JP2500861B2 - Composite sheet with antistatic and static elimination functions - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a fiber cloth sheet having antistatic and static elimination functions,
In particular, the present invention relates to a seat used as a surface material for an automobile seat.

<Prior Art> It is well known that an impact due to static electricity occurs when a vehicle gets off after a driving operation. This is because the human body is charged to a high potential by rubbing against the interior material (eg seat) inside the vehicle, and when this touches the conductor, a large amount of static electricity suddenly flows, that is, spark. It is a discharge phenomenon.

Conventionally, a means for weaving conductive fibers has been known as an antistatic measure for textile products. This type uses a mechanism in which static electricity charged in a textile product is collected in a conductive fiber and discharged from the tip of the fiber by corona discharge to eliminate electrostatic charge in the textile product. However, even if such a means is used, the corona discharge effect (current collection effect) of the textile product
It is not very satisfactory as a surface material for automobile seats, and the charging effect (condenser effect) of the conductive fiber itself is extremely small. For example, due to contact with other objects such as a human body charged at high potential, There is little expectation that static electricity will escape to the sheet and be removed.

Therefore, for the purpose of static elimination effect, a conductive backing agent layer (surface resistance of 10 ⁶ Ω or less) containing 20% to 50% of carbon fine particles is integrated on the back surface of the fiber sheet mixed with the conductive fiber, and the backing agent is integrated. A grounded layer has been proposed as a static elimination sheet (Actually developed 60-40497).
issue). However, for example, when the seat is used as a surface material of a car seat, when the seat and the human body are in contact with each other from the beginning, the static electricity charged on the seat and the human body always flows through the conductive fiber and the backing agent layer to the vehicle body to eliminate static electricity. Therefore, the electrostatic potential of both does not rise, but when the human body separates from the sheet, the static electricity elimination route on the human body side caused by peeling of the sheet and the human body (clothes) or friction is cut off, It is recognized that the human body is charged to a high electric potential, and a remarkable spark discharge is generated when the sheet and the human body are recontacted. A phenomenon similar to this occurs when a human body charged to a high potential due to another cause comes into contact with the sheet. Such a phenomenon is the same as the spark discharge when a human body charged at a high potential comes into contact with a good conductor such as metal. Therefore, it cannot be said that the seat is effective as an antistatic and static elimination sheet for vehicles.

<Problems to be Solved by the Invention> In the present invention, in the process in which a charged body such as a human body charged to a high potential in a vehicle comes into contact with the sheet, the potential of the charged body is set to a level equal to or lower than a potential for spark discharge before the contact. An interior sheet for vehicles that has the function of rapidly removing static electricity from the charged body by conducting it after lowering and contacting, especially a sheet for surface materials of automobile seats, and a fiber composite sheet that has self-supporting electricity It provides a seat.

Further, the present invention provides a sheet having the antistatic property and the static eliminability which are required as an interior sheet for a vehicle, and yet the flexibility which is required as a surface material for a vehicle seat. Further, the present invention provides an antistatic / static elimination sheet that can be used for other than vehicle applications.

<Means for Solving the Problems> The present invention has a semi-conductive layer coated as a backing agent or laminated as a film on the back surface of a fabric layer in which pile yarns containing conductive fibers are arranged at intervals of 30 mm or less. A composite sheet in which the conductive fiber and the semiconductive layer are in contact with each other, wherein the conductive fiber has an electric resistance of 10 ⁵ to 10 ⁹ Ω
/ cm, and the surface resistance of the semiconductive layer is 10 ⁶ to 10 ¹⁰ Ω, which is a composite sheet having antistatic and static elimination functions.

First, the fiber layer in the present invention is a woven / knitted fabric or a non-woven fabric having pile yarns mainly composed of ordinary synthetic fibers, and conductive fibers are mixed into at least a part of the pile yarns or conductive fiber yarns are interwoven. It was done.

