing bar 17, and the fastener fixing screw 18.
The cleaning object holding jig 13 can be provided in an appropriate number in the axial direction of the rotating shaft 2. In addition, the above-mentioned fastener 1
6 and the holding plate 14 are provided with a concave portion (not shown) corresponding to the shape of the object 1 to be cleaned in order to keep the object 1 to be cleaned in a contact portion with the object 1 to be cleaned. Is provided.
In the case of the cleaning object holding jig 13 shown in FIG. 2, the cleaning object 1 moves the fastener 16 toward the center of the rotation shaft 2, and moves the fastener 16 between the fastener 16 and the holding plate 14. It is gripped from both sides by tightening with the fastener fixing screw 18.

The jig 23 for holding an object to be cleaned shown in FIG. 3 is orthogonal to the rotating shaft 2 and penetrates the rotating shaft 2 so that the rotating shaft 2
And a holding portion 25 provided inside the holding plate 24 for holding the object 1 to be cleaned. Note that the holding plate 24 may be substantially perpendicular to the rotating shaft 2 and may have a slight inclination. As shown in FIG. 3, the holding portion 25 is provided inside the holding plate 24,
It is provided movably in accordance with the shape of the object 1 to be held. That is, the holding portion 25 fixes the radially outer side 25a of the rotary shaft 2 and makes the radially inner side 25b of the rotary shaft 2 movable, and tightens the object 1 to be cleaned using a spring (not shown). It has been done. Examples of the holding plate 24 include a disk, a rectangular plate, and a plate-like body having another shape. The jig 23 for holding an object to be cleaned may be provided in an appropriate number in the axial direction of the rotating shaft 2. it can. In the case of the cleaning object holding jig 23 shown in FIG.
Is fixedly held by the holding unit 25 at each vertex.

A jig 33 for holding an object to be cleaned shown in FIG.
Has a pair of holding plates 34 fitted to the intermittent portions at right angles to the rotating shaft 2 and two holding rods mounted between the holding plates 34, 34. The holding rod 35 is provided with a plurality of holding portions 36 for holding the object 1 to be cleaned, and the holding portion 36 is provided inside the holding rod 35 as shown in FIG. And a concave portion provided so as to fit the object 1 to be cleaned. The holding plate 3
4 may be substantially perpendicular to the rotation axis 2 and may have a slight inclination. Two of the holding rods 35 are mounted between the holding plates 34, 34, and a large number of the holding portions (recesses) 36 are provided in the axial direction of the rotating shaft 2. Further, the holding rod 35 is structured so as to be fastened toward the center of the rotary shaft 2 by a spring (not shown). Note that three or more holding rods 35 can be provided. In the case of the cleaning object holding jig 33 shown in FIG. 4A, the cleaning object 1 is inserted into the holding portions 36 of the two holding rods 35, and the holding rods 35 are moved from two ends toward the center. Is fixed by tightening it with a spring (not shown).

A jig 43 for holding an object to be cleaned shown in FIG. 4B is a pair of holding plates 44 which are orthogonal to the rotating shaft 2 and penetrate the rotating shaft 2 and are fitted to the rotating shaft 2. And four holding rods 45 mounted between the holding plates 44, 44. The holding rod 45 is provided with a plurality of holding portions 46 for holding the object 1 to be cleaned. As shown in FIG. 4 (b), it comprises a concave portion provided so that the object to be cleaned 1 is fitted inside the holding rod 45. The holding plate 44
May be substantially perpendicular to the rotation axis 2 and may have a slight inclination. The four holding rods 45 are mounted between the holding plates 44, 44, and a large number of the holding portions 46 (concave portions) are provided in the axial direction of the rotary shaft 2. The holding rod 45 has a structure in which the outside is fixed and the inside is tightened outward from the rotation shaft 2 by a spring (not shown). FIG.
In the cleaning object holding jig 43 shown in (b), two holding rods 45 are provided for the cleaning object 1, but three or more holding rods may be provided. In the case of the cleaning object holding jig 43 shown in FIG.
5 and is fixed by tightening the inside of the holding rod 45 outward with a spring (not shown).

