JPS63226901A - Printed resistor and manufacture of the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Nine Summers The present invention relates to a printed resistor obtained by screen printing from a copper-clad insulating substrate, etc., and to improvements in the manufacturing method thereof.

For example, the printed resistor used in the printed circuit is
~2 As shown in Figure 2, an undercoat layer 3 is provided between both grooves of an insulating substrate 1 on which Cu or Ag conductors 2 are formed on both sides, and a) a part of this undercoat layer 3 and Cu or A
g. An electrode layer 4 is provided on both a part of the conductor 2, and a resistor [15 is provided on both a part of this electrode layer 4 and the remainder of the undercoat layer 3 (in the case of FIG. 1). ), or b) the resistor layer 5 is provided in the center of the undercoat layer 3, and a portion of the resistor layer 5, the remainder of the undercoat layer 3, and a portion of the Cu or Ag conductor are further provided. A device in which an electrode layer 4 is provided on top of the electrode layer (the case shown in FIG. 2) is known. Note that the undercoat layer 3 is an optional layer provided to strengthen the adhesive force between the substrate, the electrode layer, and the resistor layer. Here, the resistor layer 5 is usually made of a thermosetting resin binder,
In particular, it is mainly composed of epoxy resin and conductive powder such as nickel powder and carbon powder, the undercoat layer 3 is composed of a similar thermosetting resin binder and inorganic fillers such as silica and alumina, and the electrode layer 4 is composed of epoxy resin. .

Thermosetting resins or thermoplastic resin binders such as urethane, tan resins, alkyd-melamine resins (mixtures of alkyd resins and butylated melamine-formaldehyde resins), especially epoxy resins or alkyd-melamine resins, and high Mainly composed of conductive powder.

As described above, epoxy resin binders are widely used in conventional printed resistors, especially in the resistor layer. However, although epoxy resin is suitable for screen printing, it has a drawback of poor heat resistance and a large rate of change in the resistance value of the resistor at high temperatures of about 150°C.

Therefore, in order to improve the heat resistance of the resistor layer.

Attempts have been made to use polyimide resin instead of epoxy resin, but polyimide resin has poor adhesion and is prone to cracking due to its brittleness. It was difficult to obtain heat-resistant printed resistors. A modified polyimide binder in which a polyimide resin is slightly modified with an epoxy resin, urethane resin, etc. is used, but since this uses a resin with very low heat resistance, its heat resistance is inferior to that of a single polyimide binder.

The object of the present invention is to maintain the inherent heat resistance of the polyimide resin even though polyimide resin alone is used as the binder of the resistor layer, so that the rate of change in resistance value at high temperatures is small.
Moreover, it is an object of the present invention to provide a printed resistor that provides good adhesion and does not cause cracks, and a method for manufacturing the same.

As shown in FIGS. 1 and 2, one part of the printed resistor of the present invention is as follows.
An undercoat layer mainly composed of a thermosetting resin binder and an inorganic filler is provided between both grooves of an insulating substrate with Cu or Ag conductors formed on both sides, and a) a part of this undercoat layer and Cu or An electrode layer mainly composed of a resin binder and a highly conductive powder is provided on both of the two parts of the Ag conductor, and a thermosetting resin binder and A resistor layer containing conductive powder as a main component is provided, or b) the resistor layer is provided in the center of the undercoat layer, and a part of this resistor layer, the remainder of the undercoat layer, and Cu or In the printed resistor in which the electrode layer is provided on a part of the Ag conductor, the binder of the undercoat layer is made of a mixed system of polyimide resin and polyamide-imide resin, and the binder of the resistor layer is made of polyimide resin. It is characterized in that the binder of the electrode layer is made of a heat-resistant resin only in the case of a).

The method for manufacturing the printed resistor of the present invention as shown in Figures 1 and 2 involves etching a copper-clad insulating substrate, plating Cu or Ag on the insulating substrate, or coating a highly conductive paint containing Cu or Ag. By doing this, an absolute paint containing a thermosetting resin binder and an inorganic filler as main components is applied between both grooves of an insulating substrate on which Cu or Ag conductors are formed on both sides.

