JPH08268608A - Wrinkle-stretching roll - Google Patents

Abstract

PURPOSE: To solve a problem regarding the charging of static electricity by forming the surface of a wrinkle-stretching roll provided with spiral grooves with an optimum material which hardly generates the static electricity in a sheet material. CONSTITUTION: A wrinkle-stretching roll 11, which transfers a sheet like material by a roll surface covered with rubber and has a pair of wrinkle-stretching spiral grooves 13 both having lead angles oppositely inclined each other, is characterized in that the rubber surface on the roll surface is covered by a material 15 ranked to be lower than rubber in electric chargeability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wrinkle-rolling roll having a spiral groove on its surface, which is used for winding and conveying a sheet-like material.

[0002]

2. Description of the Related Art As a wrinkle-rolling roll for a sheet-like material, there is known a wrinkle-rolling roll having spiral grooves inclined in opposite directions of lead angles from the central portion of the roll surface in the longitudinal direction toward both ends. (For example, actual Kaihei 4
-60964). In such a wrinkle-rolling roll, the sheet material conveyed on the roll surface is subjected to a widening action from the central portion in the longitudinal direction of the roll toward both ends along the spiral groove in the direction in which the lead angles are opposite to each other. ,
Wrinkles are stretched in the width direction on the roll surface.

In this type of roll, the roll surface is generally made of an elastic material so as to have a wrinkle-stretching effect by the elastic restoring force of the walls on both sides of the spiral groove, in addition to the wrinkle-stretching effect by the lead angle of the spiral groove. Specifically, it is made of rubber, and the walls on both sides of the spiral groove are extended while being inclined in the roll radial direction.

However, when this roll is used, for example, in the winding section or the conveying section of a plastic film, the wrinkle of the film is satisfactorily extended by the action of the roll surface, but the roll is forcibly exerted. Therefore, more or less friction is generated between the film and the roll surface, and the friction charges the film with static electricity. If this amount of charge becomes large, it will cause troubles in the process, and if static electricity remains in the product, it will cause troubles such as repelling the coating material in the secondary processing, for example, the coating material coating process. Becomes Further, in general, static electricity is not uniformly charged, but is charged in a nonuniform state. In particular, in the wrinkle-rolling roll having the spiral groove as described above, charging corresponding to the pitch of the spiral groove is likely to occur. The uneven charging may cause local product defects and uneven quality especially in the secondary processing.

In order to deal with the problems associated with such electrostatic charging, a method is known in which a rubber constituting the roll surface is kneaded with a conductive substance such as carbon so that the roll surface has conductivity. . However, even if a conductive substance is kneaded, the roll surface is essentially formed of rubber, so it is difficult to sufficiently eliminate the problem of charging, let alone the problem of uneven charging. Absent.

[0006]

SUMMARY OF THE INVENTION The inventors of the present invention have made earnest studies on the above-mentioned problems by plasticizing up to the mechanism of static electricity generation, and as a result, as long as the roll surface is essentially formed of rubber, the electrostatic charge is prevented. It was found that there is a limit to the suppression, and in order to suppress the electrostatic charge to be small while taking advantage of the characteristics of the wrinkle-rolling roll with spiral groove as described above, the surface of the roll must be coated with a substance that is less likely to be charged. Furthermore, they have found that the amount of static charge is related to the so-called charging order, and have found that the above-mentioned substances that are less likely to be charged may be selected based on this charging order.

That is, it is an object of the present invention to eliminate the problems associated with electrostatic charging by forming the surface of a wrinkle-rolling roll with spiral grooves by using an optimum material that does not easily generate static electricity with respect to the sheet material being conveyed. .

[0008]

The wrinkle-rolling roll of the present invention for this purpose conveys a sheet-like material on a rubber-coated roll surface, from the longitudinal center of the roll surface toward both ends, In a wrinkle-rolling roll having a spiral groove inclined in a direction in which lead angles are opposite to each other, the surface of the rubber on the roll surface is coated with a substance whose charging order is located on the negative side of the rubber. Become.

The wrinkle-rolling roll according to the present invention is
A sheet-like material is conveyed on a rubber-coated roll surface, and from the longitudinal center of the roll surface to both ends, in a wrinkle-stretching roll having spiral grooves inclined in opposite lead angle directions, The surface of the rubber is coated with a substance having the same charging order as that of the sheet-like material or on the negative side of the sheet-like material.

