JPS6190770A - Surface treatment of plastic sheet or film - Google Patents

Abstract

PURPOSE:To treat both surfaces with different treating liqs. by bringing a coater roll which is passed through an immersion vessel contg. a treating liq. into contact with one surface of a sheet, etc., dripping the treating liq. between a backup roll and a squeeze roll, and bringing the squeeze roll with the dripped treating liq. into contact with the other surface. CONSTITUTION:A plastic sheet or film 6 is brought into contact with a coater roll 7 and passed through an immersion vessel 5 contg. a treating liq., and one surface is coated with the treating liq. Then another treating liq. is dripped between a squeeze roll 12 and a backup roll 13, spread over the surface of the squeeze roll 12, brought into contact with the other surface of the sheet or film 6, and coated. Consequently, both surfaces of the sheet or film are coated with different treating liqs. by one process.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to a method of treating the surface of a synthetic resin sheet or film by applying a treatment liquid to the surface, and particularly relates to a method of treating the surface of a synthetic resin sheet or film. This method opens up a method in which different processing liquids are applied to both sides of the film and both sides are processed.

"Prior Art" When treating both sides of a synthetic resin sheet or film by applying different processing solutions to both sides, the processing solution is applied to one side of the synthetic resin sheet or film, dried, and rolled. After winding it up into a roll shape, a treatment liquid different from the above treatment liquid is applied to the other side of the rewound synthetic resin sheet or film, dried, and wound up into a roll shape.
The process was complicated and consisted of two steps.

"Problems to be Solved by the Invention" The present inventor has conducted research into a method of applying different treatment liquids to both sides of a synthetic resin sheet or film and treating both sides in one step. , arrived at the present invention.

``Structure of the Invention'' The present invention involves applying a processing liquid to one side of a synthetic resin sheet or film by passing the synthetic resin sheet or film through a dipping tank containing a processing liquid while contacting a coater roll, and then squeezing the synthetic resin sheet or film. The other side of the synthetic resin sheet or film is brought into contact with the other side of the synthetic resin sheet or film by contacting the squeeze roll, which has spread the processing liquid on the surface by dripping the processing liquid onto the contact area between the roll and the backup roll. The present invention relates to a surface treatment method for a synthetic resin sheet or film, characterized in that a treatment liquid different from the treatment liquid applied to one side is applied to one side.

Examples of the synthetic resin sheet or film include synthetic resin sheets such as biaxially oriented polystyrene sheets, and synthetic resin films such as polyethylene films and polypropylene films.

Examples of the treatment liquid include antifogging agents, mold release agents, antistatic agents, etc. According to the surface treatment method of the present invention, both sides of a synthetic resin sheet or film can be efficiently coated with different treatment liquids. can be processed.

FIG. 1 is an explanatory diagram showing an example of a method for surface treatment of a synthetic resin sheet or film according to the present invention.

The present invention will be explained below with reference to FIG.

A silicone mold release agent 2 is stored as a treatment liquid in a tank 1, and the water level of the mold release agent 2 in an immersion tank 5 is kept constant by supplying it through a water level regulator 4 equipped with a float valve 3. maintain. The release agent 2 is applied to one side of the biaxially oriented polystyrene sheet 6 as a synthetic resin sheet or film by passing it through a dipping bath 5 containing the release agent 2 without contacting the coater roll 7. do. Generally, the coating amount of mold release agent 2 is 1.0 to 5. Q
cc/td, and the moving speed of the biaxially stretched polystyrene sheet 6 is preferably 20 to 50 m/min.

While moving the biaxially oriented polystyrene sheet 6 upward, air is blown onto both ends of the biaxially oriented polystyrene sheet 6 through needle valves 8 while adjusting the amount of air. It is preferable to prevent the molding agent 2 from going around to the other surface.

A surfactant-based antifogging agent 10 is stored as a treatment liquid in a tank 9, and a predetermined amount is dropped through a metering pump 11 onto the central portion of the roll width at the contact area between the squeeze roll 12 and the backup roll 13. The antifogging agent 10 is spread on the surface of 12. In addition, when dropping the antifogging agent 10, the antifogging agent 10 is prevented from spilling from both ends of the roll by blowing air while adjusting the amount of air through the needle valves 14 at both ends in the width direction of the roll. is preferred. By passing the biaxially oriented polystyrene sheet 6 between a squeeze roll 15 and a squeeze roll 12 on which the antifogging agent 10 is spread, excess mold release agent 2 is scraped off from one side of the biaxially oriented polystyrene sheet 6. Antifogging agent 10 on the other side of the biaxially oriented polystyrene sheet 6
Apply. Generally, the amount of antifogging agent 10 applied is 0.5 to 2
．． It is preferable to set it to Q cc ′″/a.

Next, mold release agent 2 is applied to one side, and antifogging agent 1 is applied to the other side.
The surface treatment step is completed by passing the biaxially oriented polystyrene sheet 6 through a hot air dryer.

"Effects of the Invention" According to the present invention, the synthetic resin sheet or film 6
Since the method of treating both sides of the surface with different treatment liquids can be carried out in one step, the surface treatment can be carried out extremely efficiently.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an example of a method for surface treatment of a synthetic resin sheet or film according to the present invention. 2, 10-----1 treatment liquid, 5------1 immersion tank,
6-'----Synthetic resin sheet or film,
? -------- Coater roll, 12------ Squeeze roll, 13---1 Backup roll.

Claims (1)

[Claims] After applying the processing liquid to one side of the synthetic resin sheet or film by passing the synthetic resin sheet or film through a dipping tank containing the processing liquid while in contact with the coater roll, The treatment liquid is applied to one side of the other side of the synthetic resin sheet or film by bringing the other side of the synthetic resin sheet or film into contact with a squeeze roll on which the treatment liquid has been expanded by dropping the treatment liquid. A method for surface treatment of synthetic resin sheets or films, characterized by applying a treatment liquid different from that of the method.