As described above, the cleaning method of the present invention is particularly effective when a plurality of objects to be cleaned 1 are held along the axial direction of the rotary shaft 2 and a plurality of objects to be cleaned 1 are simultaneously cleaned. is there.

As a method of rotating the rotary shaft used in the present invention, a method of connecting one end of the rotary shaft to a rotary drive device using a motor or the like as a drive source can be used. In this case, it is preferable to hold the other end of the rotating shaft with a mechanism such as a bearing for stability.

The rotation speed of the rotating shaft varies depending on the size and shape of the object to be cleaned, but the speed (linear velocity) at the center of the object to be cleaned is preferably 0.1 m / s to 30 m / s.
s, more preferably 1 m / s to 30 m / s. If the velocity (linear velocity) at the center of the object to be cleaned is less than 0.1 m / s, the cleaning effect is small, and if it exceeds 30 m / s, there is a problem in operation and economical in terms of power. Disadvantageous.

The rotational speed may be determined not based on the center of the object to be cleaned, but on the position of the component if the component is mounted on a printed wiring board or the like. It may be set based on an appropriate part according to the purpose, such as based on a part to be dropped (for example, when the object to be cleaned is in the form shown in FIG. 4A).

The height of the liquid surface of the liquid phase in the cleaning tank is such that the object to be cleaned passes alternately through the liquid phase and the gas phase by rotating the rotating shaft. However, the vicinity of the rotation axis is desirable. Rotating the object to be cleaned in this manner is effective for improving the cleaning property and / or rinsing property and improving the processing capacity.

The direction of rotation of the rotating shaft may be only one direction, or may be reversed at predetermined time intervals, and may be appropriately selected depending on the shape of the object to be cleaned and the nature of dirt.

The washing solution used in the washing method of the present invention is not particularly limited, but a terpene solvent containing a terpene such as d-limonene obtained from animals and plants as an active ingredient,
Kerosene, benzene, hydrocarbon-based solvents containing hydrocarbons as active ingredients such as xylene, isopropyl alcohol, ethyl alcohol, solvent-based alternative cleaning liquids such as alcohol solvents containing lower alcohols such as methyl alcohol as active ingredients, surfactants, And an aqueous alternative washing liquid containing an alkaline agent such as sodium hydroxide and sodium orthosilicate, or a diluent thereof.

As the above-mentioned surfactant, anionic, cationic, amphoteric, nonionic surfactants and the like are used, but in consideration of the influence on members such as electronic parts, nonionic surfactants are preferable. Ether type such as alkyl ether type, alkyl allyl ether type and alkyl thioether type; ester type such as alkyl ester type and sorbitan alkyl ester type; condensed type with amine such as polyoxyalkylene alkylamine; polyoxyalkylene alkyl amide A polyurethane or tetronic type obtained by random or block condensation of polyoxyethylene and polyoxypropylene;
A surfactant such as a polyethyleneimine-based surfactant may be used. Among them, those having a hydrocarbon group having 4 to 22 carbon atoms are particularly preferable.

In the cleaning liquid composition containing a nonionic surfactant as described above, the rinse waste liquid after the rinsing mixed with the nonionic surfactant shows a clear cloud point, and removes oily stains and organic substances such as the cleaning liquid in the rinse waste liquid. Since it can be easily separated and removed, the load of wastewater treatment is reduced, and wastewater treatment properties are particularly good.

As the water-based alternative cleaning solution, a cleaning solution containing a surfactant and a compound selected from a hydrocarbon compound, a poorly water-soluble alkyl ester and an alkyl ketone can be used.

Examples of the hydrocarbon compound include paraffins, olefins, and aromatic hydrocarbons which are liquid at the temperature of the washing or rinsing step and have linear or branched saturated or unsaturated bonds having 6 to 30 carbon atoms. Hydrocarbon compounds including hydrogen and alicyclic hydrocarbons are exemplified. Examples of the alkyl esters include monoesters, diesters, and triesters having 6 to 40 carbon atoms which are liquid at the temperature of the washing or rinsing step, and particularly include 6 to 18 carbon atoms.
Esters of higher fatty acids and alcohols having 1 to 18 carbon atoms; esters of higher fatty acids having 6 to 18 carbon atoms and diols or triols having 2 to 8 carbon atoms; alcohols having 1 to 18 carbon atoms and 2 to 8 carbon atoms Esters with dicarboxylic or tricarboxylic acids are preferred. Further, as the alkyl ketones, dialkyl ketones having 6 to 40 carbon atoms are preferable.

