JP2015170843A - Chip electronic component and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip electronic component improved in magnetic powder dispersibility and sedimentation stability by applying a new type of dispersant, and a manufacturing method thereof.SOLUTION: A magnetic substance main body contains an unsaturated carboxylic acid based polymer and also a siloxane-based copolymer, and thus realizes improved dispersibility of magnetic powder, thereby having an improved filling factor of 80% or more and improved inductance capacity characteristics.

Description

The present invention relates to a chip electronic component and a manufacturing method thereof.

An inductor, which is one of chip electronic components, is a typical passive element that forms an electronic circuit together with a resistor and a capacitor to remove noise, and is combined with a capacitor using electromagnetic characteristics. Therefore, it is used for a configuration of a resonance circuit, a filter circuit, or the like that amplifies a signal in a specific frequency band.

Recently, IT devices such as various communication devices or display devices have been miniaturized and thinned, and various elements such as inductors, capacitors, and transistors used in the IT devices are also miniaturized and thinned. Research is ongoing.

Further, as electronic devices are required to be smaller and have higher performance, power consumption is increasing. With such an increase in power consumption, a switching frequency (Switching Frequency) of a PMIC (Power Management Integrated Circuit) or a DC-DC converter (DC-DC Converter) used in a power supply circuit of an electronic device is increased, and an output current is increased. Therefore, the use of power inductors used to stabilize the output current of the PMIC or DC-DC converter tends to increase.

The development direction of power inductors is tailored to miniaturization, high current, and low DC resistance. However, since conventional multilayer power inductors have limitations in realizing this, plating on the upper and lower surfaces of the insulating substrate Thin film inductors are being developed that are manufactured by stacking, pressing and curing a magnetic sheet formed by mixing magnetic powder with resin on a coil pattern to be formed.

At this time, the slurry (Slurry) forming the magnetic sheet is made of a magnetic powder, a thermosetting polymer resin, a curing agent, a thickening agent, an organic solvent, a dispersant capable of improving the dispersibility of the powder, and the like.

In order to disperse the magnetic powder more efficiently, not only chemical dispersion using a dispersing agent but also mechanical force may be applied in specific equipment.

In order to realize a higher function, the magnetic powder is gradually reduced in size and atomized, and two or more kinds of powders having different sizes are mixed and used. Therefore, since dispersion of magnetic powder becomes more difficult, a method capable of realizing more effective dispersibility is demanded.

Conventionally, a phosphoric acid-based dispersant composed of a polymer having a weight average molecular weight of 700 to 2,500 is used. However, the sedimentation stability of a high-density metal magnetic powder is maintained, and the powders are re-aggregated after primary dispersion. In order to prevent secondary agglomeration, there is a drawback that the dispersion force is insufficient.

Korean Published Patent No. 2013-0072816 JP 2008-166455 A

One embodiment of the present invention relates to a chip electronic component that improves the dispersibility and sedimentation stability of a magnetic powder by applying a new type of dispersant, and a method for manufacturing the same.

In one embodiment of the present invention, a magnetic body including an internal coil pattern formed on at least one surface of an insulating substrate, and formed on at least one end surface of the magnetic body and connected to an end of the internal coil pattern. The magnetic body includes a chip electronic component including an unsaturated carboxylic acid polymer.

The magnetic body may further include a siloxane copolymer.

The magnetic body may include a metallic soft magnetic material.

The particle size of the metal-based soft magnetic material may be 0.1 μm to 30 μm.

The unsaturated carboxylic acid polymer may have a weight average molecular weight of 500 to 2,300.

The siloxane-based copolymer may have a weight average molecular weight of 500 to 2,300.

The unsaturated carboxylic acid polymer may be included in an amount of 0.5 to 2 parts by weight with respect to 100 parts by weight of the metal soft magnetic material included in the magnetic body.

The siloxane-based copolymer may be included in an amount of 0.05 to 0.2 parts by weight with respect to 100 parts by weight of the metal-based soft magnetic material included in the magnetic body.

The filling factor of the magnetic body may be 80% or more.