As the conductive fiber used in the present invention, carbon,
Fiber made of polymer mixed with conductive powder particles such as metal,
Examples of the composite fiber include a polymer containing these conductive powder particles and a polymer containing substantially no conductive powder particles. Chemical fibers with a metallic surface, metal deposited inside the fibers, and fine metal wires are also used as conductive fibers, but these fibers generally have an electrical resistance of 10 ^{5 as} described below.
Since it is less than Ω / cm, these conductive fibers cannot be generally used in the present invention in terms of electric resistance. In the present invention, in particular, in order not to impair the aesthetic appearance and feel of the fiber material, and for the purposes of the present invention, the polymer containing conductive powder particles such as carbon substantially contains conductive powder particles. Composite fibers such as those surrounded by a non-polymer layer are useful. The conductive fibers are preferably used in filament form. Furthermore, it is more useful to use the conductive fiber in a mixed or twisted state with other fibers, rather than using it alone, in order not to impair the aesthetic appearance and feel of the fiber material.

Further, as the conductive fiber, one having an electric resistance of 10 ⁹ Ω / cm or less is preferable in terms of the static elimination effect by current collection, but 10 ⁵ Ω / cm
If it is less than the range, shock due to electric shock will occur, so that a range of 10 ⁹ to 10 ⁵ Ω / cm is used in the present invention. Even in the case of a fiber made of a polymer in which conductive powder particles such as carbon and metal are mixed or a composite fiber containing the polymer as described above, the electric resistance value greatly changes depending on the amount of the conductive powder particles added. Therefore, it is necessary to add the conductive powder particles so that the electric resistance value is within the above range.

It is not necessary to use a mixed fiber or a mixed twist of the above conductive fiber and another fiber as all of the fiber materials.
The conductive fiber may be 0.05 to 5.0% by weight. When the content of the conductive fiber is 0.05% by weight or less, sufficient current collecting and corona discharge effects cannot be obtained, and when the content is 5% by weight or more, the effect is saturated and no significant improvement can be observed.

In the present invention, it is important that the conductive fibers are arranged so as to form the conductive protrusions with a certain density or more with respect to the surface of the semiconductive layer. Must be woven or knitted, for example, as warp yarns, weft yarns, or pile yarns, etc., arranged at intervals of 30 mm or less on the fabric. Is. The conductive protrusion has a function of lowering the potential of the charged body by corona discharge to some extent by collecting current on the sheet immediately before contact when the charged body charged at a high potential comes close to the surface. It is preferable to use a pile fabric, particularly a pile fabric, and a fabric fabric in which conductive fibers are arranged in both the ground yarn and the pile yarn. In order to have such a function, it is effective that the diameter of the conductive fiber is 50 μm or less.

The semiconductive layer in the present invention is formed by coating the back surface of the fabric layer as a backing agent or laminating it as a film or the like. As the backing agent, an ordinary backing resin or rubber in which electrically conductive powder particles or substances such as carbon or metal are finely dispersed is used, and as the film, similarly, electrically conductive fine particles or the like is mixed. To be

The semiconductive layer needs to have a surface resistance of 10 ⁶ to 10 ¹⁰ Ω. When it is 10 ¹⁰ or more, it is difficult to remove the charge by contact with a charged body, and when it is 10 ⁶ Ω or less, the layer is Becomes closer to the conductor, and spark discharge occurs between the sheet and the sheet depending on the potential of the charged body, which is not preferable. The backing agent can be easily obtained by, for example, finely dispersing carbon powder particles in an ordinary backing resin in an amount of 1.5 to 5% by weight based on the weight (solid content) of the resin agent. Similarly, in the case of a film, it can be easily obtained by adjusting the amount of conductive powder particles or substances mixed.

Generally, when conductive powder particles are added to the resin, the flexibility of the resin layer obtained from this resin mixture is halved, and when it is used as a seat surface material, the flexibility of the seat is impaired and the sitting comfort is deteriorated. In order to prevent such a case, it is effective to form the resin layer by a foam coating method or a mesh coating method (including dot-shaped, linear, mesh-shaped coating).