Curing or drying by heating to form an undercoat layer, a) a part of this undercoat layer and Cu or Ag
A conductive paint containing a resin binder and a highly conductive powder as main components is applied on both parts of the conductor, and is cured or dried by heating to form an electrode layer, and then a part of this electrode layer and an undercoat layer are applied. b) A resistive coating mainly composed of a thermosetting resin binder and a conductive powder is applied on both of the remaining parts, and the resistive coating is heated and cured to form a resistor layer, or A printed resistor in which a resistor layer is provided as described above, and an electrode layer is formed on a portion of the resistor layer, the remainder of the undercoat layer, and a portion of the Cu or Ag conductor as described above. In the manufacturing method, a mixed system of a polyimide resin precursor and a polyamideimide resin precursor is used as the binder of the undercoat layer, a polyimide resin precursor is used as the binder of the resistor layer, and a is used as the binder of the electrode layer. ) is characterized in that a heat-resistant resin is used only in the case of

Another type of printed resistor of the present invention, as shown in FIG. An undercoat layer containing a thermosetting resin binder and an inorganic filler as main components is provided at the center of the other side of the insulating substrate, and through holes are formed from both sides of this undercoat layer to the surface of the conductor. An electrode layer mainly composed of a resin binder and a highly conductive powder is provided through the substrate, and a thermosetting resin binder and a conductive powder mainly are provided on both a part of the electrode layer and the remainder of the undercoat layer on the opposite side of the substrate. In a printed resistor provided with a resistor layer as a component, the binder of the undercoat layer is made of a mixed system of polyimide resin and polyamideimide resin, the binder of the resistor layer is made of a polyimide resin, and the binder of the electrode layer is made of a mixed system of polyimide resin and polyamideimide resin. It is characterized by being made of heat-resistant resin.

The method for manufacturing the printed resistor of the present invention as shown in FIG. After forming the through holes, an insulating paint containing a thermosetting resin binder and an inorganic filler as main components is applied to the center of the other surface of the insulating substrate, and is cured or dried by heating to form an undercoat layer. A conductive paint containing a resin binder and a highly conductive powder as main components is applied through a through hole from both sides of the undercoat layer to the surface of the conductor, and then heated or cured. An electrode layer is formed by heating and drying, and then a resistive paint mainly composed of a thermosetting resin binder and conductive powder is applied on both a part of the electrode layer and the remainder of the undercoat layer on the opposite side of the substrate. In the method for producing a printed resistor in which the undercoat layer is cured by heating to form a resistor layer, a mixed system of a polyimide resin precursor and a polyamide-imide resin precursor is used as the binder for the undercoat layer, and polyimide is used as the binder for the resistor layer. This method is characterized by using a resin precursor and using a heat-resistant resin as a binder for the electrode layer. Note that the precursor referred to in the present invention means an uncured product. Further, the Cu or Ag conductor can also function as an electrode layer.

The present inventor conducted various studies on the undercoat layer and the electrode layer in order to obtain an unmodified polyimide resin resistor layer with good adhesion and no cracks. the result,
By using a mixed system of polyimide resin and polyamideimide resin as the binder for the undercoat layer, and using a heat-resistant resin as the binder for the electrode layer only in the case of the printed resistors shown in Figures 1 and 3, the desired results can be achieved. I found out that the purpose can be achieved.

The present invention is based on such knowledge.

In the printed resistor of the present invention, the undercoat layer is mainly composed of a binder made of a blend of polyimide resin and polyamideimide resin, and an inorganic filler.

In general, polyimide resins or polyamide-imide resins are of the condensation type by dehydration and ring closure of a polyimide resin precursor such as polyamic acid, and the addition polymerization type by addition of oligomers. Among these, paints (pastes) A polycondensation type is preferable because it has excellent properties when used as a polymer.

In any case, the mixing ratio of polyimide resin and polyamideimide resin in the blend is usually 2:8 to 8:
2. (by weight), preferably in the range of 3:3 to 7:3 (by weight). If the polyimide resin is too small compared to the polyamideimide resin.

