JP2011083972A - Resin cleaner composition and cleaning method for thermoplastic resin processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin cleaner composition that is excellent in cleaning effect, particularly, in cleaning effect of a molding resin containing a coloring agent and prevents fuming during cleaning, and a cleaning method, using the resin cleaner composition, for a thermoplastic resin processing apparatus. <P>SOLUTION: There are provided the resin cleaner composition, and the cleaning method using the resin cleaner composition for a thermoplastic resin processing apparatus. The resin cleaner composition contains 60-2,000 pts.wt. of an olefinic thermoplastic elastomer, containing 10-50 wt.% of polypropylene and 30-60 wt.% of a rubber component, and 0.2-10 pts.wt. of peroxide with respect to 100 pts.wt. of a non-crosslinked polyolefin resin. The composition is configured such that the content weight of the polypropylene is 30-200 when the content weight of the non-crosslinked polyolefin resin is set as 100. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a resin cleaning composition for discharging and cleaning a resin, a colorant, a filler, a mixture thereof, and the like remaining inside a thermoplastic resin processing apparatus after molding, and a thermoplastic resin The present invention relates to a cleaning method for a processing apparatus.

  Thermoplastic resins are used in a wide variety of products such as press-molded products, injection-molded products, extruded products such as films and sheets, and hollow molded products, taking advantage of excellent processability. The design diversification is progressing. As a result, there is a demand for production of a small number of various kinds of molded products, and in a thermoplastic resin processing apparatus, it is necessary to frequently switch resin materials, colors, and fillers. When changing resin materials, colors, fillers, etc., the effect of disassembly and cleaning of the processing machine each time on the molding of the thermoplastic resin base material after the change of the residue of the thermoplastic resin base material before the change However, it is necessary to cool, disassemble, clean, assemble, and heat the processing apparatus, resulting in a decrease in productivity and an increase in cost. Therefore, in order to maintain productivity, resin compositions have been conventionally used as cleaning agents. The cleaning agent has an action of cleaning the inside of the processing apparatus only by being supplied from the resin supply unit and discharged from the processing apparatus in the same manner as the molding resin without disassembling the processing apparatus. The cleaning agent is also effective when disassembling the processing apparatus. That is, a thermoplastic resin base material for molding remains in the thermoplastic resin processing apparatus after the molding process, and when it is cooled for decomposition, the molten resin is solidified, which hinders removal of the screw and the like. However, if the thermoplastic resin substrate for molding inside the processing apparatus is removed using a cleaning agent, the screw can be easily taken out during decomposition.

  The cleaning agent mechanically scrapes the resin composition containing a single resin or colorant or filler remaining inside the thermoplastic resin processing device, particularly the cylinder or screw of an extruder or injection molding machine. It has an effect of performing cleaning by a purging effect) and a wiping action (wiping effect).

  As a detergent composition for maintaining the productivity of a thermoplastic resin processing apparatus, the present inventors disclosed in Patent Document 1 below, a crosslinkable polyolefin resin composition containing a polyolefin resin and a peroxide, and thermoplasticity. And a cleaning composition comprising a support. This cleaning composition mechanically discharges the resin composition containing the resin or colorant and filler remaining inside the thermoplastic resin processing apparatus, particularly the cylinder or screw of an extruder or injection molding machine. Excellent in both action (purge effect) and wiping action (wiping effect), and high cleaning efficiency makes it easy to change the color of the thermoplastic resin for molding, and a cleaning agent in the processing equipment Since there is little remaining of the composition itself, it is possible to start forming after changing the material at an early stage.

  By the way, in recent years, high heat resistance plastics such as polyphenylene sulfide, polyether sulfone, polyarylate, polyether ether ketone, and so-called super engineering plastics are molded using a thermoplastic resin processing device. Technology for producing plastic products is becoming widespread. When a resin having a high melting (softening) temperature, such as super engineering plastic, is injection molded or extruded, generally the resin injection (extrusion) temperature is often 300 ° C. or higher, and inevitably injection (extrusion). Even in the washing step after molding, the washing temperature is often set to 300 ° C. or higher.

