JPH04214343A - Laminate for cartridge agent material - Google Patents

Abstract

PURPOSE:To prepare a laminate for a cartridge agent material of superior antistatic performance and its continuance by laminating successively a low density polyethylene layer and a polyethylene composition layer, both of which are provided with specified density, at least on one face of a base. CONSTITUTION:A laminate composed of a low density polyethylene layer of density of 0.925g/cm<3> and a polyethylene resin composition composed of low density polyethylene of density of 0.925g/cm<3> blended with 0.12-0.3wt.% of polyoxyalkylene alkylamine, 0.25-0.4wt.% of higher aliphatic acid glyceryne ester and 0.12-0.2wt.% of higher aliphatic alcohol successively extrusion laminated at least on one face of a base, and is provided with the physical properties of 5X10<10>OMEGA or less of its surface intrinsic resistance. As for low density polyethylene for a raw material of the low density polyethylene layer and the polyethylene resin composition layer laminated on the base, branched low density polyethylene, which is high-pressure-processed low density polyethylene, is used suitably.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate for medicine packaging materials. Specifically, the present invention relates to a laminate for medicine packaging materials using a polyethylene resin that has excellent antistatic performance and durability.

0002

[Prior Art] Polyolefin resin films have excellent electrical insulation properties, but on the other hand, they tend to be charged with static electricity, which makes it easy for powder and dust to adhere to the film surface, reducing workability during film molding and the commercial value of the film. descend. In order to improve these drawbacks, a method has been adopted in which an antistatic agent is added to the polyolefin resin in advance, the resin is kneaded, and then a film is formed.

[0003] Packaging materials for powder packaging, such as medicine packaging materials, coffee powder bags, and bonito flakes bags, are made by extrusion laminating a polyolefin resin film containing an antistatic agent as a base material at high temperatures. Sometimes, the antistatic agent in the film decomposes or scatters due to thermal decomposition, resulting in insufficient antistatic effect, or a significant decrease in antistatic effect in a short period of time, or a decrease in adhesive strength with the base material. There were problems such as.

As a method to solve these problems, the present applicant has first formulated a specific amount of a specific antistatic agent and a higher alcohol into a polyolefin resin, thereby maintaining a constant level even after extrusion lamination molding at high temperatures. It has been found that a laminate film can be obtained which has an antistatic effect, maintains the antistatic effect for a long time, and has sufficient adhesive strength to the base material, and proposed it in JP-A-1-141932.

[0005]

[Problem to be Solved by the Invention] However, although the above proposed method can be applied to applications where a certain level of antistatic performance is desired, it cannot be applied to applications where high antistatic performance is desired, such as those that easily charge or are charged. It is unsuitable for use as medicine packaging materials used to package powdered or granular medicines.

[0006]

[Means for Solving the Problems] The present inventors have conducted intensive studies on packaging materials suitable for the use of drug packaging materials that require high antistatic performance as described above, and have developed a packaging material with a low-density polyethylene layer on the base material. By sequentially extruding and laminating resin composition layers containing specific amounts of a specific antistatic agent and higher alcohol in low-density polyethylene, a laminate with high antistatic effect and excellent durability (laminate for drug packaging materials) The present invention was completed based on the discovery that the following can be obtained.

That is, the gist of the present invention is to provide a low-density polyethylene layer having a density of 0.925 g/cm 3 or less on at least one side of the base material, and a low-density polyethylene layer having a density of 0.925 g/cm 3 or less represented by the following general formula (I). 0.12-0.3% by weight of the indicated polyoxyalkylene alkylamine, 0.25-0.4% of higher fatty acid glycerin ester
% by weight and higher aliphatic alcohol by 0.12 to 0.2% by weight are sequentially extruded and laminated, and the surface resistivity is 5×.
A laminate for medicine packaging material characterized by having physical properties of 1010Ω or less.

[0008]

[Case 2]

(In the formula, R1 represents a linear or branched alkyl group, oxyalkyl group, alkenyl group, or oxyalkenyl group having 8 to 22 carbon atoms, and R2 and R3 represent an alkylene group having 2 or 3 carbon atoms. and m and n are m+
n represents an integer from 2 to 10).

The laminate for medicine packaging materials of the present invention will be explained in more detail below. In the present invention, the base material used is paper such as high-quality paper, kraft paper, glassine paper, cellophane, nylon, polyethylene terephthalate, aluminum foil, etc. Further, as the low density polyethylene that is the raw material for the low density polyethylene layer and the polyethylene resin composition layer to be laminated on the base material, branched low density polyethylene, that is, high pressure low density polyethylene is preferably used.