When forming the resistor layer, cracks tend to occur at the interface between the undercoat layer and the resistor layer when the resistor paint is heated and cured at, for example, about 250°C, and conversely, if the polyimide resin is too adulterated than the polyamide-imide resin. , the adhesion between the resistor layer and the undercoat layer tends to deteriorate.

Examples of inorganic fillers used in the undercoat layer include silica, alumina, glass, aluminum hydroxide, titanium dioxide, and barium sulfate. The particle size of the inorganic filler is preferably as fine as possible, preferably 100 μm or less, particularly 20 μm or less. The amount of inorganic filler used in the undercoat layer is usually 5 to 1000 parts by weight per 100 parts by weight of the polyimide resin-polyamideimide resin blend.
Parts by weight range. Note that the thickness of the undercoat layer is usually in the range of 1 to 100 μm.

The undercoat layer made of the above materials is the first to second layer.
In the case of the printed resistor shown in the figure, Cu or Ag conductors are formed on both sides between the two conductors of the insulating substrate, and in the case of the printed resistor shown in Fig. 3, Cu or Ag conductors are formed on one side, and A blend of polyimide resin precursor and polyimide amide resin precursor (mixing ratio is As described above) and an inorganic filler as the main components, the insulation coating is applied, heated and dried, and the precursor is subsequently hardened by ring closure. In this case, the heating temperature is usually in the range of 50 to 450°C (however, 50 to 150°C is the drying temperature, and 150°C or higher is the curing temperature). As a solvent, N,N'-dimethylacetamide, bis(2-methoxyethyl)ether, N,N'-dimethylformamide, N-methyl-2-
Examples include pyrrolidone, dimethyl sulfoxide, tetrahydrofuran, 1,3-dioxane, and 1,4-dioxane. As a polyimide resin precursor, the following general formula■
Examples of the polyamide-imide resin precursor include polymers or copolymers consisting of polymer units represented by the following general formula (2).

[However, A is (R, bar o-■-SO, -◎-o-, -0+.

υ Represents 10-0-C (CF, )-0-0-. ).

(R3 is -o+, -C island-, -S ha.

).

(represents x+y=3)].

−〕〇−〇−〇−, represents −0, - OH).

(R, is -o+, -5O□-, -CH,-.

-c-, -co, -, E(co3)z.

Cabinet 〇 -5-).

Preferably Sweet B represents one type of functional group group selected from the group consisting of C.I.

10−〇−〇−◎−0−.

CH3 10-〇-■-〇-, -SO,-.

-P-,-+CF2)3-.

-C(CF,)2-, -+CF,)! −.

-o-(CF2)*-represents -o-).

-0-CH2-◎-CH2-0+.

−〇−〇−〇−〇−〇−2 10−◎−8O□−◎−, −o−◎◎−0−ツ0 @
-@-Ot O@ (represents "2-◎-〇-") Preferably represents one type selected from the following functional group group.

General formula ■: ) R, RK, K K ν [where R is a hydrogen atom, a halogen atom, an alkyl group (e.g. methyl group, ethyl group), X is an oxygen atom, a sulfur atom, a sulfonyl group, a carbonyl group, a carboxyl group, methylene group or dimethylmethylene group, which may be the same or different from each other. ] represents a divalent residue represented by the formula, A r ' represents a divalent residue represented by the formula (however, R and X have the same meanings as above) (hereinafter in the margin) (2) Preferably (Ar is H2).

It should be noted that the polyimide resin precursor of the general formula (1) has at least 1
aromatic, heterocyclic, cycloaliphatic or aliphatic, preferably anhydrides of aromatic or heterocyclic tetracarboxylic acids and at least one aromatic.

It is obtained by reaction with a cycloaliphatic or aliphatic, preferably aromatic, diamine. In addition, the polyamide-imide resin precursor of the general formula H can be produced by a reaction between an aromatic diamine and trimellitic anhydride (amine reaction), a reaction between an aromatic diisocyanate and trimellitic anhydride (isocyanate method), and a reaction between an aromatic diamine and trimellitic anhydride (isocyanate method). Obtained by reaction with trimellitic acid chloride (acid chloride method), etc.

