JP2013194092A - Cleaning liquid composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning liquid composition which can be used in a step of cleaning an apparatus for mixing an isocyanate component with a polyol component to produce a urethane resin, and which can satisfy cleaning property, drying property and safety.SOLUTION: A cleaning liquid composition which is used in the step of cleaning an apparatus for mixing an isocyanate component with a polyol component to produce a urethane resin, contains 1-4C straight-chain or branched-chain alcohol, a lactic ester formed from lactic acid, and water. The mixing ratio of (the lactic ester)/(the water) is 87/13 to 60/40 by a mass ratio.

Description

  The present invention relates to a cleaning liquid composition used in a cleaning process of an apparatus for producing a urethane resin by mixing an isocyanate component and a polyol component.

As an example of a method for producing a two-component mixed urethane resin produced by mixing an isocyanate component and a polyol component, there is a method in which an isocyanate component and a polyol component are mixed and foamed inside a production apparatus.
In the manufacturing apparatus used in this method, the polyol component and the isocyanate component are mixed and stirred, the resin is cast, and then the unreacted isocyanate component adhering to the manufacturing apparatus before the residue remaining inside the apparatus is completely cured. It is necessary to wash the unreacted polyol component, the generated urethane component, the catalyst, and the like. Conventionally, in this cleaning process, methylene chloride has been used in consideration of cleaning properties, drying properties, flash point, and the like.

However, in recent years, due to increasing interest in environmental conservation, it is required that volatile organic compounds are not released into the environment by drying the cleaning liquid composition. Therefore, alternative substances for methylene chloride have been proposed (see Patent Document 1 and Patent Document 2).
Patent Document 1 discloses a mold cleaning composition containing a hydroxycarboxylic acid ester and ethylene glycol monoalkyl ether. However, the hydroxycarboxylic acid ester disclosed in the examples of Patent Document 1 is designated as a dangerous material corresponding to the third class of third petroleum under the Fire Service Law, and the ethylene glycol monoalkyl ether is classified as a fourth class of petroleum. It is designated as a hazardous material that falls under Class 4 petroleum.

  Patent Document 2 discloses a cleaning composition containing diethylene glycol diethyl ether and 3-methyl-3-methoxy-1-butanol. However, since these solvents are also designated as the 4th class 3rd petroleums and the 2nd petroleums, sufficient safety measures are required at the time of use.

  On the other hand, water-based cleaning agents and semi-aqueous cleaning agents in which water-soluble solvents are mixed with water-based cleaning agents are not flammable and can be used without taking any special safety measures. However, since the cleaning property is lower than that of the cleaning composition of Patent Document 1 or 2, it is necessary in a large amount and causes another problem such as waste liquid treatment.

  As cleaning agents for urethane resins, amine solvents such as dimethylformamide (DMF) and N-methylpyrrolidone (NMP) capable of swelling urethane resins are known. However, these amine solvents are suitable for swelling and washing of the urethane resin after curing, but have a low washing effect on the urethane resin during the reaction. In addition, since the amine solvent has low drying properties, it is necessary to take sufficient measures to prevent the amine solvent that is the cleaning liquid composition from remaining in the apparatus.

  Thus, in the field | area which manufactures a urethane resin by mixing an isocyanate component and a polyol component, development of the washing | cleaning liquid composition which can satisfy all cleaning property, drying property, and safety | security was calculated | required.

JP 09-003494 A JP 2011-068858 A

  An object of the present invention is to provide a cleaning liquid composition which can be used in a cleaning process of an apparatus for producing a urethane resin by mixing an isocyanate component and a polyol component, and which can satisfy cleaning properties, drying properties and safety. To do.