As the cleaning liquid (cleaning liquid composition) used in the cleaning method of the present invention, a liquid containing a builder, a chelating agent, a rust preventive, an antifoaming agent and the like, if necessary, in addition to the above components, is used. Alternatively, two or more of the above compounds may be used in combination depending on the application.

In the case where the stain on the object to be washed is a stain having a property that can be removed with tap water, deionized water, pure water or the like, such water may be used as the washing liquid.

The rinsing liquid used in the cleaning method of the present invention is a liquid for rinsing dirt and / or a cleaning liquid composition on an object to be cleaned. The rinsing liquid is not particularly limited. For example, tap water, deionized water, pure water, or a liquid containing several percent of a cleaning liquid is used depending on the application. The rinsing liquid is discharged or reused after purifying. The above-mentioned purification treatment can be performed by a general wastewater treatment method such as coagulation sedimentation, pressure flotation, activated sludge, activated carbon, ion exchange, and a membrane treatment method alone or in an appropriate combination.

The electronic parts or precision parts to be cleaned according to the present invention include jigs (jigs) used for assembling, processing, or holding the electronic parts or precision parts during cleaning.
And the like.

Examples of the electronic component include a printed circuit board used for a computer and its peripheral devices, a home appliance, a communication device, an OA device, and other electronic applied devices;
Hoop materials used for contact members such as lead frames, resistors, capacitors, relays; Liquid crystal displays (liquid crystal display devices) used for OA equipment, clocks, computer equipment, toys, home appliances, etc .; Video / audio recording / reproduction parts And magnetic recording parts used for related parts; semiconductor materials such as silicon and ceramic wafers; parts for electrostriction such as quartz oscillators; photoelectric conversion parts used for CD, PD, copying equipment, optical recording equipment, etc. Is mentioned.

Examples of the precision parts include electric parts, precision machine parts, resin processed parts, and optical parts. Examples of the electric components include motor components such as brushes, rotors, stators, and housings; ticketing components used in vending machines and various devices; and currency inspection components used in vending machines and cash dispensers. Examples of the precision machine parts include bearings used for precision drive equipment, video recorders, and the like; machining parts such as carbide tips and the like. Examples of the resin processed parts include precision resin processed parts used for cameras, automobiles and the like. Further, examples of the optical components include lenses used for cameras, glasses, optical devices, and the like, and examples of the precision components include eyeglass frames, watch cases, watch belts, and the like.

As the above jigs and tools, there are electronic parts or precision parts as shown in the above-mentioned various parts.
In addition to jigs and tools handled in various processes for forming, processing, assembling, finishing, and the like, various devices handling these electronic components or precision components, components thereof, and the like are included.

The cleaning method of the present invention exhibits a suitable performance when cleaning liquid crystal and the like adhered to a printed wiring board or a glass substrate in which the flux remains, among the above electronic parts or precision parts. The electronic parts or precision parts to be covered by the present invention are not limited to these examples, but may be various processing oils, fluxes, and other interfering substances in the subsequent steps in the assembling processing step, or characteristics of the products. The cleaning method of the present invention can be applied to electronic parts or precision parts to which various types of oily contaminants that reduce the contamination are attached.

Further, in the cleaning method of the present invention, the contaminants may be, for example, oils and fats, machine oil, cutting oil, grease, liquid crystal,
In the case of mainly organic components such as rosin flux, the characteristics of the cleaning method of the present invention are particularly exhibited, and the present invention is effective even for contaminants in which metal powder, inorganic powder and the like are mixed.

Although the cleaning method of the present invention is not limited to the shape of the object to be cleaned as described above, it is particularly effective as a method for cleaning a plate-like body such as a printed wiring board.

