JPS63310930A - Copper alloy for flexible print - Google Patents

Abstract

PURPOSE:To improve the flexibility, tensile strength, adhesion, etc., of the titled copper alloy by regulating the compsn. limit value of Cr, Sn, etc. CONSTITUTION:The alloy contg., by weight, 0.0001-0.5% Cr and 0.0001-0.5% Sn, furthermore contg., as auxiliary components, one or more kinds of each 0.0001-0.3% and total 0.0001-0.5% elements among Zn, Mn, Mg, Fe, Ni, Al, Si, Co, Ca, Ti, Zr, V, Ag, Cd, Ga, Ge, In, As, Sb, Bi, Be, P, Y, Nb, B, Te, etc., and consisting of the balance copper with inevitable impurities is prepd. In said inevitable impurities, about <=500ppm O2 content and about <=10ppm S content are preferably regulated. By this method, the copper alloy having excellent tensile strength, flexibility and adhesion, having good electroconductivity and is suitable for a flexible print and IC tape carrier can be obtd.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a copper alloy for flexible printing, and more specifically, a copper alloy for flexible printing and IC tape carriers that has excellent tensile strength, flexibility, and good conductivity. This relates to a suitable copper alloy.

[Prior art and its problems]

A flexible printed wiring board is a relatively new component of printed wiring boards, and its major feature is that it utilizes flexibility. This flexible printed wiring board was first used as a substitute for electric wires and cables where flexibility was required, and is still mainly used as a substitute for electric wires and cables. Flexible printed wiring boards take advantage of their flexibility and can be bent or twisted to be used as three-dimensional wiring materials in devices such as cameras, calculators, and telephones. It is also used for wiring to moving parts of equipment.

Furthermore, in the field of integrated circuits, with the recent trend toward lighter, thinner, and smaller
IC packages are also undergoing various changes, and among them, the TAB method (Tape A) is expected to increase in demand in the future.
There is a need for a material suitable for packaging using auto+wated bonding.

Conventionally, tough pitch copper has been mainly used for these applications, but although it has good electrical conductivity of about 100% lAC3, it has had the problem of insufficient tensile strength and flexibility.

[Problem that the invention seeks to solve]

As a result of studies on the above-mentioned problems, the present invention has developed a copper alloy for flexible printing that has approximately the same electrical conductivity as tough pitch copper, and has significantly better tensile strength and flexibility than tough pitch copper.

(Means and effects for solving the problems) The present invention has the following features:
Cr0.0001-0.5wt%, S n0. ooo1
~Q, including 5 wt%, and further contains Zn, Mn, Mg5Fe
, Ni, Al, St, Co, Ca, Ti, Zr.

■, Ag, Cd, , Ga5Ge, In, As, Sb.

0.0001 to 0.3 wt% of one or more of Bi, Be, P, Y, Nb, B, Te, etc. alone, 0-0001 to 0.3 wt% in total, 0.0001 in total ~
This is a copper alloy for flexible printing, containing 0.5 wt% of Cu, and the remainder being Cu and unavoidable impurities.

That is, in the present invention, trace amounts of Cr and Sn are added to Cu, and Zn, Mn, Mg, Fe, N
i, A, L St, Co, Ca, Ti.

Zr, V, Ag, Cd, , Ga, Ge, In, As
.

By adding one or more of Sb, Bi, Be, , P, Y, Nb, B, , Te, etc., the resistance and flexibility are significantly improved without significantly reducing the electrical conductivity. It is something. In the present invention, the reason why the alloy composition is limited as described above is as follows: Cr is 0.0001~
The reason why Cr is set at 0.5 wt% is that Cr is finely interposed as a single Cr in the copper matrix to improve the flexibility of the alloy.
Although it is an element that improves tensile strength, if it is less than 0.0001 wt%, its effect is small, and if it exceeds 0.5 wt%, it tends to form coarse Cr precipitates (which deteriorates the above properties.Sn The reason why Q,
This is because if it exceeds wt%, the conductivity will be lowered.

In addition, Zn, Mn, Mg, Fe, Ni, A as subcomponents
l, Si, Co5Ca, Ti5Zr, V, Ag, Cd,
Ga, Ge, In5As, Sb, Bi, Be, P, Y,
Nb, BXTe, etc. not only act as deoxidizing and desulfurizing elements, but also have the effect of further improving tensile strength and flexibility, but if it is less than 0.0001-t%, it has no effect.
When the amount exceeds 0.3 wt% individually and 0.5 wt% in total, the conductivity decreases.