As a result of intensive studies to achieve the above object, the present inventor has found that a cleaning liquid composition containing a specific lactic acid ester and water in a specific ratio achieves the above object, thereby completing the present invention. It was.
That is, the present invention is a cleaning liquid composition used in a cleaning process of an apparatus for producing a urethane resin by mixing an isocyanate component and a polyol component, and is a linear or branched alcohol having 1 to 4 carbon atoms. The present invention also relates to a cleaning liquid composition comprising a lactic acid ester formed from lactic acid and water, wherein a mixing ratio of the lactic acid ester and the water is 87/13 to 60/40 by mass ratio.

  ADVANTAGE OF THE INVENTION According to this invention, the washing | cleaning liquid composition which can be used in the washing | cleaning process of the apparatus which mixes an isocyanate component and a polyol component and manufactures a urethane resin, and can satisfy detergency, drying property, and safety can be provided. .

Hereinafter, embodiments of the present invention will be described in detail.
[Cleaning liquid composition]
The cleaning liquid composition of the present embodiment is a cleaning liquid composition used in a cleaning process of an apparatus for producing a urethane resin by mixing an isocyanate component and a polyol component, and is linear or branched having 1 to 4 carbon atoms. The lactic acid ester formed from the alcohol and lactic acid in the form of water and water, and the mixing ratio of the lactic acid ester and the water is 87/13 to 60/40 by mass ratio.
If the water ratio is less than 13/100, the flash point of the lactic acid ester cannot be lost, and thus the safety cannot be satisfied, which is not preferable. Moreover, since the detergency falls when the ratio of water exceeds 40/100, it is unpreferable.
From the viewpoint of disappearance of the flash point and maintenance of detergency, the mixing ratio of lactic acid ester and water is preferably 85/15 to 80/20 in terms of mass ratio.
According to the cleaning liquid composition of the present embodiment, since it has solubility in any of the unreacted isocyanate component that is hydrophobic, the unreacted polyol component that is hydrophilic, and the urethane component generated by the reaction, A cleaning effect can be obtained not only on the urethane component produced by the reaction but also on the urethane resin raw material in the middle of the reaction.
Moreover, it is preferable that the temperature conditions of washing | cleaning performed using the washing | cleaning liquid composition of this invention are higher than normal temperature (25 degreeC). Since the curing reaction of the urethane component is accelerated when the temperature exceeds 50 ° C., when the temperature condition of the cleaning liquid composition exceeds 50 ° C., the urethane component starts to be cured before the cleaning is completed, and a residue tends to remain. For this reason, it is preferable that the temperature conditions of a washing | cleaning liquid composition are 30-50 degreeC, More preferably, it is 40-50 degreeC.
Moreover, it is preferable that the pH of the washing | cleaning liquid composition is adjusted to 3-7 from a viewpoint of improving the washability with respect to a urethane component.

[Lactic acid ester]
As the lactic acid ester, a lactic acid ester formed from a linear or branched alcohol having 1 to 4 carbon atoms and lactic acid can be used.
As the lactic acid ester, a lactic acid ester having a solubility parameter close to that of the urethane component is preferably used, and at least one selected from ethyl lactate, methyl lactate, propyl lactate and butyl lactate can be used. Among these, it is preferable to use ethyl lactate.
Ethyl lactate has a flash point of 53 ° C., and is classified as a hazardous material class 4 and class 2 petroleum under the Fire Service Law. Ethyl lactate has water solubility, and its flash point disappears when diluted with water. Therefore, by using it diluted, the safety in the washing process can be improved.
In addition, the solubility parameter (SP value) of ethyl lactate is around 10, which is close to the urethane component and can sufficiently wash the urethane component after the reaction.
Ethyl lactate may be an artificially synthesized product synthesized industrially, or may be a naturally derived one extracted from soybeans or the like.

[water]
Usually, it was found that the isocyanate component hardly dissolves in ion-exchanged water, distilled water, tap water or the like, but slightly dissolves in electrolytic water such as alkaline electrolyzed water. Accordingly, ion-exchanged water, distilled water, tap water, or the like can be used as water, and alkaline electrolyzed water is preferably used. Examples of the alkaline electrolyzed water include alkaline electrolyzed water adjusted with potassium hydroxide and alkaline electrolyzed water adjusted with sodium metasilicate.

