JPS5859228A - Anti-fogging treatment of cellulose triacetate plastic molding - Google Patents

Abstract

PURPOSE:To impart excellent anti-fogging property to cellulose triacetate plastic moldings, by dipping the molding products in a warm aqueous solution containing caustic alkali, lower fatty acid ester of glycerol, phosphate plasticizer, etc. CONSTITUTION:A processing solution is prepared by dissolving 40-80g of sodium hydroxide and/or potassium hydroxide and at least 10ml of lower fatty acid ester of glycerol (e.g. monoacetin or triacetin) and/or phosphate plasticizer (e.g. trimethyl phosphate or tripropyl phosphate) in 1.000g water. The solution is kept at 50-90 deg.C and cellulose triacetate plastic moldings are dipped in it for 30min- 3hr. Thus excellent anti-gogging property is imparted to the molding and the treated molding is suitable for sun glasses, window pane, bathroom mirror, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating slight fogging of cellulose triacetate plastic moldings.

Recently, plastic molded products have been used in many fields such as general sunglasses, ski goggles, industrial dustproof glasses, and motorcycle windshield glasses. Easily 4m with changes! This was extremely inconvenient to use. For this reason, various anti-fog treatments are applied to plastic molded products, including UIP! S, 70
0,487, the method of making the surface of a molded article hydrophilic by saponification treatment to produce an antifogging effect is well known, and is widely used because the effect is semi-permanent with a simple treatment. For example, in the case of cellulose diacetate plastic molded products, 1/
Hydroxide at a concentration of 2N to 1N) IJum or potassium hydroxide aqueous solution for 15 minutes to 60 minutes! By IR immersion, it is possible to easily obtain cellulose diacetate plastic moldings having antifogging properties. However, Cell A-diacetate plastic has poor water resistance and dimensional stability, and has drawbacks such as deformation of the molded product when left in a hot and humid environment for a long time. The emergence of plastic molded products with excellent water resistance and dimensional stability has been eagerly awaited.

The present inventor attempted to saponify nine-cellulose triacetate plastic moldings, which have much better water resistance and dimensional stability than cellulose diacetate plastic moldings, but the conventional saponification treatment carried out on cellulose diacetate plastic moldings It became clear that this method could not provide any antifogging properties. The inventors of the present invention have conducted extensive research into a method for imparting an antifogging effect to cellulose triacetate plastic molded articles, and as a result, have arrived at the present invention.

That is, in the present invention, for 1000 yK of water, -) sodium hydroxide or (and) potassium hydroxide is 40- to saf,
(→A solution obtained by adding and dissolving 1,000 or more lower fatty acid esters of glycerin or (and) phosphoric acid plasticizers (A
) is maintained at 50° C. for 90'CK, and the (A) K cellulose triacetate plastic molded product is immersed in this solution for 50 minutes to 3 hours. Lower fatty acid ester of glycerin used in the present invention Specific examples include monoacetin, diacetin, and triacetin. Specific examples of phosphoric acid plasticizers include trimethyl phosphate, triethyl phosphate, and tripropyl phosphate.

As described above, the present inventors have conducted many studies to impart antifogging properties to cellulose triacetate plastic molded products. Otherwise, it is not possible to obtain a cellulose triacetate plastic molded product with good antifogging properties.

That is, an aqueous solution of sodium hydroxide and potassium hydroxide alone will hardly provide antifogging properties no matter how high the concentration.

Cellulose triacetate, which is the main component of the cellulose triacetate plastic molded product treated in the present invention, is obtained by esterifying one or all of the hydroxyl groups of cellulose with acetic acid, and the cellulose triacetate treated in the present invention has a high degree of acetylation. 41.541i to 44
．． 78- and a degree of 1'.00 or more is suitable, and its properties are completely different from cellulose diacetate, which has a degree of acetylation of ang6 or less. In addition, the blending ratio of the lubricant added to such cellulose triacetate plastic is
3 to 100 parts by weight of SO.

Such softening agents include dimethyl phthalate, diethyl 7
7) Phosphate esters such as -rate, dimethoxyethyl phthalate, dimethoxyhexyl phthalate, phosphate esters such as triphenyl phosphate, tricresyl phosphate,
Glycerin derivatives such as triacetin and tributyrin, glycol fermentation conductors such as methyl phthalylethyl glycolate, ethyl phthalyl ethyl glycolate, butylphthalyl butyl glycolate, p-toluenesulfonamide,
Sulfonic acid cast conductors such as toluenesulfone-N-ethylamide, other adipic acid-conductors, azelaic acid cast conductors, diglycerin, polyglycerin, pytaerythritol, dipentaerythritol, trimethylol ethane,
III alcohol lower fatty acid esters such as trimethylolethane, liethylolethane, ditrimethylolethane, sorbitol, m; Plasticizers commonly used in cellulose triacetate plastics can be used, such as esters, bisphenol epoxy resins, and the like.

In addition, cellulose triacetate plastic has Purpose K.
Various dyes and pigments, fillers, and stable ring-opening agents may be added.

Any known technique may be used to obtain a molded product from W cellulose triacetate plastic, but it is usually produced by the following method: 1) Casting method.

