JPS60165220A - Manufacture of polypropylene sheet for press through package - Google Patents

Abstract

PURPOSE:To contrive to obtain stably the sheet excellent in transparence, the resistance for permeability of moisture and thermoforming property, and having sufficient n-HT eluation amount for a by annealing a specified polypropylene resin composition at the temperature equal to or higher than 50 deg.C for 30min or more after said resin composition has benn sheeted at a specified chill roll temperature. CONSTITUTION:The used amount of hydrogenated petrol resin is caused to be 3-20pts.wt. to 100pts.wt. polypropylene resin, and the polypropylene resin and hydrogenated petrol resin are preliminarily constituted into a resin composition with polypropylene resin stabilizer, and then is sheeted and annealed. The sheeting of said resin composition is carried out at the chill roll temperature equal to or higher than 70 deg.C, whereby n-HT eluation amount is decreased. The annealing is carried out at the temperature range of 50-130 deg.C, and the annealing time is caused to be equal to or more than 30min, whereby the polypropylene sheet for PTP package is excellent in the resistance for permeability of moisture, transparence and safety, and the sheet excellent also in thermoforming property at PTP package may be obtained.

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. Regarding superior polypropylene sheets.

Conventionally, hard vinyl chloride resin sheets (hereinafter abbreviated as vinyl chloride sheets) have been mainly used for PTP 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, and they are also used by laminating polyvinylidene chloride, which has low moisture permeability, making them expensive. There are drawbacks. Therefore, there is a desire for a resin sort suitable for FTP packaging that is cheaper and has lower moisture permeability.

On the other hand, although polypropylene sheets have lower moisture permeability than PVC sheets, they have problems with transparency and thermoformability, and are currently hardly used in FTP 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. Although these methods are known, they all 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.

A method for simultaneously improving the transparency and thermoformability of a polypropylene sheet is to add water to polypropylene; it is suitable for FTP packaging due to its optical properties, but the sheet obtained by this method is made using normal heptane (hereinafter referred to as n-HT
It is abbreviated as ) The amount of elution is large, and many of them do not meet the standards (150 ppm or less) of the Ministry of Health and Welfare Notification No. 20, and the reality is that they are virtually unusable.

In order to solve the above problems, the inventors of the present invention have made intensive studies and found that by using a specific amount of hydrogenated petroleum resin, forming a sheet under specific conditions, and annealing it under specific conditions, transparency can be improved.
The inventors have discovered that it is possible to stably obtain a sheet that has excellent moisture permeability and thermoformability, and has an n-HT elution amount that satisfies the standards of Ministry of Health and Welfare Notification No. 20, and has thus arrived at the present invention.

That is, in the present invention, a polypropylene resin composition containing 3 to 20 parts by weight of hydrogenated petroleum resin with respect to [000 weight of polypropylene] is sheeted at a chill roll temperature of 70°C or higher, and then heated at 50°C. This is a polypropylene sheet for press-through pack packaging, characterized by being annealed at the above temperature for 30 minutes or more.

In the present invention, polypropylene includes α-polypropylene, propylene and ethylene, butene-1, etc.
Random copolymers with olefins can be used. Among them, the melt flow index (hereinafter abbreviated as Ml) measured under condition 14 of JIS K7210,
g/'10 minutes. ) is preferably 1 to 4, and homopolypropylene is more preferable in view of the balance between transparency and moldability. M
When I is less than 1, transparency deteriorates, and when MI exceeds 4, it becomes sticky during thermoforming and moldability deteriorates.

The hydrogenated petroleum resin used in the present invention is an aromatic hydrocarbon hydride, a terpene resin hydride, etc.
Specifically, one or two of various aromatic unsaturated hydrocarbons and/or terpenes such as styrene, α-methylstyrene, vinyltoluene, vinylxylene, flobenylbenzene, indene, methylindene, and ethylindene. Hydrogenated resins obtained by polymerizing a mixture of two or more species, and boiling points of 20 to 20, which are by-produced during the decomposition and reformation of petroleum.
Examples include hydrogenated resins obtained by polymerizing fractions at 300°C, particularly from 150 to 300°C.

In the present invention, the amount of hydrogenated petroleum resin used varies depending on its softening point, but is 3 to 20 parts by weight, preferably 6 to 11 parts by weight, based on 100 parts by weight of polypropylene.

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.

In the present invention, polypropylene and hydrogenated petroleum resin are blended together with a stabilizer for polypropylene in a known machine such as a Henschel mixer, made into a resin composition by a known machine such as an extruder, and then a resin composition is prepared using a known machine such as an extruder. It is then sheeted and further annealed.