[Urethane resin]
The urethane resin is obtained by reacting a polyol and a polyisocyanate in the presence of a catalyst and, if necessary, a foaming agent, a surfactant, a crosslinking agent, and the like. Examples of the urethane resin include a flexible polyurethane foam, a semi-rigid polyurethane foam, a rigid polyurethane foam manufactured using a foaming agent, and an elastomer product that does not use a foaming agent.

<Polyol component>
As the polyol component that can be used for the production of the urethane resin, conventionally known polyether polyols, polyester polyols, polymer polyols, and flame retardant polyols such as phosphorus-containing polyols and halogen-containing polyols can be used. These polyols can be used alone or in combination.

As the polyether polyol, a compound having at least two active hydrogen groups is used as a starting material, and an addition reaction between the compound and an alkylene oxide typified by ethylene oxide or propylene oxide, for example, Gunter Oertel, “Polyurethane Handbook” ( (1985 edition) Hanser Publishers (Germany), pages 42-53.
Examples of the starting material include polyhydric alcohols, amines, alkanolamines, etc. Examples include water, propylene glycol, ethylene glycol, glycerin, trimethylolpropane, hexanetriol, triethanolamine, diglycerin. , Pentaerythritol, ethylenediamine, methyl glucotite, aromatic diamine, sorbitol, sucrose, phosphoric acid and the like as starting materials, and those obtained by addition polymerization of ethylene oxide and propylene oxide.

  Polyester polyols include reaction products of dibasic acids and glycols, wastes from the production of nylon, trimethylolpropane, pentaerythritol wastes, phthalic polyester wastes, polyester polyols derived from processing wastes, etc. Keiji's “Polyurethane Resin Handbook” (first published in 1987), published by Nikkan Kogyo Shimbun, page 117.

  Examples of the polymer polyol include a polymer polyol obtained by reacting the above-described polyether polyol and an ethylenically unsaturated monomer such as butadiene, acrylonitrile, styrene, etc. in the presence of a radical polymerization catalyst.

Examples of the flame retardant polyol include phosphorus-containing polyols obtained by adding alkylene oxide to a phosphoric acid compound, halogen-containing polyols obtained by ring-opening polymerization of epichlorohydrin and trichlorobutylene oxide, and phenol polyols.
The molecular weight (Mw) of these polyols is 62 to 15000. When manufacturing a flexible polyurethane foam, it is preferable that the molecular weight (Mw) of the polyol to be used is 1000-15000. Moreover, it is preferable that they are a polyether polyol and polymer polyol whose molecular weight (Mw) is 3000-15000. When the molecular weight is smaller than 3000, the physical properties (elasticity) and the like may be inferior, and therefore, a molecular weight of 3000 or more is desired.

<Isocyanate component>
The isocyanate component used in the production of the urethane resin may be a conventionally known isocyanate component, for example, aromatic polyisocyanate such as toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthylene diisocyanate, xylylene diisocyanate, Aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as dicyclohexyl diisocyanate and isophorone diisocyanate, and mixtures thereof. Examples of TDI and derivatives thereof include a mixture of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate or a terminal isocyanate prepolymer derivative of TDI. Examples of MDI and its derivatives include a mixture of MDI and its polymer polyphenyl-polymethylene diisocyanate and / or a diphenylmethane diisocyanate derivative having a terminal isocyanate group. Of these polyisocyanates, TDI and MDI are preferably used.

<Ratio of polyisocyanate and polyol>
The ratio of the polyisocyanate and the polyol is not particularly limited, but in the production of flexible polyurethane foam and semi-rigid polyurethane foam, it is in the range of 60 to 130 in terms of isocyanate index (isocyanate group / active hydrogen group capable of reacting with isocyanate group). In the production of rigid polyurethane foam and urethane elastomer, it is generally preferably in the range of 60 to 400.

