JPS60163949A - Polypropylene composition - Google Patents

Abstract

PURPOSE:To provide a polypropylene compsn. suitable for use in press-through package and having excellent transparency, thermoformability and safety, by incorporating a specified petroleum resin in a polypropylene resin. CONSTITUTION:A hydrogenated petroleum resin having a softening point of 124 deg.C or above is added to 100pts.wt. polypropylene. The quantity of the petroleum resin varies depending on the softening point, but is usually 3-20pts.wt., pref. 6-11pts.wt. per 100pts.wt. polypropylene. When the quantity is less than 3pts.wt., no satisfactory effect of improving transparency and thermoformability can be obtd., while when it exceeds 20pts.wt., thermoformability is deteriorated. Examples of the polypropylene resins are homopolymers and random copolymers of propylene with alpha-olefins, among which copolymers having a melt flow index of 1-4 as measured according to JIS K7210, method of condition 14 and homopolymers are preferred from the viewpoints of well-balanced properties between transparency and moldability.

Description

Detailed Description of the Invention The present invention provides transparency, thermoformability, and safety suitable for press-through pack packaging (hereinafter abbreviated as PTP packaging) used for packaging pharmaceutical tablets, capsules, etc. Concerning superior polypropylene compositions.

Conventionally, hard vinyl chloride resin sheets (hereinafter abbreviated as vinyl chloride sheets) have been mainly used for FTP packaging.

However, the moisture permeability of PVC sheets is too high for pharmaceuticals that are susceptible to deterioration due to moisture, such as aspirin and antibiotics. Furthermore, they are used by laminating polyvinylidene chloride, etc., which have low moisture permeability, which makes them expensive. be. Therefore, there is a desire for a resin sheet suitable for FTP packaging that is cheaper and has lower moisture permeability.

On the other hand, polypropylene sheets have problems with transparency and thermoformability, even though their moisture permeability is lower than that of PVC sheets, and at present they are hardly used in p'rp packaging.

By the way, one way to improve the transparency of polypropylene sheets is to add a nucleating agent such as dibenzylidene sorbitol to polypropylene, and one way to improve thermoformability is to blend polypropylene with polyethylene. However, all of them have advantages and disadvantages; for example, the former has poor moldability, and the latter has poor transparency, which poses problems for use in FTP packaging.

As a method for simultaneously improving the transparency and thermoformability of polypropylene sheets, polypropylene is suitable for FTP packaging due to its hydrological properties, but the sheets obtained by this method are made of normal heptane (hereinafter referred to as n). -HT) elution amount is large, and the standard of Ministry of Health and Welfare Notification No. 20 (abbreviated as HT) is large.
150 ppm or less), and the reality is that they are virtually unusable.

As a result of intensive studies to solve the above problems, the inventors have found 1. The inventors have discovered that by using a specific hydrogenated petroleum resin, a sheet that satisfies the standards of Ministry of Health and Welfare Notification No. 20 can be obtained, and the present invention has been achieved.

That is, in the present invention, 6 to 2 parts of hydrogenated petroleum resin having a softening point of 124°C or higher is added to 100 parts by weight of polypropylene.
This is a polypropylene composition for press-through pack packaging, characterized in that it contains 0 parts by weight.

In the present invention, polypropylene includes α-polypropylene, propylene and ethylene, butene-1, etc.
Random copolymers with olefins can be used. Among them, JIS K7210 condition polypropylene is preferable from the viewpoint of the balance between transparency and moldability. If the MI is less than 1, the transparency will be poor, and if the MI is more than 4, it will become sticky during thermoforming and the moldability will be poor.

Hydrogenated petroleum resins used in the present invention include hydrides of aromatic hydrocarbons and terpene resins having a softening point of 124° C. or higher, preferably 130° C. or higher, and specifically styrene resins. , one or two of various aromatic unsaturated hydrocarbons and/or terpenes such as α-methylstyrene, vinyltoluene, vinylxylene, propenylbenzene, indene, methylindene, and ethylindene.
Hydrogenated resin obtained by polymerizing a mixture of two or more species, and boiling point 2 produced as a by-product during the decomposition and reformation of petroleum.
Examples include hydrogenated resins obtained by polymerizing the portion at 0 to 600°C, particularly 150 to 600°C.

