JPS6369852A - Polyethylene based resin composition - Google Patents

Abstract

PURPOSE:The titled composition, obtained by blending an ethylenic copolymer or terpolymer having polar groups with polyethylene and having improved film adhesive property of ink without impairing mechanical characteristics. CONSTITUTION:A composition obtained by blending (A) 100pts.wt. high-density polyethylene having >=0.94 density with (B) 1-30pts.wt., preferably 1-10pts.wt. ethylenic copolymer or terpolymer having polar groups and further (C) 0.05-2 pts.wt., preferably 0.1-1pt.wt. monoglyceride based antistatic agent expressed by the formula (Rn is alkyl; n is 11-20).

Description

Detailed Description of the Invention <Industry> Second Field of Application The present invention provides a resin composition with excellent physical properties and excellent coating film adhesion of printing ink. The present invention relates to a resin composition in which a 1-dylene copolymer or terpolymer having the following properties is added in a fixed proportion, and a resin composition in which a specific antistatic agent is added in a fixed proportion.

<Prior art> Like polypropylene resin, high-density polyethylene resin is a resin with excellent chemical resistance, mechanical properties, etc., and is also inexpensive, so it is widely used as a molding material 1.1. One of the disadvantages is that it does not contain polar groups or reactive active groups in its molecular structure, and it also has poor solubility in solvents, so it is difficult to handle secondary additions such as printing. It contains a lot of resin.

Therefore, in order to improve the coating adhesion of printing ink, it is necessary to treat the surface of the high-density polyethylene molded product to increase its affinity for ink 41I.

Specific surface treatment methods include ultraviolet rays, corona discharge,
There are methods of increasing surface affinity using plasma discharge, oxygen, and Z-pusin, and methods of roughening the surface using Sand Plus 1 and the like. Among these, surface activation using corona discharge treatment is common.

] Lob discharge treatment is defined as a phenomenon in which dielectric breakdown occurs in a part of a conductor to which a high voltage is applied in the air, where there is a large potential difference near the surface, and a discharge continues, but corona discharge treatment also causes ↓ It is not clear how the material surface changes. There is a physical view that the discharge creates fine irregularities and roughens the surface, and a chemical view that the surface is oxidized, improving affinity.Currently, however, chemical changes are The prevailing view is that oxidation or ionization activates the base material surface.

However, the problem that often arises with zero discharge treatment is that the durability of the surface activity is not sufficient due to changes in the surface treatment effect over time, and there are also limitations on the inks that can be used. There are drawbacks. Especially Offsela! For ultraviolet curable inks used for printing, etc., surface treatment by corona discharge treatment alone is insufficient to prevent ink film adhesion.
It was not enough to make the surface durable, so the surface was treated and then painted over. In addition, antistatic agents are essential to prevent process failures due to suction repulsion and dust absorption due to the generation of static electricity during subsequent processing and secondary processing. Fatty acid glycerides and the like are used. Generally, amine type agents are said to have quick-acting properties, while fatty acid glyceride type agents are said to have long-lasting effects, and are added in an appropriate ratio depending on the required performance.

The amount added is the minimum amount necessary to provide antistatic properties, but due to compatibility with olefins, antistatic agents are added]・Printability deteriorates over time due to the bloom phenomenon that appears on the surface. The problem was that it was declining.

<Purpose of the Invention> As a result of testing a method for improving the coating film adhesion of ink without impairing the mechanical properties of high-density polyethylene, the present invention has developed an ethylene-based material that adds polar groups to high-density polyethylene. - By adding polymer-b or terpolymer, without undercoating, only by corona discharge treatment,
The present invention was completed by discovering the fact that the adhesion between high-density polyethylene and ink is improved.

Furthermore, the second invention is based on the discovery of an antistatic agent that does not reduce printability over time in a = 5- formulation of high-density polyethylene and an ethylene type copolymer or terpolymer ( It is complete.

<Constitution> The present invention is made by adding 1 part by weight of one or more types of ethylene copolymer or terpolymer to 100 parts by weight of high-density polyethylene resin. Resin compositions, as well as specific antistatic agents,
The object of the present invention is to provide high-density polyethylene with improved printability by adding 0.05 to 2.0 parts by weight.

