JPH02191641A - Surface treating solution of molded fluorine-based resin product - Google Patents

Abstract

PURPOSE:To obtain the subject treating solution capable of exhibiting well- balanced treating effects, operating efficiency, stability, economical efficiency and storability by adding a specific aluminum compound and liquid paraffin to a solution containing a complex of Na with naphthalene. CONSTITUTION:A surface treating solution for molded fluorine-based resin products obtained by dissolving a complex of sodium with naphthalene is ethylene glycol.dimethyl ether and/or butylene glycol.dimethyl ether to provide a solution and blending aluminum distearate and/or aluminum monostearate and liquid paraffin therewith. The amounts of the added components based on 100g sodium dispersion of the naphthalene medium are within the range of 500-1000ml ethylene glycol.dimethyl ether, 0.5-10g aluminum distearate and 5-50g liquid paraffin.

Description

DETAILED DESCRIPTION OF THE INVENTION (l) Industrial Application Field The present invention relates to a surface treatment liquid for improving the adhesion of fluorine yarn FHWft molded articles.

(2). Prior Art The present invention relates to a surface treatment liquid used for imparting adhesive properties, chemical plating properties, etc. to fluorine resin one-finger molded products.

Fluorine resins, such as tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA),
Tetrafluoroethylene/hexafluoropropylene copolymer (FEP), polytetrafluoroethylene (TF
E) etc. are currently widely used in the field of products because they have many outstanding physical and chemical properties. For example, it is used as an exterior material for the fixing roller of Blend Vapor Copier (PPC) because of its excellent heat resistance and non-adhesive properties, and it is also processed into adhesive tape because of its small coefficient of friction. Some sliding parts are non-contaminating (
They are used for wallpaper or as surface materials for self-sale products due to their easy decontamination properties, and some are used for printed wiring boards as electrical insulating materials with low dielectric properties.

As is known from the above usage example, fluororesin is used in combination with ordinary materials, but due to its chemical structure, fluorine fiber FfR resin is non-adhesive, so it does not mix with other materials as it is. Compounding is difficult. For this reason, conventionally, the surface of fluororesin molded products has been treated with an alkali metal solution to make the fluorine on the surface tIII'l in a chemical reaction to make it abrasive, or it has been roughened by plasma irradiation, which is a so-called physical etching treatment. It is possible to apply adhesive by applying the adhesive.

The latter method requires a vacuum device, which is also large-scale, and is inconvenient in cases where the shape is complex or where partial treatment is desired, whereas the former method requires the solution to be applied to the desired location. The most common method is to process and wait for a while.

As an alkali metal solution, a solution in which sodium is dissolved in liquid ammonia has been known for a long time. Although this solution is easy to prepare, it requires low temperature storage, and the solvent ammonia does not easily evaporate and is harmful as it can be agitated.
It is not common because it is difficult to manage the work environment.
Instead, a so-called naphthalene medium sodium dispersion, in which sodium is dispersed in naphthalene, which has low toxicity and a relatively high boiling point, is often used as the main ingredient of the surface treatment liquid.

In addition to alkali metal solutions, iron, pentacarbonyl, etc. are said to be effective as surface treatment agents for fluororesin.
Its efficacy is comparable to that of sodium metal, and penta-iron carbonyl itself is not common, so it cannot be used practically.

(3) 1. Problems to be Solved by the Invention The sodium dispersion in the naphthalene medium is not a special chemical; 2. It is easily available in the market and has a powder, granule, solid, or other appropriate form. . In addition, since the hydrocarbon solvent solution is relatively easy to store and handle, it is easy to use for surface treatment of fluororesin.

However, the metallic sodium it contains is easily affected by water, and not only does its effectiveness decrease when it is oxidized by moisture or oxygen in the air, but it also poses a risk of ignition if it comes into direct contact with moisture.

In addition, the dispersion state is unstable and processing performance is likely to deteriorate.
The influence of moisture and oxygen largely depends on the concentration and dispersion state of the sodium dispersion in the naphthalene medium, so in order to improve handleability and prevent a decrease in efficacy, it is necessary to use M, such as dispersants and stabilizers. You can devise ways to adjust the type and amount of addition. For example, the Japanese Patent Publication No. 43-2 known as prior art
No. 595 (hereinafter referred to as the prior art), by mixing paraffin into an organic solvent solution of chains of alkali metals and naphthalene, etc., problems with handling such as spontaneous ignition, reduction in efficacy due to oxygen and moisture in the atmosphere, and long-term Dispersants and stabilizers work to stabilize the dispersion and dispersion state, but because of their mechanism of action, they have a negative impact on surface treatment effects (e.g. wetting tension), treatment time, and treatment placement. The selection of these materials is important in terms of processing effectiveness, workability, safety, and economic efficiency, as processing workability, stability, cost, stability of solutions over time, storage stability, and uniformity of processing also change. .

