TECHNICAL FIELD

The present disclosure relates to a waterproof sound-transmitting sheet, and more specifically, to a waterproof sound-transmitting sheet for facilitating a vision inspection for reading defects due to foreign matters and wrinkles.

BACKGROUND ART

Recently, the use of a mobile electronic device such as a portable terminal, a digital camera, or a notebook computer is increasing day by day. Since such a mobile electronic device is used while carrying, the mobile electronic device is likely to fall into water, thereby requiring a waterproof function. That is, a portion where a speaker, a microphone, or the like is installed is formed with an acoustic hole for emitting sound, and water or dust permeates into the electronic device through the acoustic hole.

Therefore, the acoustic hole is installed with a waterproof sound-transmitting sheet for passing through sound and blocking water or dust. Such a waterproof sound-transmitting sheet should be manufactured in consideration of all of waterproof and sound transmission efficiency.

Defects of a product such as whether foreign matters such as pinhole and dust exist and wrinkles should be read by a vision inspection after the waterproof sound-transmitting sheet is manufactured, in which the waterproof sound-transmitting sheet is mainly manufactured in white, such that there is a problem in that it is difficult to read foreign matters and wrinkles through the vision inspection.

SUMMARY OF INVENTION

Technical Problem

The present disclosure is proposed to solve the above conventional problem, and an object of the present disclosure is to provide a waterproof sound-transmitting sheet for facilitating a vision inspection, which radiates a polymer material and a pigment in a blended state to form a waterproof layer having a color, thereby facilitating the vision inspection, and improving water repellency even while making the waterproof sound-transmitting sheet thin and light.

Solution to Problem

To achieve the object, a waterproof sound-transmitting sheet for facilitating a vision inspection according to an exemplary embodiment of the present disclosure includes an upper waterproof layer composed of a porous membrane, a lower waterproof layer composed of the porous membrane and disposed under the upper waterproof layer, and an acoustic layer composed of the porous membrane and interposed between the upper waterproof layer and the lower waterproof layer, in which the porous membrane of at least one of the upper waterproof layer and the lower waterproof layer is a porous colored membrane having a color other than white and black.

At this time, the porous colored membrane may be an achromatic color other than white and black, and for example, is gray.

The porous colored membrane may be formed by electrospinning a mixture of a pigment and a polymer material, and a color of the pigment may be one of black and white. A rate of adding the pigment is 0.5 wt % or more and 5 wt % or less based on the mixture. The polymer material may be one of polyvinylidenefluoride (PVDF) and polyurethane (PU), and a color of the polymer material may be white.

The porous colored membrane may have a coating material coated on a surface of a fiber.

The upper waterproof layer and the lower waterproof layer may be a porous colored membrane in a straight shape having a fiber structure with fewer curves than that of the acoustic layer.

The porous membrane of the acoustic layer may be a porous colored membrane of a color formed by electrospinning a polymer material mixed with a colored pigment, or a porous colored membrane of an achromatic color formed by electrospinning a polymer material mixed with a black pigment. At this time, the acoustic layer may be a porous membrane having a fiber structure in a spring shape with more curves than those of the upper waterproof layer and the lower waterproof layer.

Advantageous Effects

According to the present disclosure, the waterproof sound-transmitting sheet for facilitating the vision inspection may interpose and form the acoustic layer between the colored waterproof layers other than white and black, thereby facilitating the vision inspection and improving the water repellency even while making it thin and light.

Further, the waterproof sound-transmitting sheet for facilitating the vision inspection may differently electrospin the physical structures (i.e., fiber structures) of the waterproof layer and the acoustic layer, thereby improving all of the waterproof performance and the acoustic properties.

Further, the waterproof sound-transmitting sheet for facilitating the vision inspection may blend and radiate the polymer material in the state of including the pigment, thereby improving the waterproof while implementing the color other than white and black without increasing the weight.