First, sheeting is performed at a chill roll temperature of 70°C or higher, and by adopting this chill roll temperature, n
-HT elution amount shows a surprising decrease.

Chill roll temperature is 70℃ or higher, preferably 75-125℃
If the temperature is lower than 70°C, the effect will be insufficient and the amount of n-HT eluted will increase.

The sheet obtained above is annealed to further suppress the amount of n-HT elution. In the annealing, the annealing temperature is 50 to 130°C, preferably 80 to 25°G. 5
If the temperature is less than 0°C, the effect is insufficient. Further, the annealing time is 30 minutes or more, more preferably 60 minutes or more. 30
If it is less than 1 minute, the effect is insufficient.

The polypropylene sheet for FTP packaging of the present invention is a sheet that is excellent in moisture permeability, transparency, and safety, and also has excellent thermoformability during P'rP packaging, and has the following characteristics: I) Molding for TTP packaging It is put into a machine and put into practical use.

FTP packaging is a form of packaging in which tablets, capsules, etc. are packaged in plastic sheet pockets and sealed aluminum foil. 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 polypropylene sheet for FTP packaging of the present invention has excellent formability during thermoforming, and also has excellent thermal adhesion with aluminum foil and punching properties, making it an excellent FT with less uneven thickness.
P-packaged products can be obtained at high speed.

Furthermore, the quality of the obtained FTP packaged product is excellent in terms of transparency, moisture permeability, and safety.

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

Example-1 MI containing 0.1 parts by weight of ditert-butyl-p-cresol and 1.1 parts by weight of calcium stearate =
100 parts by weight of homopolypropylene of No. 2, softening point 12
10 parts by weight of hydrogenated petroleum resin at 3°C were mixed in a Henschel mixer, and then extruded at 240°C using an extruder with a cylinder diameter of 40 mm to obtain pellets.

The pellets were rolled at a chill roll temperature of 80°C and an extrusion temperature of 24°C.
Sheeting was performed using an extruder with a cylinder diameter of 40 mm equipped with a T-die set at 0°C, and the width was 20 cm and the thickness was n.
, a 25 mm sheet was obtained.

Next, this sheet was annealed at 80°C for 40 minutes, and P
A polypropylene sheet for TP packaging was obtained.

This sheet is transferred to an FTP packaging machine M20 manufactured by Kanae Co., Ltd.
FTP packaging was performed using 00 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.

Transparency: Haze was measured according to ASTM-D-1 (O3); moisture permeability was measured according to ASTM-B-96; n-HT elution amount was measured according to Ministry of Health and Welfare Notification No. 20.

Comparative Example-1 A polypropylene sheet for FTP packaging was obtained in the same manner as in Example-1 except that annealing was not performed. The moldability and physical properties of the obtained sheet were evaluated. The results are shown in Table-1.

Examples 2 and 3 and Comparative Example 2 Sheets were obtained in the same manner as in Example 1, except that the annealing was waited for the time shown in Table 1. The various physical properties and moldability of the obtained sheet were evaluated. The results are shown in Table-1.

Table 1 Examples 4 and 5 and Comparative Examples 3 and 4 Sheets were obtained in the same manner as in Example 2, except that annealing was performed at the temperatures shown in Table 1. The various physical properties and moldability of the sheet were evaluated. Examples of results
It is shown in Table 2 along with 2.

Table 2 Examples 6 and 7, Comparative Example 5 Sheets were obtained in the same manner as in Example 2, except that the chill roll temperature was set to the temperature shown in Table 1. The various physical properties and moldability of the obtained sheet were evaluated.

The results are shown in Table 3 along with Example 2.

Table 3 Examples 8 and 9 and Comparative Examples 6 and 7 In Example 2, the hydrogenated petroleum resin used was the one with the softening point shown in Table 4 in the amount shown in Table 2. A VC sheet was obtained in the same manner as in Example-2.

The various physical properties and moldability of the obtained sheet were evaluated. The results are shown in Table 4 together with Example 2.

Claims (1)

[Claims] A polypropylene resin composition containing 3 to 20 parts by weight of hydrogenated petroleum resin based on 100 parts by weight of polypropylene is sheeted at a chill roll temperature of 70°C or higher, and then annealed at a temperature of 50 to 130°C for 30 minutes or more. Features and Dimensions Polypropylene sheet for press-through pack packaging.