JPH08940B2 - Copper alloy for flexible printing - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a copper alloy for flexible printing, and more specifically, it has excellent tensile strength and flexibility, and has good conductivity, for full-flexible printing and IC tape carrier. The present invention relates to a conductive alloy suitable for the above.

[Prior art and its problems]

The flexible printed wiring board is a relatively new component in the printed wiring board, and its major feature is to utilize flexibility. This flexible printed wiring board was originally used as a substitute for a wire or cable that requires flexibility, and is still mainly used as a substitute for electric wires and cables. The flexible printed wiring board uses flexibility and bends or twists to be used as a three-dimensional wiring material in devices such as cameras, calculators, and telephones, and because it has excellent flexibility, it is an electronic device of the printer head party. It is also used for the wiring of the moving parts of.

Furthermore, in the field of integrated circuits, various IC packages are changing with the recent trend toward lighter, thinner, shorter, and smaller devices. Among them, the TAB method (Tape Automated
Materials suitable for the Bondig package are desired.

Conventionally, tough pitch copper has been mainly used for these applications, but there is a problem that tensile strength and flexibility are insufficient although the conductivity is good at about 100% IACS.

[Problems to be solved by the invention]

As a result of studying the above problems, the present invention has developed a copper alloy for flexible printing, which has substantially the same conductivity as that of tough pitch copper and has significantly higher tensile strength and flexibility than tough pitch copper.

[Means for solving problems]

The first invention of the present invention is a copper alloy for flexible printing comprising Ti 0.0001 to 0.3 wt% balance Cu and unavoidable impurities, and Ti 0.0001 to 0.3 wt% Zn, Mn, Mg, Fe, N
i, Al, Si, Co, Ca, Tl, Zr, V, Ag, Cd, Ga, Ge, In, As, Sb, Bi, Be,
One of P, Y, Nb, B, Cr and Pb or two or more of them are 0 alone.
0001 to 0.3 wt% 0.0001 to 0.5 wt% in total, balance Cu
A copper alloy for flexible printing, which comprises: and an unavoidable impurity, is a second invention.

That is, the present invention is a significantly improved tensile strength and flexibility without significantly reducing the conductivity by adding a small amount of Ti to Cu, and also by adding a small amount of Ti to Cu, as a subcomponent Zn, Mn, Mg, Fe, Ni, Al, Si, Co, Ca, Tl, Zr, V, Ag, Cd,
Ga, Ge, In, As, Sb, Bi, Be, P, Y, Nb, B, Cr, Pb One or two or more kinds of trace amounts are added to further improve the characteristics. Is.

The reason for limiting the alloy composition of the present invention is as follows.
Ti is set to 0.0001 to 0.3 wt% because Ti is an element that improves flexibility and tensile strength without lowering the conductivity so much.
This is because if it exceeds%, the castability is deteriorated and the hot workability is deteriorated. In addition, the sub-component of Zn or less is a deoxidizing or desulfurizing element, which improves adhesiveness and hot workability with a resin, and has a function of further improving tensile strength and flexibility, but less than 0.0001 wt%. Less effective, 0.3wt alone
%, If the total exceeds 0.5 wt%, the conductivity and productivity will be reduced.

Further, the unavoidable impurities in the present invention refers to impurities contained in ordinary metal or entering the manufacturing process, such as As, Sb, Bi, Pb, S, Fe, O _2, etc. In particular, the amount of O _{2 and the} amount of S are specified, and the reason why O ₂ is 500 ppm or less is that if it exceeds this value, coarse oxides are likely to be formed, the tensile strength and flexibility are lowered, and the surface is roughened. This is because the adhesion with the resin after the treatment is deteriorated. S amount is 10
The reason why the content is set to ppm is that if it exceeds this range, S is likely to be concentrated in the crystal grain boundaries, impair the hot rolling property to lower the productivity, and easily form a coarse compound with Ti, resulting in poor properties. Note that
Impurities other than O ₂ and S may be contained as long as they are normally contained, and those that overlap with the sub-components of the present invention such as As, Sb, Bi, Fe, etc., should be included together in the above composition range. For example, it is effective as an accessory ingredient.

〔Example〕

 An embodiment of the present invention will be described below.

Example 1 The alloy of the present invention shown in Table 1 was melt cast to obtain an ingot having a width of 480 mm, a thickness of 130 mm and a length of 2200 mm, and then hot-rolled at a temperature of 850 to 930 ° C. to a thickness of 12 mm and cooled. Immediately cool to near room temperature with water, then cut the upper and lower surfaces by 0.5 mm and then cold-roll to a thickness of 0.5 mm, and perform 480 in a non-oxidizing atmosphere.
It was annealed at ℃ for 3 hours and cold-rolled to a thickness of 0.035 mm to obtain a test material.