<Catalyst>
As the catalyst used in the method for producing a polyurethane resin, conventionally known organometallic catalysts, tertiary amines, quaternary ammonium salts, and the like can be used without departing from the effects of the present invention.
Examples of the organometallic catalyst include stannous diacetate, stannous dioctoate, stannous dioleate, stannous dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, dioctyltin dilaurate, and lead octoate. , Lead naphthenate, nickel naphthenate, cobalt naphthenate and the like.

  The tertiary amines may be any conventionally known ones such as N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetramethylpropylenediamine, N, N, N ′, N ″, N ″ -pentamethyldiethylenetriamine, N, N, N ′, N ″, N ″ -pentamethyl- (3-aminopropyl) ethylenediamine, N, N, N ′, N ″, N ″ Pentamethyldipropylenetriamine, N, N, N ′, N′-tetramethylguanidine, 1,3,5-tris (N, N-dimethylaminopropyl) hexahydro-S-triazine, 1,8-diazabicyclo [5 4.0] undecene-7, triethylenediamine, N, N, N ′, N′-tetramethylhexamethylenediamine, N-methyl-N ′-(2-dimethylaminoethyl) Perazine, N, N′-dimethylpiperazine, dimethylcyclohexylamine, N-methylmorpholine, N-ethylmorpholine, bis (2-dimethylaminoethyl) ether, 1-methylimidazole, 1,2-dimethylimidazole, 1-isobutyl- And tertiary amine compounds such as 2-methylimidazole and 1-dimethylaminopropylimidazole.

  Further, tertiary amine compounds having reactive groups other than those of the present invention can also be used, for example, dimethylethanolamine, dimethylisopropanolamine, N, N-dimethylhexanolamine, dimethylaminoethoxyethanol, N, N-dimethyl-N. '-(2-hydroxyethyl) ethylenediamine, N, N-dimethyl-N'-(2-hydroxyethyl) propanediamine, N-methyl-N '-(2-hydroxyethyl) piperazine, bis (dimethylaminopropyl) amine , Bis (dimethylaminopropyl) isopropanolamine, 1- (2-hydroxyethyl) imidazole, 1- (2-hydroxypropyl) imidazole, 1- (2-hydroxyethyl) -2-methylimidazole, 1- (2-hydroxy Propyl) -2-methylimidazo Le, 3-quinuclidinol, and the like.

  As quaternary ammonium salts, conventionally known tetraalkylammonium halides such as tetramethylammonium chloride, tetraalkylammonium hydroxides such as tetramethylammonium hydroxide, tetramethylammonium 2-ethylhexanoate, 2 -Tetraalkylammonium organic acid salts such as hydroxypropyltrimethylammonium formate and 2-hydroxypropyltrimethylammonium 2-ethylhexanoate.

<Foaming agent>
You may mix | blend a foaming agent with the resin raw material of a urethane resin. Examples of the foaming agent include water and low-boiling organic compounds. The low boiling point organic compound is a hydrocarbon-based or halogenated hydrocarbon-based compound. As the hydrocarbon compound, conventionally known methane, ethane, propane, butane, pentane, hexane and the like can be used. As the halogenated hydrocarbon compound, conventionally known halogenated methane, halogenated ethanes, fluorinated hydrocarbons can be used, and specifically, methylene chloride, HCFC-141b, HFC-245fa, HFC-356mfc, etc. Can be used. In the use of these foaming agents, water and a low-boiling organic compound may be used alone or in combination, respectively, but water is a particularly preferable foaming agent in terms of environment. The amount used may vary depending on the density of the target product, but is usually 0.1 parts by mass or more, preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the polyol.

<Surfactant>
In producing the urethane resin, a surfactant can be used if necessary. As a surfactant, it is a conventionally well-known organic silicone type surfactant, The usage-amount is 0.1-10 mass parts with respect to 100 mass parts of polyols.