In the present invention, it is necessary that the conductive fiber and the semiconductive layer are in contact, and if they are not in contact, the corona discharge ability of static electricity collected in the fabric layer is reduced and at the same time the semiconductive property is reduced. The leakage effect to the layers will also be reduced. In addition, it is preferable that the electric resistance value of the conductive fiber is lower than the surface resistance value of the semiconductive layer from the viewpoint of the effect of leakage to the semiconductive layer.

Further, in the present invention, it is preferable to remove the static electricity of the sheet collected from the charged body by grounding, and for this reason, the surface resistance is applied to the back surface of the sheet composed of the cloth layer and the semiconductive layer.
It is desirable to integrate a conductive layer of 10 ⁶ Ω or less.

As the conductive layer, a conductive film, a conductive cloth,
A metal sheet, a metal plate or the like is used. FIG. 1 is a cross-sectional view of a composite sheet having a moquette structure as a fabric layer and having antistatic and antistatic functions according to the present invention. In the figure, 1 is a general thread, 2
Is a pile yarn or ground yarn in which conductive fibers having a diameter of 50 μm or less are mixed or twisted, 3 is a fabric layer, 4 is a semiconductive layer,
Reference numeral 5 indicates a conductive layer.

<Operation> The composite sheet of the present invention shown in FIG. 1 is used by placing it on a grounded conductor, and the surface of the sheet may come into contact with a charged body such as a human body charged at a high potential. , First, immediately before contact, the static electricity of the charged body is collected in the conductive fibers of the fiber layer and the potential of the charged body is lowered by corona discharge,
Further, since the sheet of the present invention is not a conductor as a whole and gradually discharges static electricity and does not discharge at once, when the charged body comes into contact with the sheet surface without sparking, the electrostatic charge of the charged body is gentler than that of the conductor. Flow through the conductive fibers of the sheet into the semi-conductive layer and are neutralized by grounding. Therefore, when the high-potential charged body comes into contact with the sheet of the present invention, the charged body can be quickly destaticized without causing electrostatic damage such as electric shock and noise due to spark discharge.
When the potential of the charged body is low, the charge is removed only by contact with the sheet.

The sheet itself according to the present invention has an antistatic effect because the conductive fibers are mixed therein, and the static elimination function does not significantly charge the substance in contact with the sheet according to the present invention.

From the above functions, the seat of the present invention can be used as an interior material for a vehicle, for example, as a seat surface material, a door lining, an inside panel board, etc., but is particularly excellent as a surface material of a vehicle seat. In addition to these, it can also be used as a chair upholstery in a computer room, a door knob cover, a rug, a wall material and the like.

Example 1 In order to confirm the effect of the present invention, the following samples were experimentally evaluated. Sample (A) has a cross-sectional structure in which a polyester mocket is surrounded by a polyester polymer that does not contain a nylon polymer containing 26.5 wt% of acetylene black and has a thickness of 20 denier (a diameter of one filament is 32 μm).
The composite conductive fiber filament (electrical resistance of 10 ⁷ Ω / cm) is mixed and twisted to form one composite yarn at intervals of 2 cm and 2 for the vertical warp yarn.
Arranged at a ratio of 1 per cm (the ratio of the conductive fiber to the weight of the fiber material is 0.09% by weight), and on the back side of the layer is a semiconductive layer with a surface resistance of 4.4 × 10 ⁶ Ω (backing resin and carbon powder). Mixed with 1.7% by weight) (the conductive fiber is in contact with the backing layer),
Sample (B) is the one that is normally backed (non-conductive layer) on the fabric layer of sample (A), Sample (C) is the one that is normally backed on the fabric layer that does not contain conductive fibers, and (D) is Surface resistance of the fabric layer of sample (A) 10 ⁴
Ω conductor backing (carbon powder on backing resin
30% by weight mixed) (the conductive fiber and the backing layer are in contact with each other). These static elimination performances were evaluated. The results are shown in Table 1.