Each of the above precursors is easily available as a commercial product. For example, commercially available polyimide resin precursors include Ube Industries (
Stock) 11! Examples include U varnish, Bayer ML manufactured by DuPont, and IIL A RC-TPI manufactured by Mitsui Toatsu Chemical Co., Ltd. Commercially available polyamide-imide resin precursors include TI Polymer manufactured by Hitachi Chemical Co., Ltd. (>mHl-400, Toshishiku Co., Ltd.).

Note that the Cu or Ag conductor on the insulating substrate is a copper-clad insulating substrate (
(generally called a copper-clad laminate), plated Cu or Ag on an insulating substrate, or
It is formed by applying a highly conductive paint containing u or Ag. Here, the insulating substrate is usually a metal base substrate (based on a metal plate such as AQ, coated with a relatively heat-resistant insulating resin such as an epoxy resin containing an inorganic filler), an enamel substrate, etc. .

Heat-resistant substrates such as ceramic substrates, polyimide substrates, and glass substrates are used, but if special manufacturing methods such as manufacturing printed resistors in an atmosphere of saturated vapor of an inert liquid are used, epoxy resin-impregnated glass substrates can be used. , phenolic resin-impregnated paper substrates, etc. can also be used.

Next, the electrode layer of the present invention is mainly composed of a resin binder and a highly conductive powder, and has a resistance value of 1 when the film thickness is 10μ.
It is less than ΩΩ. As a binder, when forming an electrode layer before forming a resistor layer (in the case of Figures 1 and 3), the heating temperature (N, time, maximum Heat-resistant resin 1 such as polyimide resin, polyimide amide resin, bismaleimide triazine resin (BT resin), cresol novolac type epoxy resin, polyether sulfone resin, polysulfone resin, polyether
Etherketone resin, fluororesin, etc. are used. However, in the case where the electrode layer is formed after the resistor layer is formed (as in the case of FIG. 2), heat resistance as described above is not required, and therefore, the above-mentioned heat-resistant resin can of course be used as the binder.

Resins with low heat resistance such as bisphenol A type epoxy resins, urethane resins (common resins with OH group end molecular weights obtained by the reaction of polyols and diisocyanates), and alkyd/melamine resins can also be used.

The volume resistivity of the highly conductive powder used for the electrode layer is 10.
-3~to-'Ω1 metal powder, e.g. Au, P
Preferably noble metal powders such as T, Ag, Pd, Ni, Cr, No, etc., especially Ag powders are mentioned, but C
Metal powders that are relatively easily oxidized, such as U and Ag, can also be used if surface treatment is performed to prevent oxidation.

Further, mixtures and alloys of the above metal powders (including those treated with anti-oxidation treatment) can also be used. The particle size of the highly conductive powder is preferably as fine as possible, preferably 100 μm or less, particularly 20 μm or less. The amount of highly conductive powder used in the electrode layer is usually 100 to 10,000 parts by weight per 100 parts by weight of the resin binder. Parts by weight range. Further, the thickness of the electrode layer is usually in the range of 1 to 100 μm.

When making the printed resistor shown in Figure 1, the electrode layer made of the above materials is screen printed on both a part of the undercoat layer formed as described above and a part of the Cu or Ag conductor. A conductive material whose main components are a resin binder or its precursor and a highly conductive powder is prepared by the method. When a paint is applied and heat-cured or heat-dried, or when a printed resistor as shown in FIG. It is formed by similarly applying a conductive paint on the remaining portion (both sides) of the undercoat layer and a portion of the Cu or Ag conductor, and heating and drying, curing or simply heating and drying. The printed resistor shown in FIG. 3 is almost the same as the one shown in FIG. 1, except that the conductive paint is applied through the through holes.

In this case, the heating temperature varies depending on the type of binder, and is generally 100 to 300°C when heat-resistant resin is used.
, and when other low heat resistant resins are used, it is usually 50 to 200.
℃ range. The solvent also differs depending on the type of binder, and is appropriately selected from, for example, the above-mentioned solvents for insulating paints, ketones (acetone, methyl ethyl ketone, etc.), and the like.

