JPS60203652A - Flame-retardant ultrathin film - Google Patents

Abstract

PURPOSE:To obtain the titled film of extremely high flame-retardancy and outstanding various physical properties, by incorporating linear high-density polyethylene with ethylenebis(tetrabromophthalimide) and/or bis(pentabromophenoxy) ethane and flame-retardant promotor. CONSTITUTION:The objective film can be obtained by incorporating (A) 100pts.wt. of linear polyethylene with a melt index 0.01-0.20g/10min and density 0.945-0.960g/ml with (B) 3-40 (pref. 5-20)pts.wt. of ethylenebis(tetrabromophthalimide) and/or bis(pentabromophenoxy)ethane and (C) 1-10pts.wt. of an antimony- and/or boron-based flame-retardant promotor.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flame-retardant ultra-thin film made of linear high-density polyethylene, and its object is to provide an ultra-thin film with extremely high flame retardancy.

Currently, in addition to the traditional balance of chemical and physical properties, there is a strong demand for safety against large flames, that is, flame retardancy, for flammable plastic products, including molded products made of linear high-density polyethylene. has been done. This situation is no exception for ultra-thin films, and depending on their flame retardance, they may be forced to withdraw from some of the previously developed demand fields, such as civil engineering and construction materials, electrical components, and industrial packaging materials. The situation is such that a situation may arise.

Although ultra-thin films are sometimes molded by T-die processing for special purposes, most of them are usually formed by inflation processing. The molding of ultrathin films of linear high-density polyethylene is carried out at 190°C to 26°C.
Processing conditions such as a resin temperature of 0℃, a film thickness of 30 micrometers or less, a large blowing ratio, and high-speed productivity of 60 to 100 m/min are required, which are extremely harsh compared to processing conditions for other polyolefin products. At the same time, the resulting ultra-thin film has physical properties unique to ultra-thin films, such as the absence of wrinkles and creases, film surface smoothness, thickness uniformity, film strength, and balance in the vertical and horizontal directions. requested. Naturally, flame retardance must be achieved while meeting these requirements. Conventionally, hundreds of kinds of flame retardants and flame retardant methods have been developed and proposed for making plastics flame retardant. However, as mentioned above, it is said that it is extremely difficult to make ultra-thin linear high-density polyethylene films flame retardant because strict processing conditions and unique film properties are required. That is, to make the film flame retardant, it is common to add a flame retardant and, if necessary, a flame retardant to the raw material linear high-density polyethylene, and then process the film.
In that case, the decomposition of the flame retardant during processing may generate corrosive gases, and the inability to form bubbles due to pinhole formation.
Various problems occur, such as destabilization of bubbles due to uneven thickness and decreased productivity due to fluctuations in the melt physical properties of the molten resin. Furthermore, the resulting film suffers from undesirable phenomena such as wrinkles, walnuts, coagulum, gel, and blooming of the flame retardant, and at the same time, the required strength balance is completely lacking.

As a result of intensive studies aimed at making ultra-thin films made of linear high-density polyethylene flame-retardant, the present inventors have found that among many flame retardants, flame-retardant methods, and flame-retardant compositions, the present invention has been found. The inventors discovered the unexpected fact that only the composition used as a raw material for the flame-retardant ultra-thin film of the invention enables the production of the flame-retardant film, and thus completed the present invention.

That is, in the present invention, the melt index is [101 to
[L209/10 minutes, density α945 ~ 0.96097
m1 of linear polyethylene, 3 to 30 parts by weight of ethylene bis(tetrabromo7talimide) and/or bis(pentabromophenoxy)ethane, an antimony-based flame retardant aid, and/or a boron-based flame retardant. This is a flame-retardant ultra-thin film containing 1 to 10 parts by weight of an auxiliary agent.

The linear polyethylene used in the present invention is JISK-
Melt index [MI] obtained according to 7210 is 0.01 to 0.209/10 minutes, density obtained according to JISK-7112 is 0.945 to 0°0.9609/m
It is a linear polyethylene that has basic physical properties of 1 and is produced by a medium-low pressure method.

Conventional ultra-thin films use the above-mentioned polyethylene and generally have the following processing conditions: Resin temperature = 190-230°C Blow ratio: 3 or more Full line height: 30-65 on Production speed:
60~100m/min Film thickness: 5~30μm Underneath, there is a rapid compression metering type screw with L/D of 24 or more and compression ratio of 2~4, and the capacity is 5.5 depending on the diameter. It is molded by the inflation method using an extruder with a main electric motor of ~40 KW. The film of the present invention can be applied and molded as is without changing the general manufacturing conditions described above.