Hereinafter, the cleaning method of the present invention will be described based on one embodiment. First, the object to be cleaned is held via the object to be cleaned holding jig provided on the rotating shaft as described above.
As the direction when holding the object to be cleaned by the object to be cleaned holding jig, usually, when the object to be cleaned is a plate, the surface of the plate is perpendicular to the rotation axis. Orientation. Next, the object to be cleaned is subjected to a cleaning process by a cleaning method in which the rotating shaft is rotated so that the object is alternately passed through a liquid phase and a gas phase, and then the object to be cleaned is immersed in the liquid phase. The liquid is drained by rotation without turning. Examples of a method for preventing the object to be cleaned from being immersed in the liquid phase include a method of moving the rotation drive device and the rotation axis of the rotating shaft upward, a method of removing the liquid phase from the bottom of the tank, and the like.

Next, after the rinsing step is performed in the same manner as the above-mentioned washing step, the liquid is removed by rotation without being immersed in the rinsing liquid. The rinsing step is usually performed one or more times, but may include only the washing step. Thus, draining by rotating the object to be cleaned in a state where it is not immersed in the liquid phase is effective in reducing the drainage load, and also effective in drying the object to be cleaned after the final rinsing. .

Further, in the cleaning method of the present invention, a well-known liquid drainage promoting method such as a method of blowing a gas such as air onto the object to be cleaned can be used together.

As a cleaning method other than the above-mentioned cleaning method for the electronic parts or precision parts of the present invention, the same cleaning method as a usual method can be appropriately adopted.

[0045]

In the case where the object to be cleaned is held by the jig for holding the object to be cleaned and the rotary shaft is rotated, the object to be cleaned is alternately passed through the liquid phase and the gaseous phase. When passing through the liquid surface of the liquid phase in the cleaning tank from the gas phase, a shear force acts on the object to be cleaned due to resistance from the liquid surface. This shearing force improves the cleaning effect or the rinsing effect. In addition, since the centrifugal force due to rotation acts on the contaminated substances and the remaining cleaning liquid on the object to be cleaned, the cleaning or rinsing is effectively performed even when components or the like are mounted on the object to be cleaned.

Next, when the object to be washed enters the gaseous phase from the liquid phase, a centrifugal force acts on the liquid (washing liquid or rinsing liquid) attached to the surface of the object to be cleaned. Flushing is performed by scattering from the surface of the cleaning object. Therefore, even if the liquid around the object to be cleaned remains on the surface of the object to be cleaned, the object to be cleaned is alternately passed through the liquid phase and the gaseous phase by rotation, whereby the surface of the object to be cleaned is rotated. Is separated from the object to be cleaned in the gas phase, so that when the object to be cleaned enters the liquid phase again, a new liquid exists around the object to be cleaned. Therefore, the liquid around the object to be cleaned is reliably and efficiently renewed.

As described above, in the cleaning method of the present invention, the object to be cleaned is washed by rotating the rotating shaft so as to alternately pass through the liquid phase and the gas phase.
Even when there are a plurality of objects to be cleaned and the holding interval is narrow, cleaning can be performed efficiently without lowering the cleaning performance and / or rinsing performance.

[0048]

Next, the cleaning method of the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

Example 1 A size of 30 mm × 50 mm and a thickness of 2 m as shown in FIG.
25mm × 25 on glass epoxy resin 51m
A glass 52 having a thickness of 1 mm and a thickness of 1 mm is fixed so that the central portion 53 of the glass is held at a single point on the glass epoxy resin with an adhesive so that the clearance becomes 100 μm. Flux 54
(Sample to be cleaned) 55 filled with (Nippon Solder RX363-207B extracted with tetrahydrofuran) was prepared.

The sample (the object to be cleaned) is held by a jig for holding the object to be cleaned as shown in FIG. 1 and held as shown in FIG. The height of the surface is set to a height in contact with the rotation axis, the object to be cleaned is set to be perpendicular to the liquid surface, and the rotation axis is set at 2 m / s at the center of the glass of the object to be cleaned. And washing was performed at 60 ° C. for 10 minutes. In addition, a mixture of 40 wt% of a nonionic surfactant, 40 wt% of C14 olefin, and 20 wt% of water was used as the cleaning liquid. The following Table 1 shows the flux removal rate of the washed sample.