Next, the resistor layer of the present invention is mainly composed of a polyimide resin binder and conductive powder, and has a resistance value of 10 μm in thickness.
m, it exceeds 1Ω/mouth. A polyimide resin binder is necessary to maintain a stable resistance value at high temperatures of 150° C. or higher. As in the case of the undercoat layer, such polyimide resin is preferably of the polycondensation type. As a conductive powder, the volume resistance value to-'~1O1
1 inorganic powder, such as Au, Ag, Pt, P
Metals such as d, Ni, Cr; carbon, graphite; tin oxide,
Examples include powders of metal oxides such as indium oxide, cobalt oxide, and chromium oxide. Also, Cu, AQ, Fe,
Metals that are relatively easily oxidized, such as Mg, Sn, and Pb, can also be used if they are treated to prevent oxidation. Furthermore, alloys of the above metal powders (including those treated to prevent oxidation) can also be used. Furthermore, two or more of the above conductive powders can be used in combination. The particle size of the conductive powder is preferably as fine as possible, preferably 100 μm or less, particularly 20 μm or less. In order to adjust the resistance value, the resistor layer may contain other inorganic fillers such as those used in the undercoat layer. Can be added.

The amount of conductive powder used in the resistor layer varies widely depending on the type and resistance value, and is usually in the range of 2 to 10,000 parts by weight per 100 parts by weight of the polyimide resin. Further, the thickness of the resistor layer is usually in the range of 1 to 100 μm.

When making the printed resistor shown in Figs. 1 and 3, the resistor layer made of the above materials is a part of the electrode layer formed as described above (however, in the case of Fig. 3, it is used as a part of the electrode layer on the other side of the substrate). A resistive paint containing a polyimide resin precursor and a conductive powder as main components is applied by screen printing on both the surface) and the remainder of the undercoat layer, and heated to harden the precursor by ring closure. When making the printed resistor shown in the figure, a resistive paint is similarly applied onto the center of the undercoat layer and cured by heating. The details of the polyimide resin precursor, solvent, heating temperature, etc. used here may be the same as those for the undercoat layer.

The printed resistor obtained as described above may be provided with an overcoat layer containing a suitable insulating resin on at least a portion of the surface for the purpose of surface protection.

The present invention will be explained below by way of examples. Part and %
All are parts by weight.

Example 1 A commercially available copper-clad laminate (an 80 μm thick inorganic filler-rich epoxy resin layer was provided on an Afl base, and a 35 μm thick
A thick copper foil pasted) was cut to 30 m x 25 mm, an etching resist pattern was printed on the copper foil by screen printing, and a Cu circuit was formed through the steps of heat curing, etching, and resist removal1. Next, a varnish consisting of a 20% N-methyl-2-pyrrolidone solution of polyamic acid (presumed structural formula), which is an aromatic polyimide resin precursor, is applied between the Cu conductors of this insulating substrate by a screen printing method (using a 250-mesh mask). (Ube Industries Co., Ltd.)
A varnish (manufactured by Hitachi Chemical Co., Ltd.) consisting of 40 parts of U varnish 5) and a 30% N-methyl-2-pyrrolidone-xylene mixed solvent (mixing ratio 80:20 by weight) solution of an aromatic polyamide-imide resin precursor Hl-400-30 manufactured by Co., Ltd.
, an insulating paint made by mixing 40 parts of the estimated structural formula of the precursor and 20 parts of silica (polyimide precursor: polyamide-imide precursor = 4:6)
A part of this undercoat layer and C
A conductive paint made by mixing 50 parts of the aromatic polyimide resin precursor-containing varnish and 50 parts of silver powder was applied on both parts of the U conductor by a similar screen printing method, and
Ring-closing curing was performed by heating at 0° C. for 10 minutes and at 250° C. for 30 minutes to form a 35 μm thick silver electrode layer. Subsequently, a resistance paint made by mixing 85 parts of the aromatic polyimide resin precursor-containing varnish and 15 parts of carbon powder was applied on both a part of this silver electrode layer and the rest of the undercoat layer by the same screen printing method. It was coated and heated at 150°C for 10 minutes and at 250°C for 60 minutes to cure the ring.
A printed resistor as shown in FIG. 1 was made by forming a resistor layer with a thickness of 0 μm.

