JPH09131790A - Sheet surface treating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sheet having desired embossed pattern and excellent surface smoothness even when a sheet to be treated is made of stock material having a rich elastic restoring force such as foam sheet or the like. SOLUTION: A pressing endless belt 4 is stretched among a treating roll 1, a driving roll 2 and an adjusting roll 3, both of which are arranged so as to pinch the treating roll 1. In a pressing part 8, which is formed between the cylindrical and peripheral surface of the treating roll 1 and the pressing endless belt 4 over the domain ranging from the driving roll and the adjusting roll, sheets to be treated 6 and 7 are fed so as to be run under the pressed state during the pressing part 8 in accordance with the rotation of the treating roll 1 and finally separated from the pressing part 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet surface treatment method for subjecting a synthetic resin or rubber sheet surface to secondary processing such as glossing and patterning.

[0002]

2. Description of the Related Art Conventionally, as a method of embossing the surface of a synthetic resin sheet, for example, Japanese Patent Laid-Open No. 63-10104.
Japanese Patent Application Laid-Open No. H4-A4 discloses a technique in which a sheet in a heated / softened state is fed into an apparatus including an embossing roll and a pressing roll that is elastically pressed by an endless belt. Japanese Patent Publication No. 107502 discloses a technique in which a sheet is similarly fed into an apparatus including an endless belt for embossing and an elastic roll to perform embossing.

[0003]

In the case of these techniques,
The contact / press between the embossing roll and the pressing roll, or the contact / pressing between the embossing endless belt and the pressing roll is performed in a line contact state, so full-scale application of the pressing force to the sheet to be processed is instantaneous. Therefore, the pressing effect is small.

Therefore, if the sheet to be treated is a relatively thin and non-elastic body, there is little problem, but the sheet to be treated is a thick and highly elastic material such as a foamed sheet or a rubber sheet. When it consists of, the embossed pattern tends to become shallow or collapse due to its elastic restoring force. In order to prevent this as much as possible, it is conceivable to deepen the engraving roll or the processing endless belt, but this causes a cost increase. Further, if the line contact is used, the cooling effect is relatively small, resulting in poor smoothness.

The present invention solves the above-mentioned disadvantages of the prior art,
Provided is a sheet surface treatment method capable of obtaining a desired embossed pattern and having excellent surface smoothness even when the sheet to be treated is made of a material having a high elastic restoring force such as a foamed sheet. The purpose is to do.

[0006]

According to the sheet surface treatment method of the present invention, a sheet to be treated is provided on a surface of a treatment roll or a treatment endless belt in accordance with a rotation of the treatment roll or the treatment endless belt. It is characterized in that the vehicle travels in a pressed state for a distance ", whereby the above object is achieved.

The treatment referred to in the present invention is a mechanical treatment such as applying a pressing force to a sheet to be treated in a heated / softened state to give an embossed pattern or a smooth surface.

As the material of the processing roll or the processing endless belt used in the present invention, an appropriate material is selected and used according to the type and speed of the processing, the magnitude of the pressing force received, etc. A metal material having high thermal conductivity is preferable.

In the present invention, as a means for pressing the sheet to be processed against these processing rolls or processing endless belts, it is preferable to use pressing rolls or pressing endless belts. In the case of processing rolls, As shown in FIG. 1, a driving roll 2 and an adjusting roll 3 are arranged on both sides of a processing roll 1 having a relatively large diameter, and a pressing endless belt 4 is provided between the driving roll 2 and the adjusting roll 3. This endless belt for pressing 4
However, it is preferable to use an apparatus in which the processing roll is in contact with the circumferential surface of the body in a circular arc shape and cooperates while the processing roll is rotating.

In the case of a processing endless belt,
As shown in FIG. 2, the pressing endless belt 4 is adopted,
When the processing endless belt 10 rotates, tension is applied inside the rotation of the pressing endless belt 4 and the processing endless belt 10 so that the processing endless belt 10 travels for a certain distance while being pressed against the outer surface thereof. The adjusting roll 11 is provided.

The processing roll 1 or the processing endless belt 10 and the driving roll 2 need to rotate at substantially the same speed. Therefore, it is arbitrary to use a speed tuning device using a computer. However, of course, the speed may be adjusted manually.