Example 2 Cleaning was performed in the same manner as in Example 1 except that the distance between the objects to be cleaned (the distance along the rotation axis) was 9 mm. The following Table 1 shows the flux removal rate of the washed sample.

Example 3 Cleaning was performed in the same manner as in Example 1 except that the distance between the objects to be cleaned (the distance along the axis of the rotating shaft) was 14 mm. The following Table 1 shows the flux removal rate of the washed sample.

Comparative Example 1 A rotating shaft equipped with a jig for holding an object to be cleaned was arranged substantially perpendicular to the liquid phase in the cleaning tank so that the object to be cleaned was always present in the liquid. The cleaning was performed in the same manner as in Example 1. The following Table 1 shows the flux removal rate of the washed sample.

Comparative Example 2 Cleaning was performed in the same manner as in Comparative Example 1 except that the distance between the objects to be cleaned (the distance along the axis of the rotating shaft) was 9 mm. The following Table 1 shows the flux removal rate of the washed sample.

Comparative Example 3 Cleaning was performed in the same manner as in Comparative Example 1, except that the distance between the objects to be cleaned (the distance along the axis of the rotating shaft) was 14 mm. The following Table 1 shows the flux removal rate of the washed sample.

FIG. 6 is a graph showing the dependence of the flux removal rate on the distance between the objects to be cleaned in Examples 1 to 3 and Comparative Examples 1 to 3.

Example 4 Size of 140 mm × 100 with the rotation axis passing perpendicularly to the center
A sample (substrate to be cleaned) similar to that of Example 1 was held on a glass epoxy resin holding plate having a thickness of 2 mm and a thickness of 2 mm as shown in FIG. 3, and the distance between the holding plates (along the rotation axis). Direction is set to 5 mm, the height of the liquid surface of the liquid phase in the cleaning tank is set to a height in contact with the rotating shaft, and the rotating shaft is set at the glass center point (glass and glass epoxy resin) of the object to be cleaned. Adhesive part)
The cleaning was performed at 60 ° C. for 10 minutes while rotating at a speed (linear speed) of 2 m / s. As a cleaning solution,
The same one as in Example 1 was used. The removal rate of the flux in the sample after washing is shown in the following [Table 1].

Example 5 Cleaning was carried out in the same manner as in Example 4, except that the distance between the objects to be cleaned (the distance along the axis of the rotating shaft) was 9 mm. The following Table 1 shows the flux removal rate of the washed sample.

Example 6 Cleaning was carried out in the same manner as in Example 4, except that the distance between the objects to be cleaned (the distance along the axis of the rotating shaft) was 14 mm. The following Table 1 shows the flux removal rate of the washed sample.

COMPARATIVE EXAMPLE 4 A rotating shaft equipped with a jig for holding an object to be cleaned was arranged substantially perpendicular to the liquid phase in the cleaning tank so that the object to be cleaned was always present in the liquid. Was washed in the same manner as in Example 4. The following Table 1 shows the flux removal rate of the washed sample.

Comparative Example 5 Cleaning was carried out in the same manner as in Comparative Example 4, except that the distance between the objects to be cleaned (the distance along the axis of the rotating shaft) was 9 mm. The following Table 1 shows the flux removal rate of the washed sample.

Comparative Example 6 Cleaning was performed in the same manner as in Comparative Example 4, except that the distance between the objects to be cleaned (the distance along the axis of the rotating shaft) was 14 mm. The following Table 1 shows the flux removal rate of the washed sample.

FIG. 7 is a graph showing the dependence of the flux removal rate on the distance between the objects to be cleaned in Examples 4 to 6 and Comparative Examples 4 to 6.

Example 7 A sample similar to that of Example 1 was held as shown in FIG. 4A by a jig for holding an object to be cleaned as shown in FIG. The height of the liquid surface of the liquid phase in the cleaning tank is set to a height in contact with the rotating shaft, and the rotating shaft is set at the glass center point (glass) of the object to be cleaned. At a temperature of 60 ° C. and at a speed (linear velocity) of 2 m / s.
Washing was performed for minutes. The removal rate of the flux in the sample after washing is shown in the following [Table 1].

