JPH01238930A - Metal plate base copper-laminated plate - Google Patents

Abstract

PURPOSE:To improve solder heat resistance, thermal pressure resistance, bending workability and adhesive properties of an insulating layer by composing the insulating layer of a first insulating layer formed of heat resistant resin at the side of a copper foil, and a second insulating layer formed of thermosetting resin at the side of a metal plate. CONSTITUTION:In a laminated plate in which a copper foil 1 is adhered through an insulating layer to a metal plate 4, the insulating layer is composed of a first insulating layer 2 at the side of the foil 1, and a second insulating layer at the side of the plate 4. The layer 2 is formed of heat resistant resin having 200 deg.C or higher of glass transition point and a normal chain structure such as polyimide, polyamideimide, etc., its thickness is preferably 10mum to 40mum, thereby obtaining heat pressure resistant effect. The second layer 3 is formed of thermosetting resin modified with maleimide resin. As the maleimide, epoxy resin, phenol resin, etc., are employed, and they are modified to provide excellent performance in the adhesive properties, solder heat resistance with the layer 2 without loss of bending workability.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is used as a printed wiring board for electronic A devices, and is particularly excellent in heat resistance and adhesion, and can be bent and drawn at room temperature, making it a structural material. The present invention relates to metal plate-based copper-clad laminates that also have the following properties.

(Prior art) In recent years, with the miniaturization and higher density of electronic components, printed wiring board materials for mounting these electronic components have been increasing in heat dissipation,
Copper-clad laminates based on metal plates are attracting attention due to their excellent dimensional stability and electromagnetic shielding properties, and their usage is also on the rise.

Furthermore, recently, metal sheet copper clad steel sheet can be bent and drawn for the purpose of integrating into a case or storing parts by taking advantage of the strength and plastic workability of metal sheets, and it can also be used as a structural material. There is a demand for a board that can do this.

The insulating layer that adheres between the steel foil and metal plate of conventional metal-based copper-clad laminates is one made of thermosetting resin, one made of thermosetting resin with a 2-layer base, and one made of glass. Those using prepreg impregnated with resin and 5X fiber cloth are not used. These insulating layers are very hard and have excellent heat resistance, but what happens when you bend them? There was a problem that cracks appeared in the 2-layer, causing cracks in the copper foil, peeling between the metal plate and the insulating layer, etc., and a decrease in electrical insulation performance.

There is also a method of using a flexible adhesive such as polyolefin or rubber-modified thermosetting resin as the insulating layer. Although this method has excellent bending workability, it has poor heat resistance, so in printed wiring board processing, the insulating layer may bleed during the solder reflow process used when mounting components, and the soldering layer may swell during manual soldering work. Another problem was that the lead wires of the mounted components could break through the insulation layer, causing insulation defects.

(Problems to be Solved by the Invention) As a method for improving the bending workability and heat resistance, Japanese Patent Publication No. 59-36992 and Japanese Patent Publication No. 5595-1987 disclose a heat-resistant layer on the copper foil side. A first insulating layer made of a resin having creep properties and a second insulating layer made of a flexible resin on the metal plate side.
We are proposing an insulating layer with a two-layer structure with different edges. This method is superior in heat and pressure resistance characteristics of soldering irons, etc., and because of the different insulation properties, it is difficult to determine whether the first and second insulating layers are exposed. If you do this, the first
, there were problems with reliability as the second insulating layer (foil was peeled off) and peeled off when the foil was peeled off. Because it is a resin, it has a small radius of curvature [...] There was a problem that cracks would occur in the steel foil when it was processed.Furthermore, flexible resins have low heat resistance, so... Solder 3↑ heat build-up was also a problem.

In view of these points, the present invention provides a highly reliable copper-clad laminate based on a gold-plated plate that has excellent soldering heat resistance, heat-pressure resistance characteristics, and bending workability, as well as excellent insulation layer density. It is an object of the present invention to provide an embroidery method that can also be used with ordinary steel foil.

That is, as shown in FIG. 1, the present invention has a first structure in which the insulating layer is formed on the copper foil side of a heat-resistant resin having a glass transition point of 200° C. or higher and a linear structure. The present invention relates to a metal plate-based copper-clad laminate characterized in that it has an edge layer 2 and a second insulation layer 6 made of a thermosetting resin modified with a maleimide resin on the metal plate side. The present invention will be explained in detail below.

First in the present invention? The @ layer is a heat-resistant resin having a glass transition point of 200° C. or higher and a linear structure. The reason why the glass transition point (Tg) is set at 200°C or higher is to ensure heat and pressure resistance.If Tg is less than 200°C, an insulating layer must be applied to the lead wire of the soldering iron case or chip components during soldering work. It may break through and cause insulation failure. Also, the reason why we limited it to linear structures is that they have superior bending workability, and this first ? Examples of the resins used in the , #layers include bolyi ξ-do, boria ξ-timide, polyester thread, bismaleimide thread, polysulfone resin, aromatic polyamide resin, and the like. The thickness of this first insulation layer is 10
Preferably, the thickness is not less than μm and not more than 40 am, and less than 10 μm,
The effect of heat and pressure resistance characteristics cannot be obtained, and if the thickness exceeds 40μ, it becomes difficult to perform bending work with a small radius of curvature.

