JPH04155276A - Withstand voltage testing device of prepreg - Google Patents

Abstract

PURPOSE:To enable a defect part including a conductive substance to be eliminated and withstand voltage failure of a product to be reduced by using a metal or a flexible conductive material for rolls and then changing pressure between the rolls. CONSTITUTION:With upper and lower rolls 5 and 7 as electrodes, uniform line contact through a prepreg 3 between these rolls is made. Since a thin projecting part exists on a surface of the prepreg 3, pressure is applied between the rolls using a metal roll for collapsing the projecting part for uniform contact. Then, a conductive substance which deviates in thickness direction of the prepreg is detected by achieving adhesive contact following a surface of the prepreg using the rolls which utilize the conductive and flexible material 7.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a prepreg used for an insulating layer of an insulating board, a copper-clad laminate, or a printed circuit board.

[Conventional technology]

Although withstand voltage tests have been conducted on insulating boards and copper-clad laminates manufactured using prepreg, no examples have been found of withstand voltage tests at the prepreg stage.

[Problem to be solved by the invention]

After the prepreg is processed into insulating boards, copper-clad laminates, and printed circuit boards, and after being molded, a withstand voltage test is conducted. Tests are conducted to detect defects before the prepreg is used.

[Means to solve the problem]

As a method of testing the withstand voltage by applying a specified voltage to the entire surface of the sorted prepreg, the upper and lower rolls are set as 't:L poles, and the prepreg is passed between these rolls so that they are in uniform contact by line contact (Figure 1 Since there are small protrusions on the surface of the prepreg, we use metal rolls to apply pressure between the rolls to crush the protrusions and make uniform contact. In addition, by using a roll made of a soft and attentive material, it is possible to follow the irregularities on the surface of the prepreg and come into close contact with it, making it possible to detect conductive substances that are misaligned in the thickness direction of the prepreg. shall be.

[Effect]

The two rolls located above and below serve as electrodes for the withstand voltage test, and the prepreg passes through it in line contact with the electrodes, and the entire surface is tested. With the metal rolls, pressure is applied between the rolls to crush the convexities on the surface of the prepreg so that the electrodes can evenly touch the entire surface of the prepreg. With soft conductive rolls, line contact becomes surface contact with a certain width due to the pressure between the rolls, making it possible to detect even when the conductive substance is misaligned on the upper and lower surfaces of the prepreg.

〔Example〕

Diameter φ1001 made of conductive rubber with Shore hardness 40
A DC voltage of 500V was applied to the upper and lower two electrode rolls, and the meter was set on the Kanto electric film, and a width of 1000 mm and a thickness of 0.2 mm was made of glass cloth base material and epoxy resin.
A withstand voltage testing device with a conveyor that can continuously flow 1mm prepreg.

〔Effect of the invention〕

By using a prepreg withstand voltage testing device, it became possible to remove defective parts containing conductive substances, reducing withstand voltage defects in products processed in post-processes using the selected prepreg.

[Brief explanation of the drawing]

FIG. 1 is a side view of an apparatus showing an embodiment of the present invention, FIG. 2(a) is a side view of an example in which a metal roll is used as the roll, and FIG. Figure (b) shows another embodiment of the present invention, in which pressure is applied between two rolls made of a soft conductive material, and the rolls deform and come into partial surface contact.
FIG. 6 is a side view showing a detection state when conductive substances are disposed vertically and shifted. 1 Upper electrode roll 2 Lower electrode roll 3 Prepreg 4 Feed conveyor 5 Metal electrode roll 6
Soft conductive roll 7 Conductive material

Claims (1)

[Claims] 1. A withstand voltage test is performed by passing prepreg, which is an insulator, between two upper and lower rolls.The withstand voltage of prepreg is characterized by using metal or soft conductive material for the rolls and being able to change the pressure between the rolls. Test equipment.