JP7175958B2 - Screw removal aid - Google Patents

Description

The present invention relates to a screw removal aid for resin processing machines.

In general, resin processing machines such as extruders and injection molding machines are used for coloring, mixing and molding of resins. In these devices, when the predetermined work is completed, the resin itself, additives such as dyes and pigments contained in the molding material, and deteriorated substances such as burns formed from the resin may remain in the molding machine. . These residues are mixed into the molded product during the subsequent resin molding, and may cause poor appearance of the product. Particularly in transparent resins, the inclusion of minute burnt carbides causes the problem of increasing the rate of occurrence of defects in molded products.

Conventionally, in order to remove the residue from the inside of the molding machine, (1) a method using a cleaning agent, (2) the molding material to be used next without stopping the molding machine is filled into the molding machine, and the residue is removed. (3) Manual disassembly of the molding machine, removal of the screw from the cylinder (barrel) and direct cleaning, and the like are adopted.

In recent years, the above method (1) using a cleaning agent has been actively adopted, and has advantages such as no need to stop the apparatus and improved work efficiency. However, if a cleaning agent with a weak detergency is used, not only will the previous molding material remain in the molding machine and mix with the next molding material as foreign matter, but the remaining molding material will be removed when the molding machine is stopped. When the molding machine is started up again, the problem that it deteriorates and mixes as a deteriorated product tends to occur. The above method (2) often requires a large amount of molding material to remove the residue, takes time to complete the work, and has the problem of generating a large amount of waste. . In addition, if the above methods (1) and (2) are used alone, resin that has deteriorated due to long-term use may remain as scorch on the screw surface. ) is still used frequently today.

However, the above method (3) is not efficient because it requires the molding machine to be stopped. Removal of the screw after use of the resin processing machine requires an excessive amount of labor because the screw may become dirty due to residual resin that has flowed before, resulting in a large removal load. In addition, since it is necessary to peel off the resin adhering to the screw after that, if this time and effort are taken into account, it may take a long time to disassemble and clean.

For this reason, a screw removal aid that facilitates screw removal after the material is poured into the resin processing machine before screw removal. By pouring this screw removal aid, it is possible to reduce the removal load and facilitate the next operation.

General-purpose resins such as polyethylene and polypropylene are mainly used as screw removal aids, but they may also be used as removal aids by diverting cleaning agents for resin processing machines.

The phenomenon and technical findings regarding screw removal aids are not widely known, and Patent Document 1 describes the use of metal soaps as lubricants for use as detergents. Moreover, in Patent Documents 2 and 3, it is described that a foaming agent is used. Further, Patent Literature 4 describes a detergent composition using both a foaming agent and a fatty acid metal salt.

JP-A-59-124999 JP-A-10-81898 JP-A-8-295803 Japanese Patent Application Laid-Open No. 2003-276072

When polyethylene or polypropylene, which are general-purpose resins, are used as screw removal aids, it is difficult to remove dirt from the surface of the screw. Not necessarily.
Although it is possible to partially remove dirt on the surface of the screw by using a cleaning agent for resin processing machines, it is difficult to significantly reduce the removal load because the cleaning agent itself adheres to the cylinder (barrel) and screw. . In addition, various additives such as special resins and lubricants that are added to suppress adhesion are effective means for reducing the load when removing the screw, but there are problems such as a decrease in heat resistance and an increase in cost due to additives. There is also In addition, it is difficult to achieve both a cleaning effect and a removal load reduction effect, and problems remain in selecting additives and setting their content.

With the composition described in Patent Document 1, the effect as a lubricant can be obtained, but deterioration may occur at the temperature at which resin processing is performed. Stickiness from deterioration results in increased extraction loads.

Further, in the detergent composition using a foaming agent as described in Patent Documents 2 and 3, the foaming effect caused the resin to adhere to the cylinder remarkably, increasing the removal load. Furthermore, in the detergent composition described in Patent Document 4, the resin deteriorates during disassembly and cleaning, causing the stickiness to be removed and the load to increase.

In addition to discharging resin dirt in the system, the present invention reduces the friction between the cylinder and the screw, greatly reduces the load when pulling out the screw, and greatly reduces the load when pulling out the screw. intended to provide In addition, it also has the property of improving the ease of peeling off the resin adhering to the screw surface after the screw is pulled out, greatly improving the convenience of the screw removal operation that was previously performed, and saving time spent on disassembling and cleaning the device. can be greatly shortened.

As a result of intensive studies to solve the above problems, the present inventors found that a resin composition containing a specific (A) lubricant and (B) a thermoplastic resin can be used as a screw removal aid, and have completed the present invention. developed.