Example 8 Cleaning was performed in the same manner as in Example 7, except that the distance between the objects to be cleaned was 9 mm. The following Table 1 shows the flux removal rate of the washed sample.

Example 9 Cleaning was performed in the same manner as in Example 7, except that the distance between the objects to be cleaned was 14 mm. The following Table 1 shows the flux removal rate of the washed sample.

COMPARATIVE EXAMPLE 7 A rotating shaft equipped with a jig for holding an object to be cleaned was disposed substantially perpendicular to the liquid phase in the cleaning tank, so that the object to be cleaned was always present in the liquid. Was washed in the same manner as in Example 7. The following Table 1 shows the flux removal rate of the washed sample.

Comparative Example 8 Cleaning was performed in the same manner as in Comparative Example 7, except that the distance between the objects to be cleaned was 9 mm. The following Table 1 shows the flux removal rate of the washed sample.

Comparative Example 9 Cleaning was performed in the same manner as in Comparative Example 7, except that the distance between the objects to be cleaned was 14 mm. The following Table 1 shows the flux removal rate of the washed sample.

FIG. 8 is a graph showing the dependence of the flux removal rate on the distance between the objects to be cleaned in Examples 7 to 9 and Comparative Examples 7 to 9.

[0071]

[Table 1]

The flux removal rate was calculated as the ratio of the area of the flux-removed portion after cleaning to the area of the flux-filled portion before cleaning.

As can be seen from Table 1 and FIGS. 6 to 8, the fluxes of Examples 1 to 9 are higher than those of Comparative Examples 1 to 9 in which the object to be cleaned is rotated while being constantly immersed in the liquid. Large removal rate. Therefore, Examples 1 to 9 are comparative examples 1 to 9.
The cleaning performance is higher than that of the above, and even when the object to be cleaned or the spacing between the holding plates is narrow, the cleaning performance does not decrease due to the co-rotation of the liquid. For this reason, according to the cleaning method of the present invention, the time is reduced by the high cleaning property, and the number of objects to be cleaned that can be processed in the same space can be increased, so that an improvement in productivity can be expected.

Example 10 A printed wiring board treated with a rosin flux having a size of 140 mm × 100 mm was held as shown in FIG. 1 by a jig for holding an object to be washed shown in FIG. The process was performed. Next, using tap water as a rinsing liquid, a rinsing step (preliminary rinsing) in the same manner as the washing step.
And finally, a rinsing step (finish rinsing) was performed in the same manner as the washing step using pure water as a rinsing liquid.
Then, to examine the effect of washing, MIL-P-288 was used.
09, and the omegameter (Japan α
As a result of measuring the ion residue using a metal (600R-SC), the measured value was 0.5 μg / in ² , and the cleaning method of the present invention showed that the allowable value of the ion residue was 14 μg.
It was found that good detergency to clear / in ² was exhibited.

[0075]

According to the method for cleaning electronic parts or precision parts of the present invention, dirt on the object to be cleaned can be easily and efficiently removed in a short time, and a large number of objects to be cleaned can be processed. It is. Furthermore, since the liquid is drained efficiently and simply in the washing step or the rinsing step, the amount of the detergent used, the drainage load and the drying time can be reduced.
Therefore, economical and highly productive cleaning can be performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a cleaning object holding jig including a holding rod fixed vertically to a rotation shaft and a holding portion provided at a tip of the holding rod and holding the cleaning object. FIG.