On the other hand, for comparison, a bisphenol A type epoxy resin was used instead of the polyimide resin precursor and polyamideimide resin precursor used for each layer, diethylene glycol monobutyl ether was used as the solvent, and the heating temperature was 25.
A printed resistor (Comparative Example 1) was made in the same manner as in this example except that 0°C was changed to 150°C.

Next, one sample of the printed resistor obtained in the above manner was
It was kept in an oven at 50° C. for 1000 hours and the change in resistance value was examined to determine the high temperature storage characteristics.

The results are shown in FIG.

In addition, the printed resistor sample was placed in an oven at 125°C for 10
The resistance was maintained for 00 hours, and the change in resistance value when C power was applied was examined, which was defined as D and C load characteristics. The results are shown in FIG.

Examples 2 to 4 Printed resistors were prepared in the same manner as in Example 1, except that the binder in the varnish used for the undercoat layer, silver electrode layer, and resistor layer was changed as shown in Table 1 below. However, in the case of the alkyd/melamine resin of Comparative Example 4, diethylene glycol monobutyl ether was used as the solvent, and the heating temperature was changed from 250°C to 150°C.

(Left below) Next, these printed resistor samples were examined for adhesion, cracks, and resistance value stability. The results are shown in Table-2.

Table 2 Test method Adhesion: According to J I 5-D-0202, Section 8.12 and cross-cut test. O is 100/100, Δ is 99/100 to 91/
100, X represents 90/100 to O/100.

Cracks: Evaluated by the number of cracks observed on the sample surface using a stereo microscope with 20x magnification. O means O pieces/d, ○ means 1 to 10 pieces/-1
Δ represents 10 to 100 lines/d, and x represents 100 or more lines/d.

Soldering heat resistance: The rate of change in resistance when the sample was subjected to JI 5-C-5202 at a reading temperature of 260°C and an immersion time of 10 seconds. O is within 1%, ○ is 1 to 3%, Δ
represents 3 to 5%, and × represents 5% or more.

High-temperature storage characteristics: Rate of change in resistance after leaving the sample in an oven at 150℃ for 1000 hours, O within 3%, 3-5% after heating
, Δ loses 5 to 10%, and X loses 10% or more.

Comparative Example 7 As an insulating paint for the undercoat layer, 60% of bismaleimide triazine resin (trade name: BT-3109, manufactured by Mitsubishi Gas Chemical Co., Ltd.), which is a type of addition polymerization type polyimide resin, was used.
A printed resistor was produced in the same manner as in Example 1, except that a mixture of 62.5 parts of varnish made of diethylene glycol monobutyl ether solution and 37.5 parts of silica was used.

The performance of this product was inferior to that of Example 1 in high temperature storage characteristics as shown in FIG.

- As mentioned above, the printed resistor of the present invention uses a blend of polyimide resin and polyamide-imide resin as the binder of the undercoat layer, so it provides good adhesion, does not cause cracks, and is heat resistant. Polyimide resin alone, which has a small rate of change in resistance and therefore resistance at high temperatures, can be used as the binder for the resistor layer.

[Brief explanation of drawings]

1 to 3 are block diagrams of general printed resistors, and FIG. 4 is a diagram showing the resistance values of the printed resistors made in Example 1 and Comparative Examples 1 and 7 after being left at high temperatures. FIG. 5 shows the printed resistor glue C made in Example 1. FIG. 3 is a diagram showing changes in resistance value due to load. 1... Insulating substrate 2... Cu or Ag conductor 3... Undercoat layer 4... Electrode layer 5... Resistor layer Patent applicant Tamura Kaken Co., Ltd. Figures 4 to 4

Claims (1)