That is, the present invention is as shown below.
[1] Lubricant (A) having a surface tension of 32 mN/m or less and a melting point or softening temperature of 70°C or more as determined by the following method (1) ;
a thermoplastic resin (B) having a surface tension determined by the following method (2) that is at least 5 mN/m higher than that of component (A);
(D) a blowing agent;
(E) made of a resin composition containing a fluororesin,
The mass ratio of the component (A) and the component (D) (mass of the component (A)/mass of the component (D)) is 1 to 300,
A screw removal aid for a resin processing machine, characterized by having a surface tension of 32 mN/m or less after being heated at 80°C for 16 hours as determined by the following method (2) .
Method (1): (A) A plate-shaped test piece obtained by compression molding a lubricant was heated at 40°C for 16 hours, then cooled to room temperature, and the contact angle θ was measured under the following measurement conditions in accordance with JIS R3257. is calculated by the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are applied, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)
Method (2): (B) A plate-shaped test piece obtained by compression-molding a thermoplastic resin or a plate-shaped test piece obtained by compression-molding a screw removal aid was heated at 80°C for 16 hours and then cooled to room temperature. Then, the contact angle θ is obtained under the following measurement conditions in accordance with JIS R3257, and calculated using the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are applied, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)
[2] The screw removing aid for a resin processing machine according to [1], which further contains (C) an inorganic filler.
[3] The resin processing machine according to [1] or [2], wherein the component (A) is at least one selected from the group consisting of organic acids, metal salts of organic acids, and organic acid amides. Screw extraction aid.
[4] The screw extraction aid for a resin processing machine according to any one of [1] to [3], wherein the component (A) is a zinc salt of an organic acid.
[5] The screw removing aid for a resin processing machine according to [3] or [4], wherein the organic acid is a fatty acid.
[6] 0.1 to 30% by mass of component (A), 20 to 70% by mass of component (C), and 0.1 to 20% by mass of component (D) in the screw removal aid. , The screw extraction aid for a resin processing machine according to any one of [2] to [5], containing 0.01 to 5% by mass of the component (E).
[7] The screw for a resin processing machine according to any one of [1] to [6], wherein the component (B) is at least one selected from the group consisting of styrene resins and olefin resins. removal aid.
[8] A method for disassembling and cleaning a resin processing machine, characterized by using the screw removal aid for resin processing machines according to any one of [1] to [7].
[9] A pre-cleaning method for the inside of a resin processing machine before disassembly operation, characterized by using the screw removal aid for a resin processing machine according to any one of [1] to [7].
[10] Lubricant (A) having a surface tension of 32 mN/m or less and a melting point or softening temperature of 70°C or higher as determined by the following method (1) , and a lubricant (A) having a surface tension determined by the following method (2) Use of a resin composition containing a thermoplastic resin (B) having a value greater than that of the component (A) by 5 mN/m or more, (D) a foaming agent, and (E) a fluororesin, wherein the ( The mass ratio of the component A) to the component (D) (mass of the component (A)/the mass of the component (D)) is 1 to 300, and it is used as a screw removal aid for resin processing machines. Use of a resin composition characterized by:
Method (1): (A) A plate-shaped test piece obtained by compression molding a lubricant was heated at 40°C for 16 hours, then cooled to room temperature, and the contact angle θ was measured under the following measurement conditions in accordance with JIS R3257. is calculated by the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are deposited, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)
Method (2): (B) A plate-shaped test piece obtained by compression molding a thermoplastic resin is heated at 80°C for 16 hours, cooled to room temperature, and contacted under the following measurement conditions in accordance with JIS R3257. Find the angle θ and calculate it by the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are deposited, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)

The screw extraction aid for resin processing machines of the present invention can reduce the friction between the cylinder and the screw, in addition to discharging the resin dirt in the system, and greatly reduce the load when extracting the screw. In addition, it also has the property of making it easier to peel off the resin that adheres to the screw surface after the screw is pulled out, greatly improving the convenience of conventional operations in general, and increasing the time spent disassembling and cleaning the device. can be shortened.

EMBODIMENT OF THE INVENTION Hereinafter, the form (henceforth "this embodiment") for implementing this invention is demonstrated in detail. It should be noted that the present invention is not limited to the present embodiment described below, and various modifications can be made within the scope of the gist of the present invention.

[Screw removal aid]
The screw removal aid for a resin processing machine of the present embodiment comprises (A) a lubricant having a surface tension of 32 mN/m or less and a melting point or softening temperature of 70° C. or more, and 5 mN/m It consists of a resin composition containing (B) a thermoplastic resin having a surface tension greater than or equal to, if necessary, (C) an inorganic filler, (D) a foaming agent, and (E) a fluororesin, an antioxidant and at least one selected from heat stabilizers.
Further, the screw extraction aid for resin processing machines of the present embodiment may be simply referred to as an aid.

[Resin composition]
The resin composition of the present embodiment has a surface tension of 32 mN/m or less and a lubricant (A) having a melting point or softening temperature of 70° C. or higher, and a surface tension 5 mN/m or more higher than that of the component (A). It contains (B) a thermoplastic resin. If necessary, at least one selected from (C) an inorganic filler, (D) a foaming agent, and (E) a fluororesin, an antioxidant, and a heat stabilizer may be further contained.
The resin composition of the present embodiment can be used as a screw removing aid for resin processing machines.

((A) lubricant)
(A) The lubricant has a surface tension of 32 mN/m or less and a melting point or softening temperature of 70° C. or more. (A) Lubricant is suitable for the previous screw extraction operation by having the above properties.
(A) Lubricant must have external lubricity, (B) bleed out to the surface of the resin to reduce the load when the screw is pulled out, and (B) contribute to easy peeling of the resin from the metal. is. Therefore, it is effective to use the surface tension as an indicator, and the (A) lubricant having a smaller surface tension than the (B) resin is used.
In order to obtain external lubricity, it is preferable that the surface tension is as low as possible. is.
The surface tension of the (A) lubricant was measured by heating a plate-shaped test piece obtained by compression molding the (A) lubricant at 40° C. for 16 hours, cooling it to room temperature, and measuring the following according to JIS R3257. The contact angle θ can be obtained under the conditions and calculated by the following formula. Specifically, it can be calculated by the method described in Examples below.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are deposited, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersion force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersion force component and polar force component of the surface tension of the liquid, respectively. represents.)

(A) The lubricant should have a melting point or softening temperature of 70° C. or higher, and preferably 90° C. or higher, in order to stabilize deterioration and workability during storage and to fully exhibit the effect of external lubricity. It is preferably 110° C. or higher, and more preferably 110° C. or higher.

