JP6084060B2 - Lubricant composition for belt conveyor and lubricating method for belt conveyor - Google Patents

Description

  The present invention relates to a lubricant composition for a belt conveyor and a method for lubricating a belt conveyor using the composition. More specifically, plastic, paper, metal, glass and ceramic containers in the manufacturing and filling processes of tea, coffee, tea, milk drinks, carbonated drinks, beer, alcoholic beverages, seasonings, processed foods, etc. TECHNICAL FIELD The present invention relates to a lubricant composition for a belt conveyor used when moving and conveying the belt on a belt conveyor and a method for lubricating the belt conveyor.

  Plastic containers such as polyethylene terephthalate, paper containers, metal containers, glass and ceramic containers, etc. are used for containers for soft drinks, milk, juice, alcoholic beverages, drinks, etc. In the case of handling these containers, a belt conveyor is generally used to move and convey a large number of containers. In such a factory, it is common to operate the belt conveyor continuously, but at this time, deformation of the container, tipping of the container, or the like occurs due to friction generated between the containers or the contact surface between the container and the belt conveyor. In order to prevent such obstacles, it is common to apply or spray a lubricant on the belt conveyor to lower the coefficient of friction.

  As a conventional lubricant for a belt conveyor, it is common to use an aqueous solution of a surfactant. For example, 0.0025% by weight of a polyethylene glycol type nonionic surfactant such as polyoxyethylene alkyl ether of HLB 10-16 produced by adding polyoxyethylene to a primary or secondary alcohol having 12 to 18 carbon atoms Lubricant (Patent Document 1) mainly containing an aqueous solution containing the above, a surfactant such as a nonionic surfactant, a lubricant composition containing a high-boiling solvent and water (Patent Document 2), a glycerin ester, etc. Lubricant composition containing a lipophilic compound, an anionic surfactant and water (Patent Document 3), and a lubricant composition containing an acrylic copolymer and an oily substance in a specific ratio (Patent Document 4) Etc. are known.

Japanese Patent No. 398860 JP2008-106253 Special table 2010-503747 JP2012-153843

However, since the lubricant described in Patent Document 1 is difficult to form a stable lubricating film on the belt conveyor, it is necessary to supply the lubricant as needed, so that a large amount of lubricant is consumed, and the lubricant There is a problem that the cost of water used for dilution and the cost of wastewater treatment are large. On the other hand, since the lubricant described in Patent Document 2 forms a stable lubricating film on the belt conveyor, it can provide relatively long-term lubricity with a small amount of use. However, the lubricating film made of the lubricant of Patent Document 2 has low water resistance, and the lubricating film is easily removed due to dripping of water adhering to the bottle or scattering of water from the manufacturing facility, resulting in a problem that the lubricity is lowered. was there. The lubricants described in Patent Documents 3 and 4 can be used without diluting to form a water-resistant lubricating film. However, there is a problem in storage stability at high temperatures, and PET containing carbonated beverages such as cola. There was a problem in the compatibility with the bottle, and there was a risk of causing stress cracks in the carbonated beverage-containing PET bottle.
The present invention has been made to solve the above-mentioned problems of the prior art, and the object of the present invention is excellent in storage stability and stress cracking property of carbonated beverage-containing PET bottles. It is an object of the present invention to provide a lubricant composition for a belt conveyor capable of forming a water-resistant lubricating film that does not deteriorate the lubricity even when scattered, and a method for lubricating a belt conveyor using the lubricant composition.

In order to solve the above-mentioned problems, the present inventors diligently studied, and as a component (A), at least one oily substance selected from silicone oil, polyalphaolefin, and liquid paraffin as 1 part by mass, (B) An oil-in-water type containing 0.05 to 0.5 parts by mass of a nonionic emulsifier having an HLB of 16 or more as a component and 0.0125 to 900 parts by mass of a polyol as a component (C) A lubricant composition for a belt conveyor, characterized by being an emulsion, is a water-resistant lubricating film that has excellent storage stability, stress cracking properties of carbonated beverage-containing PET bottles, and does not deteriorate even when mixed with water. It has been found that it can be formed.
Further, the present inventors have found a belt conveyor lubrication method suitable for moving and transporting containers using the lubricant composition for belt conveyors, and have completed the present invention.

