JPS584222B2 - antistatic belt - Google Patents

Description

[Detailed description of the invention] This invention relates to an antistatic belt.

In general, power transmission belt bodies such as (1) belts and timing belts are molded from rubber or polymer compounds, so they are easily charged with electricity during mounted operation, and moreover, the higher the load and the higher the speed of operation, the more severe the charge becomes.

Therefore, conventionally, as a means for preventing static electricity on belts as described above, carbon black with good conductivity, such as furnace carbon black or acetylene carbon black, is blended with a woven fabric for covering the outer layer and a rubber composition is applied thereto. Sometimes applying conductive paint or rubbing a conductive substance onto the side surface of the main body,
In the former case, the rubber composition applied to the woven fabric peels off when the belt is used, and the antistatic effect is quickly lost.In the latter case, as in the former case, early wear of the conductive material cannot be prevented. However, it has the disadvantage that sufficient effects cannot be expected.

On the other hand, a mixture of conductive fibers may be used in the woven fabric covered in the outer layer of the belt, or conductive fibers may be wrapped around a reinforcing core embedded within the belt. Due to the difference in performance, the strength of the blended woven fabric decreases, the durability of the belt body as a whole decreases, and the manufacturing of the woven fabric becomes considerably difficult.

In view of the above-mentioned drawbacks, the present invention has been made for the purpose of providing an antistatic belt that can maintain a sufficient antistatic function over a long period of time and is extremely easy to manufacture. The content of conductive fine particles between the fibers is 0.3% based on the dry weight of the woven fabric.
It is characterized in that it is configured so that it is uniformly mixed and held as described above.

Next, the present invention will be explained with reference to examples.

FIG. 1 is a cross-sectional view of one embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the main part of FIG. 1 enlarged microscopically.

The antistatic belt 1 of the present invention is a woven fabric 1 for outer layer covering formed by a woven fabric made of non-conductive fibers such as cotton, nylon, Tetron, etc. alone or in a blended yarn, and a mixed woven fabric of a combination of the former yarns.
As shown in FIG. 2, fine particles 13 of a conductive substance such as aluminum, copper powder, furnace carbon black, acetylene carbon black, etc. Woven fabric 11
The composition is uniformly mixed and maintained at 0.3% or more, preferably 1 to 10%, based on the dry weight.

The reason why the content of fine particles 13 is set to 0.3% or more is because if the content is less than this, sufficient conductivity cannot be obtained, and if it is set to 10% or more, as shown in FIG. This is because while there is not much change in the properties, the flexibility of the woven fabric decreases and it becomes more likely to break.

The mixing of conductive material particles 13 into the woven fabric 11 is achieved by mixing the woven fabric 11 with a liquid containing uniformly dispersed conductive material particles 13 such as furnace carbon black, acetylene carbon black, aluminum, and copper powder. The microparticles 13 are immersed in the liquid, and the fine particles 13 are permeated with the liquid, followed by drying.

Specific examples of the liquid in which the fine particles of the conductive substance are dispersed include, for example, 126 parts by weight of fine particles of aluminum, copper fine powder, furnace, or acetylene carbon black, 12.6 parts by weight of dispersant, and 12% caustic soda. .6
Parts by weight, 95.4 parts by weight of water were added, mixed and stirred, and the resulting mixture was used as a raw material liquid.To 5000 parts by weight of this raw material liquid, 29105 parts by weight of water, 420 parts by weight of penetrant, and an acrylic emulsion (38% ) to 1,000 parts by weight of the above raw material solution, add 33,280 parts by weight of water, 420 parts by weight of penetrant, and 300 parts by weight of rubber latex and mix and stir. liquid etc. are used.

As shown in FIG. 2, the woven fabric dipped in the liquid and dried has carbon black fine particles 13 and solid content retained between the constituent fibers 12.

In addition, when the carbon black fine particles 13 are mixed in as described above, the cut surface of the woven fabric 11 shows a uniform black cross section due to the mixed carbon black, and therefore, the black dyeing process of the woven fabric 11 is difficult. It can also be omitted.

Although the case of the ■-type power transmission belt has been explained as the above example, other belts such as flat belts, timing belts, or conveyor belts may be used as long as they have a woven fabric coating layer on the outer layer. Needless to say, it can be implemented in the same way.

When conductivity tests were conducted on examples of the present invention, RA
M (Rubber manufactures ass.
-ociatoon), ISO (International
nalorganization for stand
ardization), JEM (Japan ele
critical manufacturing
ation) or BS (British stan-
For example, it has been confirmed that the conductivity is 6 MΩ or less at a distance of 216 mm between clips defined in the RMA standard.

When the belt was tested for changes in conductivity during use, the results shown in FIG. 4 were obtained, indicating that the belt of the present invention has remarkable durability.

That is, FIG. 4 shows the change in surface insulation resistance MΩ (vertical axis) with respect to running time (horizontal axis), and as shown in graph P, the surface insulation resistance MΩ (vertical axis) is almost constant regardless of the passage of running time. On the other hand, fabrics in which rubber containing a conductive substance such as carbon black is rubbed into woven fabric lose their conductivity over time as shown in graph Q, and the present invention It was confirmed that the material had a significantly better conductivity life.

As described above, in this invention, since a conductive substance is mixed and held between the constituent fibers of the woven fabric for covering the outer layer of the belt, there is almost no peeling or falling off of the conductive substance during use of the belt. Therefore, stable conductivity can be imparted over a long period of time, and manufacturing is simple as all that is required is to immerse the woven fabric in a liquid in which a conductive substance is dispersed and dry it. Since the woven fabric is colored black using carbon black, the dyeing process that was conventionally applied to the woven fabric in this type of belt can be omitted, contributing to labor savings in the manufacturing process. It has various effects such as:

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of an embodiment of the present invention, Fig. 2 is a cross-sectional view microscopically enlarging the main part of Fig. 1, and Fig. 3 is a cross-sectional view showing the presence of particles of conductive material. FIG. 4 is a graph showing the relationship between amount and conductivity, and FIG. 4 is a graph showing the relationship between usage time and conductivity. DESCRIPTION OF SYMBOLS 1... Antistatic belt, 11... Woven fabric for outer layer covering, 12... Constituent fiber, 13...
...Characteristic particles of conductive substances.

Claims (1)

[Claims] 1 Conductive fine particles are contained between the constituent fibers of the woven fabric for outer layer covering at a content of 0.3% based on the dry weight of the woven fabric.
An antistatic belt characterized in that it is configured to be uniformly mixed and held as described above.