Ethylene bis(tetrabromo heptatalimide) and/or bis(
Both pentabromophenoxy)ethane are used as halogen-based flame retardants, and currently have a resistance of 1! It is used to make iS polystyrene and ABS resin flame retardant, but
The fact that the flame retardant makes it possible to make ultrathin linear polyethylene films flame retardant in the specific formulation used in the present invention has not been known until now.

The amount of the halogen flame retardant necessary to obtain the effects of the present invention is as follows:
It is 5 to 30 parts by weight. Preferably it is 5 to 20 parts by weight. If it is less than 3 parts by weight, the flame retardance of the film will be low, and if it is more than 50 parts by weight, it will be difficult to mold the film, making it necessary to change the molding conditions.

Examples of antimony-based flame retardant aids used in the present invention include antimony trioxide, potassium antimonate, and diantimony tetroxide, and examples of boron-based flame retardant aids include zinc borate. can be mentioned. The amount of the flame retardant aid required to obtain the effects of the present invention is 1 to 10 parts by weight per 100 parts by weight of the linear polyethylene resin.

If it is less than 1 part by weight, the effect of addition as a flame retardant aid is small;
If the amount is more than 10 parts by weight, not only can no significant increase in the effect of addition be expected, but it also becomes difficult to form the film.

The flame retardant ultra-thin film of the present invention has no wrinkles or walnuts,
The surface is as smooth as a film not containing the flame retardant, and no blooming of the flame retardant or flame retardant aid is observed. Furthermore, there are no lumps (coagulates) caused by the flame retardant or flame retardant aid in the film, and the additives are well dispersed. Such film properties meet market requirements and are desirable for effective development of flame retardancy.

Generally, ultra-thin films are often used by subjecting their surfaces to plasma treatment or corona discharge treatment and then printing or coating them by printing or aluminum vapor deposition. There are no problems with printability or aluminum vapor deposition after surface treatment, and printing or aluminum vapor deposition is possible using conventional methods and operations.

The method for mixing the ingredients of the flame retardant ultra-thin film of the present invention is as follows:
Known methods commonly used when adding and blending other organic or inorganic substances to plastics can be used as is. For example, a mixing method using a master batch method can be mentioned.

This is the simplest method, but of course a method of direct mixing may also be used.

In addition, additives that are generally added to linear polyethylene for raw materials or polyethylene for masterbatch production,
For example, antioxidants and ultraviolet absorbers.

There is no problem in containing a slip agent or the like, or adding them as appropriate.

The flame-retardant ultra-thin film of the present invention is made by blending specific flame retardants and flame-retardant aids with linear high-density polyethylene. This film was able to overcome difficult processing conditions and satisfy the physical properties required for conventional ultra-thin films, while also adding flame retardancy.

In other words, flame retardants, etc. can be decomposed during processing without changing the conventional processing conditions for ultra-thin films.

Not only can the flame-retardant ultra-thin film of the present invention be easily produced without problems such as pinhole generation and bubble instability, but the obtained flame-retardant ultra-thin film of the present invention has no wrinkles or walnuts. It is free from defects such as coagulation and blooming, maintains good film strength and balance, and has extremely high flame retardancy. Even if the flammable ultra-thin film of the present invention is ignited, it does not continue to burn and immediately extinguishes the flame.In this respect, safety against flames is ensured, so it can be widely used in fields that require this. can.

The present invention will be explained in more detail with reference to Examples below.
The present invention is not limited to these examples.

Example 1 40 m/m high-speed twin-shaft continuous kneading machine (N manufactured by Kobe Steel)
Pellets of the highly concentrated composition (masterbatch) shown below were produced at a resin temperature of 200°C.

Next, linear polyethylene pellets (Niboron hardener 730 pieces manufactured by Toyo Soda Kogyo ■, M engineering = O, OS, density = α
951) to 100 parts by weight of the masterbatch.
0 parts by weight was added and pellet mixing was performed using a ribbon blender. The mixed pellets were processed using an extruder (LM50 manufactured by Placo ■) under the following processing conditions: Resin temperature = 200°C Blow ratio: 6.4 Frost line height: 45 cm Production speed: 60 m/min Film thickness = Film molding was performed by the inflation method under IQpnt. The obtained film was free of wrinkles and curvature, had a smooth surface, and had no lumps (coagulation) or blooming caused by the flame retardant or flame retardant aid. As shown in Table 1, the film had excellent flame retardancy while maintaining good film strength and balance.

