JPS6135227A - Folding guide of inflation film - Google Patents

Abstract

PURPOSE:To enable to fold the titled film at high rate without generating creases, sagging and fold, by a method wherein a space between openings is surrounded substantially by a circumferential wall and the circumferential wall is provided with a heating device heating bubbles passing through the circumferential wall. CONSTITUTION:As for a guide 11, the top of the same possesses a slitlike opening part 12 guiding bubbles 2 to an abutting part 5a of nip rolls 5 and the lower end of the same on a die side is provided with an opening part 13 in a circular or oval shape introducing the bubble 2. An intermediate part of a circumferential wall is of a shape of an ellips wherein a major axis of the same becomes long gradually in a lengthwise direction of the nip rolls 5 according as the intermediate part approaches the nip rolls 5. The guide 11 is fitted with a heater 17 heating the bubbles 2 from the room temperature and keeping using resin at an arbitrary temperature. When the bubbles 2 are passed through the guide 11 constituted in this manner and led to the nip rolls by keeping the guide 11 at the predetermined temperature by the heater 17, a flat film which does not have creases, sagging and fold can be obtained highly efficiently even in a high-tension modulus film.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a guide button for folding thermoplastic blown films.

Conventional technology Conventionally, using the inflation method from thermoplastic fat! 7 In order to fully mold the film, the raw resin is heated and melted and extruded through the annular slit of the die to form a bubble, while air is blown through a cooling ring to cool and crystallize it, as shown in Figure 4 (→
As shown in (1,), free rolls 1. ..., or as shown in Fig. 5, instead of the free roll 1, a guide such as a bar 4 made of iron, aluminum, etc., with wood or felt 3 etc. attached to the sliding surface of the bubble 2 to improve sliding, is used. It is guided to nip rolls 5 and folded, and then taken off by take-up rolls (not shown).

(ASTM, D882)
When folding a film made of BS& polyphenylene oxide (polycarbonate, etc.), wrinkles, sagging, and folds occur, making it difficult to obtain a flat film.In addition, with wider films, this tendency is exacerbated.
The folding speed must be extremely slowed down, resulting in an extremely low production capacity.

Purpose of the present invention In view of the above circumstances, the present invention provides a tensile modulus of elasticity of 1oooo
High-elastic modulus resin inflation films that cause folding can be folded at high speed and without wrinkling, sagging, folding, etc. even if these films have a fold diameter of 600 mm or more. The purpose of this invention is to provide a folding guide that can be used for folding.

The gist of the structure of the present invention is that it has a slit-like opening at one end and an opening for introducing bubbles at the other end, and a peripheral wall substantially surrounds the openings, and this peripheral wall has a An in-7 ratio/film folding guide is provided with heating means for heating passing bubbles.

Specific configuration of the present invention FIGS. 1 and 2 (a), (b), (o), (d), and (e) show one embodiment of the guide 11 according to the present invention.
viA is a perspective view, Fig. 2 (a) (b) (o) (d) (
e) is a plan view and a sectional view of respective parts of the guide 11. Guy, do l'1 is the upper end busy nip roll 5
The contact part 5 & slit-shaped opening [1
2, and is provided with a circular or oval opening 13e into which the lower end bubble 2 on the die side is introduced. These openings 12
The surrounding wall substantially surrounds the area between 130° and 130°. The middle part of the above-mentioned peripheral wall is shown in FIG.
As shown in the cross section at 15.16°, it is an ellipse whose long axis continues in the longitudinal direction of the nip roll and becomes gradually longer as it approaches the nip roll 5. A heater 17 is attached to the guide 11, which heats or keeps the resin used from room temperature to a desired temperature through the bubble 2 passing therethrough, as shown by the dashed line in FIG. The inner surface of the guide 11 is
In order to improve the sliding of the bubble and keep it warm, it is preferable to cover it with felt, for example. Although there may be some gaps in the peripheral wall, it is preferable to have no gaps in order to make the temperature uniform. The guide 1lt having the VC configuration as described above is maintained at a predetermined temperature by the heater 17 and the bubble 2 is heated. When the film is passed through and guided to the nip roll 5, a flat film without wrinkles, sag, or folds can be obtained with high efficiency even when a high tensile modulus film is used. It is also possible to provide a device for forming a gusset within the guide.

Note that the heater 17 is not particularly limited as long as it can heat and keep warm within a predetermined temperature distribution of the guide 1it.
Usually, a ribbon heater, a band heater, or the like is attached to the outer surface of the guide 11, or in some cases, it is used by disposing it between the guide and felt. Also, the heating temperature is set to a level that does not cause the film to stick or deform.

FIG. 3 shows another embodiment of the guide according to the present invention, in which heating means are not shown, but the peripheral wall has two flat plates 21 and 21, two triangular side plates 22 that close the sides, 2
2, and a heater (not shown) is attached to a flat plate 21 and a side plate 22. Bubble 2 is the bottom opening 1
3', it passes through the upper end slit-shaped opening 12' and is guided to the nip roll 5, and its performance is much superior to that of conventional buttons.

Examples 1 to 8 One lip gap in a 55-type air-cooled inflation molding machine: 2. ON1m, 300 dragon l dice installed,
Using the guide shown in Figure 1, which is made of galvanized iron and has IQH felt attached to the inner surface, the bubble is heated and insulated according to the type of resin, and blown film of various resins can be folded. I conducted a test.

Example 9 Air-cooled inflation molding of 55 silk A die of 8 VC lip gap 1.0111410 QHz was attached, and molding was carried out in the same manner as in Examples 1 to 8.

Similarly, I was busy conducting a folding test for a blown film of seed menarche oil.

Comparative Examples 9 to 12 A folding test was conducted on blown films made of various resins around the entire circumference of the guide shown in FIG. 5, in which a 7-elt was attached to an aluminum bar.

Results of Examples and Comparative Examples are shown in Table 1 (Part 1) and (Part 2)
As shown in .

Effects of the Present Invention As described above, the blown film folding guide according to the present invention can handle not only normal thermoplastic resin films but also high tensile modulus resin blown films such as engineering plastics without wrinkles, sagging, or This makes it possible to fold at high speed even a wide cicada with a folding diameter of 60 ON or more without causing folding.

[Brief explanation of drawings]

Figures 1 and 2 (a), (b), (a), (a) and (e) show an embodiment of the blown film folding guy P according to the present invention, and Figure 1 is a perspective view. , @2 Figures (a) and (b) are plan views of the openings at the upper and lower ends, Figure 2 (0)
(Ii) (s) is a cross-sectional view taken along the o-a arrow in FIG. A perspective view showing another embodiment, FIG.
aJ (b) shows a conventional guide using a free roll.
Fig. 5 is a view corresponding to Fig. 4 (b) of the guide using a felt adhesive bar instead of the 7 reel roll. 2...Bubble, 5...・Nip roll,
5a...Abutment part, 11...Guide, 1
2. Iz... Upper end slit-shaped opening, 13,1
3'...Lower end opening, 17...Heater. Figure 1 Figure 2 (C) (b) Figure 3 Figure 5PJ4 Figure 4 (b) n

Claims (1)

[Claims] having a slit-like opening at one end and an opening for introducing the bubble at the other end, a peripheral wall substantially surrounding the openings, and heating means for heating the bulb passing through the peripheral wall. A guide for folding inflation film.