That is, the basic technical idea of the present invention is that the spiral groove itself on the surface of the roll is made of rubber so that only the surface of the spiral groove wrinkle-rolling roll has the same wrinkle-extending characteristics as described above. That is, by forming only the surface that is in direct contact with the sheet-like material with a material having a charging sequence close to that of the sheet-like material, the amount of static charge of the sheet-like material is significantly reduced.

Here, the charging sequence refers to static electricity generated when two substances are rubbed with each other. Positively charged ones are positioned higher, and negatively charged ones are positioned lower, and various substances are positively charged. Ordered in the direction and the negative direction. In the context of the present invention, Table 1 lists typical substances capable of forming a roll surface.

[0012]

[Table 1]

As can be seen from Table 1, when the sheet-like material is, for example, a polyester film or a polyethylene film, and the surface of the spiral grooved roll is formed of rubber as in the conventional case, triboelectric charging occurs between substances that are considerably separated from each other. Therefore, a large amount of static electricity was generated. However,
Although the charging order and the electrostatic charge amount are not in a proportional relationship, it is a fact that the charging amount increases when the charging orders are far apart.

Therefore, if the surface of the roll is coated with a substance whose charging order is on the negative side of rubber, the amount of electrification becomes smaller than that of polyester film or polyethylene film. Ideally, static electricity is extremely unlikely to occur if the substance is positioned in the same charging order as the target sheet-shaped material. Further, according to the experiments conducted by the present inventors, surprisingly, even if the charging orders are slightly apart,
The conventional positive / negative relationship, that is, the positive / negative relationship between the roll surface rubber (positive side) and the sheet-like material (negative side in the case of a plastic film) is reversed, and the roll surface is positioned on the negative side of the sheet-like material. It was found that the charge amount of the sheet-shaped material can be significantly reduced by covering the sheet-shaped material with the positive side and the roll surface on the negative side.

For example, a polyester film or a polyethylene film may be coated with Teflon on the surface of a rubber roll having a spiral groove. As a result, the charge amount of the film can be significantly reduced.

However, since Teflon is known as a material having a low friction coefficient and good slipperiness, the reduction of the friction coefficient with the sheet material may also contribute to the reduction of the charge amount. .

The coefficient of friction between the roll surface coating material and the sheet-like material is preferably 1 or less, and more preferably 0.
It is preferably within the range of about 1 to 0.8, more preferably 0.5 or less.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a transporting and winding section of a plastic film 1 as a sheet-like material. After passing through the guide rolls 2, 3 and 4, the film 1
The sheet-shaped material roll 7 is wound on the winding core 6 while being pressed by the contact pressure roll 5 with a predetermined surface pressure.
The wrinkle-rolling roll that is the subject of the present invention can be applied to any one of the guide rolls 2, 3, and 4 as a transport roll or the contact pressure roll 5.

2 and 3 show a first embodiment of the wrinkle-rolling roll according to the present invention. In the figure, 11
The whole wrinkle-rolling roll is shown, and 12 is its axis. On the roll surface of the wrinkle-rolling roll 11,
Helical grooves 13 are formed from the central portion in the longitudinal direction toward both ends so as to be inclined in directions in which lead angles are opposite to each other. As shown in FIG. 3, the spiral groove 13 is formed by the rubber 14 on the surface of the roll, and each spiral groove 13 is
In the vertical cross section (cross section shown in FIG. 3), it rises while being inclined in the roll radial direction. That is, the rubber wall 14a between the spiral grooves 13 rises while being inclined in the radial direction of the roll, and exerts an elastic restoring force against the pressing force from the film 1, so that the wrinkle-extending effect of the spiral groove 13 can be promoted. Has become.

The surface of the rubber 14 on the roll surface is coated with the substance 15 whose charging order is located on the negative side of the rubber 14. In this embodiment, the coating material 15 is made of Teflon resin. Therefore, the charging order of the coating material 15 is located on the negative side with respect to the polyester or polyethylene film 1. Further, in this embodiment, the Teflon resin is coated with a coating.

The coating substance is not limited to Teflon, but may be another substance. A substance having a charging order closer to that of the film 1 is preferable, and among them, a substance having a charging order the same as that of the film 1 or on the negative side of the same is desirable.

In such a wrinkle-rolling roll 1, the charging order of the coating material 15 is much closer to the film 1 than the conventional rubber surface, or is located on the negative side of the film 1, so that the film 1 is formed. The charge amount of is extremely low. Further, since the amount of charge is extremely small, even if uneven charge occurs, the unevenness itself does not cause any problem.