  When a cleaning composition containing polyethylene is used as the polyolefin resin, particularly when the cleaning temperature is high, fuming from polyethylene is intense due to the heat generated by the oxidative decomposition reaction and crosslinking reaction of polyethylene, and smoke is generated in the workplace. There was a problem that the working environment was remarkably deteriorated. That is, when a cleaning composition containing polyethylene is used, if the cleaning temperature is about 200 ° C., smoke is not a problem. However, when 250 ° C. is reached, smoke is noticeable, and when 300 ° C. is reached, smoke is extremely intense. . In addition, when the cleaning composition hardens in the thermoplastic resin processing equipment and becomes a so-called dango state, cooling does not proceed and heat accumulates, and further self-heating proceeds, so smoke generation becomes more intense, and the worker May have reached an unbearable condition.

Japanese Patent No. 4076167

  The present invention has been made in view of the above circumstances, and its purpose is to provide a resin cleaning composition that is excellent in cleaning effect, particularly cleaning effect of a molding resin containing a colorant, and can prevent smoke generation during cleaning. And a method for cleaning a thermoplastic resin processing apparatus using the resin cleaning composition.

  As described above, when a thermoplastic resin composition containing an uncrosslinked polyolefin resin and a peroxide is used alone as a resin detergent, and the crosslinking reaction proceeds using an uncrosslinked polyolefin resin, particularly polyethylene, the washing temperature As the temperature rises, fuming becomes intense due to heat generation due to the oxidative degradation reaction and crosslinking reaction of polyethylene. However, as a result of intensive studies by the present inventors, in addition to uncrosslinked polyolefin resin and peroxide, an excellent cleaning effect is exhibited by using an olefin thermoplastic elastomer containing polypropylene and a rubber component in combination. However, it was found that fumes derived from polyethylene can be prevented.

  This invention is made | formed based on the said knowledge, Comprising: The following structures are provided. That is, the resin detergent composition according to the present invention is an olefin-based thermoplastic elastomer 60 to 2000 containing 10 to 50% by weight of polypropylene and 30 to 60% by weight of a rubber component with respect to 100 parts by weight of the uncrosslinked polyolefin resin. The content of polypropylene is 30 to 200, with 0.2 to 10 parts by weight of peroxide and peroxide, and the content of the uncrosslinked polyolefin resin being 100.

  The resin detergent composition is excellent in the cleaning effect, in particular, the cleaning effect of a molding resin containing a colorant. More specifically, the resin detergent composition according to the present invention is a heat containing a colorant and a filler remaining inside the thermoplastic resin processing apparatus, in particular, a cylinder or screw of an extruder or an injection molding machine. It has the effect | action which wash | cleans by the discharge effect | action (purge effect | action) and the wiping effect | action (wiping effect | action) which mechanically scrape out the plastic resin base material. As a result, since the cleaning efficiency is high, it is possible to easily change the color of the molding resin, and since the remaining resin cleaning composition in the processing apparatus is small, start molding after changing the material at an early stage. be able to.

  Moreover, the resin cleaning composition which concerns on this invention contains 0.2-10 weight part of peroxides with respect to 100 weight part of uncrosslinked polyolefin resin. When this uncrosslinked polyolefin resin is supplied to a processing apparatus, it is easily melted. The melted uncrosslinked polyolefin resin is easily adapted to a cylinder and a screw, and as a result, a molding resin (in the thermoplastic resin processing apparatus ( Exhibits an effect of wiping (thermoplastic resin substrate). Next, while moving in the thermoplastic resin processing apparatus in contact with a screw or cylinder, the uncrosslinked polyolefin resin is crosslinked by the peroxide, and the resin strength is increased. As a result, the thermoplastic resin processing apparatus is efficiently cleaned by purging the wiping molding resin by exhibiting a strong scraping (purge) action without being easily deformed.

  Furthermore, the resin detergent composition according to the present invention comprises an olefin-based thermoplastic elastomer containing 10 to 50% by weight of polypropylene and 30 to 60% by weight of a rubber component in an amount of 60 to 100 parts by weight based on 100 parts by weight of the uncrosslinked polyolefin resin. Contains 2000 parts by weight. Since the polypropylene contained in this olefinic thermoplastic elastomer has an action of capturing radicals generated during the oxidative decomposition reaction of polyethylene, it is possible to prevent fumes derived from polyethylene. However, when the content of the uncrosslinked polyolefin resin is 100 in the resin detergent composition according to the present invention, the content of polypropylene is 30 to 200. When the content of uncrosslinked polyolefin resin is 100, if the content of polypropylene is less than 30, the effect of preventing smoke generation is reduced, and if it exceeds 200, the purge effect of the resin detergent composition is reduced. In the present invention, the “polypropylene content weight” means the product of the number of parts by weight of the olefinic thermoplastic elastomer and the weight% of polypropylene.

