KR0169178B1 - Resin composition for video and audio tape cassette - Google Patents

Abstract

FIELD OF THE INVENTION The present invention relates to a composite resin composition suitable for video and audio tape cassette applications, comprising organic or inorganic powders as fillers in polypropylene resins or polyethylene resins, and lubricants as primary additives, primary antioxidants, secondary antioxidants, and long-term heat-resistant materials. , Composite resin composition prepared by adding proper amount of UV stabilizer, antistatic agent, lubricant, nucleating agent, interfacial adhesive, foaming agent, elastic body, etc., has rigidity, impact resistance, heat resistance, abrasion resistance, glossiness, acoustic properties, low distortion, whitening Its excellent appearance, dimensional stability, adhesiveness, printability, and molding productivity make it attractive in appearance and inexpensive, making it very useful for video and audio tape cassettes.

Description

Composite resin compositions for video and audio tape cassettes

1 is an exploded perspective view showing a part of a video tape cassette based on a conventional styrene resin,

FIG. 2 is a perspective view and a cross-sectional view showing the hub and flange parts of the reel winding the tape of the cassette components of FIG.

3 is a perspective view of an integrally molded video tape cassette based on a conventional styrene resin,

FIG. 4 is a photograph showing a video tape cassette manufactured from a mold using a conventional cirene resin, wherein the lower part is made of styrene resin and the upper part is made of the composite resin according to the present invention.

FIELD OF THE INVENTION The present invention relates to composite resin compositions for video and audio tape cassettes, more particularly stiffness, impact resistance, heat resistance, abrasion resistance, gloss, acoustic properties, low distortion, whitening resistance, dimensional stability, adhesion, printability And composite resin compositions having excellent molding productivity, beautiful appearance, and low price, which are suitable for video and audio tape cassette applications.

In general, high density polyethylene and polypropylene in polyolefin resins are relatively excellent in mechanical properties and are suitable for molding various parts requiring rigidity. In addition, it is easy to complex with heterogeneous inorganic fillers, and the composite resin thus prepared has been developed and used as a replacement thereof in the field where general-purpose engineering plastic-styrene-based resin or nylon resin is used because heat resistance and rigidity are increased.

The composite resin is a material based on a polymer resin and trained with different types of fillers and / or reinforcing materials or mechanically finely dispersed using an extruder, and means a material given new properties that cannot be expressed by the resin itself. When producing such a composite resin, the type, property, size, content, etc. of the base resin, filler and / or reinforcing material to be used are selected according to the required characteristics of the final molded product. In particular, since the composite resin is greatly affected by the processing conditions, the type and processing conditions of the mixing equipment should be appropriately selected so that the desired physical properties can be improved by the filler while maintaining the processability and reproducibility of the resin itself. In addition, the type and amount of additives added to prevent deformation and aging of raw materials due to heat or pressure during mixing and molding are also important variables that determine the properties of the composite resin, and are present between the resin component and the filler component. Since the adhesive force of the interface also affects the physical properties of the resulting composite resin, it is necessary to consider such additives and interfacial adhesive force when preparing the composite resin.

On the other hand, among various molded articles using resin, in the field of audio and video tape, molding characteristics such as balance of mechanical properties such as stiffness and impact resistance, surface characteristics such as hardness and abrasion resistance, low distortion, whitening resistance, dimensional stability and high-speed injection properties Simultaneously required, conventionally, styrene resins such as acrylonitrile butadiene styrene resin, impact resistant polystyrene resin and the like have been mainly used.

However, such a styrene resin has a disadvantage that the price is high, and efforts to replace raw materials have continued in the field of audio tape cassettes. For example, in European Patent Publication No. 501 405 and Japanese Patent Laid-Open No. 3-64339, a composite resin is prepared by mixing carbonaceous calcium or talc with a base resin, but the composite resin thus prepared has an advantage of low cost. There are problems such as poor moldability, complexity of process, poor injection productivity, limitation of application to some parts, and poor surface properties.

In addition, research is being actively conducted to replace raw materials in the field of video tape cassettes, which are relatively thinner and larger in size than audio tape cassettes, and which require high strength, beautiful appearance, high-speed injection properties, and precise assembly. 1 and 2 are diagrams showing components of a video tape cassette based on a conventional styrene resin. In FIG. 1, the parts of the video TFT cassette are shown, 1 is a cover part for preventing contamination by dust, and is mainly made of styrene resin, and 2 is an upper part constituting the main body of the cassette. 3 is mainly made of transparent styrene resin as a window having transparency, and 4 is made mainly of styrene resin as a lower part constituting the main body of the cassette. FIG. 2 shows the components of the reel winding the tape, which are inserted between the upper part 2 and the lower part 4 of the cassette during assembly. In FIG. 2, 5 and 6 are reel hub parts made mainly of styrene resin, and 7 are flange parts of reel made mainly of transparent styrene resin. An integrated video tape cassette comprising such components is illustrated in FIG. 3.