[0011] The low density polyethylene has a density of 0.
925g/cm3 or less, preferably 0.910 to 0.9
25g/cm3, particularly preferably 0.915-0.9
25 g/cm3, the molecular weight distribution index expressed by {melt index value} x {melt tension value} is in the range of 10 to 40, preferably 10 to 35, and the melt index is in the range of 1 A range of 50 g/10 minutes, preferably 2 to 25 g/10 minutes is suitable from the viewpoint of extrusion lamination moldability. The above melt index is based on the melt index measurement method of JIS K6760 (polyethylene test method), and is 190
The value was measured at 160°C and 2.16 kg, and the melt tension was measured at 160°C and 0.25 kg from the nozzle used in the JIS K6760 melt index measurement method.
This is the tension measured at a distance of 25 cm from the nozzle when extruded at a speed of 1.52 m/min and pulled at a speed of 1.52 m/min.

[0012] If the density of the low-density polyethylene is higher than the upper limit, the adhesion to the paper base material will decrease, and the density of 0.91 g/c
If it is less than m3, moldability will decrease. Furthermore, if the melt index is less than 1 g/10 minutes, the spreadability of the molten film will decrease, while if it exceeds 50 g/10 minutes, the neck-in during melting will be large, making it difficult to produce a high-quality extruded laminate. Furthermore, if the above-mentioned molecular weight distribution index is less than 10, neck-in will be excessive and a draw resonance phenomenon will occur, resulting in poor laminate formability, and if the molecular weight distribution index exceeds 40, the laminate molded product will be This is undesirable as it increases the roughness of the surface.

In the present invention, the polyethylene resin composition layer to be extruded and laminated on the low-density polyethylene layer laminated on the base material is made by combining the low-density polyethylene with an antistatic agent of polyoxyalkylene alkylamine and higher fatty acid glycerin ester. In addition, a mixture containing a higher aliphatic alcohol is used.

As the polyoxyalkylenealkylamine, a compound represented by the above general formula (I) is used. Examples of the compound represented by the general formula (I) include lauryl diethanolamine, myristyl diethanolamine, palmityl diethanolamine, stearyl diethanolamine, oleic diethanolamine, lauryl diisopropanolamine, myristyl diisopropanolamine, palmityl diisopropanolamine,
Examples include stearyl diisopropanolamine and oleic diisopropanolamine. These compounds can be used alone or as a mixture.

Further, as the higher fatty acid glycerin ester, a compound represented by the general formula (II) (wherein R4 is an alkyl group or alkenyl group having 11 to 21 carbon atoms) is used. The compound includes glycerin and carbon atoms having 12 to 2 carbon atoms.
Monoester compounds of up to 2 saturated or unsaturated fatty acids, such as glycerin monolaurate, glycerin monomyristate, glycerin monopalmitate, glycerin monostearate, glycerin monooleate, glycerin monolinoleate, etc. These compounds can be used alone or as a mixture.

Further, as the higher aliphatic alcohol, alcohols having 12 to 30 carbon atoms are preferably used. Examples of the higher aliphatic alcohol include lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, arachyl alcohol, behenyl alcohol, ceryl alcohol, coryanyl alcohol, etc. In particular, stearyl alcohol, cetyl alcohol, myristyl alcohol, lauryl alcohol, etc. Alcohols having 12 to 20 carbon atoms such as alcohol are preferably used.

The above-mentioned polyethylene composition comprises the above-mentioned low-density polyethylene and polyoxyalkylenealkylamine (
a) 0.12-0.3% by weight, preferably 0.12-0.
．． 25% by weight, higher fatty acid glycerin ester (b) 0
．． 25-0.4% by weight, preferably 0.25-0.35
% by weight and higher aliphatic alcohol by 0.12 to 0.25% by weight, preferably 0.12 to 0.2% by weight. If the amount of polyoxyalkylene alkylamine is less than the above range, the antistatic effect and its sustainability will decrease, and if it is more than the above range, the additive will migrate to the interface of the adhesive layer between the resin and the base material when extrusion lamination is performed. , which is not preferable because it causes a decrease in adhesive strength. In addition, if the amount of higher fatty acid glycerin ester blended is less than the above range, the antistatic effect will be small, and if it is more than the above range, the additive will bleed onto the resin surface and cause whitening, which may reduce the antistatic effect or cause extrusion. When laminated, the additive migrates to the interface of the adhesive layer between the resin and the base material, causing a decrease in adhesive strength, which is not preferable. Furthermore, if the amount of higher aliphatic alcohol is less than the above range, the antistatic effect will not be immediate, and if it is more than the above range, the additive will migrate to the interface of the adhesive layer between the resin and the base material when extrusion lamination is performed. , which is not preferable because it causes a decrease in adhesive strength.

The above resin composition can be obtained by a method in which the above components are premixed and then kneaded, or by a method in which the above components are mixed and kneaded all at once. The mixing and kneading may be performed using, for example, a ribbon blender, tumble mixer, Henschel mixer, etc., and the kneading may be performed using an oven roll,
This can be carried out using a Banbury mixer, a single screw extruder, a twin screw extruder, a kneader, or the like.