(A) Lubricants include, but are not limited to, organic acids, organic acid metal salts, organic acid amides, organic acid derivatives such as organic acid esters, various ester waxes, and olefin waxes. The lubricant (A) is not particularly limited as long as it has a surface tension of 32 mN/m or less and a melting point or softening temperature of 70° C. or more. The surface tension of aluminum oxide is 25 mN/m, and the surface tension of polyolefin wax is 32 mN/m.

As the organic acid in component (A), saturated fatty acids with 9 to 28 carbon atoms, unsaturated fatty acids with 9 to 28 carbon atoms, and benzoic acid are preferred. A part of the chain may have a hydroxyl group. Stearic acid, 12-hydroxystearic acid, palmitic acid, myristic acid, and lauric acid are more preferred from the standpoints of availability and heat resistance. Mixed fatty acids having different alkyl chains may also be used. When the number of carbon atoms is within this range, there is no problem of gas generation or odor, and it is easy to obtain and the properties as a lubricant at the interface function well, which is preferable.

The organic acid may be a metal salt.
Examples of the metal salt in the metal salt of the organic acid include sodium, potassium, lithium, cesium, magnesium, calcium, aluminum, zinc, iron, cobalt, barium salts, etc., and are not limited, but are effective as lubricants. The metal salts of lithium, calcium, barium, zinc or aluminum which perform best are preferred. Among them, metal salts of aluminum and zinc are more preferable because they have low polarity and tend to exhibit external lubricity due to bleeding out from the resin (B). Particularly preferred are zinc metal salts.
The hydrocarbon moiety is preferably stearic acid, 12-hydroxystearic acid, palmitic acid, myristic acid, or lauric acid from the viewpoint of availability and heat resistance, as with the chain length of fatty acids described above.

Organic acid amides in component (A) include saturated fatty acid amides, unsaturated fatty acid amides, saturated fatty acid bisamides and unsaturated fatty acid bisamides having 9 to 28 carbon atoms. Among them, fatty acids having 12 to 18 carbon atoms such as lauric acid, myristic acid, palmitic acid, and stearic acid, unsaturated fatty acid amides such as erucic acid, and saturated fatty acid bisamides such as ethylenebisstearic acid amide are readily available. , and more preferably a saturated fatty acid bisamide such as ethylenebisstearic acid amide, because of its lubricating effect.

Organic acid esters and ester waxes for component (A) include saturated fatty acid esters having 9 to 28 carbon atoms, unsaturated fatty acid esters, medium-chain fatty acid triglycerides, and polyol esters such as hardened oils. Stearic acid stearate, glycerin fatty acid ester monoglyceride, and the like are preferable in terms of availability and lubricating effect.

The olefin wax in the component (A) includes low-molecular-weight polyolefins and the like, and although the type is not particularly limited, general low-density or high-density polyethylene, polypropylene, and the like are used. A molecular weight of about 1,000 to 20,000 in weight average molecular weight and a dropping point of 80 to 180° C. are most likely to produce an effect as a lubricant. In the present specification, the weight average molecular weight refers to a value measured by analysis such as gel permeation chromatography using the most common THF or chloroform, and the dropping point is not particularly defined, but Mettler Toledo A value measured by a method using the DP70 automatic dropping point/softening point measurement system of the company.

(A) Lubricants may be used alone or in combination of multiple types, depending on their effects. In particular, when a styrene-based resin or a polyolefin-based resin is used as the thermoplastic resin (B), other lubricants such as fatty acid derivatives such as fatty acid amides and fatty acids, and polyolefin waxes are added to metal soaps such as fatty acid zinc, fatty acid calcium, and fatty acid aluminum. A combination is preferable because a higher lubricating effect can be imparted. Also, with respect to metal soap, it is possible to further enhance the effect as a lubricant by combining fatty acid zinc with fatty acid calcium, fatty acid aluminum, or the like. In addition, fatty acids are more effective in combination with fatty acid amides and the like.

The content of (A) the lubricant with respect to the total amount of the auxiliary agent (100% by mass) is preferably 0.1 to 30% by mass, more preferably 0.2, from the viewpoint of obtaining a sufficient effect as a lubricant. to 20% by mass, more preferably 0.3 to 10% by mass. When it is this content, since the effect as a lubricating agent can fully be exhibited, the extraction load can be further reduced, and the resin can be more easily peeled off from the screw surface, which is preferable.

((B) thermoplastic resin)
(B) As the thermoplastic resin, a general resin used for injection molding, extrusion molding, or the like can be used. Specific examples thereof include, for example, styrene resins such as polystyrene; polyolefin resins such as polyethylene, polypropylene, and polybutene; acrylic resins such as polymethyl methacrylate; polyvinyl chloride; polyamide resins; polyester-based resin; polyether-based resin; and the like. Among these, styrene-based resins and polyolefin-based resins are preferred.
(B) The thermoplastic resin may be used singly, or two or more of them may be used in combination, or two or more of the same or different resins may be used in combination.

The thermoplastic resin (B) must have a higher surface tension than the lubricant (A), and the larger the difference, the easier it is to obtain the external lubricity of the lubricant (A). The surface tension of the resin (B) is 5 mN/m or more, preferably 10 mN/m or more, and more preferably 12 mN/m or more, as compared to the surface tension of the lubricant (A). In the case of a combination of multiple types of (A) lubricants and multiple types of resins, the surface tension difference between the (A) lubricant with the lowest surface tension and the (B) resin with the highest surface tension is 5 mN/ m or more, preferably 10 mN/m or more, more preferably 12 mN/m or more.
The surface tension of the (B) thermoplastic resin was determined by heating a plate-shaped test piece obtained by compression molding the (B) thermoplastic resin at 80 ° C. for 16 hours and then cooling it to room temperature, according to JIS R3257. Then, the contact angle θ can be obtained under the following measurement conditions, and can be calculated by the following formula. Specifically, it can be calculated by the method described in Examples below.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are applied, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersion force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersion force component and polar force component of the surface tension of the liquid, respectively. represents.)