Even when the substance 15 is coated, the spiral groove 13 formed by the layer of the rubber 14 appears on the roll surface substantially as it is, so that the spiral groove 13 widens the film 1 and smoothes wrinkles. The effect is maintained well. Further, the wrinkle-extending effect due to the elastic restoring force of the rubber wall 14a is secured as it is. As a result, the amount of static charge can be suppressed to an extremely low level while maintaining the good wrinkle-extending effect.

4 and 5 show a wrinkle straightening roll according to the second embodiment of the present invention. In the wrinkle-rolling roll 21 of the present embodiment, the substance 22 formed in the form of a sheet-like material is covered on the surface of the rubber 14 on the roll surface while being contractible in the roll radial direction. In the present embodiment, the substance 22 is formed of a synthetic fiber knit (for example, polyester knit), and the roll is covered with a tubular knit in a state where the diameter is once expanded, and the rubber 14 is made by utilizing the shrinkability of the knit itself. Is adhered and adhered to the surface of.

Even with such a construction, the spiral groove 13 basically appears on the roll surface and can exert its wrinkle-stretching action, and the elastic restoring force of the rubber wall 14a is also exerted as it is. Therefore, while the good wrinkle-stretching effect is maintained as it is, the amount of static charge on the film 1 is suppressed to an extremely low level by the coating material 22.

The sheet form of the substance 22 is not limited to the knit, but may be another woven form or a simple sheet tube form. Further, when the film 1 is a polyester film, if the material 22 is formed of polyester knit as described above, the film 1 and the material 2 are formed.
The charging order of 2 becomes substantially the same, and the electrostatic charge amount of the film 1 can be suppressed to an extremely low level.

[0027]

As described above, when the wrinkle-rolling roll of the present invention is used, the rubber surface of the wrinkle-rolling roll with a spiral groove is coated with a substance having a specific charging order, so that the spiral groove has no good effect. While maintaining the stretching effect as it is, the electrostatic charge amount of the sheet-like material can be significantly reduced, and the level of uneven charge can be reduced to a level at which there is no problem. Therefore, process troubles due to electrostatic charging and troubles in secondary processing can be eliminated.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a sheet conveying unit and a winding unit.

FIG. 2 is a front view of the wrinkle straightening roll according to the first embodiment of the present invention.

FIG. 3 is a partially enlarged sectional view of a part III in FIG.

FIG. 4 is a front view of a wrinkle straightening roll according to a second embodiment of the present invention.

5 is a partially enlarged cross-sectional view of a V part in FIG.

[Explanation of symbols]

 1 plastic film 2, 3 and 4 guide rolls as conveying rolls 5 contact rolls 6 winding cores 7 sheet-like rolls 11 and 21 wrinkle-rolling rolls 12 shafts 13 spiral grooves 14 rubbers 14a rubber walls 15 and 22 coating materials

Claims (6)

[Claims] 1. A wrinkle-rolling roll that conveys a sheet-like material on a rubber-coated roll surface and has spiral grooves inclined in opposite lead angle directions from the longitudinal center to both ends of the roll surface. 2. The wrinkle-rolling roll, wherein the surface of the rubber on the roll surface is coated with a substance whose charging order is located on the negative side of the rubber. 2. A wrinkle-rolling roll having a spiral groove, in which a sheet-like material is conveyed on a rubber-coated roll surface, and a spiral groove is inclined in opposite directions of lead angles from a central portion in the longitudinal direction of the roll surface toward both ends. 2. The wrinkle-smoothing roll, wherein the surface of the rubber on the roll surface is coated with a substance having the same charging order as that of the sheet-like material or on the negative side of the sheet-like material. 3. The wrinkle-rolling roll according to claim 1, wherein the substance is coated on the surface of the rubber with a coating. 4. The substance is formed in the form of a sheet, and the substance formed in the form of the sheet is covered on the surface of the rubber while having contractibility in the roll radial direction. The roll for wrinkle extension according to claim 1 or 2. 5. The wrinkle-rolling roll according to claim 1, wherein the wrinkle-rolling roll is a contact pressure roll that comes into contact with the surface of a sheet-shaped material roll that is being wound into a roll. 6. The wrinkle-rolling roll according to claim 1, wherein the wrinkle-rolling roll is a conveying roll that conveys a sheet-like material at a predetermined wrap angle.