[Claims] 1. An undercoat layer mainly composed of a thermosetting resin binder and an inorganic filler is provided between both conductors of an insulating substrate having Cu or Ag conductors formed on both sides, and a) this undercoat layer is provided between both conductors. An electrode layer mainly composed of a resin binder and a highly conductive powder is provided on both a part of the layer and a part of the Cu or Ag conductor, and further on both a part of this electrode layer and the remainder of the undercoat layer. or (b) provide the resistor layer in the center of the undercoat layer, and further add a part of this resistor layer to the undercoat layer. The remainder of the coating layer and Cu
Alternatively, in a printed resistor in which the electrode layer is provided on some of the three Ag conductors, the binder of the undercoat layer is made of a mixed system of polyimide resin and polyamide-imide resin, and the binder of the resistor layer is made of a polyimide resin. Consisting of
A printed resistor characterized in that the binder of the electrode layer is made of a heat-resistant resin only in the case of a). 2. Apply an insulating paint containing a thermosetting resin binder and an inorganic filler as main components between both conductors with Cu or Ag conductors formed on both sides, and heat cure or heat dry to form an undercoat layer; a) Apply a conductive paint containing a resin binder and a highly conductive powder as main components on both a part of this undercoat layer and a part of the Cu or Ag conductor, and heat cure or heat dry to form an electrode layer. Then, a resistive coating mainly composed of a thermosetting resin binder and a conductive powder is applied on both a part of this electrode layer and the remaining part of the undercoat layer, and is heated and cured to form a resistive layer. or b) A resistor layer is similarly provided in the center of the undercoat layer, and further on a part of this resistor layer, the remainder of the undercoat layer, and a part of the Cu or Ag conductor. In the method for manufacturing a printed resistor in which an electrode layer is formed as described above, a mixed system of a polyimide resin precursor and a polyamide-imide resin precursor is used as a binder for the undercoat layer, and a polyimide resin precursor is used as a binder for the resistor layer. and as a binder for the electrode layer a)
A method for manufacturing a printed resistor, characterized in that a heat-resistant resin is used only in the case of 3. Cu or Ag conductors are formed on both sides of one surface of the substrate, and a heat-curing layer is applied to the center of the other surface of the insulating substrate, which has a hole penetrating from both conductor surfaces to the other surface of the substrate. An undercoat layer mainly composed of a conductive resin binder and an inorganic filler is provided, and an electrode layer mainly composed of a resin binder and a highly conductive powder is provided through through holes from both sides of this undercoat layer to the surface of the conductor. Furthermore, in a printed resistor in which a resistor layer mainly composed of a thermosetting resin binder and a conductive powder is provided on both a part of the electrode layer on the opposite side of the substrate and the remainder of the undercoat layer, the undercoat layer A printed resistor, wherein the binder is made of a mixed system of polyimide resin and polyamideimide resin, the binder of the resistor layer is made of polyimide resin, and the binder of the electrode layer is made of a heat-resistant resin. 4. Cu or Ag conductors are formed on both sides of one surface of the substrate, and a thermosetting resin is placed in the center of the other surface of the insulating substrate, which has a hole penetrating from both conductor surfaces to the other surface of the substrate. An insulating paint containing a binder and an inorganic filler as its main components is applied and cured or dried by heating to form an undercoat layer, and a resin binder and high-quality resin are passed through through holes from both sides of this undercoat layer to the surface of the conductor. A resin binder containing conductive powder as the main component and a conductive paint containing high conductivity powder as the main component are applied and cured or dried by heat to form an electrode layer, and then a part of the electrode layer on the opposite side of the substrate and Applying a resistance paint mainly composed of a thermosetting resin binder and conductive powder on both of the remaining parts of the undercoat layer,
In a method for manufacturing a printed resistor in which a resistor layer is formed by heating and curing, a mixed system of a polyimide resin precursor and a polyamide-imide resin precursor is used as a binder for an undercoat layer, and a polyimide resin precursor is used as a binder for a resistor layer. 1. A method for manufacturing a printed resistor, characterized in that a heat-resistant resin is used as a binder for an electrode layer.