The styrene-based resin refers to polystyrene or a copolymer of styrene and one or more other monomers in which the content of structural units derived from styrene is 50% by mass or more. Other monomers to be copolymerized with styrene include, for example, acrylonitrile, butadiene, isoprene, and the like. Specific examples of the styrene resin include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene-acrylonitrile copolymer, styrene-isoprene copolymer and the like. Among these, polystyrene, styrene-acrylonitrile copolymer, and styrene-butadiene-acrylonitrile copolymer are preferred.

Polyolefin-based resins include ethylene-based resins, propylene-based resins, and the like, and include copolymer resins of ethylene and/or propylene and α-olefins. Among these, polyethylene is preferable because it has a low residual property in the molding machine and low friction with metal parts when it remains between the cylinder and the screw.

The content of (B) the thermoplastic resin with respect to the total amount of the auxiliary agent (100% by mass) is used as a binder to fully exhibit the effect of the auxiliary agent of the present embodiment, and from the viewpoint of suppressing residual in the cylinder. , preferably 10 to 90% by mass, more preferably 25 to 50% by mass. Within this range, the effect as a binder is improved, and the effect of improving the persistence of the adjuvant itself and reducing the removal load is further improved.

(B) The melt flow rate (MFR) of the thermoplastic resin is preferably 0.005 to 80 g/10 minutes, more preferably 0.01 to 50 g, from the viewpoint of the adhesion of the resin to the cylinder or screw. /10 minutes, more preferably 0.05 to 30 g/10 minutes. Within this range, adhesion to the metal surface is less likely to occur without applying an excessive load to the molding machine, and it is less likely to cause an increase in the removal load due to residue and a decrease in heat resistance.
Although the melt flow rate of a thermoplastic resin varies depending on the resin, it means that it is measured in accordance with ISO-R1133. Temperature 230°C, load 2.16 kg, styrene-acrylonitrile copolymer, styrene-butadiene-acrylonitrile copolymer, typified by styrene resin, temperature 220°C, load 10 kg, polystyrene temperature 200°C, load 5 kg, PMMA 230° C., load of 3.7 kg; for polycarbonate, 300° C., load of 1.2 kg. The conditions for other thermoplastic resins are the values measured according to the standard or MFR conditions recommended by the manufacturer within the standard molding conditions or operating temperature range specified for each resin type.

When using a single thermoplastic resin, it is preferable to use one within the above melt flow rate range, and when using a plurality of thermoplastic resins, those within the above melt flow rate range or the above melt flow rate range It is preferable to adjust the content within the above range by mixing other ingredients. Regarding the melt flow rate in the case of using a plurality of thermoplastic resins, the conditions for the melt flow rate of the most abundant component are used.

((C) inorganic filler)
(C) As inorganic fillers, commonly used calcium carbonate, magnesium carbonate, titanium oxide, zinc oxide, alumina, silica, talc, aluminum hydroxide, magnesium hydroxide, zeolite, wollastonite, mica, diatomaceous earth, Examples include glass fibers, glass powder, glass balls, shirasu balloons, and quex sand. Calcium carbonate, wollastonite, and talc are preferred because they can increase the cost, compatibility with component (A), and the effect of increasing screw slippage.
(C) An inorganic filler can be used individually by 1 type, and can also use 2 or more types together.

The content of (C) the inorganic filler with respect to the total amount of the auxiliary agent (100% by mass) is not limited, but in order to fully exhibit the effect of (A) the lubricant, it is preferably 20 to 70% by mass, More preferably, it is 30 to 60% by mass. Within this range, the dischargeability of the pre-resin by the adjuvant of the present embodiment is improved, and the removal load can be reduced and stains can be easily removed, which is preferable.

Calcium carbonate preferably has an average particle size of 0.1 to 100 μm, more preferably 0.5 to 50 μm.
The average particle diameter (SW diameter) can be calculated from the measurement of the specific surface area by the air permeation method according to JIS M-8511, the image analysis type particle diameter measuring device, or the like.

As the wollastonite, generally commercially available ones can be used, and those having an aspect ratio of 1 to 30, an average fiber length of 800 μm or less, and an average fiber diameter of 1 to 50 μm are preferable. The particle size distribution is measured by an image analysis type particle size measuring device, a rotary tap type sieve shaker, or the like, and particles having sizes within the above range are particularly preferable for obtaining availability and performance.

Talc preferably has an average particle size of 0.1 to 20 μm. The average particle size can be determined by an image analysis type particle size measuring device, a laser diffraction method, or the like.

((D) blowing agent)
The screw removal aid for a resin processing machine of the present embodiment may contain (D) a foaming agent, and (A) the lubricating effect of the lubricant and (D) the friction reduction due to the pore formation of the resin surface by the foaming agent. Due to the synergistic effect of this, it is possible to greatly reduce the pull-out load when pulling out the screw.
(D) As for the foaming agent, any organic or inorganic compound that foams when heated, that is, generates gas can be used.
Organic foaming agents include azodicarbonamide, N,N'-dinitrosopentamethylenetetramine, and the like.
Examples of inorganic foaming agents include inorganic physical foaming agents such as water, hydrogen carbonates such as sodium hydrogen carbonate (sodium bicarbonate) and ammonium hydrogen carbonate, carbonates such as sodium carbonate and ammonium carbonate, and nitrites such as ammonium nitrite. be done. In particular, bicarbonate of sodium bicarbonate and hydrogencarbonate such as ammonium hydrogencarbonate are preferred because of their ease of use and availability.