As a comparative alloy, tough pitch copper has a width of 480 mm and a thickness of 130.
mm, length 2200 ingots are hot-rolled at a temperature of 860 ° C, then the upper and lower surfaces are chamfered by 0.5mm, cold-rolled to 0.5mm, and annealed at 420 ° C for 3 hours in a non-oxidizing atmosphere, It was cold-rolled to 0.0035 mm to obtain a test material.

Each of the above test materials was 500 ° C. in the alloy of the present invention, and 2 in the comparative material.
Annealing was performed at 70 ° C. to obtain an annealed material, and the characteristics such as flexibility, tensile strength, elongation, conductivity, and adhesion were measured. For flexibility, a segregation resistance test was conducted by using the method of JIS P8115 and using a test material with a width of 15 mm, a load of 500 gf and a radius of curvature r = 0.38 mm, n = 10.
The average value was adopted. The tensile strength and the electrical conductivity were obtained by measuring the tensile test and the electrical resistance using a strip sample having a width of 10 mm. Regarding the adhesiveness to the resin, the peel strength was determined after the test material surface was roughened by etching and then adhered to the phenol substrate. The results are shown in Table 2 and Table 2. In addition, Table 2 is a specimen parallel to the rolling direction, and Table 2-2 is a specimen taken from a direction perpendicular to the rolling direction.

As is clear from Tables 1 and 2, the alloys of the present invention are
Nos. 1 to 5 have slightly lower electrical conductivity than conventional tough pitch copper Nos. 6 and 7, but are significantly superior in tensile strength and flexibility, and have extremely large peel strength, making them suitable for flexible printing. You can see that On the other hand, comparative material N
The characteristics of o.8 are degraded due to the large amount of O ₂ .

The material sampling direction is slightly lower in the direction perpendicular to the rolling direction than in the direction parallel to the rolling direction, but the characteristics tend to be the same.

Example A test material was prepared using the alloys of the present invention and the comparative alloys having the compositions shown in Table 3 in the same manner as in Example 1, and the characteristics of the test materials were examined in the same manner as in Example 1. The results are shown in Table 4-1 and Table 4-2. In addition, Table 4 shows the values when the sampling direction of the test piece was sampled in parallel with the rolling direction, and Table 4-2 shows the values when the sample was sampled at right angles to the rolling direction.

As apparent from Tables 3 and 4, the alloy N of the present invention
Although o.1 to 5 have slightly lower conductivity than conventional tough pitch copper Nos. 6 and 7, they are remarkably excellent in tensile strength and flexibility, and have extremely large peel strength, making them suitable for flexible printing. You can see that On the other hand, comparative material N
The characteristics of o.8 are degraded due to the large amount of O ₂ . Although the direction of sampling the sample is slightly lower in the direction perpendicular to the rolling direction than in the direction parallel to it, the tendency of the above characteristics is exactly the same.

〔effect〕

As described above, according to the present invention, flexibility, conductivity, tensile strength, adhesiveness, etc. are excellent, and flexibility is required such as suitable for a flexible print and as a base material for an IC tape carrier. Suitable for various uses,
Further, it is also effective for rigid printing and exerts a remarkable industrial effect.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Riki Sato 500 Kiyotakicho, Nikko City, Tochigi Prefecture Furukawa Electric Co., Ltd. Nikko Denki Copper Co., Ltd. Inspector Shuichi Kageyama

Claims (4)

[Claims] 1. A copper alloy for flexible printing, which comprises 0.0001 to 0.3 wt% of Ti, the balance Cu and unavoidable impurities. 2. The inevitable impurities have an O ₂ content of 500 ppm or less and an S content of
Claim 1 characterized in that it is 10ppm or less
The copper alloy for flexible printing according to the item. 3. Ti 0.0001 to 0.3 wt%, and further Zn, Mn, Mg, Fe, N
i, Al, Si, Co, Ca, Tl, Zr, V, Ag, Cd, Ga, Ge, In, As, Sb, Bi, Be,
One of P, Y, Nb, B, Cr and Pb or two or more of them are 0 alone.
0001 to 0.3 wt% 0.0001 to 0.5 wt% in total with the balance being Cu and inevitable impurities. 4. The inevitable impurities have an O ₂ amount of 500 ppm or less and an S amount of
Claim 3 which is less than 10 ppm
The copper alloy for flexible printing according to the item.