JPS5939456B2 - Method for forming a cloudy pattern on the surface of a polyethylene terephthalate resin bottle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a cloudy pattern on the surface of a polyethylene terephthalate resin.

The purpose of this invention is to add interest to the appearance of a transparent polyethylene terephthalate resin by forming a cloudy part in a film shape on the surface of the polyethylene terephthalate resin in a desired form by utilizing the thermal properties of the polyethylene terephthalate resin. This is what I did.
When drawing a pattern on the surface of a synthetic resin material, unless the pattern is an uneven pattern, use an ink or sheet material that is completely separate from the synthetic resin material that forms the material, such as printing or transfer. This was achieved by attaching it.

In this way, the pattern on the surface of the conventional synthetic resin bottle is formed by attaching a material completely different from that of the main body of the bottle, so it requires complicated equipment to form the pattern and requires the use of other materials. There were drawbacks such as the pattern peeling off due to contact with other objects.

In particular, when forming patterns by printing, it takes a certain amount of time for the printed ink to dry completely, so it takes a long time to complete one increase, which significantly reduces work efficiency. was. In addition, as a recent trend, the patterns on increased salaries are not bright primary colors, but rather
There is a tendency for neutral colors and cloudy white colors that have a blurred appearance to be sought after because they can give a deep and calm appearance. Particularly, when a cloudy pattern is formed on the surface of a bulge molded from a transparent synthetic resin material, this pattern is given a three-dimensional effect and a deeper appearance can be obtained.

However, due to the structure of the printing screen, it has been extremely difficult to obtain this neutral color, blurred feeling, and especially translucent white cloudiness by printing ink on the surface of the ink, and requires troublesome operations. The present invention addresses the various problems and drawbacks of the conventional polyethylene terephthalate resin surface, which has recently begun to be widely used and has excellent properties such as mechanical strength, content resistance, non-pollution, and transparency. This method was devised to form a cloudy pattern without causing any turbidity, and is a method that utilizes the thermal properties of polyethylene terephthalate resin to form a cloudy pattern on the surface of the wire by simply heat-treating it.

Embodiments of the present invention will be described below with reference to the drawings.

As is well known, polyethylene terephthalate resin has a
Polyethylene terephthalate resin has a thermal property that cloudiness occurs when it is slowly cooled in the temperature range above [℃], especially around 140[℃], but due to this thermal property, molding of polyethylene terephthalate resin is technically difficult. This has become one of the most serious drawbacks of polyethylene terephthalate resin.
The basic idea of the present invention is to make the surface 2 of the polyethylene phthalate resin bottle 1 cloudy by utilizing the thermal properties of the polyethylene terephthalate resin, which were conventionally considered to be disadvantageous.

That is, the desired portion 2a of the surface 2 of the bottle 1 to be made cloudy
is rapidly heated locally (not to the inside of the wall of bottle 1, but only to a limited surface area) to a predetermined temperature in the range of 100 [°C] to 300 [°C], and then this rapidly heated By slowly cooling the portion 2a by leaving it in the atmosphere, etc., only the portion 2a becomes cloudy.

In this case, only the part 2a becomes cloudy, that is, the surface 2
Since the inside of the wall that constitutes the bottle body 1 is not clouded by only a part of it, this cloudiness is formed in a translucent state.

Further, since the heating operation for making the portion 2a cloudy acts only on the portion 2a and not on other portions, there is no risk of any inconvenience such as deformation of the bottle 1 due to heat.

Incidentally, the cloudiness on the surface 2 formed in this way is not caused by printing or transfer, but is caused by a change in the physical properties of the polyethylene derephthalate resin itself that forms the bottle body 1, so the cloudiness is caused by a change in the physical properties of the polyethylene derephthalate resin itself, which is used to mold the bottle body 1. The degree of printing becomes uniform, and there is no risk of problems such as peeling or bleeding that occur in conventional printing. The method of forming a cloudy pattern on the surface of a polyethylene terephthalate resin bottle according to the present invention is based on the above-mentioned basic idea. The bottle body 1 is relatively rotated while being brought into pressure contact without slipping on the surface 4 of the heating body 3, which is provided with a desired number of pattern protrusions 4a with a desired flat surface shape on the protruding end surface. After rapidly heating the portion 2a of the surface 2 that is moved and comes into contact with the protruding end surface of the pattern protrusion 4a to a temperature in the range of 100 [° C.] to 300 [° C.], this portion 2a is slowly cooled to make it cloudy. This is what I did.