2)! Method I method or Plutz method 5) Dry method In other words, a method of obtaining a molded product using a maturing machine such as an injection molding machine or an extruder. ,bending,
The desired molded product can be obtained by processing such as adhesion.

Potassium hydroxide, sodium hydroxide, lower fatty acid ester of glycerin, and phosphoric acid plasticizer used in the ninth stage of preparing the treatment solution (A) of the present invention may be commercially available products, but due to purity It is preferable to use

In the treatment solution of the present invention, hydroxylated F as component (a)
Lithium and potassium hydroxide may be used alone or in combination, and the amount added is preferably in the range of 40 t to .Qf per 1000 fK of water. If the amount added is less than 401, it is difficult to impart satisfactory antifogging properties to the cellulose triacetate gelastic molded product.If the amount added is more than 401, the surface of the cellulose triacetate plastic molded product will have adverse effects such as whitening and rough skin. This is not desirable considering the intended use.

In addition, lower fatty acid ester of glycerin and phosphoric acid plasticizer are used alone or in combination as component (b), and the amount added is 40 to 801 tons of sodium hydroxide and potassium hydroxide alone or in combination per 1000 tons of water. It dissolves at a ratio of 10 cc to IQQaa relative to the hydrotactic solution. If the amount added is less than 10 ac, it is difficult to impart satisfactory antifogging properties to cellulose triacetate plastic molded articles. In addition, if the amount added is more than 100 co, there will be no negative effects such as whitening and rough skin on the surface of the plastic molded product. Cellulose diacetate plastic is added to the solution (A) obtained by adding 1,000 or more of a lower fatty acid ester of glycerin and a phosphoric acid plasticizer, alone or in combination, to an aqueous solution in which 49f to 80f are dissolved in the solution (A), alone or in combination. When the molded product is immersed, it imparts antifogging properties, but the immersion temperature and time range is from 50°C to 9°C.
0° C. and a time range of 50 minutes to 5 hours are preferred. temperature is 5
The reason for this is that at temperatures below 0°C, cellulose triacetate plastic moldings are provided with satisfactory antifogging properties.

On the other hand, if the temperature is 90 DEG C. or higher, the two-stick molded product of cellulose triacetate tends to be deformed, which is not preferable. If the immersion time is less than sO minutes, the cellulose triacetate gelastic molded product will be released with satisfactory antifogging properties.If the immersion time is more than S hours, the cellulose triacetate plastic molded product will not swell or whiten. occurs,
In addition, deformation may occur (Undesirable) The solution used for antifogging treatment of cellulose triacetate plastic molded products according to the present invention (in addition, solvents, surfactants, buffers, detergents, etc. These substances can be added within a range that does not impede the effects of the present invention.

Cellulose triacetate plastic moldings made according to the method of the present invention can be used regardless of how the ambient temperature and humidity change under normal living conditions (e.g. outdoors in rainy weather or blinding weather, or When indoors, there is no fogging at all, even when running in and out of the bathroom, etc.). Unlike cellulose diacetate plastic molded products, it has poor water resistance and dimensional stability, so it can withstand use outdoors and in hot and humid environments.

This kit is completely KVi frosted salt treated cellulose triacetate plastic molded ski goggles,
It can be used for many purposes such as industrial dustproof glasses, sunglasses, underwater glasses, windshield glasses for motorcycles, various glass substitutes for passenger cars, bathroom mirrors, window glass substitutes, etc.

Hereinafter, preferred embodiments of the present invention will be described. Examples 1 to S and Comparative Examples 1 to 4 5 parts by weight of triphenyl phosphate as a lubricant for 100 parts by weight of cellulose triacetate (acetyl group 42JO, polymerized [1sffo]) cellulose triacetate plastic sheet) (40m/Otori
70 II / II X 1,311 / Ill
) was subjected to anti-fog treatment by the method shown in Table 1 and Table 11C. Anti-fog treated (Nine sea) K temperature 15℃, temperature No@
In the R,H,O room, temperature 40℃, humidity 9s-R,H,
The anti-fogging effect was examined by blowing hot air for sO seconds and checking whether the sheet became foggy or not. Show the results! (Example)
As shown in Table - Summer' (Comparative Example), the sheet surface according to the example of the present invention did not have any fogging spots at all, but
According to Comparative Example 1, anti-fog treatment was not applied, so
#h) was instantaneously generated on the sheet surface. Also, Comparative Example 2.
IS, 4 did not contain lower fatty acid ester of glycerin or phosphoric acid-based binder, and the antifogging performance was low, and bad image changes such as swelling and deformation and whitening of the sheet occurred.

The present invention makes it possible to impart an antifogging effect to cellulose triacetate as described above.

Table-! Table - ■

Claims (1)

[Claims] Water 100 (for IK, sodium hydroxide or (and)
Potassium hydroxide 4 jf~@Of1 lower fatty acid ester of glycurin or (and) phosphoric acid plasticizer 1000
The solution obtained by adding and dissolving the above solution (4 from 50℃?'
A method for antifogging a cellulose triacetate plastic molded product, which comprises maintaining O'CK and immersing this solution (A) K cell 4-striacetate plastic molded product in SO for 5 hours.