In the present invention, in order to first extrusion-laminate the low-density polyethylene layer on the base material, extrusion lamination may be performed directly on the base material, but in order to increase the adhesive strength between the base material and the low-density polyethylene layer, It is desirable to perform extrusion lamination after subjecting the adhesive surface of the base material to a known surface activation treatment such as corona treatment, flame treatment, or anchor coating treatment. The anchor coating treatment may be carried out by applying a known anchor coating agent such as polyurethane-based alkyl titanate-based, polyethyleneimine-based, isocyanate-based, etc. to the surface of the base film or sheet.

[0020] The above extrusion lamination molding can be carried out using a known method and apparatus.
A molten thin film is formed by extrusion from the resin at a resin temperature of 300 to 340°C, and the molten thin film is introduced into a pressure roll, while the adhesive surface is subjected to a surface activation treatment, or the above-mentioned base material is guided to the pressure roll without being treated. This is done by pressure laminating with a film or sheet.

[0021] Next, the above polyethylene resin composition layer is extrusion laminated onto the low density polyethylene layer of the base material. That is, the polyethylene resin composition is passed through the extruder die (
Inflation die or T die) to resin temperature 280
This is carried out by extruding at ~300° C. to form a molten thin film, leading the molten thin film to a pressure roll, and pressure laminating it with a low-density polyethylene layer of a base material guided by the same pressure roll.

[0022] The thickness of the low density polyethylene layer and the polyethylene resin composition layer to be extrusion laminated on the above substrate is in the range of 10 to 30 μm, respectively. The surface resistivity of the laminate for medicine packaging material obtained by the above method is 5×1010Ω
Hereinafter, it preferably has a physical property value of 2×10 10 Ω or less, more preferably 1×10 10 Ω or less.

[0023]

[Examples] The present invention will be explained in more detail below based on Examples, but the present invention is not limited by the Examples unless the gist of the invention is exceeded.

Example 1 An isocyanate-based anchor coating agent was applied at a thickness of 3 g/m2 to the adhesive surface of a base film made of cellophane with a thickness of 20 μm, and the melt index =
7g/10min, molecular weight distribution index = 32, melting point = 105°C
high pressure low density polyethylene resin at a resin temperature of 315℃,
It is extrusion laminated to a thickness of 15 μm, and on top of this, 0.15% by weight of stearyl diethanolamine is added to polyethylene having the same physical properties as the above-mentioned high-pressure low-density polyethylene resin.
A resin composition containing 0.30% by weight of glycerin monostearate and 0.15% by weight of stearyl alcohol was extrusion laminated to a thickness of 15 μm at a resin temperature of 290°C. This product was stored at a temperature of 23°C and a humidity of 65%,
Adhesive strength and surface resistivity were measured one week, one month, and three months after molding. The results are shown in Table 2. Note that the adhesive strength and surface resistivity were measured by the following method.

(1) Adhesive strength One of the samples sampled in a rectangular shape with a width of 25 mm,
The base film made of cellophane and the high-pressure low-density polyethylene were peeled off a certain distance from the adhesive surface, and the peeled part was attached to the upper and lower grips of a universal tensile tester, and the film was peeled off at a speed of 300 mm/min in a 180 degree direction. The force when pulled (g/25 mm width) was defined as the adhesive strength. In addition, for use as a medicine packaging material, an adhesive strength of 100 g/25 mm width or more is required.

(2) Surface specific resistance Measured in accordance with JIS K6911 using a super insulation resistance meter manufactured by Ando Electric Co., Ltd. in an environment of 23° C. and 65% RH. In addition, for drug packaging material use, the surface resistivity is 5×
1010Ω or less is required.

Examples 2 to 3 Examples 2 and 3 were carried out in the same manner as in Example 1, except that the blending ratio of additives was changed as shown in Table 1. The results are shown in Table 2.

Comparative Examples 1 to 8 Comparative Examples 1 to 8 Comparative Examples 1 to 8 were carried out in the same manner as in Example 1, except that the blending ratio of additives was changed as shown in Table 1. The results are shown in Table 2.

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

[Effects of the Invention] According to the present invention, a laminate for medicine packaging material having a high antistatic effect can be obtained.

Claims (1)

[Claims] Claim 1: At least one side of the base material has a density of 0.9.
A low density polyethylene layer having a density of 25 g/cm3 or less and a low density polyethylene having a density of 0.925 g/cm3 or less, 0.12 to 0.3% by weight of a polyoxyalkylene alkylamine represented by the following general formula (I), and higher fatty acid glycerin. Polyethylene resin composition layers containing 0.25 to 0.4% by weight of ester and 0.12 to 0.2% by weight of higher aliphatic alcohol are successively laminated by extrusion, and the surface resistivity is 5. A laminate for medicine packaging material characterized by having physical properties of ×1010 Ω or less [Formula 1] (wherein R1 is a straight or branched alkyl group having 8 to 22 carbon atoms, an oxyalkyl group, It represents an alkenyl group or an oxyalkenyl group, R2 and R3 represent an alkylene group having 2 or 3 carbon atoms, and m and n are m+n=2 to 10
represents an integer. )