JP3094379B2 - Multi-layer film having perfluoroalkoxy layer on one side - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A multi-layer film which adheres to the surface of a metal plate or an inorganic plate and has a perfluorinated alkoxy layer exposed on the surface side so that dirt can be easily wiped off.

[0002]

2. Description of the Related Art Conventionally, when a fluororesin film is adhered to a steel plate or the like, the fluororesin film has been directly adhered. However, since the melting point of the fluororesin is high, the steel sheet must be heated to a high temperature.
It will hurt both of the fluororesin films. Further, since cooling is performed from a high temperature, a problem that a peeling phenomenon occurs between the two remains.

Although it has been attempted to attach a fluororesin film to a steel sheet in advance instead of directly attaching the fluororesin film to the steel sheet, sufficient adhesion strength between the resin to be adhered to the steel sheet and the fluororesin film has been obtained. There is another problem that there is no.

[0004]

[PROBLEMS TO BE SOLVED] To obtain a multilayer film which can be bonded to a metal plate at a temperature lower than the melting point of a fluororesin and has a sufficient adhesive strength of the laminated multilayers.

[0005]

[Technical means] Perfluoroalkoxy layer PFA on the surface layer
Polyethersulfone PES or polyphenylene sulfide PPS resin and perfluoroalkoxy P
A multilayer film in which FA is mixed and the front and back layers are heat-sealed at about 280 ° C.

[0006]

The melting point of polyethersulfone PES or polyphenylene sulfide PPS is around 280 ° C., which is lower than the melting point of perfluoroalkoxy, so that it can be bonded to a metal plate at a low temperature.

Further, since the film is extruded at 280 ° C. on the back surface adhesive layer, the mixed perfluoroalkoxy PF
Since A remains in the back layer as powder particles, an intermolecular attractive force acts between the surface layer and the perfluorinated alkoxy PFA, and the adhesive strength of the front and back layers is secured.

[0008]

The resin used in the film of the present invention will be described first. PFA resin: a perfluorinated alkoxy resin having a structural formula shown in Chemical Formula 1.

[Chemical formula 1] The melting point is around 310 ° C. PES resin: polyether sulfone, the structural formula of which is shown in Chemical Formula 2.

[Chemical formula 2] The melting point is around 280 ° C.

PPS resin: polyphenylene sulfide, the structural formula of which is shown in Chemical Formula 3. To describe the definition of polyethersulfone, polysulfone having a bisphenol A residue (chemical formula 4) is also structurally polyethersulfone, but is generally called polysulfone.
Polysulfone (Chemical Formula 2) in which paraphenylene groups are alternately bonded by sulfone groups and ether groups is generally referred to as polyether sulfone, and polysulfone having biphenylene groups (Chemical Formula 5) is generally referred to as polyallyl sulfone. The two are distinguished.

[Chemical formula 4]

[Chemical formula 5]

[0010] The melting point is around 280 ° C. Polyphenylene sulfide (PPS) was established in 1973 by Ph.
The industrialization began with the construction of a 3000 ton annual production plant in Pogar, Texas by illips Petroleum. In the technology at that time, the melt viscosity of the PPS resin immediately after polymerization was very low, about 30 to 200 poise, and the molecular weight was low and brittle. Initially, it was developed mainly for paints, but was found to be useful as a resin for injection molding due to the increase in molecular weight by heat crosslinking reaction in the presence of oxygen, and started as one of special engineering plastics. PPS resin is a crystalline polymer having a melting point of about 280 ° C., and has attracted attention as a flame retardant resin having extremely high heat resistance and rigidity and excellent chemical resistance. In Japan, Phillips Pe is used.
The base resin was imported from troleum, and a glass fiber reinforcing material filler was kneaded and market development was conducted as a molding compound.
After the expiration of the basic patent of ps Petroleum, several others have put into operation PPS domestic production plants. As a result, the domestic base resin supply capacity is significantly excessive compared to the domestic market scale, and is a fiercely competitive market. In terms of quality, it is initially difficult to obtain PPS with a high degree of polymerization.
Improvements in moldability and mechanical properties were made. Recently, in order to improve the brittleness which is a drawback of the conventional crosslinked type, a linear type and a crosslinked type high toughness type have been developed together with a type emphasizing adhesion to metal and formability together with the type. On the other hand, new materials such as polythioethersulfone (PTES) and polythioetherketone, and polymer alloys with flexibility, low cost and high heat resistance are also being developed. is there.

