JPS6040235A - Continuous plasma processing method and apparatus for thermoplastic resin - Google Patents

Abstract

PURPOSE:To perform a continuous plasma processing of a thermoplastic resin with a high productivity in a energy-saving manner by a method wherein a thermoplastic resin is introduced into vacuum plasma generation area for a low-temperature plasma processing via an area with the pressure boosted incrementally. CONSTITUTION:A thermoplastic resin charged into an extrusion molding machine 3 is molded by direct extrusion from an extrusion die 4 and introduced into a vacuum plasma processing chamber 1 as vacuum plasma generation area. A gas such as air, oxygen and nitrogen is introduced into the vacuum plasma processing chamber 1 from a gas introduction port 8 while the vacuum plasma processing chamber 1 is made vacuum by exhaustion through an exhaust chamber 9. Then, a thermoplastic resin sheet or film is introduced between electrodes 7 and 7' for a low-temperature plasma processing. The sheet or film thus subjected to the low-temperature plasma processing is cooled with a cooling roll 10 and then, introduced into a prevacuum chamber 6. Then, it is boosted in the pressure in the prevacuum chamber 1 incrementally and while approaching the atmospheric pressure, it is drawn out of the chamber 1 to be taken up with a take-up unit 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for continuous plasma treatment of thermoplastic resin, and more specifically, a method and equipment for continuous plasma treatment of thermoplastic resin in an energy-saving and highly productive process. The present invention relates to a processing apparatus that is simple, has low equipment costs, and is optimal for carrying out the continuous plasma processing method described above.

Conventionally, various chemical and physical treatment methods have been known for improving the adhesion, coating properties, printability, abrasion resistance, antistatic properties, etc. of molded products such as thermoplastic resin sheets and films. Among these processing methods, the plasma processing method is well known, and the low-temperature plasma processing method, which has particularly good operability, has recently been attracting attention.

This low-temperature plasma processing method is a dry process and requires a closed system apparatus because it is processed under high vacuum. Therefore, conventionally a batch processing method has been adopted, which poses a major problem in terms of practical application on an industrial scale. Therefore, various methods and devices have been developed to solve these problems.

For example, a continuous plasma processing method and its apparatus (Japanese Unexamined Patent Publication No. 57-67636), which consists of providing multiple zones with stepwise varying degrees of vacuum at the front and rear of a plasma processing chamber, Plasma continuous processing equipment (4F
- Publication No. 18737/1983).

However, these conventional methods and devices require devices to isolate the material from the atmosphere at two locations: the inlet and outlet of the material into the plasma processing chamber, resulting in high plasma processing costs and expensive equipment. Ta. Furthermore, it is difficult to heat the material to increase the treatment effect, and in particular, it has been impossible to heat the material above its softening point. Furthermore, materials such as films and sheets before plasma treatment are easily contaminated by dust, dirt, bacteria, etc., and a large amount of equipment is required to prevent this.

Therefore, the present inventors have developed a series h1 that eliminates the above-mentioned conventional drawbacks.
-As a result of intensive research to develop a plasma treatment method and treatment device, we have finally completed the present invention.

That is, the present invention is characterized in that a thermoplastic resin loaded in an extrusion molding machine is directly extruded and introduced into a vacuum plasma generation area, and is continuously taken out after passing through a region where the temperature is low in the vacuum plasma generation area. Continuous plasma treatment method for thermoplastic resin (first invention), and a thermoplastic resin comprising an extrusion die at the end of the vacuum plasma treatment chamber and a preliminary vacuum chamber at the outlet of the vacuum plasma treatment chamber, each in a sealed state. The present invention provides a continuous plasma processing apparatus (second generation [1)]).

The thermoplastic resin to which the present invention is applied is not limited to bamboo, and includes, for example, high-density polyethylene, low-density polyethylene, polypropylene, copolymers of two types of olefins, and copolymers of olefins and unsaturated carboxylic acids or derivatives thereof. Polymerefine such as polymer; polyester; polycarbonate; polyamide; general purpose polystyrene (ap-pB)
= High impact polystyrene (HI-1's), As
Examples include polystyrene resins such as resins, ABB resins, vinyl chloride resins, and acrylic resins. These thermoplastic resins may be used alone or in combination of two or more. Furthermore, thermoplastic resins are supplemented with various stabilizers (oxidation, heat, light, etc.), fillers (calcium carbonate, Merck, Crepe Yoto), and reinforcing materials (glass fiber, carbon fiber, etc.) as necessary.

Rubbers, lubricants, antistatic agents, plasticizers, etc. can be added as appropriate.

The above-mentioned thermoplastic resin is loaded into a known extrusion molding machine such as a single-screw extruder or a multi-screw extruder, and the loaded thermoplastic resin is introduced by extrusion molding directly into the plasma generation area, and the vacuum The thermoplastic resin can be subjected to continuous plasma treatment by performing low-temperature plasma treatment in a plasma generation region, and then continuously withdrawing the resin through a region where the pressure is increased stepwise.

Here, low-temperature plasma is non-equilibrium plasma, specifically, air, oxygen, nitrogen, etc. are generated by high-frequency discharge, glow discharge, microwave discharge, corona discharge, etc.

hydration, argon, helium, xenon, carbon dioxide gas.

It is obtained by activating methane, ethane, freon, etc., and mixed gases thereof. In this case, other polymerizable monomers (for example, α-olefins such as butene-1, unsaturated carboxylic acids such as acrylic acid, etc.) may also be allowed to coexist.

Low-temperature plasma treatment is performed at 0.005 to 20 Torr (Torr).
), preferably under a pressure of 0.02 to 5 torr, and the thermoplastic resin is treated with the resulting low-temperature plasma for a predetermined period of time, usually from 1 second to 10 minutes.