In another embodiment of the present invention, a magnetic body is formed by forming an internal coil pattern on at least one surface of an insulating substrate, and laminating magnetic sheets on an upper portion and a lower portion of the insulating substrate on which the internal coil pattern is formed. And forming an external electrode on at least one end surface of the magnetic body so as to be connected to an end of the internal coil pattern, and the magnetic sheet is made of an unsaturated carboxylic acid based weight. Provided is a method of manufacturing a chip electronic component formed including a united body.

The magnetic sheet may further include a siloxane copolymer.

The magnetic sheet may be formed including a metallic soft magnetic material.

The particle size of the metal-based soft magnetic material may be 0.1 μm to 30 μm.

The unsaturated carboxylic acid polymer may have a weight average molecular weight of 500 to 2,300.

The siloxane-based copolymer may have a weight average molecular weight of 500 to 2,300.

The magnetic sheet may include 0.5 to 2 parts by weight of the unsaturated carboxylic acid polymer with respect to 100 parts by weight of the metallic soft magnetic material included in the magnetic sheet.

The magnetic sheet may include 0.05 to 0.2 parts by weight of the siloxane copolymer with respect to 100 parts by weight of the metal soft magnetic material included in the magnetic sheet.

The filling factor of the magnetic body may be 80% or more.

According to one embodiment of the present invention, excellent dispersion characteristics and anti-settling effect of the magnetic powder can be obtained at the same time.

In addition, the magnetic powder sheet surface roughness can be reduced by implementing the improvement of slip property and leveling property of the magnetic powder and the effect of preventing the Benard cell phenomenon.

In addition, as the dispersibility of the magnetic powder is improved, the filling rate is improved and the inductance capacity is improved.

1 is a schematic perspective view illustrating an internal coil pattern of a chip electronic component according to an embodiment of the present invention. It is sectional drawing by the I-I 'line | wire of FIG. In order to compare the filling rate of a magnetic sheet (a) manufactured using a conventional dispersant and a magnetic sheet (b) used in manufacturing a chip electronic component according to an embodiment of the present invention, a scanning electron microscope ( It is the photograph which observed the cross section of the magnetic material sheet by SEM and Scanning Electron Microscope. It is the graph which showed the inductance of the chip electronic component (c) manufactured using the conventional dispersing agent, and the chip electronic component (d) by one Embodiment of this invention. It is process drawing which shows the manufacturing method of the chip electronic component by one Embodiment of this invention. Comparison was made between the settling stability of a slurry (e) using a conventional dispersant (e) and a slurry (slurry) (f) forming a magnetic sheet used in the manufacture of a chip electronic component according to an embodiment of the present invention. It is a graph. In order to compare the surface roughness of a magnetic sheet (g) manufactured using a conventional dispersant and the magnetic sheet (h) used in manufacturing a chip electronic component according to an embodiment of the present invention, scanning electrons are compared. It is the photograph which observed the surface of the magnetic material sheet with the microscope (SEM, Scanning Electron Microscope).

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. The shape and size of elements in the drawings may be exaggerated for a clearer description.

Hereinafter, the chip electronic component according to the embodiment of the present invention will be described using a thin film inductor, but the present invention is not limited thereto.

FIG. 1 is a schematic perspective view illustrating an internal coil pattern of a chip electronic component according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line I-I 'of FIG.

Referring to FIGS. 1 and 2, a thin film inductor 100 used for a power supply line of a power supply circuit is disclosed as an example of a chip electronic component. In addition to the chip inductor, the chip electronic component may be a chip bead, a chip filter, or the like.

The thin film inductor 100 includes a magnetic body 50, an insulating substrate 20, an internal coil pattern 40, and an external electrode 80.

The magnetic body 50 forms the appearance of the thin film inductor 100 and may be hexahedral. In order to clearly describe the embodiment of the present invention, if the direction of a hexahedron is defined, L, W, and T shown in FIG. 1 indicate a length direction, a width direction, and a thickness direction, respectively. The magnetic body 50 may have a rectangular parallelepiped shape in which the length direction is longer than the width direction.

The magnetic body 50 can be formed by laminating magnetic sheets made of sheet containing magnetic powder, press-bonding and curing.

As the magnetic powder constituting the magnetic body 50, a metallic soft magnetic material may be used.