In the present invention, the target sheet to be surface-treated is not particularly limited, but polyethylene, polypropylene, ethylene-propylene copolymer,
Ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinyl acetate, polystyrene, acrylonitrile-butadiene-styrene copolymer, thermoplastic resin such as acrylonitrile-styrene copolymer, a sheet made of natural rubber, synthetic rubber, or the like, or These foamed sheets include, in the case of lamination processing, in addition to those made of the above plastic material,
Sheets made of all kinds of materials such as paper, cloth and metal foil can be used together. In any case, as mentioned above,
When used for the surface treatment of a relatively thick sheet having high elasticity, a more remarkable effect is exhibited.

In the present invention, the sheet to be treated needs to be heated and softened before feeding the sheet to be treated to the processing roll or the processing endless belt. It is effective to use the cured sheet as it is, but the sheet once molded may be reheated.

[0014]

According to the sheet surface treatment method of the present invention, the sheet to be treated is run on the surface of the treatment roll or the treatment endless belt in a pressed state for a predetermined distance in accordance with the rotation of the treatment roll or the treatment endless belt. Therefore, full-scale pressing force for the surface treatment of the processed sheet is continuously applied for a certain period of time, and even if the processed sheet is thick and highly elastic, its thickness and elasticity are Can be applied and necessary and sufficient surface treatment can be performed.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Example 1) FIG. 1 is a schematic explanatory view showing an example of an apparatus suitable for carrying out the sheet surface treatment method of the present invention.

In FIG. 1, reference numeral 1 is a processing roll having a depth of 30 for forming a skin pattern on its surface.
A 0 μm concave pattern is engraved with an outer diameter of 300 mm,
It is made of a metal drum having a length of 800 mm, and a coolant or heat medium made of water, oil or the like circulates in the inner cavity, and is rotatable in the arrow direction.

Reference numeral 2 is a drive roll for pressing the pressing endless belt 4 against the processing roll 1 via the sheet to be processed and driving the pressing endless belt 4. An adjusting roll 3 is disposed diagonally below the drive roll 2. This adjusting roll 3 can reciprocate its position in the direction of arrow A or arrow B by a moving mechanism (not shown) to adjust the pressing distance, pressing force or tension of the pressing endless belt. In the case of the example, the linear distance between the driving roll 2 and the adjusting roll 3 is 400 mm, and it is reciprocally movable in the direction of arrow A. Further, the driving roll 2 and the adjusting roll 3 are also capable of circulating cooling water in the internal cavity.

The pressing endless belt 4 has a thickness of 0.
The belt is made of a steel belt having a width of 2 mm and a width of 800 mm, the surface of which is subjected to rust prevention plating, and is stretched between the drive roll 2 and the adjusting roll 3. The drive roll 2 and the adjusting roll 3 are rotatable in the direction of the arrow. The peripheral speed of the processing roll 1 and the traveling speed of the pressing endless belt 4 of this device are manually adjusted. Reference numeral 5 is a T die attached to the tip of an extruder (not shown).

Using the above apparatus, polypropylene having a softening point of 100 ° C. was melted and kneaded by an extruder, and a first sheet 6 having a width of 700 mm and a thickness of 300 μm was extruded from the T die 5. The resin temperature when discharged from the T die 5 is 215 ° C.
Met. On the other hand, a preformed polypropylene foam having a width of 700 mm and a thickness of 2.0 mm (foaming ratio = 25
A second sheet 7 composed of a double end) is fed from the drive roll 2 side and runs between the drive roll 2 and the adjusting roll 3, and a corresponding peripheral surface of the processing roll 1 The pressing portion 8 formed by was passed through and released. The take-up speed was 1.0 m / min. Further, cooling water of 50 ° C. was circulated in the processing roll 1, and cooling water of 20 ° C. was circulated in each of the driving roll 2 and the adjusting roll 3.

The average depth of the skin pattern of the obtained laminated sheet 9 was measured and found to be 272 μm. The surface was randomly measured at 10 locations using a microscope, and the average depth was defined as 1/2 of the sum of the shallowest portion and the deepest portion.

(Embodiment 2) FIG. 2 is a schematic explanatory view showing another example of an apparatus suitable for carrying out the sheet surface treatment method of the present invention.