As shown in Fig. 2, the evaluation method is as follows: place the evaluation sample (12) (20 cm x 20 cm) on the earth plate (11) and press the discharge bulb (14) that has been boosted (5 kv) by the electromotive machine (13) in advance. It is performed by measuring the electric potential of the discharge sphere when the tip contacts the surface of the sample. However, the temperature and humidity conditions are 22 ℃ x 20
% RH. In FIG. 2, 15 is an insulator, 16 is an electrometer, 17 is a recorder, 18 is an electrode, 19 is a probe, and 20 is an insulator.

Each of the samples A to D was used as a surface material to manufacture an automobile seat. Then, the prepared seat is set in a car, and under the temperature condition of 0 ° C, a person wearing polyester shirts and polyester trousers is seated on the seat, and the hips are made to reciprocate back and forth, left and right for 10 seconds, and the seat and clothes are put together. Rubbed and. Then, the human body potential when standing up from the seat was measured.

Sample A: 3.4kv Sample B: 8.6kv Sample C: 9.0kv Sample D: 3.3kv In the case of both Samples B and C, if you stood up from the seat and touched a conductive object (metal), a large electric shock would occur. Occurred. In the case of sample D, a large electric shock occurred when standing up from the seat. On the other hand, in the case of Sample A, only a slight electric shock was felt when the conductive material was touched.

Comparative Example Conductive fiber with 10 Ω / cm stainless fine fiber (15
A composite sheet was produced in the same manner as in Sample A except that μ) was used. When this sheet was used as a surface material for automobile seats, it was accompanied by a large shock due to electric shock at the time of contact due to the capacitor effect with the conductor layer.

On the other hand, in the conductive fiber used in Sample A as the conductive fiber, the addition amount of acetylene black was 20 wt%.
A composite sheet was prepared in the same manner as in Sample A, except that the same was used. The electric resistance of the conductive fiber is 10 ¹⁰ Ω / cm. This sheet leaked the charged human body potential very slowly, and as a result, had almost no static elimination effect.

Example 2 In the production method of Sample A of Example 1, as a semi-conductive layer, a resin liquid (2.0% by weight of carbon powder, which was previously foamed) was used.
A sheet was prepared in the same manner as Sample A, except that the back surface of (including) was applied and dried. At this time, the bubble content of the semiconductive layer was 65% by volume. The thickness of the semiconductive layer was 95 g / m ² . When a seat using this sheet as a surface material was produced, it was extremely excellent in terms of antistatic and static elimination properties as in Sample A,
Furthermore, the seat itself was extremely flexible, and the seating comfort when used as a seat surface material was extremely good.

<Effect> According to the present invention, the potential of the charged body is lowered to a potential at which spark discharge does not occur immediately before contact with the sheet, and then the charge is rapidly removed from the charged body.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an example of the composite sheet of the present invention, and FIG. 2 is a diagram of an apparatus for measuring the static elimination performance of the sheet.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-59-192559 (JP, A) JP-A-60-140698 (JP, A) JP-A-58-33453 (JP, A) Actual development Sho-57- 129483 (JP, U)

Claims (2)

(57) [Claims] 1. A semiconductive layer is coated as a backing agent or laminated as a film on the back surface of a fabric layer in which pile yarns containing conductive fibers are arranged at intervals of 30 mm or less, and the conductive fiber and the semiconductive layer are laminated. A composite sheet in contact with a conductive layer, wherein the conductive fibers have an electric resistance of 10 ⁵ to 10 ⁹ Ω.
/ cm, and the surface resistance of the semiconductive layer is 10 ⁶ to 10 ¹⁰ Ω, a composite sheet having antistatic and static elimination functions. 2. The vehicle composite sheet according to claim 1.