JP2005162780A - Detergent composition and detergent for liquid crystal cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a detergent for a liquid crystal cell which exhibits excellent performances in cleaning/removing liquid crystals deposited to the liquid crystal cell, costs low and is highly safe. <P>SOLUTION: The detergent for the liquid crystal cell comprises an aqueous dispersion prepared by mixing a component (a) comprising a polyoxyethylene monostyrylphenyl ether (the amount of added ethylene oxide being 5 mole) with a component (b) comprising a polyoxyethylene isodecyl ether (the amount of added ethylene oxide being 6 mole) in a weight ratio of 1:2 and adding ion-exchanged water to the resultant mixture to adjust its concentration to 0.5 wt% in the water. The detergent for the liquid crystal cell is a nonionic detergent that exhibits excellent performances in cleaning/removing remaining liquid crystals deposited to electrode portions of the liquid crystal cell and is low corrosive. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cleaning composition and the like, and more particularly to a cleaning composition suitable for cleaning a liquid crystal cell and the like in a manufacturing process of a liquid crystal cell.

In a liquid crystal cell, a pair of glass substrates on which electrodes and an alignment film are formed are usually bonded together, liquid crystal is injected, sealed with a sealant, and then the liquid crystal adhering to the gap between the glass substrates is washed and removed to deflect Manufactured by sticking plates. The reason why the liquid crystal is removed by this cleaning process is that the residue of the liquid crystal acts as a mold release agent. Therefore, in the subsequent process, the deflection plate is peeled off, the driver terminal is not connected properly, the driver underfill interface is defective, the substrate is thin This is to prevent various troubles such as peeling of the peelable coating film used in the chemical method.
In general, liquid crystal molecules, which are polarizing compounds, are known to be difficult to disperse or dissolve in aqueous systems due to strong intermolecular interactions and strong hydrophobicity. For this reason, in order to clean and remove the liquid crystal adhering to the liquid crystal cell, the mainstream is to use a cleaning agent to which an ionic activator, an ionic builder, an ionic emulsifier or the like is added. Examples of such a cleaning agent include a cleaning agent containing a chelating agent and an alkaline substance (Patent Document 1), and a cleaning agent containing a salt composed of an ammonium cation and a phosphate ester anion (Patent Document 2). Moreover, the combination with the chelating agent and surfactant which consist of a catechin concentrate, the combination of an ethylenediamine type | system | group chelating agent, surfactant, and a sulfonate is used.

Japanese Patent Laid-Open No. 03-070800 JP 2000-313899 A

By the way, the cleaning agent conventionally used for cleaning and removing the liquid crystal adhering to the liquid crystal cell contains an ionic substance, and also includes a hygroscopic substance as one of the components. For this reason, when a part of these cleaning agents remains in the terminal portion of the liquid crystal cell, there is a problem that it often causes electromigration at the time of liquid crystal driving by ion migration or adsorbed water.
Further, instead of the ionic substance, some nonpolar or polar solvents such as a halogen-based solvent, tetrahydrofuran or acetone can be considered. However, these have problems in terms of flash point, safety, environmental problems, necessity of explosion-proof specifications, and the like, and are practically difficult to use.

The present invention has been made in order to solve the technical problem of the liquid crystal cell cleaning agent conventionally used for cleaning and removing the liquid crystal adhering to the liquid crystal cell.
That is, an object of the present invention is to provide a non-ionic detergent composition having high detergency and low corrosivity.
Another object of the present invention is to provide a cleaning agent for a liquid crystal cell which is excellent in ability to clean and remove liquid crystal adhering to the liquid crystal cell, and which is low in cost and high in safety.

For this purpose, the detergent composition to which the present invention is applied comprises (a) 20% to 60% by weight of polyoxyalkylene styryl phenyl ether and (b) 40% to 80% by weight of polyoxyalkylene alkyl ether. % (However, the sum of (a) and (b) is 100% by weight).
Since the detergent composition to which the present invention having such a configuration is applied has high solubility in liquid crystals and is nonionic, there is a problem due to ion migration and electromigration during liquid crystal driving with adsorbed water. It will be resolved.
The weight ratio of the two components contained in the detergent composition to which the present invention is applied is (a) 30% to 50% by weight of polyoxyalkylene styryl phenyl ether, and (b) polyoxyalkylene alkyl ether It is preferably 50% by weight to 70% by weight.