As an example of a research work for producing such a biotape cassette using a raw material other than the conventional styrene resin, International Publication No. 94-9494 utilizes the hinge properties of a high density polyethylene resin and a polypropylene resin. A product that was moldable and recyclable was produced. However, this product has a lack of rigidity compared to a cassette manufactured using a conventional styrene resin, shrinkage rate is increased, poor dimensional stability and flatness, poor heat resistance, abrasion resistance, whitening resistance at mold release molding Not only is the condition unstable, but also has a disadvantage in that the product value is deteriorated due to poor appearance. In addition, Korean Patent Publication No. 90-6257, Japanese Patent Laid-Open No. 62-241947, Japanese Patent Application Laid-Open No. 62-257687, Japanese Patent No. 3-290455, Japanese Patent No. 4-80060, and Japanese Patent Publication No. 5-186646 give a modifier to a polypropylene resin. A modified polypropylene raw material prepared by mixing a nucleating agent or a lubricating agent was used, and a product which selectively improved any one of properties such as stiffness, abrasion resistance, or whitening resistance was produced according to a manufacturing method. However, the product manufactured as described above has a problem in that dimensional stability and smoothness are poor due to shrinkage of the resin itself, and the balance between stiffness and impact resistance is poor. In addition, as a recent study, Japanese Patent Application Laid-Open Nos. Hei 4-39756 and Japanese Patent Laid-Open Nos. Hei 4-306247 and Hei 5-159514 have been formulated with a filler such as zinc oxide in a polypropylene resin to solve the shrinkage problem of the base resin. Mixing in a high content has been produced a product excellent in heat resistance and smoothness, but these products are not only the filler is eluted and poor injection properties when used. Higher proportion of raw materials leads to higher product consumption Consumption and transportation costs increase, resulting in increased manufacturing costs compared to conventional styrene resin based products.

Therefore, the present inventors have been studied to solve the above problems and to develop a composite resin that can replace the existing styrene resin with excellent physical properties as a result, organic or inorganic powder as a filler in a polyolefin resin, and Additives such as lubricants, primary antioxidants, secondary antioxidants, long-term heat-resistant agents, UV stabilizers, antistatic agents, lubricants, nucleating agents, interfacial adhesives, foaming agents, elastomers, etc. can be selected and mixed to provide rigidity, impact resistance, heat resistance, abrasion resistance, It has been found that the composite resin composition suitable for the production of video and audio tape cassettes can be obtained because of its excellent glossiness, acoustic properties, low distortion, whitening resistance, dimensional stability, adhesion, printing and molding productivity and beautiful appearance. The present invention has been completed.

Accordingly, it is an object of the present invention to provide a video and audio tape with excellent rigidity, impact resistance, heat resistance, abrasion resistance, gloss, acoustic properties, low distortion, whitening resistance, dimensional stability, adhesion, printability, and molding productivity and beautiful appearance. It is to provide a composite resin composition for a cassette.

In the present invention to achieve the above object, 660 to 97 parts by weight of a polyolefin resin; 3 to 40 parts by weight of organic or inorganic filler; And at least one additive selected from the group consisting of stearin-based organic lubricants, phenolic primary antioxidants, phosphorus or amine secondary antioxidants, sulfur-based long-term heat-resistant agents, amine-based ultraviolet stabilizers, and glycerol-based or carbon black antistatic agents. It provides a composite resin composition for a video and audio tape cassette, including 3.0 parts by weight.

The composition includes polypropylene or polyethylene wax, ethylene bisstearate or molybdenum sulfide, sorbitol or banjoin-based nucleus, silane or titanium coupling agent, organic or inorganic blowing agent, ethylene-flophilene or ethylene-propylene-diene thermoplastic It is preferable that at least one additive selected from the group consisting of polyolefins modified with rubber, maleic acid or carboxylic acid and styrene-based modifiers is further included within 35 parts by weight based on 100 parts by weight of the polyolefin resin including the filler.