That is, the present invention
(1) As component (A), it contains at least one oily substance selected from silicone oil, polyalphaolefin, liquid paraffin, and (A) 1 part by mass of component,
As the component (B), and a non-ionic emulsifier HLB is 16 or more 0.1-0.5 parts by weight
(C) A lubricant composition for a belt conveyor, which is an oil-in-water emulsion containing 0.0125 to 900 parts by mass of a polyol as a component,
(2) The lubricant composition for belt conveyors according to (1) above, wherein the polyol of component (C) is at least one selected from glycerin, polyethylene glycol, and sorbitol,
(3) Supply the processing liquid which made (A) component density | concentration in the belt conveyor lubricant composition as described in said (1) or (2) 0.1-5 mass% to the belt conveyor which conveys a container. A lubricating method of the belt conveyor, characterized by imparting lubricity
Is a summary.

  The lubricant composition for belt conveyors of the present invention is not only excellent in storage stability and stress cracking properties of PET bottles containing carbonated beverages, but also excellent in water resistance of lubricant films formed on containers and belt conveyors and scattered. Since there is no possibility that the lubricating film is easily removed by water or the like and the lubricity is not lowered, there is an effect that excellent lubricity is maintained for a long time. Moreover, according to the lubricating method of the belt conveyor of this invention, the lubricity excellent in the belt conveyor which conveys a container in a drink manufacturing factory etc. can be provided.

  The lubricant composition for a belt conveyor of the present invention has at least one oily substance selected from silicone oil, polyalphaolefin, and liquid paraffin as the component (A), and has a HLB of 16 or more as the component (B). A polyol is an essential component as the ionic emulsifier and the component (C).

  In the lubricant composition for a belt conveyor of the present invention, specific examples of the oily substance as component (A) include silicone oil, polyalphaolefin, and liquid paraffin, and these may be used alone or in combination of two or more. May be used in combination, but silicone oil is preferable in terms of compatibility with PET bottles containing carbonated beverages and lubricity. Silicone oils useful in the present invention are water-miscible or water-dispersible silicone oils that are reasonably stable without the use of additional surfactants or emulsifiers such as polydimethylsiloxane compounds. However, even when silicone oil is used, additional surfactants and emulsifiers can also be used. The silicone oil can be preferably represented by the following average unit formula (1).

(Chemical formula 1)
RaSiO _{(4-a) / 2} (1)
(R represents at least one group selected from the group of saturated or unsaturated monovalent hydrocarbon groups having 1 to 18 carbon atoms, and a represents an average value of 1.8 to 2.2. Represents.)

  In the above formula (1), R is at least one group selected from the group of saturated or unsaturated monovalent hydrocarbon groups having 1 to 18 carbon atoms. Examples of such groups include methyl groups, ethyl groups, propyl groups, hexyl groups, octyl groups, decyl groups, dodecyl groups, tetradecyl groups, octadecyl groups and other alkyl groups; cyclopentyl groups, cyclohexyl groups and other cyclohexyl groups; Groups, alkenyl groups such as allyl groups; aryl groups such as phenyl groups and tolyl groups; aralkyl groups such as 2-phenylethyl groups and 2-methyl-2-phenylethyl groups; 3,3,3-trifluoropropyl groups, 2 Examples include halogenated hydrocarbon groups such as-(perfluorobutyl) ethyl group, 2- (perfluorooctyl) ethyl group, and p-chlorophenyl group. In the present invention, methyl group, phenyl group, and carbon number are particularly preferable. 6 to 14 alkyl groups are preferable, and 90% or more is more preferably a methyl group because it is cheaper. It is more preferably a methyl group. The viscosity of the silicone oil useful in the present invention is preferably 50 to 1,000,000 mPa · sec, more preferably 100 to 500,000 mPa · sec, from the viewpoint of performance and handling. . When the viscosity is less than 50 mPa · s, lubricity may be insufficient. When the viscosity exceeds 1000000 mPa · s, the viscosity is too high and handling becomes difficult, or mixing into the system becomes difficult. There is. One or two or more different silicone oils can be used in combination.