Here, the polyoxyalkylene styryl phenyl ether as the component (a) can be easily obtained by using a known synthesis method if it is a polyalkylene oxide adduct of styrenated phenol. In particular, (a) polyoxyalkylene styryl phenyl ether is preferably an addition polymer of styrenated phenol and alkylene oxide having 2 to 4 carbon atoms. At this time, (a) polyoxyalkylene styryl phenyl ether is preferably an addition polymer of 1 mol of styrenated phenol and 4 mol to 5 mol of alkylene oxide having 2 to 4 carbon atoms. Thus, by setting the addition amount of alkylene oxide to about 4 to 5 mol, the molecular polarity of polyoxyalkylene styryl phenyl ether is weakened, while the solubility in liquid crystal can be enhanced.
In addition, styrenated phenols usually exist in mono-, di-, and tri-forms, but if the purity of monostyrenated phenol in styrenated phenol is 85% or more, ion migration and adsorption The influence of electromigration when driving liquid crystal with water can be greatly reduced. Among them, (a) polyoxyalkylene styryl phenyl ether is preferably an addition polymer of 1 mol of monostyrenated phenol and 5 mol of ethylene oxide.

In addition, the polyoxyalkylene alkyl ether as component (b) has a linear or branched alkyl group having 4 to 18 carbon atoms, and is a cleaning composition to which the present invention is applied. It is possible to drastically increase the solubility in water, and it is possible to prepare an aqueous detergent that can be used in the form of an aqueous dispersion.
Here, in (b) polyoxyalkylene alkyl ether, it is preferable that the addition mole number of C2-C4 alkylene oxide is 1-10, and especially the addition mole of C2-C3 alkylene oxide. The number is preferably 6. Furthermore, the (b) polyoxyalkylene alkyl ether preferably has an isodecyl group.

By the way, the present invention provides a mixture of (a) 20% to 60% by weight of polyoxyalkylene styryl phenyl ether and (b) 40% to 80% by weight of polyoxyalkylene alkyl ether (provided that (a) and (b )), And 1 g of a mixture having such a composition ratio, and (c) 100 g to 1000 g of water is contained as a cleaning agent for a liquid crystal cell. The liquid crystal cell cleaning agent is characterized by excellent performance in cleaning and removing liquid crystal adhering to the liquid crystal cell.
Here, (c) water is preferably ion-exchanged water.
The cleaning agent for liquid crystal cell to which the present invention is applied does not contain an ionic component, and further, by using it in the form of an aqueous dispersion having a low concentration of about 0.1% by weight, the liquid crystal per liter of the aqueous dispersion It has excellent performance to completely dissolve 5 g. Further, the liquid crystal washed and removed from the liquid crystal cell is stably dispersed in the liquid of the cleaning agent without reattaching to the liquid crystal cell, and can be completely removed by washing with water.

  According to the present invention, a nonionic detergent composition having high detergency and low corrosivity is provided.

Hereinafter, the best mode for carrying out the present invention (hereinafter referred to as an embodiment of the present invention) will be described in detail.
The (a) polyoxyalkylene styryl phenyl ether used in the cleaning composition to which the present embodiment is applied is obtained as a polyalkylene oxide adduct of styrenated phenol.
Here, the synthesis method of the styrenated phenol is not particularly limited, and a known method can be used. For example, it can be produced by a Friedel-Crafts reaction between phenols and styrenes. Examples of phenols include phenol, alkylphenol, arylphenol, and aralkylphenol. Examples of the alkylphenol include cresol, butylphenol, octylphenol, and the like. Examples of the arylphenol include phenylphenol, biphenylphenol, naphthylphenol, and the like. Examples of aralkylphenol include benzylphenol and phenylethylphenol. Among these, phenol, cresol, and phenylphenol are preferable.
Examples of styrenes include styrene, α-methylstyrene, and vinyl toluene. Among these, styrene is preferable.

The reaction conditions for the Friedel-Crafts reaction are not particularly limited. For example, the reaction can be performed by reacting phenols and styrenes at a temperature of 110 to 140 ° C. in the presence of a catalyst.
Incidentally, styrenated phenols usually have mono-, di-, and tri-forms in which styrenes are added to the benzene nuclei of phenols. Among them, a mono-form in which 1 mol of styrene is added to a benzene nucleus of phenol is preferable. The concentration of monostyrenated phenol in styrenated phenol is usually 85% or higher, preferably 90% or higher, more preferably 98 or higher.