<Crosslinking agent and chain extender>
When manufacturing a urethane resin, if necessary, a crosslinking agent or a chain extender can be added. Examples of the crosslinking agent or chain extender include low molecular weight polyhydric alcohols (eg, ethylene glycol, 1,4-butanediol, glycerin, etc.), low molecular weight amine polyols (eg, diethanolamine, triethanolamine, etc.), low molecular weights. Polyamines (for example, ethylenediamine, xylylenediamine, methylenebisorthochloroaniline, etc.). Of these, diethanolamine and triethanolamine are preferred.

<Other additives>
In the present invention, a colorant, a flame retardant, an anti-aging agent, and other known additives can be used as necessary. The types and amounts of these additives can be used within the range normally used without departing from the known formats and procedures.

[Production method of urethane foam]
The urethane foam can be produced by an addition polymerization method in the presence of the above-described components. In this production method, the resin material is agitated by a stirring type in-line mixer installed in a line for supplying a resin material containing an isocyanate component, a polyol component, and an additive such as a catalyst and / or a line for transferring between reaction vessels. To cause foaming (foaming step). After this foaming step, the cleaning liquid composition is put into an in-line mixer and the cleaning step is performed.
Subsequently, in the drying step, the inside of the inline mixer is heated, or a heated gas is blown into the inside of the inline mixer to dry the cleaning liquid composition adhering to the inside of the inline mixer. The period required for the drying step can be adjusted by appropriately setting heating conditions, gas blowing conditions, and the like.
After the drying step, the isocyanate component and the polyol component are again put into the container, and the foaming step and subsequent steps are repeatedly executed.
According to the cleaning liquid composition of the present embodiment, the inside of the in-line mixer can be suitably cleaned.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.
[Evaluation method]
<Detergency>
Isocyanate containing diphenylmethane diisocyanate and its derivatives as isocyanate component, weight average molecular weight 100-1000 as polyol component, rigid urethane foam formed by premixing additives such as foam stabilizer, catalyst, flame retardant, filler, etc. did. This rigid urethane foam had a cream time of 6 seconds, a gel time of 43 seconds, a rise time of 65 seconds, and a free foam density (SG) of 90 kg / m ³ .
Here, cream time represents a period until foaming starts, gel time represents a period during which the two liquids are cured (resinized), and rise time represents a period until foaming is completed. .
(1) Preparation of cleaning liquid composition 150 g of the cleaning liquid composition shown in Table 1 was prepared in a 300 cc cup.
(2) Preparation of urethane resin raw material The polyol component and the isocyanate component are weighed, and the polyol component / isocyanate component = 30 g / 30 g is put into a 300 cc cup together with other additives in a mass ratio for 3 seconds (cream time (foaming start ) Stirring was carried out and the rotation of the stirring blade was stopped. After confirming that foaming started, the stirring blade was taken out of the cup containing the reaction product. At this time, the urethane resin raw material is attached to the stirring blade, and the expansion of the attached urethane resin raw material proceeds in the order of cream time, gel time, and rise time with time.
(3) Washing of stirring blade Soak the stirring blade with the urethane resin raw material attached in the cleaning liquid composition prepared in (1). While gently rotating the cup by hand, immerse the stirring blade for 10 seconds, remove the cleaning liquid cup, The degree of dirt on the stirring blade was confirmed visually. The above-described cleaning test was performed for each of a plurality of stirring blades having different elapsed times from the start of stirring.
-15 seconds have elapsed since the start of stirring (after cream time)
・ 30 seconds have passed since the start of stirring (before gel time)
・ 60 seconds have passed since the start of stirring (before rise time)
・ 90 seconds have passed since the start of stirring (after rise time)
The detergency was expressed by an index of 1 to 5 as follows, and 3 or more was judged as good. The results are shown in Table 1.
A residue of 10% or more of reaction product remains after 15 seconds from the start of stirring: 1
-90% or more of the reaction product after 15 seconds from the start of stirring can be dissolved: 2
-90% or more of the reaction product after 30 seconds from the start of stirring can be dissolved: 3
The reaction product after 60 seconds from the start of stirring can be dissolved by 90% or more: 4
90% or more of the reaction product after 90 seconds from the start of stirring can be dissolved to 90% or more: 5

