JPS61155460A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which is harmless to the human body, can retain an excellent antibacterial activity over a long period of time and is suitable for use in the production of articles having excellent physical properties, such as film and flat yarn, by blending a specified compd. as an antibacterial agent with a thermoplastic resin. CONSTITUTION:0.01-1pt.wt. at least one compd. selected from bis(p- chlorophenyldiguanido)-hexane and acid addition salts thereof as antibaterial agent and optionally additives such as antioxidant, ultraviolet absorber, heat stabilizer, antistatic agent, pigment, etc. are dry-blended with 100pts.wt. thermo plastic resin (e.g. PE, PP or PVC) in a blender. Alternately, they are melt- kneaded in a melt extruder.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermoplastic resin composition. Specifically, the present invention relates to a thermoplastic resin composition containing an antibacterial agent in a thermoplastic resin so that when formed into a molded article, it has an antibacterial effect against microorganisms for a long period of time.

[Prior art]

Conventionally, cleaning films, sheets, etc. made of polyethylene resin, polypropylene resin, polyvinyl chloride resin, etc. have been used for storing and packaging various items such as clothing, precision equipment, and garbage. When storing the above items in sealed packaging using packaging materials such as films and sheets,
Especially when the environment is warm and for a long period of time, the contents may become
Bacteria were generated and propagated, and strict quality checks were required for storage management of the contents.

Also, applications other than those mentioned above using thermoplastic resin.

For example, industrial materials such as underground cable jackets and drain pipes, and sanitary products such as slippers and sanitary gloves.

Carpet base materials, construction materials, etc. also contain mold, bacteria,
Due to the action of microorganisms such as yeast, the quality of the product deteriorates and its performance deteriorates, or there are hygienic problems such as stains and odors.

For this reason, attempts have been made to add antibacterial additives to polyolefin resins to inhibit the action of microorganisms.

For example, (1) a method of adding an organic antibacterial agent such as hexachlorophene and a hydrophilic surfactant to polyethylene (Tokukosho!
;,3-41//? (No. 7), (2) A method of adding 10,10'-oxybisphenox arsine as an antibacterial agent to polyolefin (English, Europ@an
Plamtlcm News, March.

1911I, P, cog), etc. have been proposed.

[Problem that the invention seeks to solve]

In the methods (1) and (2) above, the antibacterial agents used in the methods have a toxic effect on the human body, which not only poses problems in handling, but also severely limits the uses of the products.

[Failure to solve the problem]

In view of such prior art, the present inventors have made extensive studies to provide a thermoplastic resin composition that has no toxic effect on the human body and has an antibacterial effect on microorganisms.
The present inventors have discovered that the object can be achieved by blending a specific amount of bis(p-chlorophenyldiguanide)hexane or its acid salt as an antibacterial agent into a thermoplastic resin, and have completed the present invention.

That is, the gist of the present invention is to combine 100 parts by weight of a thermoplastic resin and bis(p-chlorophenyldiguanide) represented by the formula %.
The thermoplastic resin composition comprises 0.07 to 0.07 parts by weight of at least one compound selected from the group consisting of hexane and its acid salts.

The present invention will be explained in more detail below.

Thermoplastic resins used in the present invention include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-7, olefin resin such as ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, vinyl chloride-acetic acid. Vinyl chloride resins such as vinyl copolymers, polystyrene, styrene resins such as acrylonitrile-styrene copolymers, nylon-6, nylon-6
-6, polyamide resins such as nylon/1, polyethylene terephthalate, polybutylene terephthalate, and the like.

In addition, the antibacterial agent used in the present invention is bis(p-chlorophenyldiguanide) represented by the formula %.
Examples include hexane or its acid salts, such as hydrochloride, acetate, and gluconate, and these antibacterial agents may be used alone or in a mixture of two or more fcti.

The blending amount of the antibacterial agent is 0.0/1/part by weight, preferably o, or r, per 100 parts by weight of the thermoplastic resin.
- o, s parts by weight. If the amount of the antibacterial agent is less than the above, the effect of improving the antibacterial properties of the thermoplastic resin composition will be reduced, which is not preferable. Further, even if the amount exceeds the above, no significant improvement in antibacterial properties is observed and economical efficiency is deteriorated, which is not preferable.

The thermoplastic resin composition of the present invention can be prepared by tri-blending the thermoplastic resin and the antibacterial agent using a blender or the like, or by using a conventional melt mixing method such as a Banbury mixer, continuous mixer, mixing roll, or kneading extruder. Melt mixing may be performed by, for example, Alternatively, a masterbatch containing a high concentration of antibacterial agent may be prepared by a so-called masterbatch method, and this may be mixed with the thermoplastic resin during molding.

Various molded products obtained by melt-molding the antibacterial thermoplastic resin composition prepared as described above can retain their antibacterial properties for a long time, and do not deteriorate the physical properties of the product. . Therefore, the thermoplastic resin composition of the present invention can be used in various fields such as film products, flat yarn products, monofilament products, laminate products, coating materials for cables and pipes, and various volatile molded products. can.

Depending on the purpose of use, the thermoplastic resin composition of the present invention may also contain antioxidants, ultraviolet absorbers, heat stabilizers, antistatic agents,
Additives such as pigments can be added as appropriate.