(D) The shape of the foaming agent is not particularly limited, but it can be used in the form of compounded uniform pellets, masterbatch mixtures, powder mixtures, and the like.

The content of the foaming agent (D) relative to the total amount of the auxiliary agent (100% by mass) is preferably 0.1 to 20% by mass from the viewpoint of obtaining a sufficient foaming effect. 0.1 to 5% by mass is particularly preferable from the viewpoint of obtaining sufficient content. When the content is within this range, the pores of the resin can be appropriately formed, the plasticizing effect is enhanced, and the extraction load can be sufficiently reduced.

In the adjuvant of the present embodiment, the mass ratio of (A) lubricant and (D) foaming agent (mass of (A) lubricant / mass of (D) foaming agent) can further reduce the screw removal load. It is preferably 0.01 to 300, more preferably 0.1 to 100, still more preferably 1 to 50, from the viewpoint of being able to.

((E) at least one selected from the group consisting of fluororesins, antioxidants, and heat stabilizers)
The screw removal aid for a resin processing machine of the present embodiment may contain (E) at least one selected from the group consisting of fluororesins, antioxidants, and heat stabilizers. Addition of fluororesin to suppress adhesion, antioxidant or heat stabilizer to suppress resin deterioration, (B) selection of thermoplastic resin and optimization of compounding ratio to improve adhesion to screw and screw removal By improving the easiness of removing the resin afterward and having excellent removal performance of the previous resin, it is possible to further improve the convenience in the operation of unscrewing the resin processing machine.

(E) The fluororesin is expected to have the effect of suppressing resin adhesion to metal surfaces, and examples thereof include PTFE, PFA, PVDF, ETFE, and PFE. Although not particularly limited, PTFE is preferable because it can suppress resin adhesion to metal surfaces and has relatively excellent heat resistance.
As for the shape, there are various shapes such as pellets and powder, but the powder is particularly preferable in order to disperse uniformly during processing. Although the average particle size is not greatly limited, it is preferably 1,000 μm or less.

The content of the (E) fluororesin relative to the total amount of the auxiliary agent (100% by mass) is preferably 0.01 to 5% by mass, more preferably 0.05 to 2, from the viewpoint of obtaining a sufficient effect. % by mass. Within this range, it is possible to impart ease of peeling off the adhering resin after the screw is pulled out without increasing the load when the screw is pulled out. In addition, since the resin itself can be easily discharged, it is possible to reduce the load of removing the screw due to the residual resin.

(E) Antioxidants or heat stabilizers include general hindered phenols, hydroxylamines, phosphorus, vitamins, etc., but are not particularly limited. In particular, hindered phenol-based antioxidants and phosphorus-based heat stabilizers are preferable in that they can suppress resin deterioration during disassembly and cleaning and deterioration of lubricants such as aliphatic acids and metal soaps, and can suppress an increase in load during removal. .

The content of (E) antioxidant or heat stabilizer with respect to the total amount of auxiliary agent (100% by mass) is preferably 0.01 to 5% by mass, more preferably 0, from the viewpoint of obtaining a sufficient effect. 0.05 to 2% by mass. Within this range, decomposition products of antioxidants and heat stabilizers themselves are less likely to exert an inhibitory effect on other additives (lubricants, etc.), which is preferable.

(Additive)
In order to further enhance the lubricant effect, lubricants other than (A) the lubricant may be used. Examples of the other lubricants include natural waxes such as beeswax. These other lubricants may be used alone or in combination of two or more.
The content of the other lubricants relative to the total amount of the auxiliary agent (100% by mass) is preferably 0.01 to 20% by mass, and more preferably 0.1 to 10% by mass in order to obtain a particularly sufficient effect. preferable. This content does not impair the properties of the active ingredient.

In addition, the adjuvant of the present embodiment may contain lubricating oil such as mineral oil as a binding component.

The adjuvant of the present embodiment is particularly suitable for resin processing machines from the viewpoint of excellent washability, reduced screw extraction load, easy peeling of the resin from the screw after screw extraction, and greatly improved convenience of screw extraction operation. It can be suitably used as a screw removal aid.
Specific examples of the resin processing machine include equipment for processing resin including a screw, and specific examples include an injection molding machine, an extrusion molding machine, and the like.

The adjuvant of the present embodiment has a surface tension of 32 mN/m or less, preferably 28 mN/m or less, more preferably 25 mN/m or less after being heated at 80° C. for 16 hours. When the surface tension is within the above range, the added (A) lubricant functions as external lubricity.
In order to control the surface tension of the adjuvant within the above range, (A) it is necessary to suppress deterioration of the lubricant due to heat.
The surface tension of the adjuvant was measured by heating a plate-shaped test piece obtained by compression molding the adjuvant at 80°C for 16 hours, cooling it to room temperature, and contacting it under the following measurement conditions in accordance with JIS R3257. The angle θ can be obtained and calculated by the following formula. Specifically, it can be calculated by the method described in Examples below.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are applied, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersion force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersion force component and polar force component of the surface tension of the liquid, respectively. represents.)