  The polyalkylene oxide adduct of styrenated phenol can be produced by addition reaction of alkylene oxide with styrenated phenol. The alkylene oxide is preferably one having 2 to 4 carbon atoms. Among the alkylene oxides, ethylene oxide having 2 carbon atoms and propylene oxide having 3 carbon atoms are preferable, and ethylene oxide is particularly preferable. From the viewpoint of solubility in the liquid crystal, the number of moles of alkylene oxide added is usually 1 mol to 10 mol, preferably 2 mol to 6 mol, and particularly preferably 4 mol to 5 mol. Of these, the most preferable is an adduct of 1 mol of monostyrenated phenol and 5 mol of ethylene oxide. The conditions for the addition reaction are not particularly limited. For example, the addition reaction can be performed at a temperature of 100 ° C. to 190 ° C.

  A preferable embodiment of (a) polyoxyalkylene styryl phenyl ether used in the cleaning composition to which the present embodiment is applied includes one having a structure represented by the following general formula (1).

Here, in the formula (1), R ₁ is an alkylene group having a straight chain or branched chain of 4 carbon 2 atoms carbon atoms, n is addition mole number of styryl group (1 to 3), m is oxy The number of moles of alkylene group added (1 to 10).

Next, the polyoxyalkylene alkyl ether (b) used in the cleaning composition to which the present embodiment is applied can be obtained as an adduct of an alkylene oxide of a higher alcohol. Examples of the higher alcohol include alcohols having a linear or branched alkyl group having 4 to 18 carbon atoms. Specific examples include 2-ethylhexanol, octanol, decanol, lauryl alcohol, isodecyl alcohol, tridecyl alcohol, myristyl alcohol, stearyl alcohol, oleyl alcohol, octylphenol, nonylphenol, dodecylphenol, etc. Is preferred.
The alkylene oxide is preferably one having 2 to 4 carbon atoms. Among the alkylene oxides, ethylene oxide having 2 carbon atoms and propylene oxide having 3 carbon atoms are preferable, and ethylene oxide is particularly preferable. Moreover, what has the block structure of ethylene oxide and propylene oxide can also be used. The added mole number of alkylene oxide is usually 1 to 10 moles, preferably 5 to 7 moles, and particularly preferably 6 moles from the viewpoint of water solubility and solubility in liquid crystals.

As a preferred embodiment of the (b) polyoxyalkylene alkyl ether used in the cleaning composition to which the present embodiment is applied, one having a structure represented by the following general formula (2) can be mentioned.
R ₂ —O— (R ₃ O) ₁ H (2)
Here, in the formula (2), R ₂ is a linear or branched alkyl group having 4 to 18 carbon atoms, and R ₃ is a linear or branched alkylene group having 2 to 4 carbon atoms. Where l is the number of added moles (1 to 10) of the oxyalkylene group.
Among (b) polyoxyalkylene alkyl ethers represented by the general formula (2), polyoxyethylene isodecyl ether having an addition amount of ethylene oxide of 6 mol is particularly preferable.

The cleaning composition to which the present embodiment is applied is composed of 20% to 60% by weight, preferably 30% to 50% by weight of the polyoxyalkylene styryl phenyl ether component (a), and the component (b). Containing 40 wt% to 80 wt%, preferably 50 wt% to 70 wt% (provided that the sum of (a) and (b) is 100 wt%). Is. The mixing method of a component (a) and a component (b) is not specifically limited, A normal mixing method can be used.
The cleaning composition to which the present embodiment is applied can be used as it is as a mixture of component (a) and component (b), but if desired, it should be prepared in the form of an aqueous dispersion. Can do. When used in the form of an aqueous dispersion, the composition ratio of each component in the aqueous dispersion is not particularly limited. Usually, the polyoxyalkylene styryl phenyl ether as the component (a) and the polyoxyalkylene alkyl as the component (b) are used. It contains 100 g to 1000 g of water as component (c) with respect to 1 g of the mixture with ether. Here, it is preferable to use ion-exchanged water as the water as the component (c).