In addition, the unavoidable impurities in the present invention refer to impurities contained in ordinary metals or impurities introduced during the manufacturing process, such as As, Sb, Bi, PbS, Fe, Ox, etc. This stipulates the 02nd generation.
The reason why 0□ is set to 5001)l)+1 or less is that if this value is exceeded, coarse Cr oxides are likely to form, reducing tensile strength and flexibility, and adhesion to resin after surface roughening treatment. This is because it makes things worse. The reason why Si is set to top per million is because if this value is exceeded, S tends to concentrate at grain boundaries, impairing hot rolling properties and reducing productivity, and also tends to form coarse compounds with Cr, resulting in poor properties. There is no problem with regard to impurities other than 02 and P, as long as they are normally observed, and those that overlap with the subcomponents of the present invention, such as As, Sb, Bi, and Fe, should be combined within the above composition range. If it is included, it will exert its effect as a subcomponent.

〔Example〕

An embodiment of the present invention will be described below.

After melting and casting the alloy of the present invention shown in Table 1 to obtain an ingot with a width of 480 m, a thickness of 130 m, and a length of 2200 m +,
Hot-rolled at a temperature of ~930°C to a thickness of 12 nm, immediately cooled to around room temperature with cooling water, then milled the upper and lower surfaces by 0.5 m, and then cold-rolled to a thickness of 0.5 -
It was annealed at 480° C. for 3 hours in a non-oxidizing atmosphere, and then cold rolled to a thickness of 0.035 ma+ to obtain a test material.

As a comparative alloy, an ingot of Tough Pitch copper with a width of 480 mm, a thickness of 130 mm, and a length of 220 mm was hot rolled at a temperature of 860"C, and then the top and bottom surfaces were face-milled by 0.5 m + s.
cold rolled to 420°C in a non-oxidizing atmosphere.
The sample material was annealed for 3 hours and cold rolled to a thickness of 0.0035 mm.

The above-mentioned test materials were annealed at 500°C for the present alloy and 270°C for the comparative material, and the flexibility, tensile strength,
Properties such as elongation, electrical conductivity, and adhesion were measured. As for flexibility, a bending strength test was conducted using a 15 m long specimen material under a load of 500 gf according to the JIS P8115 method.
The radius of curvature r = 0.381 m, n = 10, and the average value was adopted. The tensile strength and electrical conductivity were determined by a tensile test and measurement of electrical resistance using a strip sample with a width of 10 mm. Regarding adhesion to the resin, the surface of the sample material was roughened by etching and then adhered to the phenol base material, and the peel strength was determined. These results are shown in Table 2-1 and Table 2-2. In Table 2-2, the test pieces were taken in the direction parallel to the rolling direction, and in Table 2-2, the test pieces were taken in the direction perpendicular to the rolling direction.

Table 2-2 As is clear from Tables 1 and 2, the alloy of the present invention 1
-5 is 0 compared to conventional tough pinch copper bars 6 and 7. Although the conductivity is slightly lower, the tensile strength and flexibility are much better, and the peel strength is also significantly higher (suitable for flexible printing. On the other hand, the comparison material NQ8 has a large amount of 0□, so its properties are degraded.Although the direction in which the sample was collected is slightly lower in the direction perpendicular to the rolling direction than in the parallel direction, the above properties are still lower. The trends are exactly the same.6 [Effects] As explained above, the present invention has excellent flexibility, conductivity, tensile strength, adhesion, etc., and can be used as a base material for flexible printing and for IC tape carriers. It is suitable for applications where flexibility is required, such as as a paper towel, and is also effective for rigid printing, and exhibits remarkable industrial effects.

Claims (2)

[Claims] (1) Cr0.0001-0.5wt%, Sn0.00
01 to 0.5 wt%, further Zn, Mn, Mg, Fe,
Ni, Al, Si, Co, Ca, Ti, Zr, V, Ag
, Cd, Ga, Ge, In, As, Sb, Bi, Be,
0.0001 to 0.3 wt% of one or more of P, Y, Nb, B, Te, etc. alone, 0.0001 in total
A copper alloy for flexible printing containing up to 0.5 wt% and the remainder consisting of Cu and unavoidable impurities. (2) The amount of O_2 in the inevitable impurities is 500 ppm or less, S
The copper alloy for flexible printing according to claim 1, characterized in that the amount is 10 ppm or less.