The adjuvant of the present embodiment preferably has an arithmetic mean roughness Ra of 5 μm or less, more preferably 1 μm or less. If the arithmetic mean roughness Ra is larger than the above range, the influence of variations in surface tension due to surface roughness cannot be ignored, which is not preferable. Especially when the surface is rough, the surface tension tends to be small.
The arithmetic mean roughness Ra of the adjuvant is a value measured using a surface roughness measuring machine in accordance with JIS B 0601 for a plate-shaped test piece obtained by compression molding the adjuvant. Specifically, it can be measured by the method described in Examples below.

(Production method)
The method for producing the adjuvant of the present embodiment is not particularly limited, but for example, a method of premixing the above components in a mixer, kneading and extruding with an extruder and pelletizing, or melt-kneading with a heating roll and a Banbury mixer. , a method of pelletizing later, or the like. As for the foaming agent component, it is preferable to process it under the condition of decomposition foaming temperature or lower in order to suppress deterioration due to foaming. Examples thereof include a method of pelletizing after low-temperature extrusion using an extruder, and a method of kneading with a binder and granulating using a granulator or the like. As the binder component at this time, a solid such as an olefin wax or a lubricant that reaches a melting point at the temperature during granulation can be used.

The material used for producing the adjuvant of the present embodiment may be a combination of several types of pellet samples in the masterbatch system, and there are no particular restrictions on the shape or the components in the masterbatch.

[How to disassemble and clean]
The disassembly cleaning method of this embodiment uses the adjuvant of this embodiment. As the disassembly cleaning method of this embodiment, the auxiliary agent of this embodiment is put into the resin processing machine, the auxiliary agent is poured so that the auxiliary agent touches at least the screw in the resin processing machine, and the resin processing machine is disassembled. is mentioned.

Although the method for disassembling and cleaning the resin processing machine according to the present embodiment is not particularly limited, the following method can be used.
The previous resin is discharged as much as possible, and then the screw removal aid is added. The amount to be charged is preferably about half to twice the capacity of the cylinder, and is charged to such an extent that the former resin is switched to the auxiliary agent. The temperature is preferably the same as the temperature at which the resin was flowed before processing, preferably 140° C. or higher before the resin hardens and lower than 350° C. at which the resin does not decompose. Purge the auxiliary agent, disassemble the die, and remove the screw. By adding a screw removal aid when removing the screw, the removal load can be reduced and the time required for the screw removal operation can be shortened. In addition to this, in the conventional method, stickiness occurs due to the deterioration of the resin and additives, which makes it difficult to peel off the screw surface after it is pulled out. This is improved by the effect of the screw removal aid of the present embodiment, and as a result, it becomes possible to greatly shorten the time required for disassembly and cleaning of the screw.

[Preliminary cleaning method]
The auxiliary agent of the present embodiment is used in the method of pre-cleaning the inside of the resin processing machine of the present embodiment before disassembling the screw. The pre-washing method of the present embodiment includes a step of pre-washing by introducing an auxiliary agent into the resin processing machine, flowing the auxiliary agent so that the auxiliary agent touches at least the screw in the resin processing machine, and further, It may include a step of pulling out from the processing machine.

As the pre-cleaning method, for example, the auxiliary agent of the present embodiment is added as an auxiliary agent during normal disassembly and cleaning, and purging makes it possible to discharge the previous resin, gel derived from it, scorch, etc. is. If the dirt is severe, the amount of dirt to be added can be increased to remove the dirt inside, and the increase in the removal load due to the stickiness caused by the dirt can be reduced by pre-washing.
Further, the pre-cleaning method for a resin processing machine according to the present embodiment may have a step of causing the above-described adjuvant to remain in the resin processing machine.

EXAMPLES Hereinafter, the present embodiment will be described in more detail with reference to examples , reference examples, and comparative examples, but the present embodiment is not limited to the following examples as long as the gist thereof is not exceeded.

Components used in Examples , Reference Examples and Comparative Examples are as follows.
<Component (A): Lubricant>
(A-1) stearic acid (A-2) calcium laurate (A-3) zinc 12-hydroxystearate (A-4) ethylene bis stearamide (A-5) magnesium stearate (A-6) stearic acid Zinc (A-7) Glycerin Fatty Acid Ester Monoglyceride Table 1 shows the melting point or softening temperature (° C.) and surface tension (mN/m) of component (A).

<Component (B): Thermoplastic resin>
(B-1) High density polyethylene (density 0.95 g/cm3, MFR: 0.1 g/10 min, conditions: 190°C, 2.16 kg)
(B-2) polypropylene (MFR: 0.6 g/10 minutes, conditions: 230°C, 2.16 kg)
(B-3) Styrene-acrylonitrile copolymer (MFR: 27 g/10 min, conditions: 220° C., 10 kg)
(B-4) Polystyrene (MFR: 2 g/10 minutes, conditions: 200° C., 5 kg)
(B-5) Styrene-butadiene-acrylonitrile copolymer (MFR: 5 g/10 min, conditions: 220° C., 10 kg)
(B-6) Polymethyl methacrylate (MFR: 4 g/10 min, conditions: 230°C, 3.7 kg)
(B-7) polycarbonate (MFR: 4 g/10 minutes, conditions: 300 ° C., 1.2 kg)
Table 1 shows the surface tension (mN/m) of component (B).