If the softening point of the hydrogenated petroleum resin used is less than 124°C, n
-It is not preferable because the amount of HT elution increases.

The softening point in the present invention is the softening point measured by the ring and ball method of JIS K5902.

In the present invention, the amount of petroleum resin used varies depending on its softening point, but the amount of petroleum resin used is 3 parts per 10 parts by weight of polypropylene.
~20 parts by weight, preferably 6 to 11 parts by weight. If the amount used is less than 3 parts by weight, the effect of improving transparency and thermoformability will be insufficient, and if it is used in excess of 20 parts by weight, thermoformability will deteriorate.

The polypropylene composition of the present invention is obtained by blending polypropylene and hydrogenated petroleum resin together with a stabilizer for polypropylene using a known device such as a Henschel mixer, and then pelletizing the mixture using a known device such as an extruder. After that, it is extruded from a T-die, for example, to form an FTP packaging sheet.

The FTP packaging sheet thus obtained has excellent moisture permeability, transparency, and safety, as well as excellent thermoformability during FTP packaging, and can be put into practical use by being put into a molding machine for PTP packaging.

PTP packaging is a form of packaging in which tablets, capsules, etc. are packaged with a plastic sheet pocket and aluminum foil that seals the pocket. Usually, a thermoplastic sheet is thermoformed, and tablets, capsules, etc. are automatically packed into this. The process is carried out using a high-speed automatic packaging machine that continuously performs the steps of filling, sealing with aluminum foil, making perforations and slits, and punching out the outer periphery.

The PTP packaging sheet obtained from the polypropylene composition of the present invention has excellent formability during thermoforming, and also has excellent thermal adhesion with aluminum foil and punching properties, so it has less uneven thickness. Excellent FTP packaged products can be obtained at high speed. Also 1.
The quality of the resulting FTP packaged product is also excellent in terms of transparency, moisture permeability, and safety.

The present invention will be further explained below with reference to Examples.

Examples 1 to 4 and Comparative Examples 1 to 3 Ditert-butyl-p-cresol 0.1 overlay part 1
, MI containing 01 parts by weight of calcium stearate =
Hydrogenated petroleum resin having the softening point shown in Table 1 was added to 100 parts of the homopolypropylene No. 2 in the amount shown in Table 1, and after mixing in a Henschel mixer, the cylinder diameter was 401. Pellets were obtained by extrusion at 240°C using an extruder.

This pellet was heated to 240℃ using a cylinder with a diameter of 4 with a T-die.
Made into a sheet using an extruder, with a width of 200mm and a thickness of 0.
．． A 25 mm FTP packaging sheet was obtained.

Next, this sheet is transferred to an FTP packaging machine M manufactured by Kanae Co., Ltd.
FTP packaging was performed using 2O00 to evaluate moldability. Further, the transparency, moisture permeability, and amount of n-HT elution of this sheet were also measured. The results are shown in Table-1.

Note that transparency was determined by measuring haze according to ASTM'-D-1003, moisture permeability was measured according to ASTM-E-96, and n-HT elution amount was determined according to Ministry of Health and Welfare Notification No. 20.

Example-5 In Example-1, MI instead of homopolypropylene
Moldability and various physical properties were examined in the same manner as in Example 1, except that a random copolymer with an ethylene content of 1.5 and an ethylene content of 2% by weight was used. The results are shown in Table-1.

Comparative Example 4 For comparison, the moisture permeability of a commercially available hard vinyl chloride resin sheet for press-through packs with a thickness of 0.25 mm was measured, and the value was 5 fl/rr?
24 hours was inferior to that made from the polypropylene composition of the present invention.

Claims (1)

[Claims] 1. Softening point is 12 with respect to 100 parts by weight of polypropylene
A polypropylene composition for press-through pack packaging, characterized in that the hydrogenated petroleum resin having a temperature of 4°C or higher is 3 to 20 parts by weight. 6 parts of dihydrogenated petroleum resin per 100 parts by weight of polypropylene
The polypropylene M composition according to claim 1, wherein the polypropylene M composition has a content of 11 parts by weight.