  By the way, if only the oxidative degradation reaction of polyethylene is to be prevented, the fuming of polyethylene can be prevented by adding polypropylene alone to a thermoplastic resin composition containing uncrosslinked polyolefin resin and peroxide. Conceivable. However, as shown in the results of Examples described later, polypropylene decomposes during washing and the melt viscosity is lowered. Therefore, when added alone, the purge effect of the resin detergent composition is lowered. As a result, the polypropylene remains attached to, for example, the groove wall of the screw after washing, and this brings about an undesirable result as a resin detergent.

  However, in the olefinic thermoplastic elastomer used in the present invention, polypropylene and a rubber component are mixed like an alloy, and the rubber component suppresses a decrease in melt viscosity even if the polypropylene causes a decrease in viscosity during the crosslinking reaction. It plays a role and can prevent the cleaning effect from decreasing. That is, in the present invention, the polypropylene, which is a component of the olefinic thermoplastic elastomer, can prevent fuming due to the oxidative decomposition reaction of polyethylene, and the other rubber component can maintain the melt viscosity, and can be washed with resin. The purge effect of the agent composition can be maintained.

  As a result, the resin detergent composition according to the present invention is excellent in the cleaning effect, in particular, the cleaning effect of the molding resin containing the colorant, and can prevent smoke generation during cleaning.

  In the said resin cleaning composition, it is preferable to contain 0.1-3 weight part of at least 1 sort (s) further selected from the group which consists of a lubricant and surfactant with respect to a polymer component total 100 weight part.

  Moreover, the washing | cleaning method of the thermoplastic resin processing apparatus which concerns on this invention supplies the resin cleaning composition in any one of the said to the resin supply part of the thermoplastic resin processing apparatus after shape | molding a thermoplastic resin base material. The thermoplastic resin base material remaining in the thermoplastic resin processing apparatus is discharged and washed together with the resin detergent composition while proceeding with the crosslinking of the uncrosslinked polyolefin resin.

  With the above-described cleaning method, it is possible to clean the thermoplastic resin processing apparatus while preventing smoke generation during cleaning. In addition, with this cleaning method, the thermoplastic resin processing device after molding the thermoplastic resin base material can be cleaned in a short time, improving the resin molding productivity and consuming the resin detergent composition. The amount can also be reduced.

  The method for cleaning a thermoplastic resin processing apparatus according to the present invention is particularly suitable for the crosslinking of uncrosslinked polyolefin resin at a temperature at which fuming due to the oxidative decomposition reaction of polyethylene becomes significant, specifically, at a cleaning temperature of 250 ° C. or higher. It is preferable to carry out the polymerization while proceeding with the crosslinking of the uncrosslinked polyolefin resin at a temperature of 300 ° C. or higher. Moreover, in the washing | cleaning method of the thermoplastic resin processing apparatus which concerns on this invention, as an upper limit of washing | cleaning temperature, it is preferable to set it as 400 degrees C or less in order to prevent the burning of a resin detergent composition.

  Examples of the uncrosslinked polyolefin resin constituting the thermoplastic resin composition of the present invention include polyethylene, ethylene and a small amount (generally 0.1 to 15% by weight, preferably 0.5 to 6% by weight) of propylene and butene. And the like and other monomers.

More specifically, polyethylene resins such as ultra low density polyethylene, low density polyethylene (LDPE), medium density polyethylene, and high density polyethylene (HDPE), ethylene / propylene copolymer, ethylene / vinyl acetate copolymer (EVA) And ethylene / acrylic acid copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl acrylate copolymer, and ethylene / methyl methacrylate copolymer. These polyolefins may be used alone or in combination of two or more. The uncrosslinked polyolefin resin preferably has an MFR value of 0.01 to 10 (g / 10 minutes), more preferably 0.01 to 5 (g / 10 minutes).