[Effect]

In the present invention, by blending the bis(p-chlorophenyldiguanide) hexane or its acid salt into the thermoplastic resin, the antibacterial effect against microorganisms is maintained for a long time, although it is not clear why. Since the antibacterial agent gradually bleeds from the surface of the plastic resin composition, it is presumed that its antibacterial action can be maintained for a long period of time.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

Example 1 (a) Production of thermoplastic resin composition and film Polypropylene (melt flow index (ASTMD-/
Measured according to 3g): Da, 0? /lθ min, density: θ
,? 0.1 weight ins of bis(p-chlorophenyldiguanide)hexane was added to 100 parts by weight of 00 P/U), mixed uniformly, and kneaded at core aO℃ using a single screw extruder to pelletize it and make it antibacterial. A pellet of a polypropylene resin composition containing the agent was obtained.

The above pellet was put into a modern machine (F') - Company M4'0-φ extruder with an annular slit diameter of 100φ and a lip clearance of 0.
．． Using an inflation molding machine equipped with a 7tm inflation die and a cooling air ring, the extrusion temperature is OC1 extrusion #Llyu kp/hr, blow-up death 〇, and frost line height! rQcrn, withdrawal speed/u
, inflation molded under conditions of 3m7 minutes, thickness S
A blown film of Oμ was obtained.

(b) Evaluation of antibacterial properties A solution of Staphylococcus aureus at a concentration of /X10'' cells/ld was mixed with 100 ml of Trypto-Sawya agar medium at a ratio of 0.1- to Trypto-Sawya Toten medium containing Staphylococcus aureus. C (hereinafter abbreviated as test medium solution) was prepared.

The test medium solution 10- was placed in a Petri dish to form a thin # medium, and then a piece of film (length 3
After placing a film (size: cm After that,
The cells were cultured at 37°C for an hour and the presence or absence of inhibition zone formation was observed.

The results are shown in Table 1.

Examples U and 3 Same as Example 1 except that the antibacterial agent was co-tetrahydrochloride (Example Y) or co-acetate (Example J) of bis(p-chlorophenyldiguanide)hexane. This was done in the same manner as in step 1. The results are shown in Table 1.

Example D ~ 6 In Examples / ~ 3, low density modified polyethylene (melt index (JIS KA7A) was used instead of polypropylene).
Measured with i'toc according to OK): s,.

y-710 minutes, density: 0. ? The process was carried out in the same manner as in Example 1'-3, except that the film was formed using the extrusion temperature/AOC and the frost line height of 5 crn. The results are shown in Table 1.

Example 7 Polypropylene (melt flow index (ASTM)
Measured according to D-128K): ti, o Pyi
.

min, density: o, qooy-7cta) ioo heavy weight bis(p-chlorophenyldiguanide) hexane 0.0
Add 7 parts by weight, mix uniformly and use a single screw extruder to
The mixture was kneaded at 0°C and pelletized to obtain pellets of a polypropylene resin composition containing an antibacterial agent.

The above pellet was placed in a cod extruder manufactured by Modern Machinery Co., Ltd. with an annular slit diameter of 100 Wφ and a lip clearance of 0. f
Extrusion using an inflation molding machine equipped with an AX inflation tie and cooling air ring! lu
QC1 extrusion amount/λIce/hr, blow-up ratio 1.0, frost line height gQ(M, take-up speed IQ
, a 50μ thick inflation film was formed under the conditions of 3yB1 minute, and this film was further molded to a width of 161II
After IK slitting, this was drawn using an open drawing device fjt at a drawing speed of 100 ml for 1 minute and a drawing ratio of 7 times to obtain a 7-rat yarn having a denier of lθθO.

The obtained flat yarn was cut to a length of Jl”771,
This was replaced with the film piece described in Example 1 (b) K to evaluate its antibacterial properties. The results are shown in Table 1.

Examples j and 9 The same as the examples except that the anti-stimulant was bis(p-chlorophenyldiguanide)hexane cohydrochloride (Example g) or yuacetate (Example q). Proceed as in step 7. The results are shown in Table 1.

Comparative Examples 1 to 3 Comparative Examples 1 to 3 were carried out in the same manner as in Examples 1 to 1, except that no antibacterial agent was added in Examples 1 to 3. The results are shown in the */ table.

〔Effect of the invention〕

In the present invention, by blending a specific substance into a thermoplastic resin, it is possible to obtain a thermoplastic resin composition that has an antibacterial effect against microorganisms for a long period of time.

The thermoplastic resin M#:#lJ of the present invention is used for film, flat layer 7,
It can be used as molded products such as monofilament and laminate.

Applicant: Mitsubishi Chemical Industries, Ltd. Agent: Patent Attorney Hase - (1 other person)

Claims (1)

[Claims] (1) 100 parts by weight of thermoplastic resin and bis(p-chlorophenyl diguanide) represented by the formula ▲ Numerical formula, chemical formula, table, etc. ▼
1. A thermoplastic resin composition comprising 0.01 to 1 part by weight of at least one compound selected from the group consisting of hexane and its acid salts.