In FIG. 2, reference numeral 10 denotes an endless belt for processing, which is made of a steel belt having a width of 800 mm and a thickness of 0.3 mm, and is substantially arranged between three driving rolls 2, 2 and 2 each having an outer diameter of 100 mm. It is stretched in a triangular shape,
On its surface, a concave pattern for engraving a skin print pattern having the same pattern as that of the processing roll 1 used in Example 1 is engraved. In addition, cooling water can be circulated inside the inner cavities of the respective drive rolls 2, 2 and 20 ° C. in this embodiment.
Cooling water was circulated. The linear distance between the lower drive rolls 2 in the drawing is 300 mm.

The pressing endless belt 4 is stretched between the driving roll 2 and the adjusting roll 3 and has substantially the same structure as that of the first embodiment. The linear distance between the driving roll 2 and the adjusting roll 3 is the same. Is 400 mm. A tension adjusting roll 11 is for adjusting the tension of the pressing endless belt 4, and its position can be shifted by a tension adjusting mechanism (not shown) so that the pressing endless belt 4 is always tensioned. Is adjusted. Thus, the pressing endless belt 4 can press the processing endless belt 10 while rotating in the arrow direction.

Using the above-mentioned apparatus, the first sheet 6 and the second sheet 7 are fed under the same resin and molding conditions as in Example 1, and run between the drive roll 2 and the adjusting roll 3. The pressing portion 8 formed by the pressing endless belt 4 and the corresponding surface of the processing endless belt 10 was passed.

The average depth of the skin pattern of the obtained laminated sheet 9 was measured in the same manner as in Example 1, and the result was 275 μm.
m.

(Comparative Example) In the apparatus shown in FIG. 1 used in Example 1, the adjusting roll 3 is moved in the direction of arrow B to separate the pressing endless belt 4 from the processing roll 1 and the state shown in FIG. A laminated sheet S was obtained in the same manner as in Example 1 except that the above was changed to. In this case, the pressing force received by the first and second sheets 6 and 7 is equal to the pressing endless belt 4
And was instantaneous due to the line contact between the treatment roll 1 and the treatment roll 1.

The average depth of the skin pattern of the obtained laminated sheet S was measured in the same manner as in Example 1 and was found to be 202 μm.
m. As described above, when the pressing force is applied instantaneously by line contact, the sheet to be treated, especially the second sheet 7, is separated at a temperature higher than the softening temperature due to the influence of the restoring force and insufficient cooling. As a result, the desired embossed pattern was not obtained.

The apparatus shown in FIGS. 1 and 2 used in the above embodiment shows an example of an apparatus in which embossing and laminating are performed at the same time, but it can be used only for embossing. In addition, if the surface of the processing roll or the processing endless belt is mirror-finished, it can be used as a device for glossing the surface or imparting smoothness.

[0030]

According to the sheet surface treatment method of the present invention, the pressing force for surface treatment of the sheet to be treated is continuously applied for a certain period of time, so that the sheet to be treated is thick and rich in elasticity. Even if it is a thing, it can overcome the thickness and resilience and can perform necessary and sufficient surface treatment.

Therefore, a product having excellent quality such as embossed pattern, smoothness, and stretch resistance of the sheet itself can be obtained. Further, in the case of embossing, it is economical because it is not necessary to make the engraved pattern deeper than necessary. is there.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing an example of an apparatus suitable for carrying out the sheet surface treatment method of the present invention.

FIG. 2 is a schematic explanatory view showing another example of the same device.

FIG. 3 is an explanatory diagram showing a state when the apparatus shown in FIG. 1 is used in a comparative example.

[Explanation of symbols]

 1 Processing Roll 2 Driving Roll 3 Adjusting Roll 4 Pressing Endless Belt 6 First Sheet 7 Second Sheet 8 Pressing Section 9 Laminated Sheet 10 Processing Endless Belt 11 Tension Adjusting Roll

Claims (1)

[Claims] 1. A sheet surface, wherein a sheet to be treated is run on a surface of a processing roll or a processing endless belt in a pressed state for a predetermined distance in accordance with the rotation of the processing roll or the processing endless belt. Processing method.