<Component (C): Inorganic filler>
(C-1) Calcium carbonate (average particle size: 10 μm)
(C-2) Talc (average particle size: 5 μm)
(C-3) wollastonite (average fiber length: 200 μm, average fiber diameter: 8 μm, aspect ratio 25)

<Component (D): Foaming agent>
(D-1) sodium bicarbonate (D-2) azodicarbonamide

<Component (E): fluorine-based resin, antioxidant, or heat stabilizer>
(E-1) Polyflon PTFE-M (manufactured by Daikin, average particle size 400 μm)
(E-2) IRGANOX1010 (manufactured by BASF)
(E-3) PTFE fine powder (manufactured by AGC, average particle size 550 μm)

<Additive>
(F-1) Mineral oil (kinematic viscosity 95 mm ² /sec)

Evaluation methods for the adjuvants obtained in Examples , Reference Examples and Comparative Examples are as follows.
[surface tension]
The surface tension (mN/m) of component (A), component (B), and the samples obtained in Examples , Reference Examples , and Comparative Examples were determined as follows.
For component (B) and sample pellets, a predetermined temperature (150 ° C. when resin B-1 is the main composition, 180 ° C. when resin B-2 is the main composition, B-3, B-4, By compression molding at 240 ° C. when the resins B-5 and B-6 are the main composition, and 280 ° C. when the resin B-7 is the main composition), the arithmetic average roughness Ra becomes 1 μm or less. Similarly, a plate-shaped test piece was produced (25 cm x 50 mm). The surface was wiped off with a soft cloth, heated in an oven at 80° C. for 16 hours, and then cooled to room temperature.
For component (A), each sample was heated to the melting point in the same manner, thermally melted, and then subjected to compression molding to prepare a plate-shaped test piece, which was then heated in an oven at 40°C for 16 hours. After that, it was cooled to room temperature.
The contact angle θ of the surface of the object to be measured was measured according to JIS R3257.
The measurement conditions were as follows: Purified water and diiodomethane were used as liquids, the temperature was 23° C., the number of measurements was 5, and the average value was used as the measurement result. The reading time was 1 minute after the droplets were applied, and the measuring device used was FTÅ188 (manufactured by FirstTenÅngstroms).
Using the obtained contact angle θ, the surface tension was calculated by the following formula.
(1+cos θ) γL=2(γs ^D γL ^D ) ^1/2 +2(γs ^P γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)

[Arithmetic mean roughness Ra]
Arithmetic mean roughness Ra (μm) was measured as follows.
The plate-shaped test piece used for the measurement of the surface contact angle was measured under the following conditions in accordance with JIS B 0601.
Measurement conditions: Evaluation length 4 mm, measurement speed 0.3 mm/sec, cutoff value 0.8 mm, number of measurements 3 times, measurement environment: 23 ° C., 50% RH, measuring device: surface roughness contour measuring machine (Surfcom 130A, manufactured by Tokyo Seimitsu Co., Ltd.).

[Screw removal load, ease of resin peeling, washability]
500 g of a black-colored molding material of acrylonitrile-butadiene-styrene copolymer synthetic resin, which is the preceding resin (previous resin), was processed at a cylinder temperature of 240 ° C. by a twin-screw extruder molding machine (PCM30 manufactured by Ikegai Co., Ltd., full-flight screw diameter 30 mm, L/D=40), screw rotation (100 rpm) was continued until the resin was completely discharged, and after rotation was stopped, the same temperature was maintained for 30 minutes.
After that, the temperature of the cylinder was changed according to the usage temperature of the base resin of the adjuvant (the base resin is the resin that is contained most in the composition of the adjuvant, and when multiple resins are included in the same ratio is the resin with the highest operating temperature). 200°C when B-1 and B-2 resins are the main composition; 240°C when B-3, B-4, B-5 and B-6 are the main composition; In the case of the main composition, it was set at 280°C. 500 g of the screw removal aid obtained in Example , Reference Example or Comparative Example was poured in the same manner as the preceding resin.
After that, the resin in the cylinder was discharged as much as possible, the die was removed, and the load when the screw was pulled out was evaluated. When pulling out, a waste cloth was wrapped around the tip of the screw, and the screw was pulled out from the cylinder. At this time, the screw was pulled out at a fixed speed of approximately 1.5 m/10 sec.
－Screw extraction load－
⊚ (excellent): Almost no resin adheres to the groove of the screw, and there is no extraction load.
◯ (slightly excellent): Resin adheres to the groove of the screw, but there is no removal load.
Δ (Good): Resin adheres to the groove of the screw, and there is a pulling load.
x (defective): Resin adheres to the groove of the screw, making it difficult to pull out the screw.
Further, a test for peeling off the resin adhering to the screw after pulling out the screw was carried out according to the following evaluation criteria.
-Removability of resin-
⊚ (excellent): Almost no resin adheres to the groove of the screw, and there is no need to remove it.
○ (slightly excellent): Resin adheres to the screw and can be removed by air blow or by hand.
△ (Good): Resin adheres to the screw and can be scraped off with a brass brush or the like.
x (defective): Resin adheres to the screw and is viscous and difficult to remove.
Thereafter, the preceding resin adhering to the screw surface after the auxiliary agent was peeled off, the residue of the screw removal auxiliary agent, scorching of the screw surface, etc. were directly observed, and the washability was evaluated according to the following criteria.
-Cleanability-
⊚ (excellent): The black colored molding material was completely removed, and no scorching was observed.
◯ (slightly excellent): Almost all of the black molding material was removed, and no scorching was observed.
(triangle|delta) (good): The black colored molding material is removed to some extent, and a little scorch is seen.
x (defective): Black colored molding material remained on the screw, and scorching occurred.