  0.1-40 mass% is preferable and, as for the ratio of the said (A) component in the lubricant composition for belt conveyors of this invention, it is more preferable that it is 0.1-20 mass%. If it is less than 0.1% by mass, sufficient lubricity may not be obtained, and if it exceeds 40% by mass, storage stability may not be obtained.

Any nonionic emulsifier can be used as the nonionic emulsifier whose component HLB is 16 or more. Specific examples include polyoxyalkylene lauryl ether, polyoxyalkylene myristyl ether, polyoxyalkylene oleyl ether, polyoxyalkylene stearyl ether, polyoxyalkylene distearyl ether, polyoxyalkylene styrenated phenyl ether, polyoxyalkylene didecyl ether, Examples include polyoxyalkylene isodecyl ether, polyoxyalkylene coconut alcohol ether, polyoxyalkylene glyceryl isostearate, polyoxyalkylene glycol oleyl ether, polyoxyalkylene coconut fatty acid sorbitan and the like. As a nonionic emulsifier of (B) component, since the compatibility with PET bottles containing carbonated beverages and storage stability become better, those having an HLB of 16.0 to 19.5 are preferable, and HLB 16.0 to 19. More preferred is 0. In addition, polyoxyalkylene shows the random or block polymer of polyoxyethylene, polyoxypropylene, polyoxyethylene, and polyoxypropylene. You may combine the nonionic emulsifier whose 2 or more types of HLB is 16 or more. As the nonionic emulsifier, polyoxyethylene glyceryl isostearate, polyoxyethylene glycol oleyl ether, and polyoxyethylene coconut fatty acid sorbitan are preferable because the lubricating film has excellent water resistance. These may be used alone or in combination of two or more. Nonionic emulsifier in the above-mentioned component (B) relative to component (A) 1 part by weight, but is 0.1-0.5 parts by mass, it is formulated 0.1-0.4 parts by weight It is more preferable that 0.2 to 0.3 parts by mass is blended. If the amount is less than 0.05 parts by weight, sufficient storage stability may not be obtained. If the amount exceeds 0.5 parts by weight, the water resistance of the lubricating film is reduced and compatibility with PET bottles containing carbonated beverages is reduced. May get worse.

  In the lubricant composition for a belt conveyor of the present invention, examples of the polyol (C) include glycerin, sorbitol, and polyethylene glycol represented by the following general formula (2). These polyols can be used alone or in combination of two or more.

(Chemical formula 2)
_{H- (OC 2 H 4) m} -OH (2)
(In the formula, m represents a number of 3 to 1000.)

  Polyethylene glycol having a molecular weight of 3 to 1000 can be used as the polyethylene glycol, but from the viewpoint of good lubricity and sprayability, the value of m is preferably 3 to 500, more preferably 3 to 100, 3 to 50 is more preferable, and 3 to 10 is most preferable. When the value of m is less than 3, good lubricity cannot be obtained, and when the value of m is more than 1000, the viscosity when dissolved in water increases, making it difficult to handle or spraying during use. Etc. may not work well. Further, glycerin is most preferable from the viewpoint of lubricity after drying. These may be used alone or in combination of two or more.

  The polyol of the component (C) is blended in the range of 0.0125 to 900 parts by weight with respect to 1 part by weight of the component (A), more preferably in the range of 0.025 to 500 parts by weight. It is most preferable to blend in the range of 0.05 to 300 parts by mass. If it is less than 0.0125 parts by mass, the storage stability may be insufficient, and if it exceeds 900 parts by mass, the lubricity may be deteriorated.

  The lubricant composition for a belt conveyor of the present invention contains components that are usually used in the technical field according to the formulation form of the lubricant composition for a belt conveyor as long as the effects of the present invention are not impaired. Also good. Examples of such components include bactericides, metal corrosion inhibitors, chelating agents, pH adjusters, thickeners, fragrances, and pigments.