In the present invention, by mixing an appropriate amount of various organic and inorganic fillers and a small amount of additives with polyolefin resin as the base resin, the physical properties of the base resin are improved, and the ultrafine foamability, elastic absorption effect and crystallinity inside the resin are optimized. The lubricity was increased and the interface adhesion between the resin and filler was optimized to make it particularly suitable for video and audio tape cassettes.

The polyolefin resin used as the base resin of the composite resin composition of the present invention has a melt index of 3 to 60 g / 10 min and an ethylene content of 0 to 20 wt% polypropylene resin, or 190 ° C. to 2.16 kg at a load of 230 ° C. and 2.16 kg. Melt index of from 5 to 50 g / 10 min at load, or a polyethylene resin or mixture thereof.

In the composite resin composition according to the present invention, the organic and inorganic fillers participating in the polyolefin resin as described above are calcium carbonate, talc, silica, graphite, barium sulfate, mica, pearlite, wollastonite, hollow glass sphere, hand made organic roux, clay At least one selected from the group consisting of wood flour and rice husk, the particle size is preferably in the range of 0.5 to 200㎛.

The polyolefin resin and these fillers are added in amounts of 60 to 97 parts by weight and 3 to 40 parts by weight, respectively, and may be added and mixed, for example, in the following amounts; 3 to 35 parts by weight calcium carbonate, 3 to 35 parts by weight talc, 3 to 30 parts by weight silica, 3 to 30 parts by weight graphite, 3 to 20 parts by weight barium sulfate, 3 to 25 parts by weight mica, 3 to 30 parts by weight perlite , 3 to 20 parts by weight of wollastonite, 3 to 20 parts by weight of hollow glass balls, 3 to 20 parts by weight of hollow glass balls, 3 to 30 parts by weight of clay, 3 to 30 parts by weight of wood flour and 3 to 30 parts by weight of chaff.

In the composite resin composition of the present invention, in addition to the organic or inorganic filler, a polyolefin resin including a stearin-based organic lubricant, a phenolic primary antioxidant, a phosphorus or amine secondary antioxidant, a sulfur-based long-term heat-resistant agent and an amine ultraviolet stabilizer 0.05 to 0.5 parts by weight each of 100 parts by weight, and 0.05 to 3.0 parts by weight of glycerol crab or carbon black antistatic agent and 0.05 to 3.0 parts by weight of glycerol or carbon black antistatic agent are added. In addition, the composite resin composition of the present invention contains 0 to 15 parts by weight of polypropylene or polyethylene wax, 0 to 5 parts by weight of ethylenebisstearate or molybdenum sulfide, 0 to 3 parts by weight of solitaire or benzoin-based nucleating agent, 0 to 2 parts by weight Polyolefins modified with silinic or titanium coupling agents, 0 to 5 parts by weight of organic or inorganic blowing agents, 0 to 10 parts by weight of ethylene-propylene-based functional ethylene-propylene-diene thermoplastic rubbers, 0 to 25 parts by weight of maleic acid or carboxylic acid And at least one additive selected from 0 to 35 parts by weight of a styrenic modifier /

The styrene-based modifiers added to the composite resin composition of the present invention include K-resin, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-methylene-butylene-styrene block copolymer, and the like. Mixtures are included.

As described above, the composite resin composition prepared by mixing the filler and the additive with the polyolefin-based resin according to the present invention has a specific gravity of 0.93 to 1.3 g / cc, preferably 1.00 to 1.04 g / cc.

The composite resin composition of the present invention is prepared by adding the above-mentioned fillers and additives to the polypropylene or polyethylene resin as described above and mixing them using a semi-condenser, an extruder, or the like. The composite resin composition thus prepared is manufactured into injection or compression specimens using an injection machine or a compressor to perform various physical property evaluations, and is molded into desired video and audio tape cassette parts by conventional molding methods such as injection molding.

4 is a diagram illustrating a video tape cassette in which a lower part is made of styrene resin and an upper part is made and assembled with the composite resin composition of the present invention. That is, the composite resin composition of the present invention is applied to a mold using a conventional styrene resin without the need for modification or replacement of the mold, and has excellent glossiness, formability, dimensional stability, granularity and smoothness as in the styrene resin. It can be seen that. Therefore, the composite resin composition of the present invention is advantageous in terms of the overall cost because it can reduce the mold modification costs due to raw material replacement as well as in terms of production costs.