[Examples 1 to 6, 8 to 11, 14 to 19, 21, Reference Examples 7, 12, 13, 20, Comparative Examples 1 to 7]
[Sample 1]
A composition containing each component in the ratio shown in Table 2 was premixed for 5 minutes using a tumbler blender, and the resulting mixture was kneaded with a twin screw extruder. A twin-screw extruder (Toshiba Kikai, TEM26SS) is used for kneading, and the temperature of the cylinder set for each resin (200 ° C. when the main composition is B-1 and B-2, B-3 , B-4, B-5, and B-6 at 240° C. when the main composition is B-4, B-5, and B-6, and 280° C. when B-7 is the main composition) at an extrusion rate of 20 kg/hour. . The melt-kneaded product thus obtained was extruded into a strand, cooled with water, and then cut with a strand cutter to obtain a solid pellet.
[Sample 2]
For those containing a foaming agent, a granulator (Pelleter Double EXD type manufactured by DALTON) is used to melt mineral oil as a binder component and glycerin fatty acid ester monoglyceride as an ester wax to foam. Agent components and inorganic components were added, kneaded, and then granulated. After that, it was cut to a pellet size and dry-blended with the prepared pellets of sample 1 to prepare a mixed evaluation sample.

Table 2 shows the compounding composition ratios and evaluation results of Examples 1 to 6, 8 to 11, 14 to 19 and 21, Reference Examples 7, 12, 13 and 20, and Comparative Examples 1 to 7.

According to the present invention, it is excellent as a screw removal auxiliary agent that can reduce the load of screw removal operation in disassembly cleaning and reduce the labor of general disassembly cleaning of processing machines such as subsequent resin removal and preliminary cleaning of dirt. . As a result, it is possible to shorten the time required for overhauling and cleaning, and to improve the efficiency of a series of operations including resin molding, which is of high industrial value.

Claims (10)

a lubricant (A) having a surface tension of 32 mN/m or less and a melting point or softening temperature of 70° C. or more, as determined by the following method (1) ;
a thermoplastic resin (B) having a surface tension determined by the following method (2) that is at least 5 mN/m higher than that of component (A);
(D) a blowing agent;
(E) made of a resin composition containing a fluororesin,
The mass ratio of the component (A) and the component (D) (mass of the component (A)/mass of the component (D)) is 1 to 300,
A screw removal aid for a resin processing machine, characterized by having a surface tension of 32 mN/m or less after being heated at 80°C for 16 hours as determined by the following method (2) .
Method (1): (A) A plate-shaped test piece obtained by compression molding a lubricant was heated at 40°C for 16 hours, then cooled to room temperature, and the contact angle θ was measured under the following measurement conditions in accordance with JIS R3257. is calculated by the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are deposited, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)
Method (2): (B) A plate-shaped test piece obtained by compression-molding a thermoplastic resin or a plate-shaped test piece obtained by compression-molding a screw removal aid was heated at 80°C for 16 hours and then cooled to room temperature. Then, the contact angle θ is obtained under the following measurement conditions in accordance with JIS R3257, and calculated using the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are deposited, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.) 2. The screw extraction aid for a resin processing machine according to claim 1, further comprising (C) an inorganic filler. 3. The screw removing aid for a resin processing machine according to claim 1, wherein said component (A) is at least one selected from the group consisting of organic acids, metal salts of organic acids, and organic acid amides. The screw extraction aid for a resin processing machine according to any one of claims 1 to 3, wherein the component (A) is a zinc salt of an organic acid. 5. A screw extraction aid for a resin processing machine according to claim 3 or 4, wherein said organic acid is a fatty acid. In the screw removal aid, the component (A) is 0.1 to 30% by mass, the component (C) is 20 to 70% by mass, the component (D) is 0.1 to 20% by mass, the ( E) The screw removing aid for a resin processing machine according to any one of claims 2 to 5, containing 0.01 to 5% by mass of component. The screw extraction aid for a resin processing machine according to any one of claims 1 to 6, wherein the component (B) is at least one selected from the group consisting of styrene resins and olefin resins. A method for disassembling and cleaning a resin processing machine, comprising using the screw removal aid for resin processing machines according to any one of claims 1 to 7. A pre-cleaning method for the inside of a resin processing machine before a disassembly operation, characterized by using the screw removal aid for a resin processing machine according to any one of claims 1 to 7. A lubricant (A) having a surface tension of 32 mN/m or less and a melting point or softening temperature of 70° C. or higher as determined by the following method (1) , and a lubricant (A) having a surface tension determined by the following method (2) of (A ) is the use of a resin composition containing a thermoplastic resin (B) having a value 5 mN/m or more greater than the component (B), (D) a foaming agent, and (E) a fluororesin, wherein the component (A) and the component (D) (the mass of the component (A)/the mass of the component (D)) is 1 to 300, and is used as a screw extraction aid for a resin processing machine. and the use of a resin composition.
Method (1): (A) A plate-shaped test piece obtained by compression molding a lubricant was heated at 40°C for 16 hours, then cooled to room temperature, and the contact angle θ was measured under the following measurement conditions in accordance with JIS R3257. is calculated by the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are applied, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)
Method (2): (B) A plate-shaped test piece obtained by compression molding a thermoplastic resin is heated at 80°C for 16 hours, cooled to room temperature, and contacted under the following measurement conditions in accordance with JIS R3257. Find the angle θ and calculate it by the following formula.
Measurement conditions: Purified water and diiodomethane are used as liquids, the temperature is 23° C., the number of measurements is 5, and the average value is used as the measurement result. The reading time is 1 minute after the droplets are deposited, and the measuring device is FTÅ188 (manufactured by FirstTenÅngstroms) or the like.
Calculation formula: (1 + cos θ) γL = 2 (γs ^D · γL ^D ) ^1/2 + 2 (γs ^P · γL ^P ) ^1/2
(γL is the surface tension of the liquid, γs ^D and γs ^P are the dispersive force component and polar force component of the surface tension of the object to be measured, and γL ^D and γL ^P are the dispersive force component and polar force component of the surface tension of the liquid, respectively. represents.)