As the first insulating layer, a thermosetting resin such as polyamide that has an epoxy group or an acetylene group at the end forms a network structure, so cracks occur during bending with a small radius of curvature of 6R or less. Insulation failure may occur due to breakage of the steel foil. This is considered to be due to the mesh structure, which reduces the degree of freedom of the q * moon and makes it rigid.

The second P edge layer in the present invention is a thermosetting resin modified with a maleimide resin. Thermosetting resins include epoxy resins, phenol resins, melamine resins, acrylic resins, polyester resins, etc., and curing may be performed using a curing agent applied to these resins. Furthermore, bending workability can be improved by reacting or adding rubber threads such as NBR-CTBN, acrylic rubber, polyurethane, and polyvinyl butyral to the stiff thermosetting resin. The saturated amount of this rubber-based resin is preferably 51 parts by weight or more and less than 60 parts by weight; if it is less than 5 parts by weight, no improvement in bending workability will be observed, and if it exceeds 30 parts by weight, the density with the 11th Q edge layer will increase. Deterioration of layer properties and heat resistance occur.

By modifying this thermosetting resin with manimide resin, it is possible to form a bond between the first insulating layer and the first insulating layer without impairing bending workability.
It can also have excellent layer properties and soldering heat resistance. In other words, by modifying with a maleium oxide resin, heat resistance is improved, and the first ? Since it has a functional group similar to that of the edge layer, it can improve adhesion.

It is preferable that the maleibad-based resin is modified with 5 parts or more and 1:1 or less of the thermosetting resin, and if it is less than 5 parts by weight, heat resistance and adhesion effects cannot be obtained. figure,
40m! , beyond the i portion, flexibility decreases and bending workability with a small radius of curvature is impaired. As the maleimide resin, those commercially available from Mitsubishi Yuka etc. can be used.

Steel P used in the present invention! For +, electrolytic steel W3 or rolled @ foil is used. Further, the metal plate used in the present invention is
These include iron plates, aluminum plates, copper plates, brass plates, etc., and gold M plates depending on the purpose may also be used. These metal plates are preferably subjected to anti-rust treatment such as galvanizing, silane coupling agent treatment, surface roughening, chemical conversion coating, etc. to improve adhesion.

The present invention will be explained in more detail below based on Examples. In addition, although the example showed an example of a single-sided copper-clad laminate, steel foil may be adhered to both sides of the metal plate.

Example 1 A polyetheramide thermoplastic aromatic polyamide thread (trade name: Heimaru 1210, manufactured by Nikbun Seiko Tokyo) was coated on a 35 μm thick electrolytic copper plate and dried to form a 25 μm thick first insulating layer. . The Tg of this resin was 230°C. f
Maleibide resin (part name MP-2000
X: 10 parts by weight of Mitsubishi Yuka ■) and polyamide resin as a hardening agent were mixed and applied onto the first insulating layer and dried,
A second absolute layer having a thickness of 25 ttm was formed. The metal plate is Q,
Using a galvanized steel sheet with a thickness of 5.5, the coated steel foil was layered on top of the steel sheet and heated and pressed in a bundt to obtain a galvanized steel sheet-based copper-clad laminate.

Implementation fQ2 2.2 Bis(4(4aξ)2enoquine)2-dyl)propane was dissolved in N-methylpyrrolidone, and benzophenonetetracarboxylic anhydride was added and mixed to prepare an imide resin.

Apply the above imide resin to 65 μm thick electrolytic copper, dry,
A cyclization reaction was carried out to form a 20 μm thick chain-shaped polyimide resin first rim)*.

The Tg of this resin was 245°C.

In addition, CTBN modified E-modified Nobokin resin BN Ichika ■: 10
Weight @ 11) and maleimide resin (product name MP-200)
0X (manufactured by Sanai Yuka ■) was mixed in 30 overlapping parts, and this mixture was applied to the ± of the first Kasugan layer and dried to form a second insulating layer with a thickness of 25 μm.

A galvanized copper plate with a thickness of Q-5tnra was used as the metal plate, and the above-mentioned coated steel foil was rolled onto this steel plate and heated and pressed in a press to obtain a galvanized steel plate-based copper-clad laminate.

Example 3 358m electrolytic G14 foil made of thermoplastic aromatic polyamide-based polyetheramide (trade name Hymar 1210:
(manufactured by Nizu Kasei Kogyo Haru) was applied and dried to form a first layer with a thickness of 25 Ltm. The Tg of this resin was 230°C. Thereafter, in the same manner as in Example 1, a galvanized steel sheet paste copper VT laminate was obtained.