FIG. 2 is a view showing a holding plate which is orthogonal to the rotating shaft and penetrates the rotating shaft and is fitted to the rotating shaft and a holding member provided outside the holding plate for holding the object to be cleaned; FIG. 6 is a perspective view showing an example of a jig for holding an object to be cleaned, comprising:

FIG. 3 is a view showing a holding plate which is orthogonal to the rotating shaft and penetrates the rotating shaft and is fitted to the rotating shaft and a holding member provided inside the holding plate for holding the object to be cleaned; FIG. 6 is a perspective view showing an example of a jig for holding an object to be cleaned, comprising:

FIG. 4 (a) shows a pair of holding plates which are fitted to intermittent portions of the rotating shaft at right angles to the rotating shaft when the rotating shaft is intermittent, and which are mounted between the holding plates. FIG. 5 is a perspective view showing an example of a jig for holding an object to be cleaned which includes a plurality of holding rods provided and a plurality of holding portions for holding the object to be cleaned provided on the holding rod. FIG. 4 (b) includes a pair of holding plates that are orthogonal to the rotating shaft and penetrate the rotating shaft and fitted to the rotating shaft, and a plurality of holding rods mounted between the holding plates. FIG. 4 is a perspective view showing an example of a jig for holding an object to be cleaned, in which the holding rod is provided with a plurality of holding portions for holding the object to be cleaned.

FIG. 5 (a) shows Examples 1 to 9 and Comparative Examples 1 to 9
FIG. 5B is a plan view showing the sample used in FIG. 5, and FIG. 5B is a side view thereof.

FIG. 6 is a graph showing the dependence of the flux removal rate on the distance between objects to be cleaned in Examples 1 to 3 and Comparative Examples 1 to 3.

FIG. 7 is a graph showing the dependence of the flux removal rate on the spacing between holding plates in Examples 4 to 6 and Comparative Examples 4 to 6.

FIG. 8 is a graph showing the dependence of the flux removal rate on the distance between objects to be cleaned in Examples 7 to 9 and Comparative Examples 7 to 9.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 To-be-cleaned object 2 Rotation axis 3 To-be-cleaned object holding jig 4 Holding rod 5 Holding part 6 Nipping screw 13 To-be-cleaned object holding jig 14 Holding plate 15 Holding part 16 Fastening 17 Fastening fixing rod 18 Fastening fixing screw 23 Cleaning object holding jig 24 Holding plate 25a holding section 25b holding section 33 Cleaning object holding jig 34 Holding plate 35 Holding rod 36 Holding section 43 Cleaning object holding jig 44 Holding plate 45 Holding rod 46 Holding section 51 Glass Epoxy resin 52 Glass 53 Central part 54 Flux 55 Sample

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-48-27876 (JP, A) JP-A-4-197478 (JP, A) JP-A-63-221625 (JP, A) 191188 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B08B 3/04-3/12 H05K 3/26 H01L 21/304

Claims (6)

(57) [Claims] 1. One or more cleaning steps with a cleaning liquid and / or
Or a method of cleaning electronic components or precision parts having one or more rinsing steps with a rinsing liquid, wherein the cleaning liquid or the cleaning tank charged with the rinsing liquid includes a rotating shaft equipped with a jig for holding an object to be cleaned. The cleaning object is disposed substantially horizontally with respect to the liquid phase in the cleaning tank, the object to be cleaned is held by the jig for holding the object to be cleaned, and the object to be cleaned is separated from the liquid phase by rotating the rotating shaft. A method for cleaning electronic parts or precision parts, characterized by alternately and repeatedly passing through a gaseous phase for cleaning. 2. The object-to-be-cleaned holding jig comprises a holding rod vertically fixed to the rotating shaft and a holding portion provided at a tip of the holding rod and holding the object to be cleaned. The method for cleaning electronic parts or precision parts according to claim 1. 3. The holding jig for holding an object to be cleaned is provided at right angles to the rotation axis and through the rotation axis so as to be fitted to the rotation axis and inside or outside the holding plate. The method for cleaning electronic components or precision components according to claim 1, further comprising a holding unit that holds the object to be cleaned. 4. The jig for holding an object to be cleaned comprises a pair of holding plates fitted perpendicularly to the rotation axis and a plurality of holding bars mounted between the holding plates. 2. The method for cleaning electronic parts or precision parts according to claim 1, further comprising a plurality of holding portions for holding the object to be cleaned. 5. The method for cleaning electronic components or precision components according to claim 1, wherein the object to be cleaned is a plate. 6. The method for cleaning electronic parts or precision parts according to claim 5, wherein the plate is a printed wiring board.