  As the peroxide constituting the thermoplastic resin composition of the present invention, known peroxides can be used without limitation. Specifically, hydroperoxide, dialkyl peroxide, peroxyketal, diacyl peroxide and the like can be used. More specifically, for example, benzoyl peroxide, methyl ethyl ketone peroxide, t-butyl peroxypivalate, diisopropyl peroxy carbonate, dicumyl peroxide, t-butyl peroxide, t-butyl cumyl peroxide, t-butyl. Hydroperoxide, α, α'-di (t-butylperoxy-diisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5 -Di (t-butylperoxy) hexyne-3, t-butyl-oxybenzoate and the like. These may be used alone or in combination of two or more. In the present invention, the peroxide may be added to the resin detergent composition alone, and a masterbatch of peroxide and rubber or peroxide and uncrosslinked polyolefin resin is prepared in advance. May be added to the resin detergent composition.

  The peroxide preferably has a half-life of 8 to 12 hours at the washing temperature in terms of washing effect. A known mixing apparatus can be used for mixing the uncrosslinked polyolefin or olefinic thermoplastic elastomer and the peroxide, and specifically, a Henschel mixer, a V blender, a tumbler or the like is preferable.

  The compounding quantity of a peroxide is 0.2-10 weight part with respect to 100 weight part of uncrosslinked polyolefin resin, Preferably it is 0.5-5 weight part.

  Examples of the olefinic thermoplastic elastomer contained in the resin detergent composition of the present invention include, for example, polyolefin mainly composed of polypropylene and ethylene propylene methylene linkage rubber (EPDM rubber) exemplified in Plastic Age, July 2009, p. 48. A simple blend of rubber components (non-crosslinked) mainly composed of rubber, a TPV (thermoplastic vulcanized) blended with polyolefin while vulcanizing rubber components such as EPDM rubber (crosslinked), and the end of polymerization of polypropylene And TPO system (Thermoplastic Olefine) blended with a rubber component. In both of these, polypropylene and rubber components are mixed like an alloy, and the viscosity of the rubber component alone is too high by nature, such as injection molding machines, sheet / film and blow molding machines used for ordinary plastic processing. Thus, it is a material that can be processed with the molding machine, which is difficult to process. Olefin-based thermoplastic elastomers are imparted with rubber-like properties when mixed with rubber components, and the texture of soft rubber is manifested.

  In order for the olefinic thermoplastic elastomer to achieve the object as the resin detergent of the present invention, it is necessary to both suppress the oxidative degradation reaction of polyethylene and to maintain a sufficient melt viscosity. These characteristics are determined by the blending ratio of the rubber component and polypropylene in the olefinic thermoplastic elastomer, and the olefinic thermoplastic elastomer used in the present invention is 10 to 50% by weight of polypropylene and 30 to 60% by weight of the rubber component. Containing. When the polypropylene in the olefinic thermoplastic elastomer is less than 10% by weight, it is difficult to suppress the oxidative decomposition reaction of polyethylene, and it is difficult to prevent smoke generation. On the other hand, if the polypropylene in the olefinic thermoplastic elastomer exceeds 50% by weight, it is possible to prevent smoke generation, but the melt viscosity is lowered due to the decomposition of the polypropylene, and the purge effect of the resin detergent composition can be maintained. Disappear. The olefinic thermoplastic elastomer used in the present invention may be composed only of polypropylene and rubber components (100% by weight of polypropylene and rubber components), or in addition to polypropylene and rubber components, for example, It may contain an oil component such as process oil. The oil component may be included in the oil-extended rubber used as the rubber component, or may be included by separately adding to the polypropylene and the rubber component.