The metallic soft magnetic material may be an alloy containing at least one selected from the group consisting of Fe, Si, Cr, Al, and Ni. Crystalline metal particles can be included, but are not limited thereto.

The metal-based soft magnetic material may have a particle size of 0.1 μm to 30 μm, and may be included in a dispersed form on a polymer such as an epoxy resin or a polyimide.

The magnetic body 50 may contain an unsaturated carboxylic acid polymer as a dispersant for improving the dispersibility of the magnetic powder.

Conventionally, in order to disperse the magnetic powder constituting the magnetic body of the thin film type inductor, a phosphoric acid polymer dispersant having a weight average molecular weight of 700 to 2,500 has been mainly used, but there is a limit to improving the dispersibility. was there. In particular, in the case of a thin film type inductor using a metal magnetic powder having a high density, it is difficult to maintain sedimentation stability and realize excellent dispersibility.

Therefore, in one embodiment of the present invention, an unsaturated carboxylic acid polymer is newly applied as a fatty acid dispersant to significantly improve the dispersibility of the metal magnetic powder constituting the magnetic body of the thin film inductor.

The magnetic body may further include a siloxane copolymer.

By further including a siloxane-based copolymer, it is possible to realize both the slip property of the magnetic powder, the improvement of the leveling property, and the effect of preventing the Benard cell phenomenon.

The unsaturated carboxylic acid polymer may have a weight average molecular weight of 500 to 2,300.

The unsaturated carboxylic acid polymer may be included in an amount of 0.5 to 2 parts by weight with respect to 100 parts by weight of the metallic soft magnetic material included in the magnetic body 50.

If the unsaturated carboxylic acid polymer is less than 0.5 part by weight, the dispersibility and sedimentation stability are reduced and the magnetic powder is agglomerated, so the filling rate is reduced and the surface roughness of the magnetic material sheet is increased. If the amount exceeds 2 parts by weight, the solvent volatilization passage is not secured when the magnetic sheet is dried or cured, and the solvent may be trapped inside and the physical properties may be deteriorated.

The siloxane-based copolymer may have a weight average molecular weight of 500 to 2,300.

The siloxane copolymer may be included in an amount of 0.05 part by weight to 0.2 part by weight with respect to 100 parts by weight of the metal soft magnetic material included in the magnetic body 50.

When the siloxane-based copolymer is less than 0.05 parts by weight, the magnetic powder has little improvement in slipping and leveling characteristics and the effect of preventing the Benard cell phenomenon, and the surface roughness of the magnetic material sheet is small. If the amount exceeds 0.2 parts by weight, there is a risk that the solvent will be trapped inside and the physical properties may be deteriorated because the solvent volatilization passage is not secured when the magnetic sheet is dried or cured. is there.

As described above, the magnetic body 50 of the chip electronic component according to the embodiment of the present invention includes the unsaturated carboxylic acid polymer, and further includes the siloxane copolymer, thereby improving the dispersibility of the magnetic powder. Thus, the filling rate can be improved and the inductance capacity characteristics can be improved.

The filling rate of the magnetic body 50 may be 80% or more.

FIG. 3 shows a magnetic sheet (a) produced using ethoxylated nonylphenol phosphate, which is a conventional phosphoric acid polymer dispersant, and an unsaturated carboxylic acid according to an embodiment of the present invention. It is the photograph which observed the cross section of the magnetic material sheet (b) manufactured by adding a styrene polymer and a siloxane copolymer as a dispersing agent with a scanning electron microscope (SEM).

From FIG. 3, when a magnetic sheet is produced by adding an unsaturated carboxylic acid polymer and a siloxane copolymer according to one embodiment of the present invention, the dispersibility of the magnetic powder is improved and the filling rate is improved. I understand that. In the conventional case (a), the filling rate is 77.09%, but in the case of one embodiment of the present invention (b), the filling rate is improved to 87.40%.

FIG. 4 shows a chip electronic component (c) including an ethoxylated nonylphenol phosphate, which is a conventional phosphoric acid polymer dispersant, and an unsaturated carboxylic acid polymer according to an embodiment of the present invention. It is the graph which showed the inductance of the chip electronic component (d) containing a siloxane copolymer.