  Examples of the bactericides include cationic surfactants, amphoteric surfactants, thiazolines, hydantoins, iodo-2-propynylbutyl carbamate, isopropylmethylphenol, hexachlorophene, irgasan, triclosan, alcohols, and the like. Of these components, more preferred are thiazolines, hydantoins, iodo-2-propynylbutyl carbamate, and isopropylmethylphenol. These may be used alone or in combination of two or more.

  Examples of the cationic surfactant used as the disinfectant include benzethonium chloride, benzalkonium chloride, didecyldimethylammonium salt, dioctyldimethylammonium salt, decylisononyldimethylammonium salt, didecylmethylpolyoxyethyleneammonium salt, Alkylbenzylimidazolium salt, alkyldimethylbenzylammonium salt, alkyldimethylethylbenzylammonium salt, alkyldimethylmethylbenzylammonium salt, cetylpyridinium chloride, trialkylamine salt, alkyltriamine salt, polyhexamethylene biguanide hydrochloride, chlorhexidine gluconate, Chlorhexidine hydrochloride, 1,4-bis (3,3 ′-(1decylpyridinium) methyloxy) butane dibromide It is. Examples of amphoteric surfactants include sodium lauryl diaminoethyl glycine, alkyl diaminoethyl glycine hydrochloride, and alkyl polyaminoethyl glycine hydrochloride. Thiazolines include 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, isothiazoline-3-one, 1,2-benzisothiazolin-3-one, Nn-butyl-benzisothiazolin-3-one and the like. Hydantoins include 1,3-dimethylol-5,5-dimethylhydantoin, 1 or 3-monomethylol-5,5-dimethylhydantoin, dimethylhydantoin, 1,3-dichloro-5,5-dimethylhydantoin, 1, Examples include 3-dichloroethylmethylhydantoin. Examples of alcohols include ethyl alcohol, isopropyl alcohol, n-propyl alcohol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,2-pentanediol and the like.

  Examples of metal corrosion inhibitors include polycarboxylic acids such as short-chain dicarboxylic acids and tricarboxylic acids, phosphate esters, triazoles such as benzotriazole, tolyltriazole and mercaptobenzothiazole, 1-hydroxyethylidene-1,1-diphosphonic acid, etc. Such as phosphonic acid, adipic acid, glutaric acid, and succinic acid.

  Chelating agents include ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), hydroxyethylenediaminetriacetic acid (HEDTA), diethylenetriaminopentaacetic acid (DTPA), triethylenetetraaminehexaacetic acid (TTHA), hydroxyethyliminodiacetic acid. (HIDA), dihydroxyethyl glycine (DHEG), methyl glycine diacetate (MGDA), glutamate diacetate (GLDA), aspartate diacetate (ASDA), β-alanine diacetate (ADA), serine diacetate (SDA), Amino acids such as glycine, alanine, glutamic acid, aspartic acid, glucolic acid, lactic acid, citric acid, gluconic acid, tartaric acid, malic acid and their alkali metal salts, ammonium salts, monoethanolamine, triethanolamine, monoiso Alkanolamine salts such as Ropanoruamin like.

  Examples of the pH adjuster include acetic acid, hydrochloric acid, sulfuric acid, nitric acid, citric acid, phosphoric acid, sodium hydroxide, potassium hydroxide, sodium acetate, sodium carbonate, sodium citrate, sodium hydrogen citrate, sodium phosphate, phosphorus Examples thereof include sodium oxyhydrogen.

  Examples of the thickening agent include alkali neutralized salts of high-molecular polycarboxylic acids such as carboxyvinyl polymer, carboxymethylcellulose, and polyacrylic acid.

  Examples of the fragrances include natural fragrances, synthetic fragrances, and blended fragrances thereof. Examples of the dye include natural dyes, synthetic dyes, and mixtures thereof.