In the illustrated embodiment, the heating body 3 is in the form of a roll;
A large number of patterned protrusions 4a are protruded from the surface (peripheral surface portion) 4 of the heating body 3, and each of which has a desired end face shape (square in the illustrated embodiment).

It goes without saying that the protruding heights of the pattern protrusions 4a are all the same, and the protruding tip surfaces of all the pattern protrusions 4a are located on the same imaginary cylindrical surface whose axis coincides with the axis of the heating body 3.

The bottle 1 is arranged with respect to the heating body 3 so that its axis is parallel to the axis of the heating body 3 in the same direction.
While pressing the bottle 1 and the heating body 3 with a desired pressing force, the bottle 1 and the heating body 3 are rotated relative to each other in such a manner that no slipping occurs between the contact surfaces.

At this time, it is obvious that only the pattern protrusions 4a on the surface of the heating element 3 come into contact with the surface 2 of the bottle 1, and the remaining portion 4b cannot come into contact with the surface 2 of the bottle 1. Since the contact state between the heating body 3 having the pattern protrusions 4a and the surface 2 of the bottle body 1 is as described above, the surface 4 of the heating body 3 is now heated from 100[°C] to 30°C.
When heated to a predetermined temperature in the range up to 0°C, the surface 4 of the surface 2 of the bottle 1 facing the surface 4 of the heating element 3
Only the portion 2a that directly contacts the pattern protrusion 4a, that is, the portion 2a facing the pattern protrusion 4a, is locally heated from 100 [°C] to 300 [°C].
It will be heated to a predetermined temperature in the range up to . In this way, when the bottle 1 is pressed against the heating body 3 provided with a large number of pattern protrusions 4a and rotated once without slipping, the surface 2 of the bottle 1
Of these, only the portion 2a facing the pattern protrusion 4a is 100
It is heated to a temperature in the range from [° C.] to 300 [° C.], and therefore, by slowly cooling this portion 2a, the portion 2a becomes cloudy.

That is, the cloudy pattern set by the pattern protrusions 4a is formed on the surface 2 of the bottle 1.

Incidentally, in the case of the illustrated embodiment, the heating body 3 has a roll structure, but the heating body 3 is not limited to the roll structure and may have a flat plate shape. However, considering the ease of forming the cloudy pattern and the simplification of the structure of the apparatus for carrying out the method of the present invention, it is considered advantageous for the heating body 3 to have a roll structure. Furthermore, it goes without saying that the surface portion or the entire heating body 3 may be molded from a heat-resistant elastic material such as silicone rubber.

This is because the entire area of the protruding tip surface of the pattern protrusion 4a can come into contact with the surface portion 2a evenly and reliably.

As is clear from the above explanation, the cloudy white pattern formed according to the present invention is not caused by ink printing or transfer, but is formed by a change in the physical properties of the polyethylene terephthalate resin itself located on the surface of the bottle. Because it is made of solid wood, there is no risk of peeling or smearing, and the degree of cloudiness is uniform and the shape can be set freely.
In addition, since the cloudy material according to the present invention is translucent, it gives the pattern sufficient depth and three-dimensionality, making the appearance of the bottle body 1 desirable, and the molding method is far more convenient than conventional printing and transfer methods. It has many excellent effects, such as being simple and easy to operate and implement with equipment.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is an overall perspective view showing an embodiment of a cloudy pattern forming method according to the present invention using a heating body having pattern projections on its surface;
FIG. 2 is an enlarged vertical cross-sectional view of a main part showing the contact state between the heating body and the bottle shown in FIG. 1, and FIG. 3 shows the method of the present invention shown in FIG. 1. FIG. 2 is an overall perspective view of a bottle with a cloudy pattern formed thereon. Explanation of symbols, 1; Bottle, 2; Surface, 2a, 2b: Part;
3: heating body, 4: surface, 4a: pattern projection, 4b: part.

Claims (1)

[Scope of Claims] 1. The bottle 1 is relatively rotated and moved while being in pressure contact without slipping on the surface 4 of the heating body 3, which is provided with a desired number of pattern protrusions 4a with a desired flat surface shape on the protruding end surface. The portion 2a of the surface 2 that contacts the protruding end surface of the pattern protrusion 4a is 100.
A method for forming a cloudy pattern on the surface of a polyethylene terephthalate resin bottle by rapidly heating the portion 2a to a temperature in the range from [°C] to 300 [°C] and then slowly cooling the portion 2a.