Referring to FIG. 4, it can be seen that the inclusion of an unsaturated carboxylic acid polymer and a siloxane copolymer according to an embodiment of the present invention improves the inductance as the dispersibility and packing ratio of the magnetic powder is improved. .

The insulating substrate 20 formed inside the magnetic body 50 may be formed of, for example, a polypropylene glycol (PPG) substrate, a ferrite substrate, or a metal soft magnetic substrate.

A hole is formed through the central portion of the insulating substrate 20, and the through hole is filled with a magnetic material such as a metallic soft magnetic material to form the core portion 55. By forming the core portion 55 filled with a magnetic material, inductance (Inductance, L) can be improved.

An inner coil pattern 40 having a coiled pattern may be formed on one surface of the insulating substrate 20, and a coiled pattern of the inner coil pattern 40 may be formed on the opposite surface of the insulating substrate 20.

The internal coil pattern 40 may be formed in a spiral shape, and the internal coil pattern 40 formed on the surface opposite to the one surface of the insulating substrate 20 is a via formed in the insulating substrate 20. It can be electrically connected through the electrode 45.

The internal coil pattern 40 and the via electrode 45 may include a metal having excellent electrical conductivity. For example, silver (Ag), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), copper (Cu), platinum (Pt), or an alloy thereof may be used.

An insulating film 30 that covers the internal coil pattern 40 may be formed on the surface of the internal coil pattern 40.

The insulating film 30 may be formed by a known method such as a screen printing method, a process through exposure and development of a photoresist (PR), and a spray coating process, but is not limited thereto.

One end portion of the internal coil pattern 40 formed on one surface of the insulating substrate 20 can be exposed in one longitudinal section of the magnetic body 50, and the internal coil pattern 40 formed on the opposite surface of the insulating substrate 20. The other end of the magnetic body 50 can be exposed at the other end surface of the magnetic body 50 in the length direction.

External electrodes 80 may be formed on both end surfaces of the magnetic body 50 so as to be connected to the lead portions of the internal coil pattern 40 exposed on both end surfaces of the magnetic body 50.

The external electrodes 80 may be formed on both end faces in the length direction of the magnetic body 50 and extended on both end faces in the thickness direction and / or both end faces in the width direction of the magnetic body 50.

The external electrode 80 may be formed to include a metal having excellent electrical conductivity, for example, nickel (Ni), copper (Cu), tin (Sn), silver (Ag) or the like alone or an alloy thereof. Can be formed.

Chip Electronic Component Manufacturing Method FIG. 5 is a process diagram illustrating a chip electronic component manufacturing method according to an embodiment of the present invention.

Referring to FIG. 5, the internal coil pattern 40 may be formed on at least one surface of the insulating substrate 20.

The insulating substrate 20 is not particularly limited, and for example, a polypropylene glycol (PPG) substrate, a ferrite substrate, a metal soft magnetic substrate, or the like can be used, and the thickness may be 40 to 100 μm.

The internal coil pattern 40 may be formed by, for example, an electroplating method, but is not limited thereto, and the internal coil pattern 40 may be formed to include a metal having excellent electrical conductivity. , Silver (Ag), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), copper (Cu), platinum (Pt), or an alloy thereof may be used. it can.

A via electrode 45 can be formed by forming a hole in a part of the insulating substrate 20 and filling with a conductive material, and an internal portion formed on the surface opposite to the one surface of the insulating substrate 20 via the via electrode 45. The coil part 40 can be electrically connected.

A through-hole penetrating the insulating substrate may be formed in the central portion of the insulating substrate 20 by drilling, laser, sandblasting, drilling, or the like.

Next, the insulating film 30 covering the internal coil pattern 40 can be formed.

The insulating film 30 may be formed by a known method such as a screen printing method, a photo resist (PR) exposure and development process, or a spray coating process, but is not limited thereto.

Next, the magnetic body 50 is formed by laminating magnetic sheets on the upper and lower portions of the insulating substrate 20 on which the internal coil pattern 40 is formed.

A metal-based soft magnetic material can be used as the magnetic powder used for manufacturing the magnetic sheet.