<Drying>
The drying property of the cleaning liquid composition was evaluated as follows.
(1) 10 g of each of the cleaning liquid compositions of Examples, Comparative Examples, and Reference Examples was collected in a petri dish.
(2) The petri dish containing the cleaning liquid composition was placed on a plate heated to 40 ° C., the mass was measured at predetermined intervals, and the period until the mass of the petri dish alone was measured.
The drying property was expressed by an index of 1 to 5 as follows based on time, and 2 or more was judged as good. The results are shown in Table 1.
-6 hours or more from the start of heating: 1
-Within 6 hours from the start of heating: 2
-Within 4 hours from the start of heating: 3
-Within 2 hours from the start of heating: 4
・ Can be dried within 1 hour at room temperature without heating: 5

<Flash point>
The flash point was represented by an index of 1 to 5 based on the classification under the Fire Service Law, and 5 was judged as good. The results are shown in Table 1.
・ Corresponds to Class 4 and Class 2 Petroleum: 1
・ Corresponds to Class 4 and Class 3 petroleum non-water soluble: 2
・ Corresponds to Class 4 and Class 3 petroleum water solubility: 3
・ Category 4 and 4: 4
・ Applies to non-dangerous goods: 5

[Examples and Comparative Examples]
<Examples 1-7, Comparative Examples 1-9>
Cleaning liquid compositions were prepared at the blending ratios shown in Table 1. As a reference example, a conventional general-purpose halogen solvent was used.

[Note] In Table 1,
* 1: Tap water * 2: Alkaline electrolyzed water manufactured by Toshin Oil Chemical Co., Ltd., trade name “ECO Clean Water”
* 3: Ethyl lactate made by Musashino Chemical Laboratory * 4: Methyl lactate made by Musashino Chemical Laboratory * 5: Butyl lactate made by Musashino Chemical Laboratory * 6: Alcohol hydrocarbon made by Denso Corp. Product name "HC-AW7000"
* 7: N-methylpyrrolidone BASF brand name “NMP”
* 8: Ethanol * 9: Product name "Elise M9021" manufactured by Asahi Kasei Chemicals Corporation
* 10: Product name “Neo River # 1412” manufactured by Sansai Kaiko Co., Ltd.
* 11: Methylene chloride * 12: n-propyl bromide ALBEMARLE brand name "ABZOL JE-100"

[Evaluation results]
According to the cleaning liquid compositions of Examples 1 to 7, the cleaning properties are excellent, and since there is no flash point and it corresponds to a non-hazardous material, it can be seen that the safety is also good. Further, there is no difference in cleaning properties when compared with the cleaning liquid compositions of Examples 1 and 2, but when compared with the cleaning liquid compositions of Examples 4 and 5, alkaline electrolysis water is used as the water when the amount of water is increased. It can be seen that the use of can improve the cleanability.

Claims (3)

A cleaning liquid composition used in a cleaning process of an apparatus for producing a urethane resin by mixing an isocyanate component and a polyol component,
A lactic acid ester formed from a linear or branched alcohol having 1 to 4 carbon atoms and lactic acid, and water,
A cleaning liquid composition in which a mixing ratio of the lactic acid ester and the water is 87/13 to 60/40 by mass ratio.   The cleaning liquid composition according to claim 1, wherein a mixing ratio of the lactic acid ester and water is 85/15 to 80/20 by mass ratio.   The cleaning liquid composition according to claim 1 or 2, wherein the lactic acid ester is at least one selected from ethyl lactate, methyl lactate, propyl lactate and butyl lactate.