  The resin detergent composition according to the present invention comprises an olefin-based thermoplastic elastomer containing 10 to 50% by weight of polypropylene and 30 to 60% by weight of a rubber component in an amount of 60 to 2000% based on 100 parts by weight of the uncrosslinked polyolefin resin. Contains. However, when the content of the uncrosslinked polyolefin resin is 100 in the resin detergent composition according to the present invention, the content of polypropylene is 30 to 200. When the content of uncrosslinked polyolefin resin is 100, if the content of polypropylene is less than 30, the effect of preventing smoke generation is reduced, and if it exceeds 200, the purge effect of the resin detergent composition is reduced. For example, when using an olefinic thermoplastic elastomer containing 10% by weight of polypropylene, in order to satisfy the above relationship between the content of uncrosslinked polyolefin resin and the content of polypropylene, 100 parts by weight of uncrosslinked polyolefin resin is used. Thus, it is necessary to use 300 to 2000 parts by weight of the olefinic thermoplastic elastomer. Here, even in the case where the resin detergent composition contains 2000 parts by weight of an olefin-based thermoplastic elastomer with respect to 100 parts by weight of the uncrosslinked polyolefin resin, an elastomer having a small amount of polypropylene is originally highly viscous, There is no adverse effect on the purge effect.

  In the resin detergent composition according to the present invention, an olefinic thermoplastic elastomer may be used alone, or two or more olefinic thermoplastic elastomers may be used in combination.

  Preferred lubricants added to the resin detergent composition of the present invention include silicone oil, higher fatty acids, metal salts, higher fatty acid amides, waxes and the like. Examples of higher fatty acids include stearic acid, oleic acid, palmitic acid and the like, and examples of metal salts of these fatty acids include alkali metal salts such as sodium salt and potassium salt, alkaline earth such as magnesium salt, calcium salt and barium salt. Metal salts, aluminum salts, zinc salts and the like can be exemplified as suitable ones.

  As surfactants used in place of or together with the lubricant, higher alkylphenyl ethers of polyoxyethylene glycol such as polyoxyethylene nonylphenyl ether, and higher polyoxyethylene glycol such as polyoxyethylene monolaurate Nonionic surfactants such as fatty acid amides such as fatty acid esters, higher fatty acid diethanolamides, higher fatty acid monoethanolamides, and polyoxyethylene fatty acid amides are preferred. As for these, use of a commercial item is preferable for all.

  If necessary, the resin detergent composition of the present invention may contain other thermoplastic resins other than uncrosslinked polyolefin resins, antioxidants, antistatic agents, inorganic fillers, foaming agents, and the like.

  Examples of the thermoplastic resin other than the uncrosslinked polyolefin resin include polymethyl methacrylate resin, acrylonitrile / styrene resin, acrylonitrile / styrene resin / butadiene copolymer resin, polyethylene terephthalate resin, polyarylate resin, polyamide resin and the like. . However, when considering the cleaning effect and smoke resistance, the amount of these thermoplastic resins is preferably 50 parts by weight or less with respect to 100 parts by weight of the uncrosslinked polyolefin resin.

Hereinafter, examples and the like specifically showing the configuration and effects of the present invention will be described.
<Preparation of resin cleaning composition>

Example 1
As uncrosslinked polyolefin resin, 100 parts by weight of high-density polyethylene Novatec HF313 (manufactured by Nippon Polyethylene Co., Ltd .; MFR 0.05), which is a low-fluidity polyolefin resin, organic peroxide park mill D (manufactured by NOF Corporation; dicumyl peroxide) 2 parts by weight, obtained by blending 20% by weight of polypropylene and 40% by weight of process oil while vulcanizing 40% by weight of EPDM rubber, with a Shore hardness A of 77, 230 ° C. and 98N Kao wax EB-G (manufactured by Kao Soap Co., Ltd.) 0.5, a higher aliphatic amide-based lubricant, based on 400 parts by weight of an olefinic thermoplastic elastomer (crosslinking system) having an MFR of 15 and a polymer component of 100 parts by weight The resin detergent composition was manufactured by adding the weight part and mixing with a Henschel mixer.

Example 2
An olefinic thermoplastic elastomer consisting of 60% by weight of uncrosslinked EPDM rubber and 40% by weight of polypropylene, an olefinic thermoplastic elastomer (non-crosslinked system) with a Shore hardness A of 95, MFR at 230 ° C and 98N of 25 ) A resin detergent composition was produced under the same conditions as in Example 1 except that the amount was changed to 250 parts by weight.

Example 3
A resin detergent composition was produced under the same conditions as in Example 1 except that the olefinic thermoplastic elastomer was changed to 200 parts by weight.