The high-density polyethylene resin used in the present invention is polyethylene obtained by polymerizing metal oxides, alkyl aluminum, etc. as catalysts under normal pressure or pressure, and has a density of 0.94.
It is 0 or more.

Ethylene-type copolymers or terpolymers having polar groups can be blended with high-density polyethylene resin, and monomers that can be polymerized with ethylene include vinyl acetate, acrylic acid, methacrylic acid,
Methyl acrylate, methacrylate, maleic anhydride.

chlorine, carbon oxide, etc., such as EVA, EAA,
It is a ternary combination of CPE snow copolymer, ethylene-acrylic f, hr-deru-maleic anhydride, J-blen-acid-resistant hyaluronic acid-carbon oxide, etc.

The effect can be seen when the amount added is one hanging part or more.

If a large amount is added, the tear force of Sea 1~ will become more directional, and if it exceeds 30 parts by weight, a significant decrease in tear force will be observed. If a smooth texture is required, 1 to 10 parts by weight is preferred.

Further, the antistatic agent used in the present invention has the following general formula (a)
It is a monoglyceride represented by

(a) 0 C112(]CRn Cl0II Rn-alkyl group C former OHn=1l-20 Regarding the number of carbon atoms in the alkyl group, below CIO, ink transferability is uneven, and above C20, static The electric protection cf- property and ink adhesion are reduced.When processability is taken into consideration, Cps to Cps is preferable.

Regarding the amount added, if the amount added exceeds 2.0 parts by weight, a decrease in ink adhesion is observed, and if the amount added is less than 0.05 parts by weight, the antistatic property is insufficient, and if the amount added is less than 0.1 ~1.
0 offer section is preferred.

The thus obtained resin composition is melt-extruded using an extruder equipped with a T-shaped die, and the surface of the obtained sheet is suitably powdered with polar groups of an ethylene copolymer or a 1-Uter polymer. A more uniform and highly active surface can be obtained by performing an activation treatment on m-+. As the activation process, the above process is appropriate.
Regarding the degree of treatment, it is desirable that the wetting surface tension is 44 to 54 dyn/c11 according to the method of JIS K-6768.

The surfaces of Sea 1 obtained in this way are sufficiently activated and can be adhered with ultraviolet curable ink.

<Function> Although there are 41 unknown points regarding the mechanism of adhesion, copolymers or terpolymers containing polar groups blended into the high-density polyethylene resin are dispersed on the surface in an appropriate manner, and compared to the normal resin composition. Even when corona treatment is applied to an object, the surface remains in an activated state, and regarding changes in the treatment effect over time, oxygen atoms on the surface of high-density polyethylene when subjected to lob treatment When considering the bonding state (oxidation) of , it can be considered that: 1) it bonds to a carbon atom to form a carbonyl group or a carboxyl group; 2) it adsorbs oxygen molecules; 2) it adsorbs ozone. It is known that the ratio of oxygen atoms on the sheet surface decreases with the passage of time, and it is unlikely that oxygen atoms in carbonyls and carboxyls that have primary bonds with carbon atoms will easily separate. Since I can't do it, M
It is thought that the activity decreases according to the osin #l theory.

By adding the ethylene-based copolymer or terpolymer having a polar group of the present invention to high-density polyethylene resin, the number of oxygen atoms that cannot be separated is larger than that of a resin composition without the addition. It seems that the effect decreases little over time.

In addition, regarding the blooming of antistatic agents, the polar groups of the polymers and terpolymers woven into the high-density polyethylene resin ensure that the antistatic agents are uniformly dispersed within the sheet for a long period of time, and the surface This seems to be because it is difficult for a rip-off layer to form.

<Examples> Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Examples (1) to (5), Comparative Examples (1') to (4') High-density polyethylene (density 0.965 Meltintedex 60, trade name Sumirikisenhard 2123, manufactured by Sumitomo Chemical) was coated with EVA-based coat. The polymer was added in the ratio shown in Table 1, an appropriate amount of monoglyceride antistatic agent was added, and the blend was melt-extruded using an extruder equipped with a 40 m/mφ T-type die, and the surface was subjected to corona treatment to Sea 1. , Sheet 1 non-pull was prepared, and an R1 tester was used to spread an ultraviolet curable ink on the obtained sheet sample, and the sample was irradiated with ultraviolet rays.