Example 4 A first loquat layer was formed in the same manner as in Example 1, and a second insulating layer was made of 15 parts by weight of epoxy resin (trade name Epicoat 1001: Yuka Shell Epoxy ■1) KNBR and the lumide resin. Diazenodiphenylsulfone as a curing agent and dazole as a curing agent were mixed together in an amount of 1Ol, and the first insulating node was mixed.
A second insulating layer having a thickness of 30 μm was formed by coating and drying. After polishing and silane coupling treatment of a 0.6 city thick aluminum plate, the above-mentioned coated steel 2 and the like were stacked, heated and pressurized to obtain an Aldium plate-based wAgi laminate.

Comparative Example 1 An aluminum plate-based copper flax laminate was obtained in the same manner as in Example 3 except that the maleimide resin was not used in the second ladle layer in Example 4.

Comparative example 2 35μma! Apply resin of ether ketone thread (part name U polymer: manufactured by Unitika) to electrolytic steel foil and dry it to a thickness of 30 μm.
A thick first insulating layer was formed.

The Tg of this resin was 190°C.

Thereafter, in the same manner as in Example 1, a galvanized steel sheet-paced copper-clad laminate was obtained.

Comparative Example 3 The maleimide resin (MP-2000X) 501 lid part was mixed with 31 parts of epoxy resin (trade name: Epicoat 828 dioilide shell epoxy ■) 501i and imidazole as a hardening agent, and the mixture was coated with 35 am thick electrolytic steel foil. The coating was applied, dried, and cured to form a first insulating layer having a network structure and a thickness of 25 μm. The Tg of this resin was 265°C.

Will the following be implemented? A galvanized steel sheet-based copper-clad laminate was obtained in the same manner as in 1J1.

Comparative Example 4 The polyether amide of Example 1 was applied to a foil of 35 μs and dried, and a 55 am thick film was coated onto the foil. Two marginal layers were formed.

This coating@foil was applied to a galvanized steel sheet and heated and pressed using a press to obtain a galvanized steel sheet paste copper-clad horizontal laminate.

Comparative Example 5 The second insulating layer used in Example 3 and the epoxy resin modified with IWJ maleimide resin were applied to a 65 μm thick foil.
After drying, an insulation layer having a thickness of 40 μm was obtained. An aluminum plate-based copper-clad laminate was obtained in the same manner as in Example 3.

After curing? The Tg of the edge layer is 150℃, and the quality of the gold Jli board-based copper-clad laminate obtained by the method above t0 is shown in Table 1.
are summarized in

Evaluation method: Bending workability: Bending at 90° using a mandrel with two bends of 1.5R and 3R.

○～No abnormality, x～～Foil crack, insulation layer Peel strength: Compliant with JIS C6481.

Solder heat resistance: Same as above. Immerse it in a 300℃ solder bath for 1 minute and observe any abnormalities such as swelling or peeling.

Heat and pressure resistance characteristics: Withstand voltage was measured after pressing a soldering iron (iron shape 1φ) maintained at 400°C against the surface of a copper foil with a load of 3 kg for 1 minute.

Adhesion: After removing the copper foil stuck in the etching, check whether there is any abnormality in the S line layer by PCI', and whether it is due to the cutter? Observe the degree of peeling of the line layer.

○~The insulator is abnormal, and the cutter ・I can't do it.

Δ～～No abnormality in the marginal layer, cutter There is.

× ~ Margin below the occurrence of swelling n of insulation skin and peeling n (effect of the invention) As explained above, if the pressure of the present invention is n, the radius of curvature is 1.5R.
In addition to being able to perform very small bending and drawing processes,
It has excellent soldering heat resistance, heat and pressure resistance for soldering irons, etc., and adhesion of insulating layers. The bent parts also had the same properties as flat parts and bolts, making it possible to obtain extremely reliable metal plate-based copper-clad laminated plates.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a metal plate space horizontal 1=plate according to the present invention. 1...Copper foil 2...11th! ! Edge N 3...2nd
Insulating layer 4...metal plate

Claims (1)

[Scope of Claims] 1. In a metal plate-based copper clad laminate in which a copper foil is bonded to a metal plate through an insulating layer, the insulating layer has a glass transition point of 200° C. or higher on the copper foil side and is direct. It is characterized by comprising a first insulating layer formed of a heat-resistant resin having a chain-like molecular structure, and a second insulating layer formed of a thermosetting resin modified with a maleimide resin on the metal plate side. Metal plate based copper clad laminate. 2. The first insulating layer is a resin selected from the group of polyimide, polyamideimide, polyetherimide, bismaleimide, polysulfone, or aromatic polyamide, and the second insulating layer is an epoxy resin, a phenolic resin, a melamine resin,
The metal plate-based copper-clad laminate according to claim 1, wherein the thermosetting resin selected from the group of acrylic resins or unsaturated polyester resins is modified with a maleimide resin.