  The lubricant composition for a belt conveyor of the present invention may be applied directly on a belt conveyor or an object to be transported such as a container transported by the belt conveyor. In order to facilitate the work, it is preferable to use a treatment liquid in which the concentration of the component (A) is 0.1 to 5% by mass. When the concentration of component (A) in the lubricant composition is 0.1 to 5% by mass, the lubricant composition can be used as it is, but diluted with water or hot water as necessary. . As for the density | concentration of (A) component in a process liquid, 0.2-2 mass% is more preferable, and it is still more preferable to use in the range of 0.5-1.0 mass%. If the amount of the oily substance (A) is less than 0.1% by mass, sufficient lubricity may not be obtained, and when the amount exceeds 5% by mass, the compatibility with carbonated beverage PET bottles may deteriorate. The lubricant composition on the conveyor may adhere to the bottom of the container and contaminate the container. When diluted with water or hot water and used, it is preferable to adjust the pH to 4 to 10 in order to increase the storage stability. In order to make pH into 4-10, a pH adjuster can be added as needed. As a method for supplying the lubricant composition onto the belt conveyor and / or the object to be transported by the belt conveyor, a method such as spraying, applying, or dripping a solution diluted with a stock solution or water may be employed. However, when supplying onto a belt conveyor, the method of spraying with a spray etc. is suitable. The shape of the spray varies depending on the type of spray nozzle, but it can be used properly according to the application, and any known one can be used, but among them, the holo-cone type, full-cone type, flat spray, fine Use of a spray or the like is preferable. As an example of a method of supplying by spraying, since the amount of lubricant and water used can be reduced, intermittent spraying is performed, spraying is performed at a spraying amount of about 1 to 100 ml / min for about 5 to 300 seconds, and thereafter 10 to 180 minutes For example, the step of stopping spraying to a certain extent may be performed continuously.

  The transported object is not particularly defined as long as it is used on a belt conveyor, but a beverage container is preferable. Examples of the material of such a container include polyethylene terephthalate (PET), polyethylene, polypropylene, Examples include plastic containers such as polystyrene, polyamide, and polycarbonate, paper containers (including wax finish and resin coating), iron, aluminum, tin, copper, zinc, glass containers, and ceramic containers. . Among these containers, use in a PET container, an aluminum container, or a glass container is preferable.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The numerical values in the examples and comparative examples are the mass (%) of the pure component. The components (A), (B) and (C) used in Examples and Comparative Examples are shown below.

(A) Component A-1: Polyalphaolefin (Sinfluid 201, Nippon Steel Chemical)
A-2: Polydimethylsiloxane (KF-96, Shin-Etsu Silicone)
A-3: Liquid paraffin (High Coal K-230, Kaneda)

Component (A) Comparative component [hereinafter referred to as “(A ′) component”] ]
A'-1: Caprylic acid triglyceride (Coconard RK, Kao)
A'-2: oleyl alcohol (oleyl alcohol SS, higher alcohol industry)

(B) Component B-1: Polyoxyethylene isostearate (25 mol) glyceryl (HLB16.1 Neugen GIS125, Daiichi Kogyo Seiyaku)
B-2: Polyethylene (15 mol) glycol oleyl ether (HLB16 NIKKOL BO-15V, Nikko Chemicals)
B-3: Polyoxyethylene (130 mol) beef tallow fatty acid glyceryl (HLB19.1 Unigri MT-2130W, NOF)

Component (B) Comparative component [hereinafter referred to as “component (B ′)”. ]
B′-1: polyoxyethylene isostearate (8 mol) glyceryl (HLB12.1 Neugen GIS108, Daiichi Kogyo Seiyaku)
B′-2: Polyoxyethylene monostearate (20 mol) sorbitan (HLB15 NIKKOL TO-10V, Nikko Chemicals)
B′-3: Polyethylene (2 mol) glycol oleyl ether (HLB7.5 NIKKOL BO-2V, Nikko Chemicals)

(C) Component C-1: Glycerin (Kashima Chemical)
C-2: Polyethylene glycol (PEG200, Sanyo Chemical Industries)
C-3: Sorbitol (Sorbit T-70, Towa Kasei)

Component (C) Comparative component [hereinafter referred to as “component (C ′)”. ]
C′-1: Ethanol C′-2: Normal propyl alcohol

Examples 1 to 20 , Reference Examples 1 to 8, Comparative Examples 1 to 22
Lubricant compositions were prepared based on the formulations shown in Tables 1-5. The composition of the example and the composition of the comparative example were each prepared so that a stable emulsion could be obtained according to the difference in formulation. A method for preparing the lubricant composition of the example and the lubricant composition of the comparative example is shown below. The result of having measured the storage stability of each obtained lubricant composition, lubricity, and a PET bottle containing carbonated drink by the method shown below is shown according to Tables 1-5.