The composite resin composition of the present invention as described above is superior in strength and impact characteristics and has a specific gravity of 0.93 to 1.3 g / cc, in particular 1.00 to 1.04 g / cc, compared to conventional styrene resins, so that the raw material consumption per molded article Not only is it economical because it is reduced, and the lubricity of the surface is improved without deteriorating the surface hardness, so that the wear resistance, scratch resistance and formability are excellent, the damage of the mold is small, and no whitening phenomenon occurs when taking out. In addition, the shrinkage and dimensional stability is excellent, as well as the smoothness and assembly of the molded article is improved. Even using a mold using a conventional styrene resin, a molded product having the same dimensional specifications as a styrene resin molded product can be obtained, and excellent fluidity enables high-speed injection within 10 seconds, and excellent gloss and antistatic property. Do. Moreover, since the polyolefin resin is used, the manufacturing cost is low, but the hinge property is excellent, and thus the integral molding is possible.

The composite resin compositions of the present invention having many of these advantages over conventional styrenic resins can be used for video and audio tape cassette parts, particularly top parts, bottom parts, covers, reel hubs and reel flanges as shown in FIGS. 1 and 2. Not only can it be usefully used for the manufacture of components, video tape cassettes for integral molding as shown in FIG. 3, housing parts for disposable cameras, and the like. It can also be used as a substitute for applications requiring impact resistant polystyrene and acrylonitrile butadiene styrene resin.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1

70 parts by weight of a high crystalline polypropylene resin and 5 parts by weight of talc as an inorganic filler, 10 parts by weight of graphite, 5 parts by weight of glass spheres, 5 parts by weight of barium sulfate and 5 parts by weight of wood powder and 0.1 parts of amine-based secondary antioxidant as an additive Parts, 0.5 parts by weight of coupling agent and 10.0 parts by weight of thermoplastic rubber to prepare a composite resin composition by an extruder, and to produce an injection or specimen using an injection machine or a compressor, and then flexural modulus (FM), Izod impact strength , Surface hardness (Rockwell hardness, RH) and scratch resistance (AS, pencil hardness) were measured. The results are shown in Table 1 below.

In Examples and Comparative Examples, each physical property measurement method is as follows.

F.M. : Measured according to test method I of ADTM D790

Izod: measured according to test method A of ADTM D256

R.H. : Measured according to the test method of ADTM D785

A.S: Place the pencil at 45 ° on the specimen with a thickness of 3 mm, apply a load of 1 kg to the pencil, and move the specimen to measure the hardness of the primary pencil core without grooves on the specimen surface.

Comparative Example 1

Instead of the composite resin composition of Example 1, the characteristics of the tape cassettes made of conventional styrene resins (miwon emulsification MI 250), which are currently used for video tape cassettes, were measured. The results are shown in Table 2 below.

[Examples 2 to 19]

By changing the type and the amount of the used resin, filler and additives used as shown in Tables 1 and 2 below, a composite resin composition was prepared in the same manner as in Example 1 and the results were measured by measuring the respective properties. 2 is shown.

[Comparative Examples 2 and 3]

Instead of the composite resin composition in Example 1, only the existing polyolefin-based resin was used to prepare a specimen and to measure each characteristic.

In Comparative Example 2, homopolymer PP-137 of Daelim Industrial Co., Ltd. and Copolymer 00-246 of Daelim Industrial Co., Ltd. were used in Comparative Example 3.

A: high crystalline polyflopropylene resin, B: homo polypropylene resin,

C: copolypropylene resin, D: polyethylene resin,

E: calcium carbonate, F: talc, G: silica, H: graphite, I: mica, J: glass spheres,

K: wollastonite, L: barium sulfate, M: pearlite, N: hollow glass sphere, O: wood powder,

P: chaff, Q; Clay, R1: metal salt or organic lubricant,

R2: phenol crab primary antioxidant, R3: phosphorus or amine secondary antioxidant,

R4: sulfur type long-term heat resistant agent, R5: amine ultraviolet stabilizer,

R6: glycerol-based or carbon black antistatic agent,

R7: polypropylene or polyethylene wax, R8: ethylenebisstearate

Or molybdenum sulfide, R9: sorbitol-based or metal salt-based nucleating agent,

R10: silane- or titanium-based coupling agent, R11: organic acid-modified polypropylene or organic acid-modified polyethylene, R12: organic or inorganic blowing agent,

R13: thermoplastic rubber, R14 = K-resin

F.M. = Flexural modulus (kg / cm), IZOD = Izod impact strength (kgcm / cm),

R.H. = Rockwell hardness (R scale), A.S. = Scratch resistance (pencil hardness)

As described above, according to the present invention, organic or inorganic powder as a filler in a polypropylene resin or a polyethylene resin, and as an additive, a lubricant, a primary antioxidant, a secondary antioxidant, a long-term heat resistant agent, an ultraviolet stabilizer, an antistatic agent, Excellent mixing of lubricants, nucleating agents, interfacial adhesives, foaming agents, elastomers, etc. with excellent rigidity, impact resistance, heat resistance, abrasion resistance, gloss, acoustic properties, low distortion, whitening resistance, dimensional stability, adhesion, printability and molding productivity It is possible to obtain a composite resin composition suitable for the production of video and audio tape cassettes at a lower cost while having the same physical properties as compared to conventional styrene resins.

