CN115636297A - Slitting method of BOPP film - Google Patents

Abstract

The invention discloses a cutting method of a BOPP film. The invention adopts higher tension and pressure in the initial stage to prevent the generation of white marks due to sliding; the condition that the speed is increased due to the change of the speed is avoided, so that the end face of a film roll is uneven and scratched due to the jumping of a roller; when the winding is about to be completed, the running speed of the splitting machine is kept in a high-speed state to prevent more scratches; the aluminum-plated base film which has high brightness, good barrier property and good adhesive force is obtained by the scheme, and the advanced level in China is reached. The prepared aluminized base film can meet the equipment change of downstream customers, meets the market demand and saves the cost of the customers.

Description

Slitting method of BOPP film

Technical Field

The invention relates to the technical field of high polymer materials, in particular to a slitting method of a BOPP film.

Background

At present, the widely applied aluminized label films on the market mainly comprise a CPP aluminized film and a BOPE aluminized film, wherein the CPP aluminized film has the defects of low stiffness, the BOPE aluminized film is only suitable for the environment of 90 ℃, and the BOPP aluminized film can keep certain stiffness and can also be used in the environment of higher temperature. And because the polyester aluminizer has certain defects in surface smoothness and smoothness, the adhesion of the aluminizer and the finally presented brightness cannot be ensured to achieve the ideal effect at the same time. Moreover, due to the update of downstream customer equipment, the aluminum-plated basement membrane with the specification of 2030 is required, but the aluminum-plated basement membrane is not available on the market and cannot meet the market demand.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the method for slitting the BOPP film is provided, and the aluminized base film with high brightness, good barrier property and good adhesive force is obtained, so that the defects of the prior art are overcome.

The invention is realized by the following steps: a BOPP film slitting method, in the initial stage, the inboard tension is 184-380N, the outboard tension is 184-380N, the inboard pressure is 140-450N, the outboard pressure is adjusted to 140-450N; setting the initial tension to be 0.065-0.085N/mm, setting the tension to be 0.020-0.040N/mm correspondingly at the speed, setting the initial contact force to be 0.016-0.320N/mm, setting the unreeling tension to be 0.070-0.080N/mm, setting the starting speed to be 90-110m/min, and then manually and gradually increasing at the speed of 15-25 m/min; when the winding is about to be finished, the running speed of the splitting machine is kept between 350 and 450m/min.

The size of the BOPP film is larger than 2000mm, and the thickness of the BOPP film is larger than 50 micrometers.

The invention optimizes each cutting parameter, and correspondingly, the selected cutting blade needs to be replaced by a quality blade which is matched with each parameter and has higher hardness and better wear resistance; the compression roller needs to be replaced by a roller with moderate hardness, upward bias and no bottom texture; arranging and cutting specifications according to the requirements of a planning sheet, selecting a paper tube with thickened tube core, high roundness, polished tube surface and high flatness, moving the paper tube to a specified position, neatly placing the paper tube, and sticking a double-sided adhesive tape for later use.

Before the splitting machine is started, whether the air pipes are inserted in pairs or not is checked, and the connection mode of the winding arm and the air cylinder is changed into parallel connection; after the splitting machine is started, the tightness of the film roll is analyzed, the film roll cannot be too loose and too tight, the loose core can be caused by the too loose, and the too tight stripe can be generated.

In the traditional process, because the slitting parameters are difficult to adjust and the selection of blades, compression rollers and paper tubes is difficult, the slitting machine cannot slit BOPP films with the width larger than 2000mm and the thickness larger than 50 micrometers, a large number of BOPP films with the width larger than 2000mm and the thickness larger than 50 micrometers, which are urgently needed by market client equipment, are successfully slit and obtained through the setting value and equipment adjustment of the slitting parameters, and the problems that white marks, uneven end faces of film rolls and scratches are generated when 2000mm is slit in the prior art are solved. And the obtained aluminized base film has the same performance as that of an aluminized base film with other small specifications (such as 940, 1820 and the like) in cutting, namely high brightness, good barrier property, good flatness and good adhesive force.

Due to the adoption of the technical scheme, compared with the prior art, the invention adopts higher tension and pressure in the initial stage so as to prevent the slide from generating white marks; the condition that the speed is increased due to the change of the speed is avoided, so that the end face of a film roll is uneven and scratched due to the jumping of a roller; when the winding is about to be finished, the running speed of the splitting machine is kept in a high-speed state so as to prevent more scratches; the aluminum-plated base film which has high brightness, good barrier property and good adhesive force is obtained by the scheme, and the advanced level in China is reached. The manufactured aluminized base film can meet the equipment change of downstream customers, meets the market demand and saves the cost of the customers.

Detailed Description

Example 1: a BOPP film slitting method, in the initial stage, the inboard tension is 184-380N, the outboard tension is 184-380N, the inboard pressure is 140-450N, the outboard pressure is adjusted to 140-450N; setting the initial tension to be 0.065-0.085N/mm, setting the tension to be 0.020-0.040N/mm correspondingly at the speed, setting the initial contact force to be 0.016-0.320N/mm, setting the unreeling tension to be 0.070-0.080N/mm, setting the starting speed to be 90-110m/min, and then manually and gradually increasing at the speed of 15-25 m/min; when the winding is about to be finished, the running speed of the splitting machine is kept between 350 and 450m/min.

The size of the BOPP film is larger than 2000mm, and the thickness of the BOPP film is larger than 50 micrometers.

Example 2:

the relevant experimental data for the product of each example need to be provided as a corroboration.

The finished product obtained after cutting in example 1-3 was subjected to membrane surface quality analysis, and the results obtained were as follows:

TABLE 1 film surface quality at different slitting parameters

As can be seen from Table 1: the invention effectively improves the quality of the film surface in the slitting process by improving the equipment and adjusting the process parameters.

The analysis of the embodiment 1 shows that the abrasion can be effectively reduced by changing the connection mode of the air cylinders into parallel connection, replacing the blades with the blades made of special materials, replacing the paper tubes with thickened paper tubes, and turning the large film roll for 180 degrees before slitting;

the analysis of the embodiments 1 and 2 shows that the flatness of the end face can be effectively improved by reducing the increment delta v of the splitting machine when the speed is increased each time;

the analysis of the examples 2 and 3 shows that the problem of film surface scratch during the slitting of the wide film can be further improved by increasing the tension and the pressure of the inner side and the outer side;

the analysis of the embodiment 1-3 shows that the main source of the white print is the press roll shading, and the problem of the white print can be effectively improved by replacing the wide film with the press roll without the shading because the wide film has larger tension and pressure during slitting compared with the common product.

Claims (2)

1. A cutting method of a BOPP film is characterized in that: in the initial stage, the inner side tension is 184-380N, the outer side tension is 184-380N, the inner side pressure is 140-450N, and the outer side pressure is adjusted to 140-450N; setting the initial tension to be 0.065-0.085N/mm, setting the tension to be 0.020-0.040N/mm correspondingly at the speed, setting the initial contact force to be 0.016-0.320N/mm, setting the unreeling tension to be 0.070-0.080N/mm, setting the starting speed to be 90-110m/min, and then manually and gradually increasing at the speed of 15-25 m/min; when the winding is about to be completed, the running speed of the splitting machine is kept between 350 and 450m/min.

2. The slitting method of a BOPP film according to claim 1, wherein: the size of the BOPP film is larger than 2000mm, and the thickness of the BOPP film is larger than 50 micrometers.