The metal-based soft magnetic material may be an alloy containing any one or more selected from the group consisting of Fe, Si, Cr, Al, and Ni. For example, an Fe-Si-B-Cr-based amorphous material However, the present invention is not limited to this.

The particle size of the metallic soft magnetic material may be 0.1 μm to 30 μm.

Applying and drying a slurry formed by mixing the metal-based soft magnetic material and a polymer such as epoxy resin or polyimide onto a carrier film to produce a magnetic sheet. Can do.

At this time, an unsaturated carboxylic acid polymer may be included as a dispersant for effectively dispersing the magnetic powder on the polymer.

The magnetic sheet may further contain a siloxane copolymer.

By further including a siloxane-based copolymer, it is possible to realize both the slip property of the magnetic powder, the improvement of the leveling property, and the effect of preventing the Benard cell phenomenon.

The unsaturated carboxylic acid polymer may have a weight average molecular weight of 500 to 2,300.

The unsaturated carboxylic acid polymer may be included in an amount of 0.5 to 2 parts by weight with respect to 100 parts by weight of the metallic soft magnetic material included in the magnetic sheet.

If the unsaturated carboxylic acid polymer is less than 0.5 part by weight, the dispersibility and sedimentation stability are reduced and the magnetic powder is agglomerated, so the filling rate is reduced and the surface roughness of the magnetic material sheet is increased. If the amount exceeds 2 parts by weight, the solvent volatilization passage is not secured when the magnetic sheet is dried or cured, and the solvent may be trapped inside and the physical properties may be deteriorated.

The siloxane-based copolymer may have a weight average molecular weight of 500 to 2,300.

The siloxane copolymer may be included in an amount of 0.05 part by weight to 0.2 part by weight with respect to 100 parts by weight of the metal soft magnetic material contained in the magnetic sheet.

When the siloxane-based copolymer is less than 0.05 parts by weight, the magnetic powder has little improvement in slipping and leveling characteristics and the effect of preventing the Benard cell phenomenon, and the surface roughness of the magnetic material sheet is small. If the amount exceeds 0.2 parts by weight, there is a risk that the solvent will be trapped inside and the physical properties may be deteriorated because the solvent volatilization passage is not secured when the magnetic sheet is dried or cured. is there.

FIG. 6 shows a slurry (e) of metal magnetic powder produced by adding ethoxylated nonylphenol phosphate, which is a conventional phosphoric acid polymer dispersant, and one embodiment of the present invention. It is the graph which compared the sedimentation stability of the slurry (slurry) (f) of the metal magnetic powder manufactured by adding unsaturated carboxylic acid type polymer and siloxane type copolymer as a dispersing agent according to a form.

From FIG. 6, when an unsaturated carboxylic acid polymer and a siloxane copolymer are included according to one embodiment of the present invention, the rate of decrease in the height of the sedimentation layer over time is greatly reduced, and sedimentation stability is improved. I understand that.

FIG. 7 shows a magnetic sheet (g) produced using ethoxylated nonylphenol phosphate, which is a conventional phosphoric acid polymer dispersant, and an unsaturated carboxylic acid according to an embodiment of the present invention. It is the photograph which observed the surface of the magnetic material sheet (h) manufactured by adding an acid type polymer and a siloxane type copolymer as a dispersing agent with a scanning electron microscope (SEM).

From FIG. 7, the magnetic material sheet (g) produced by adding an unsaturated carboxylic acid polymer and a siloxane copolymer according to one embodiment of the present invention is a magnetic material produced by adding a conventional dispersant. Compared with the sheet (h), the dispersibility is improved, and the surface roughness is reduced due to the leveling effect and the Benard cell phenomenon prevention effect.

As described above, the magnetic sheet manufactured according to the embodiment of the present invention includes an unsaturated carboxylic acid polymer, and further includes a siloxane copolymer, thereby improving the dispersibility of the magnetic powder. Thus, the filling rate can be improved and the inductance capacity characteristics can be improved.

The filling rate of the magnetic body 50 according to an embodiment of the present invention manufactured using the magnetic sheet may be 80% or more.

The magnetic body main body 50 can be formed by laminating the magnetic sheet on both surfaces of the insulating substrate 20 and press-bonding them by a laminating method or an isostatic pressing method. At this time, the core portion 55 can be formed so that the through hole is filled with a magnetic material.