  The cleaning composition prepared in the form of such a low-concentration aqueous dispersion can be used as a cleaning agent for a liquid crystal cell that exhibits excellent performance in cleaning and removing liquid crystal adhered to the liquid crystal cell. . A method for cleaning and removing the liquid crystal adhering to the liquid crystal cell using such a liquid crystal cell cleaning agent is not particularly limited, and can be appropriately selected. For example, known means such as immersion cleaning, rocking cleaning, cleaning using rotation such as a spinner, paddle cleaning, air or liquid spray cleaning, and ultrasonic cleaning can be used. Such cleaning means may be carried out singly or in combination. Further, the liquid crystal cells may be washed one by one in a single washing operation, or a plurality of sets may be washed. Further, the number of cleaning tanks used for cleaning may be one or plural. The temperature of the cleaning agent for the liquid crystal cell at the time of cleaning is not particularly limited, but a range of 20 ° C. to 60 ° C. is preferable in terms of safety and operability.

  In addition, other nonionic surfactant can be mix | blended with the cleaning composition to which this Embodiment is applied as needed. Examples of the nonionic surfactant include one or more of a polyalkylene polyamine polyalkylene oxide adduct, a polyhydric alcohol fatty acid ester, a polyhydric alcohol fatty acid ester polyalkylene oxide adduct, and a benzylated phenol polyalkylene oxide adduct. Is mentioned.

Hereinafter, the present embodiment will be described more specifically with reference to examples. However, this embodiment is not limited to the following examples unless it exceeds the gist.
(Examples 1 to 4, Comparative Example 1, Comparative Example 2)
A JIS comb electrode type 2 electrode plate was used as an object to be cleaned, and a liquid crystal (fluorine-based liquid crystal: TM9701LA manufactured by Merck Co., Ltd.) was uniformly applied thereto to obtain an evaluation substrate. Next, cleaning agents ((1) to (4)) having the compositions and concentrations shown in Table 1 were prepared, and an evaluation substrate coated with liquid crystal was immersed in an aqueous solution of these cleaning agents at 40 ° C. for 2 minutes. Then, it was washed with running water for 1 minute and dried in a clean oven (80 ° C.) for 30 minutes.
Subsequently, a sine wave having a frequency of 100 Hz was applied to the dried electrode, and the phase difference (tan θ) due to an alternating alternating electric field was measured as a dielectric loss amount, and the influence of the cleaning agent remaining on the evaluation substrate was evaluated. In the region of a frequency of 100 Hz or less, dielectric loss due to surface polarization of adsorbed water and free water appears, and the ions become movable ions, which are a factor for accelerating migration. The smaller the value of the dielectric loss amount, the smaller the influence of the cleaning agent remaining on the evaluation substrate, and the better the cleaning agent for the liquid crystal cell.
For comparison, the same conditions were applied to ethylenediamine-based cleaning agents (cleaning agent A: LGL manufactured by Yokohama Oil & Fats Co., Ltd.) and catechin-based cleaning agents (cleaning agent B: natural sleeper manufactured by ITO EN Co., Ltd.) under the same conditions. The amount of loss was measured. The results are shown in Table 1.

From the results shown in Table 1, polyoxyethylene styryl phenyl ether (component (a)) and polyoxyalkylene isodecyl ether (component (b)) were mixed at a weight ratio (a) :( b) = 1: 2. The cleaning agents (Example 1 to Example 4) prepared by mixing and preparing an aqueous dispersion having a concentration of 0.5% by weight have a measured value of dielectric loss (tan θ) in a dry state (dry) and a humidified state (wet). It can be seen that each of these has a small, low cost, and excellent performance as a safe liquid crystal cell cleaner.
Among them, polyoxyethylene monostyryl phenyl ether (MSP: ethylene oxide addition amount: 5 mol) and polyoxyethylene isodecyl ether (SD: ethylene oxide addition amount: 6 mol) were mixed at a weight ratio of 1: 2. It can be seen that the cleaning agent (1) (Example 1) has a small measured value of dielectric loss (tan θ) and has a particularly small influence on the electrode formed on the evaluation substrate.
On the other hand, the ethylenediamine-based cleaning agent (cleaning agent A: Comparative Example 1) has a small influence on the electrode of the evaluation substrate, but needs to be used in a high concentration state in order to remove the liquid crystal attached to the electrode. It can be seen that the cost as a cleaning agent is extremely high. Further, it can be seen that the catechin-based cleaning agent (cleaning agent B: Comparative Example 2) has a large measured value of dielectric loss (tan θ), and in particular, the migration is accelerated in a humidified state (wet), and the influence on the electrode is large.