Sample Preparation Method Using a stirrer MAZELA Z-1000 (manufactured by Tokyo Rika Kikai Co., Ltd.) under a temperature condition of 50 ° C., a polyol in the range of 0.25 to 2 parts relative to 1 part of emulsifier, and 0.1 part of emulsifier Part to 1.5 parts of water were mixed and stirred at a rotation speed of 100 rpm to obtain a uniform solution. Next, the oil component was added while continuing stirring, and after adding the entire amount of the oil component, the mixture was stirred for 1 hour at a rotation speed of 400 rpm. Thereafter, the remaining polyol and water were added, and the mixture was stirred for 10 minutes at a rotation speed of 100 rpm to prepare a lubricant composed of an oil-in-water emulsion.

Storage stability test method:
100 g of the prepared lubricant composition was put in a transparent glass bottle and allowed to stand at 40 ° C. for 1 month, and then the appearance was observed to evaluate the storage stability.
Storage stability evaluation criteria:
○: Oil phase and water phase are not separated and stable.
Δ: There is no overall separation, but an oil film is seen on the surface.
X: The aqueous phase is separated at the bottom by creaming (the dispersed oil phase droplets rise and become non-uniform).
And Δ and ○ were determined to be practical.

Lubricity test method:
Place a container made of polyethylene terephthalate (PET) with a square bottom and a volume of 900 ml, use a stock solution of the lubricant composition as a treatment liquid on a resin conveyor of a belt conveyor speed of 30 m / min. A coefficient (immediately after adhesion), a friction coefficient at the time of drying 15 minutes after spraying (after drying), and a coefficient of friction (after water washing) after washing with water at a supply rate of 60 ml / min for 10 minutes were measured. The friction coefficient is calculated from the following calculation formula by connecting the container and the load measuring device, measuring the tensile load value during the operation of the conveyor.
Coefficient of friction (μ) = tensile load (g) / container weight (g)
Lubricity evaluation method:
○: Friction coefficient (μ) = 0.7 or more and less than 0.10 (slip is good)
Δ: Friction coefficient (μ) = 0.10 or more and less than 0.12 (slip without problems)
×: Friction coefficient (μ) = 0.12 or more (slippery)
And Δ and ○ were determined to be practical.

Test method for PET bottle compatibility test with carbonated drink:
A commercially available PET bottle containing 500 ml of cola drink and 10 g of lubricant were brought into contact with each other in a beaker and stored at 40 ° C. and a humidity of 90% for 1 week, and then the state of crazing on the bottom of the bottle was observed.
PET bottle compatibility evaluation method with carbonated drink:
○: No crazing has occurred.
(Triangle | delta): Crazing has generate | occur | produced slightly.
X: Innumerable crazing has occurred.
And Δ and ○ were determined to be practical.

  As described above, the lubricant composition for belt conveyors of the present invention is excellent in storage stability, stress cracking property of PET bottles containing carbonated beverages, excellent in water resistance of lubricating films formed on containers and belt conveyors, and scattered. Even when the water is used, the lubricity is not lowered and the lubricity can be maintained.

Claims (3)

As component (A), it contains at least one oily substance selected from silicone oil, polyalphaolefin, liquid paraffin, and (A) 1 part by mass of component,
As the component (B), and a non-ionic emulsifier HLB is 16 or more 0.1-0.5 parts by weight
(C) As a component, 0.0125-900 mass parts of polyols,
A lubricant composition for a belt conveyor, which is an oil-in-water emulsion containing   The lubricant composition for a belt conveyor according to claim 1, wherein the polyol of the component (C) is at least one selected from glycerin, polyethylene glycol, and sorbitol.   The processing liquid having a component (A) concentration of 0.1 to 5% by mass in the belt conveyor lubricant composition according to claim 1 or 2 is supplied to a belt conveyor that conveys containers to impart lubricity. A lubricating method for a belt conveyor.