Example 4
A resin detergent composition was produced under the same conditions as in Example 1 except that the olefinic thermoplastic elastomer was changed to 750 parts by weight.

Comparative Example 1
A resin detergent under the same conditions as in Example 1 except that the olefinic thermoplastic elastomer was replaced with 400 parts by weight of an olefinic thermoplastic elastomer (non-crosslinked system) consisting of 95% by weight of a crosslinked EPDM rubber and 5% by weight of polypropylene. A composition was prepared.

Comparative Example 2
A resin detergent under the same conditions as in Example 1 except that the olefinic thermoplastic elastomer was replaced with 400 parts by weight of an olefinic thermoplastic elastomer (non-crosslinked system) composed of 30% by weight of crosslinked EPDM rubber and 70% by weight of polypropylene. A composition was prepared.

Comparative Example 3
A resin detergent composition was produced under the same conditions as in Example 1 except that the olefinic thermoplastic elastomer was changed to 100 parts by weight.

Comparative Example 4
A resin detergent composition was produced under the same conditions as in Example 2 except that the olefinic thermoplastic elastomer was replaced with 600 parts by weight.

Comparative Example 5
Example except that in place of the olefinic thermoplastic elastomer, polypropylene having an MFR of 0.5 at 230 ° C. and 21.6 N alone was added in an amount of 300 parts by weight per 100 parts by weight of the uncrosslinked polyolefin resin. A resin detergent composition was produced under the same conditions as in 1.

Comparative Example 6 to Comparative Example 8
A resin detergent composition was produced under the same conditions as in Example 1 except that the olefin-based thermoplastic elastomer was not added. The cleaning temperature was 300 ° C. in Comparative Example 6, 250 ° C. in Comparative Example 7, and 200 ° C. in Comparative Example 8.

<Evaluation method>
(1) Base resin removal evaluation [cleaning and preparation of evaluation sample]
1) Resin molding A mixture obtained by adding 2.5 parts by weight of REMAFIN BLUE 915CG (manufactured by Clariant) to 100 parts by weight of Mitsui Polypro J105W (manufactured by Mitsui Polypro), which is a homopolypropylene, is subjected to mold clamping pressure The temperature of a 55-ton injection molding machine (manufactured by TOSHIBA MACHINERY CO., LTD.) Was raised to 200 ° C. to form 5 plates of 65 mm length × 25 mm width × 1.5 mm thickness.

2) Cleaning After molding, the temperature of the injection molding machine is maintained at the predetermined temperature shown in Table 1, and the molding resin remaining from the injection molding machine is discharged by rotating the screw, and then the resin cleaning composition is charged from a 200 g hopper. Then, the screw was rotated to discharge 100 g of the resin cleaning composition. The screw was once stopped, and after 5 minutes, the screw was rotated again to discharge the remaining resin cleaning composition.

3) Replacement Next, the temperature of the injection molding machine is lowered to 200 ° C., 200 g of Mitsui Polypro J105W, which is the thermoplastic resin of the molding resin after color change, is charged and heated, and the screw is rotated to remain in the injection molding machine. The entire amount of the resin detergent composition was discharged together with the resin.

4) Sample molding 4) -1 Evaluation sample molding As a molding resin after color change, 300 g of a mixture obtained by adding 1.0 part by weight of REMAFIN WHITE EEF90 (manufactured by Clariant), a white pigment masterbatch, to 100 parts by weight of Mitsui Polypro J105W The plate was put into an injection molding machine after washing, and a plate having a length of 65 mm, a width of 25 mm, and a thickness of 1.5 mm was formed. The first three shot molding plates were discarded and the fourth shot molding plate was used as an evaluation sample.
4) -2 Standard sample molding

  2) Without supplying cleaning, 300g of Mitsui Polypro J105W, which is a thermoplastic resin for molding after color change, is supplied, and the screw is rotated and completely discharged. Then, the screw is removed and cleaned with a metal brush. The molding resin was completely removed. After the cleaning screw is attached to the injection molding machine and 300 g of the resin composition for molding after color change described in 4) -1 is supplied and discharged, the above 4) -1 is performed. Molded as described, the fourth shot molding plate was the reference sample.