(Example 5, Comparative Example 3, Comparative Example 4)
The liquid crystal adhering to the evaluation substrate was washed and removed under the same conditions as in Example 1 using the cleaning agent (1) used in Example 1, and the fragment ions due to the liquid crystal residue remaining on the electrodes were measured using TOF-SIMS. did. For comparison, the cleaning agent A used in Comparative Example 1 and the cleaning agent B used in Comparative Example 2 were also subjected to the same operation as in Example 1, and then fragment ions due to liquid crystal residues remaining on the electrodes. Was measured using TOF-SIMS. The results are shown in Table 2.

From the results shown in Table 2, polyoxyethylene monostyryl phenyl ether (MSP: ethylene oxide addition amount: 5 mol) and polyoxyethylene isodecyl ether (SD: ethylene oxide addition amount: 6 mol) were used in a weight ratio of 1: 2. The cleaning agent (1) (Example 5) prepared by mixing in (5) has a small amount of fragment ions measured using TOF-SIMS, so that there is little liquid crystal residue remaining on the electrode, and as a cleaning agent for liquid crystal cells. It can be seen that the cleaning ability is excellent.
On the other hand, the cleaning agent A (Comparative Example 3) and the cleaning agent B (Comparative Example 4) have a large amount of liquid crystal residue remaining on the electrode. In particular, the cleaning agent B has about 5 times the liquid crystal residue of the cleaning agent (1). It can be seen that remains.

  As an application example of the present invention, for example, it can be applied as a cleaning agent for dirt such as various oils such as cutting oil, press oil, and drawing oil attached to precision parts, wax, grease and the like.

Claims (13)

(A) 20% to 60% by weight of polyoxyalkylene styryl phenyl ether;
(B) 40% by weight to 80% by weight of polyoxyalkylene alkyl ether (provided that the total of (a) and (b) is 100% by weight).   The cleaning composition according to claim 1, wherein the (a) polyoxyalkylene styryl phenyl ether is a polyalkylene oxide adduct of styrenated phenol.   2. The cleaning composition according to claim 1, wherein the (a) polyoxyalkylene styryl phenyl ether is an addition polymer of a styrenated phenol and an alkylene oxide having 2 to 4 carbon atoms.   The cleaning composition according to claim 3, wherein the styrenated phenol has a purity of monostyrenated phenol of 85% or more.   2. The polyoxyalkylene styryl phenyl ether (a) is an addition polymer of 1 mole of styrenated phenol and 4 moles to 5 moles of alkylene oxide having 2 to 4 carbon atoms. Cleaning composition.   The cleaning composition according to claim 1, wherein the polyoxyalkylene styryl phenyl ether (a) is an addition polymer of 1 mol of monostyrenated phenol and 5 mol of ethylene oxide.   The cleaning composition according to claim 1, wherein the (b) polyoxyalkylene alkyl ether has a linear or branched alkyl group having 4 to 18 carbon atoms.   2. The cleaning composition according to claim 1, wherein the polyoxyalkylene alkyl ether (b) has 1 to 10 moles of addition of an alkylene oxide having 2 to 4 carbon atoms.   The cleaning composition according to claim 1, wherein the (b) polyoxyalkylene alkyl ether has an isodecyl group.   The cleaning composition according to claim 1, wherein the polyoxyalkylene alkyl ether (b) has 6 added moles of alkylene oxide having 2 or 3 carbon atoms.   The (a) polyoxyalkylene styryl phenyl ether is 30 wt% to 50 wt%, and the (b) polyoxyalkylene alkyl ether is 50 wt% to 70 wt%. Cleaning composition. (A) A mixture of 20% to 60% by weight of polyoxyalkylene styryl phenyl ether and (b) 40% to 80% by weight of polyoxyalkylene alkyl ether (provided that the sum of (a) and (b) is 100 Weight percent)
A cleaning agent for a liquid crystal cell, which contains (c) 100 g to 1000 g of water with respect to 1 g of the mixture.   The cleaning agent for liquid crystal cells according to claim 12, wherein the water (c) is ion-exchanged water.