Next, the external electrode 80 can be formed on at least one end surface of the magnetic body 50 so as to be connected to the lead portion of the internal coil pattern 40 exposed in at least one section of the magnetic body 50.

The external electrode 80 can be formed using a paste containing a metal having excellent electrical conductivity. For example, nickel (Ni), copper (Cu), tin (Sn) or silver (Ag) alone or A conductive paste containing these alloys may also be used.

The external electrode 80 may be formed not only by printing along the shape of the external electrode 80 but also by a dipping method or the like.

The description of the same parts as those of the chip electronic component according to the embodiment of the present invention described above is omitted.

The embodiment of the present invention has been described in detail above, but the scope of the present invention is not limited to this, and various modifications and variations can be made without departing from the technical idea of the present invention described in the claims. It will be apparent to those having ordinary knowledge in the art.

DESCRIPTION OF SYMBOLS 100 Thin film type inductor 20 Insulating substrate 30 Insulating film 40 Internal coil pattern 45 Via electrode 50 Magnetic body 55 Core part 80 External electrode

Claims (18)

A magnetic body including an internal coil pattern formed on at least one surface of the insulating substrate;
An external electrode formed on at least one end surface of the magnetic body and connected to an end of the internal coil pattern;
The magnetic body is a chip electronic component including an unsaturated carboxylic acid polymer. The chip electronic component according to claim 1, wherein the magnetic body further includes a siloxane copolymer. The chip electronic component according to claim 1, wherein the magnetic body includes a metallic soft magnetic material. The chip electronic component according to claim 3, wherein a particle diameter of the metal-based soft magnetic material is 0.1 μm to 30 μm. The chip electronic component according to claim 1, wherein the unsaturated carboxylic acid polymer has a weight average molecular weight of 500 to 2,300. The chip electronic component according to claim 2, wherein the siloxane copolymer has a weight average molecular weight of 500 to 2,300. 2. The chip electron according to claim 1, wherein the unsaturated carboxylic acid polymer is included in an amount of 0.5 to 2 parts by weight with respect to 100 parts by weight of the metallic soft magnetic material included in the magnetic body. parts. 3. The chip electronic according to claim 2, wherein the siloxane-based copolymer is included in an amount of 0.05 part by weight to 0.2 part by weight with respect to 100 parts by weight of the metallic soft magnetic material included in the magnetic body. parts. The chip electronic component according to claim 1, wherein a filling factor of the magnetic body is 80% or more. Forming an internal coil pattern on at least one surface of the insulating substrate;
Forming a magnetic body by laminating magnetic sheets on the upper and lower portions of the insulating substrate on which the internal coil pattern is formed;
Forming an external electrode on at least one end surface of the magnetic body to be connected to an end of the internal coil pattern,
The magnetic sheet is a method for manufacturing a chip electronic component formed by including an unsaturated carboxylic acid polymer. The method of manufacturing a chip electronic component according to claim 10, wherein the magnetic sheet further includes a siloxane copolymer. The method of manufacturing a chip electronic component according to claim 10, wherein the magnetic sheet includes a metal-based soft magnetic material. The chip electronic component manufacturing method according to claim 12, wherein a particle diameter of the metal-based soft magnetic material is 0.1 μm to 30 μm. The method for manufacturing a chip electronic component according to claim 10, wherein the unsaturated carboxylic acid polymer has a weight average molecular weight of 500 to 2,300. The method for manufacturing a chip electronic component according to claim 11, wherein the siloxane copolymer has a weight average molecular weight of 500 to 2,300. The said magnetic body sheet | seat contains 0.5 weight part-2 weight part of the said unsaturated carboxylic acid type polymer with respect to 100 weight part of metallic soft magnetic materials contained in the said magnetic material sheet. Manufacturing method for chip electronic components. The said magnetic material sheet is 0.05 weight part-0.2 weight part of said siloxane-type copolymers with respect to 100 weight part of metallic soft magnetic materials contained in the said magnetic material sheet. Manufacturing method for chip electronic components. The method of manufacturing a chip electronic component according to claim 10, wherein a filling rate of the magnetic body is 80% or more.

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