The method for producing the composite film of the present invention will be described below. The present invention relates to a method for producing a multilayer film to be attached to a metal plate surface of a kitchen appliance such as a gas stove. In the first method , as shown in FIGS. 1 and 2, approximately 50 parts by weight of a polyether sulfone PES resin and a perfluoroalkoxy PFA are mixed and supplied to one extruder 2 of a T-die 1. I do. Then, extrusion is performed at an extrusion temperature that does not reach the melting point of the polyether sulfone PES resin. On the other hand, perfluoroalkoxy PFA is supplied alone to the other extruder 3 and extruded.

Then, the two are joined at the joining section 4 and adhered to form a multilayer film. At this time, the temperature is preferably about 200 to 250 ° C. which is lower than the melting point of the polyether sulfone PES so that the powder particles of the perfluoroalkoxy PFA in the back layer do not melt. The multilayer film thus formed is bonded by heating the metal plate to 200 to 265C.
s is a drawer roll. Polyether sulfone PE
Similar results were obtained when polyphenylene sulfide PPS was used instead of S.

Second Method In a second method shown in FIG. 3, a corona discharge treatment is performed on the back surface of a previously prepared perfluoroalkoxy PFA film f1.

On the other hand, a perfluorinated alkoxy PF
Approximately 50 parts by weight of A and polyether sulfone PES are mixed, supplied, and extruded. The extrusion temperature is 200 ~ 2
Since it is 50 ° C, the perfluoroalkoxy PFA in the back layer
Powder particles remain without melting.

After the back layer is cooled by the cooling roll 7 and drawn out by the drawing roll 8, it is guided by the guide roll 9 and merges with the surface layer. Then, they are melt-bonded by the hot-press roll 10. The heat pressure temperature is suitably from 200 to 250 ° C. 1
1 is a cooling roll, 12 is a drawer roll. In the second method, since the surface layer is subjected to corona discharge C, the adhesive strength of the front and back layers can be sufficiently secured at 200 to 250 ° C. Also, the powder particles of the perfluoroalkoxy PFA in the back layer are not broken.

Similar results were obtained by using polyphenylene sulfide PPS instead of polyether sulfone PPS.

Third Method A third method shown in FIG. 4 is to prepare a surface film f1 and a back film f2 in advance, combine them with a guide roll 13 and then apply heat and The rolls 14 and 14 are melt-adhered at 200 to 250 ° C. and fixed by cooling. Reference numeral 15 denotes a cooling roll. The structure is almost the same as the third method.

[0018]

[Effect] Polyether sulfone PES forming back layer
Alternatively, since the melting point of polyphenylene sulfide PPS is lower than that of perfluoroalkoxy PFA of fluororesin, the multilayer film of the present invention can be fused to a metal plate at a low temperature. Also, since powder particles of perfluoroalkoxy PFA remain in the back layer without being destroyed during the back layer molding process,
An intermolecular attractive force is generated between the perfluorinated alkoxy PFA on the surface layer and the front and back layers are not separated.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the multilayer film of the present invention,

FIG. 2 is a flow sheet of a first manufacturing method,

FIG. 3 is a flow sheet of a second production method,

FIG. 4 is a flow sheet of a third manufacturing method,

[Explanation of symbols]

f1: surface layer, f2: back layer, 1: T die, 2: back layer extruder, 3: surface layer extruder, 4: confluence part, 5: compression cooling roll, 6: back layer extruder, 7: cooling roll, 8: drawer roll, 9: guide roll, 10: hot press roll, 11: cooling roll, 12: drawer roll, 13: guide roll, 1
4: Hot-press roll, 15: Cooling roll, 16: Pull-out roll.

[Chemical formula 3]

Claims (1)

(57) [Claims] 1. A multilayer film comprising a mixed layer of a perfluorinated alkoxy layer, a perfluoroalkoxy powder and polyphenylene sulfide or polyether sulfone.