Table 1 shows the results regarding the adhesion between Sea 1 and Rimple and the ink and the tearing force of the sheet.

Examples (6) to (24), Comparative Examples (5') to (14'
) In place of the FvA copolymer in Table 1, various ethylene copolymers or terpolymers shown in Table 2 were added and the same operations as in Example 1 were carried out to prepare Sheet 1, and the ink was spread.

Is the unity shown in Table-2? J' Examples (25) to (30), Comparative Examples (15') to (1
7') Instead of the EVA copolymer in Example 1, two or more of the various dylene copolymers shown in Table 3 were added, the same operations as Example 1 were performed to create a sheet, and the ink was spread. did.

The results are shown in Table-3.

Examples (31) to (40), Comparative Examples (18') to (2)
6') High-density polyethylene (Sumiyuki Senhard 272
3), EVA copolymer (Sumitomo Chemical!! IH-4
The monoglyceride antistatic agent shown in Table 4 was added to the resin composition containing 011>10 parts by weight. The same operations as in Example 1 were carried out to prepare sheets 1 to 1, and the ink was spread, and the surface resistivity of each sample was also measured.

The results are shown in Table-4.

<Effect> Table 11 Table 22 Table 3. As is clear from the above, the first invention is a polyethylene resin in which 1 to 30 parts by weight of one or two or more ethylene copolymers or terpolymers are added to 100 parts by weight of a high-density polyethylene resin. When the resin composition is molded into a C-i~ color and developed, the ink adhesion is good (lr), and the desired effect can be achieved by 1q without reducing the tear resistance.

From Table 4, it can be seen that the composition of the first invention, which is the second invention, with the monoglyceride antistatic agent added to the car number part of 05-2.0 and molded into sheets 1 to 1 has the color spreadability of the ink, It can be seen that the adhesion was good in all dimensions, and that the desired effect with high practicality could be obtained.

Note 1 EVA type, Sumima Kagaku) (-4011 mel 1 hein index 20, density 0.940, vinyl acetate 20%) Note 2 EHHA type, Sumima Kagaku - A-1703 melt index 7.0, density 0.930, methyl methacrylic acid 10% 3 1EAA type Mitsubishi Yuka A-22M melt index 7.0 Density 0.940 Acrylic acid amount 8.5% Note 4 [FA type Mitsui DuPont Chemical A-702 Melt index 50 Density 0.930 Acrylic acid 19% 715CPE Model Showa Denko 403A Melt index 36 Density 1.20 Chlorine 40% Note 6 E) To IΔ8 New Year DuPont Chemical 1027
C melt index 7.0 Density 0.940 Methacrylic acid 12% Note 7 Ethylene-Ethyl acrylate-Maleic anhydride Sumitomo Chemical AX-8040 Density 0.930 Acrylic acid-Maleic anhydride 32% Note 8 Ethylene-Vinyl acetate-Oxidation To test the adhesion of carbon Mitsui Dekopon Chemical Elvaloy 742 Melt Index 35 ink, make a 2+wm square goblin on the printed surface and place it in close contact with Rerohantabe (made by Chiban ■).
A sudden rip-off operation was performed in the 45° direction, and the ink was peeled off. The adhesion of the ink (■) is normal, and the adhesion (2) of the printing ink is the one obtained by printing after the sheets 1 to 1 were left at 50° C. for 48 hours. Tear force is JIS K-677
2.

Surface resistivity was measured according to ASTM D-257.

O...No abnormality △・・・Slight peeling ×・・・Significant peeling

Claims (2)

[Claims] (1) For 100 parts by weight of high-density polyethylene resin,
A polyethylene resin composition with improved printability, which contains 1 to 30 parts by weight of one or more ethylene copolymers or terpolymers having polar groups. (2) For 100 parts by weight of high-density polyethylene resin,
Blend 10 containing 1 to 30 parts by weight of one or more ethylene copolymers or terpolymers
0.05 to 0.05 parts by weight of one or more monoglyceride antistatic agents represented by the following general formula (a).
2.0 parts by weight of a polyethylene resin composition with improved printability. (a) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Rn = alkyl group n = 11-20