Claims (9)

(A) 60 to 97 parts by weight of polyolefin resin: (B) 3 to 40 parts by weight of organic or inorganic filler; (C) polyflopropylene or polyethylene wax, ethylene bisstearate or molybdenum sulfide, sorbitol or benzoin nucleating agent, silane or titanium crab coupling agent, organic or inorganic blowing agent, ethylene-propylene-based or ethylene-propylene-diene thermoplastic 0.01 to 35 parts by weight of at least one additive selected from the group consisting of polyolefins modified with rubber, maleic acid or carboxylic acid and styrenic modifiers; And (D) at least one selected from the group consisting of stearin-based organic lubricants, phenolic primary antioxidants, phosphorus or amine secondary antioxidants, sulfur long-term heat resistant agents, amine ultraviolet stabilizers and glycerol-based or carbon black antistatic agents. Composite resin composition for a video and audio tape cassette housing comprising 0.05 to 3.0 parts by weight of an additive. The composite according to claim 1, wherein the polyolefin resin is a polypropylene resin having a melt index of 3 to 60 g / 10 minutes and an ethylene content of 0 to 20%, a polyethylene resin having a melt index of 5 to 50 g / 10 minutes, or a mixture thereof. Resin composition. The particle of claim 1, wherein the filler is at least one selected from the group consisting of calcium carbonate, talc, silica, graphite, barium sulfate, mica, pearlite, wollastonite, hollow glass spheres, hollow glass spheres, clay, wood flour, and chaff. Composite resin composition, characterized in that the size is in the range of 0.5 to 200㎛. According to claim 3, wherein the addition amount of the filler is as follows based on 100 parts by weight of the polyolefin resin including the filler 3 to 35 parts by weight of calcium carbonate, 3 to 35 parts by weight of talc, silica 3 to 30 Parts by weight, graphite 3-30 parts, barium sulfate 3-20 parts, mica 3-25 parts, pearlite 3-30 parts, wollastonite 3-20 parts, hollow glass sphere 3-20 parts, hollowed glass Sphere 3 to 20 parts by weight, 3 to 30 parts by weight of clay, 3 to 30 parts by weight of wood powder and 3 to 30 parts by weight of chaff. The composite resin composition according to claim 1, wherein the amount of the additive is based on 100 parts by weight of the polyolefin resin including the filler: 0.05 to 0.5 parts by weight of a stearin-based organic lubricant, and 0.05 to 0.5 parts by weight of a phenolic primary antioxidant. 0.5 parts by weight, 0.05 to 0.5 parts by weight of phosphorus-functional amine secondary antioxidant, 0.05 to 0.5 parts by weight of long-term heat resistant agent, 0.05 to 0.5 parts by weight of amine UV stabilizer and 0.05 to 3.0 parts by weight of glycerol-based or carbon black antistatic agent. The composite resin composition according to claim 1, wherein the amount of the additive is based on 100 parts by weight of the polyolefin resin including the filler: 0 to 15 parts by weight of polypropylene or polyethylene wax, ethylenebisstearate or molybdenum sulfide. To 5 parts by weight, 0 to 3 parts by weight of a sorbitol-based or benzoin-based nucleating agent, 0 to 2 parts by weight of a silane or titanium coupling agent, 0 to 5 parts by weight of an organic or inorganic blowing agent, ethylene-propylene or ethylene-propylene-diene 0 to 10 parts by weight of the thermoplastic rubber, 0 to 25 parts by weight of polyolefin resin modified with maleic acid or carboxylic acid, and 0 to 35 parts by weight of styrene modifier. The method according to claim 1, wherein the styrene-based modifier is K-resin, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer or a mixture thereof The composite resin composition characterized by the above-mentioned. The composite resin composition according to claim 1, wherein the specific gravity is 0.93 to 1.3 g / cc. A housing for a video and audio tape cassette made from the composite resin composition of claim 1.