[Evaluation of cleaning effect]
The hue of the fourth shot molding plate was measured to evaluate the cleaning effect of the resin detergent composition. The hue was measured using a spectrophotometer (manufactured by Minolta), and the color difference (ΔE) value was obtained from the hue of the evaluation sample and the reference sample by the L * A * B * display system of JIS Z 8730. The smaller the ΔE value, the better the cleaning effect. When the ΔE value is 2.5 or less, the evaluation is ○, and when it exceeds 2.5, the evaluation is ×.

(2) Detergent evaluation [cleaning and preparation of evaluation samples]
1) Resin molding Mixture obtained by adding 1.0 part by weight of REMAFIN WHITE EEF90 (manufactured by Clariant), a white pigment masterbatch, to 100 parts by weight of Mitsui Polypro J105W (manufactured by Mitsui Polypro), a homopolypropylene, is subjected to a mold clamping pressure of 55. Using Ton's injection molding machine (manufactured by Toshiba Machine Co., Ltd.), five plates of 65 mm length × 25 mm width × 1.5 mm thickness were molded.

2) Cleaning After molding, the temperature of the injection molding machine is kept at a predetermined temperature, and the molding resin remaining from the molded injection molding machine is discharged by rotating the screw, and then the resin cleaning composition is charged from a 200 g hopper. The screw was rotated to discharge 100 g of the resin cleaning composition. The screw was once stopped, and after 5 minutes, the screw was rotated again to discharge the remaining resin cleaning composition.

3) Replacement Next, the temperature of the injection molding machine is lowered to 200 ° C., and 200 g of polystyrene resin Toyo Styrol MW-1-321 (manufactured by Toyo Polystyrene Co., Ltd.), which is the thermoplastic resin of the molding resin after color change, is charged. The resin cleaning composition remaining in the injection molding machine was discharged together with the resin by rotating the screw and rotating the screw.

4) Evaluation sample molding Toyo Styrol MW-1-321 (manufactured by Toyo Styrene Co., Ltd.) 300 g as a molding resin after color change was put into an injection molding machine after washing, and the length 65 mm × width 25 mm × thickness 1. A 5 mm plate was molded. The first three shot molding plates were discarded and the fourth shot molding plate was used as an evaluation sample.

[Survivability evaluation]
1) Visual observation of screw groove The screw groove was visually observed when the screw was pulled out during the standard sample forming of 4) -1, and the remaining presence or absence in the screw groove was checked. The case where the remainder in the screw groove was hardly observed was indicated as ◯, the case where it was slightly recognized as Δ, and the case where it was clearly recognized as X.

2) Molded plate observation It was evaluated whether the resin detergent composition which visually used the above-mentioned fourth shot molded plate remained. When the resin detergent composition remains, the detergent stains in the transparent polystyrene resin. The evaluation results are indicated by ○ when the stain of the cleaning agent is not recognized, △ when it is slightly recognized, and × when it is clearly recognized.

(3) Evaluation of smoke generation The state of smoke generation at the time of discharging the resin detergent composition in 2) of the evaluation of molding resin removal in (1) above was observed.

  A state where smoke generation was not observed or was extremely slight even if it was present was indicated as ◯, a state where smoke generation was observed but not so much abscissa was indicated as Δ, and a state where the work environment was severely deteriorated was marked as ×.

Claims (3)

  60 to 2000 parts by weight of an olefin-based thermoplastic elastomer containing 10 to 50% by weight of polypropylene and 30 to 60% by weight of a rubber component with respect to 100 parts by weight of uncrosslinked polyolefin resin, and 0.2 to 10% of peroxide. A resin detergent composition comprising 30 parts by weight of polypropylene when the content of the uncrosslinked polyolefin resin is 100 and the content of polypropylene is 30 parts by weight.   Furthermore, the resin cleaning composition of Claim 1 which contains 0.1-3 weight part of at least 1 sort (s) selected from the group which consists of a lubricant and surfactant with respect to a polymer component total 100 weight part.   While supplying the resin detergent composition according to claim 1 or 2 to the resin supply part of the thermoplastic resin processing apparatus after molding the thermoplastic resin base material, A method for cleaning a thermoplastic resin processing apparatus, comprising discharging and cleaning the thermoplastic resin base material remaining in the thermoplastic resin processing apparatus together with the resin cleaning composition.