Example 2 Ethylene bis(tetrabromophthalimide) of Example 1
A film was produced using the same recipe, procedure 1, and inflation processing conditions as in Example 1, except that bis(pentabromphenoxy)ethane (Pyrocheck 77B, manufactured by 7EP Corporation) was used instead of. The resulting film had an excellent film appearance similar to the film of Example 1. As shown in Table 1, the film properties such as film strength, film strength balance, and flame retardance were all good.

Example 6 The masterbatch of Example 1 was mixed with 10 weight j1 (2 parts).
A film was produced using the same recipe, nine operating procedures, and inflation processing conditions as in Example 1, except that the amount was increased to 0 parts by weight. The bubble stability during manufacturing was good, and the molding process was smooth. Film appearance, film g
As shown in Table 1, the results were extremely good.

Example 4 Linear polyethylene pellets used in Example 1 and Example 2
The halogen-based flame retardant and antimony trioxide used in the above were weighed so that the weight composition ratio was approximately 100:20. The polyethylene pellets were melted on a Shimada roll (manufactured by Nishimura Koki Co., Ltd.) with a roll diameter of 16 inches and a roll temperature of 170±5°C, and then the flame retardant and flame retardant aid were kneaded into the molten polymer. I took it out with a thick sheet. The sheet was pelletized using a pelletizer. Using this pellet, film molding was performed using the same processing machine and the same processing conditions as in Example 1. The stability of the bubble during production was good, and molding was possible without any problems. The appearance of the obtained film was extremely good, and as shown in Table 1, the balance of the two film strengths, flame retardance, etc. were all excellent.

Comparative Example 1 A film was prepared using the same materials, operation 1 procedure, and processing conditions as in Example 4, except that the weight composition ratio of linear polyethylene, halogen a flame retardant, and flame retardant aid was 100:40713, respectively. I did the molding. The stability of the bubble during processing was poor, and the molding process did not go well.

Comparative Example 2 Decabromodiphenyl ether (manufactured by Toyo Soda Kogyo ■, Flameka) BR was used instead of the halogen flame retardant of Example 1.
All formulations were the same as in Example 1, except for using
Film molding was carried out using 2 procedures and processing conditions. Although molding processability was slightly inferior to Examples 1 to 4, film processing was possible. However, blooming of the flame retardant was observed on the surface of the film.

Comparative Example 6 Chlorine flame retardant (7
Manufactured by Tsuriki Chemical Co., Ltd., Dechlorane Plus 25.20)
The same recipe and operation 1 as in Example 1 were used except that
The film was molded according to the procedure and processing conditions. The flame retardancy of the obtained film was extremely low.

Comparative Example 4 A film was formed using the same recipe, nine operating procedures, and processing conditions as in Example 1, except that tetrabromobisphenol A (manufactured by GLO) was used instead of the halogenated flame retardant in Example 1. went. The flame retardant is commonly used as a flame retardant for ABS resins and epoxy resins. The flame retardant decomposed during molding, making molding impossible.

Table 1 Evaluation method 1, Elmendorf tear strength IX8 Z 1702.
P81162, Film Impact A8TM D 7
814, flame retardancy MV88 method comparative example 5 Using chlorinated paraffin, which is often used to make molded products and films of low-density polyethylene and ethylene/vinyl acetate copolymer flame retardant, the flame retardance of ultra-thin linear polyethylene films was improved. I tried burning it. Using the kneader of Example 1, the resin temperature was 170.
Masterbatch pellets having the composition shown below were produced at .

Thereafter, a film was formed using the same recipe, procedure 1, and processing conditions as in Example 1.

The flame retardant decomposed during molding, making molding completely impossible.

Patent Applicant: Toyo Soda Kogyo Co., Ltd. Procedure: Written amendment (method) % formula % 1 Display of the case 1982 Patent Application No. 59477 2 Name of the invention Flame retardant ultra-thin film filtration Person performing the correction Telephone number (585) 3 11 4. Date of amended old order A. 6. Detailed explanation of the invention in the specification subject to amendment 7. Contents of amendment (1) Table 1 on page 15 of the specification shall be as attached (no change in content) ).

Claims (1)

[Claims] (1) Melt index is 0.01~a, zo9/
10 minutes, to 100 parts by weight of linear polyethylene having a density of 0.945 to 0.9609/rrtl, (a) ethylene bis(tetrablemore atalimide) and/or bis(pentabromophenoxy)ethane 6 A flame retardant ultra-thin film comprising: ~30 parts by weight and (b) 1 to 10 parts by weight of an antimony-based flame retardant aid and/or a boron-based flame retardant aid.