Hereinafter, the continuous plasma processing method of the present invention will be explained in more detail based on the continuous plasma processing apparatus of the present invention shown in FIG.

In the figure, reference numeral 1 denotes a vacuum plasma processing chamber, and an extrusion die 4 of an extrusion molding machine 3 is installed in the vacuum plasma processing chamber 2 in a sealed state. Further, a preliminary vacuum chamber 6 is installed in a sealed state at the outlet 5 of the vacuum plasma processing chamber.

The thermoplastic resin θ1 loaded in the extrusion molding machine 3 is directly extruded from the extrusion die 4 and introduced into the vacuum plasma processing chamber 1, which is a vacuum plasma generation area.

The thermoplastic resin sheet or film introduced from the extrusion die 4 into the vacuum plasma processing chamber 1 is subjected to low temperature plasma treatment in the vacuum plasma processing chamber. As the vacuum plasma processing chamber itself, a known one can be used, for example, as shown in the figure, electrodes 7, 7', gas introduction 1', 8. It is equipped with an exhaust pipe 9. Gas introduction 1 The above-mentioned gases such as air, oxygen, nitrogen, etc. are introduced through 8, and are exhausted through IJ + trachea 9 to bring the vacuum plasma processing chamber into a vacuum state. Then, the thermoplastic resin sheet or film is introduced between the electrodes 7° and 7' and subjected to low temperature plasma treatment. Low temperature plasma treatment ■1
After the thermoplastic resin sheet or film is cooled by a cooling roll 10, it is placed into a preliminary vacuum chamber 6.

As the preliminary vacuum chamber 6 itself, a known one can be used,
For example, as shown in the figure, the sealing chambers 6a, 6b, and 6cm-1 are made up of a pair of upper and lower rolls and a housing. The pressure is increased stepwise in the pre-vacuum chamber, and when it approaches atmospheric pressure, it is taken out from the pre-vacuum chamber and taken to the take-off device Ft]-x.

In this example, one extrusion molding machine was used, but it is also possible to extrude the thermoplastic resin from two or more extrusion molding machines and subject it to plasma treatment to obtain a laminate with the treated surface inside. .

In addition, a laminate can be obtained by introducing a rolled sheet or film produced in advance into the vacuum plasma processing chamber 1 or from outside the vacuum plasma processing chamber. When the material to be laminated is another thermoplastic resin, it is preferable that the resin is also subjected to low-temperature plasma treatment as described above, and the treated surfaces are pressed together and laminated.

The above-mentioned apparatus processes thermoplastic resin on bamboo in a softened state, that is, the thermoplastic resin is heated to a temperature below the melting point or softening point of the resin.
Although the method of the present invention is suitably used when molding by heating and melting at two temperatures and extruding, the method of the present invention can also be applied to ordinary low-temperature plasma treatment.

FIG. 2 is a schematic diagram without showing another embodiment of the continuous plasma processing apparatus used for the continuous plasma processing of the present invention.

In this embodiment, a chill roll 12 is provided near the entrance 2 of the vacuum plasma processing chamber 10. However, the thermoplastic resin sheet or film extruded directly from the extrusion die 4 into the vacuum plasma processing chamber 1 is cooled to below the melting point or softening point of the thermoplastic resin by the cooling hole 12 of the Afterwards, it is subjected to low temperature plasma treatment.

Incidentally, in performing the low-temperature plasma treatment, reheating can be performed by providing a ladle heating means as necessary.

As described above, according to the method of the present invention (first invention), since the thermoplastic resin is extruded and introduced from the extrusion die into the TM vacuum plasma treatment chamber, the thermoplastic resin is extruded and introduced into the TM plasma treatment chamber before the low temperature plasma treatment. Dust, dirt, germs, etc. do not adhere to the surface of the resin sort or film, and low-temperature plasma treatment can be performed in extremely good conditions.

Moreover, according to the method of the present invention, the thermoplastic resin can be treated at any temperature above its softening point, and there is no need for reheating, so there are practical effects such as energy saving. In addition, since only one set of vacuum chambers is required for shielding from the atmosphere, the equipment is simple, and continuous plasma treatment of thermoplastic resins can be carried out at low cost.

Further, according to the method of the present invention, the process from extrusion molding to surface treatment of the extruded thermoplastic resin sheet or fill can be carried out in an integrated continuous process, making it an extremely highly productive treatment method.

Further, according to the apparatus of the present invention (second invention), the method of the present invention having the above-mentioned characteristics can be carried out extremely efficiently.

Therefore, the present invention can be effectively used for manufacturing thermoplastic resin sheets or films.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing one embodiment of the continuous plasma processing apparatus of the present invention, and FIG. 2 is a schematic diagram showing another embodiment. 1...Vacuum plasma processing chamber. 2...Enter the vacuum plasma processing room [''. 3-・Extrusion molding machine. 4...Extrusion die. 5...Vacuum plasma processing chamber exit. 6...Preliminary vacuum chamber patent applicant Idemitsu Petrochemical Co., Ltd.

Claims (1)

[Claims] 1. The thermoplastic resin loaded into the extrusion molding machine is directly extruded and introduced into the vacuum plasma generation area, and the above ↓゛ is subjected to low temperature plasma treatment in the empty plasma generation area, and then stepwise 1. A method for continuous plasma treatment of thermoplastic resin, characterized by continuous plasma treatment of thermoplastic resin through a region where the pressure is increased. 2.) jl A continuous plasma processing apparatus for thermoplastic resin comprising an extrusion die at the entrance of the empty plasma processing chamber and a preliminary vacuum chamber at the exit of the vacuum plasma processing chamber, each in a sealed state.