That is, in the prior art mentioned above, the processing effect, processing time,
Deterioration of workability in post-processing such as cleaning has been pointed out as a drawback.

(4) Means for Solving Problem 1 The present invention is based on a solution in which a sodium dispersion in a naphthalene medium is dissolved in ethylene glycol dimethyl ether and/or butylene glycol dimethyl ether to form a complex of both. Fluorine f! As a surface treatment agent for oil molded products, it provides a well-balanced formulation with excellent processing effects, workability, stability, economic efficiency, and storage stability. It is characterized by the selection of aluminum and/or aluminum monostearate and liquid paraffin. At this time, it is unclear whether all or part of the sodium dispersion in the naphthalene medium forms a complex, but either is within the scope of the present invention, and it is likely that the sodium dispersion in the naphthalene medium In addition to forming a complex with and naphthalene, it is presumed that metallic sodium exists in some parts in a dispersed state in the solution. As can be seen from this, there is no particular restriction on the expression that a sodium dispersion in a naphthalene medium is dissolved in ethylene glycol dimethyl ether and/or butylene glycol dimethyl ether. This includes cases in which these conditions exist, cases in which these conditions are mixed, cases in which these conditions exist, and cases in which they are in any other state.

Also, like the prior art, paraffin is used in the present invention, but the difference from the prior art is that the present invention also uses aluminum distearate and/or aluminum monostearate, which is not preferred in the prior art. The advantage is that we were able to select liquid paraffin whose m-p temperature is far below 30°C, and the amount of paraffin added is far below the 5-50% that the prior art prefers, for example, about 1.5-4%. However, the present invention can solve the problems solved by the prior art.9 As mentioned above, the present invention can reduce the amount of acid added to paraffin, and even in such cases, the processing effect, which was a drawback of the prior art, is low. It is possible to eliminate various disadvantages such as long processing time, poor performance in post-processing such as cleaning, and large amount of waste, and the advantages are great.

Next, effective components and component ranges of the present invention are described below, but of course, each component and its component range described here are a preferred embodiment of the present invention, and the present invention There are no restrictions on what can be written.

・Sodium dispersion in naphthalene medium 100g ・Ethylene glycol dimethyl ether 500-1000
1 spade Preferably 600 to 700@n・Aluminum distearate 0.5 to 10 g Preferably 1 to 6 g・Liquid paraffin 5 to 50 g Preferably 1 mouth to 25 g An example of the preparation procedure will be described below.

Content 15j! A propeller type stirrer driven by an air motor, a backflow cooler, and a naphthalene medium sodium dispersion hopper (with temperature control device) are installed in a stainless steel container, and nitrogen gas is introduced from a separate nitrogen gas inlet to cool the air inside the device. Replace with nitrogen gas. Separately weighed 1500mj2 of ethylene glycol dimethyl ether and 40g of liquid paraffin were placed in a container and heated to 400ORP under nitrogen gas flow.
Stir at M for 5 minutes to thoroughly mix ethylene glycol dimethyl ether and liquid paraffin. Hit the sodium limbs of the naphthalene medium in a PE bag from the outside with a hammer and crush it until it becomes particles of several square meters or less. Next, put 235 g of the crushed material into a hopper and crush it for 10 to 15 minutes under nitrogen gas flow. Add a few sips at a time to the mixture of ethylene glycol dimethyl ether and liquid paraffin and stir.

The temperature of the liquid will rise, so adjust it to keep it below 50°C. After the addition of the sodium dispersion in the naphthalene medium, an additional 1
．． Continue stirring for 5 hours. Furthermore, another 10 g of aluminum distearate was added over a period of approximately 15 seconds, and the mixture was stirred for 1.5 hours.

This completes the preparation process and stores the solution in a PE bottle. Just to be sure, take 5 cc of the solution and use a wash bottle to pour water into it until the sodium has no effect, and make sure it doesn't catch fire.

(5) 9 Actions As a chemical surface treatment method for fluororesins, there is a known method in 1958 by Mr. R Nelson of the United States, which uses a complex (11 complexes) in which sodium is added to naphthalene in tetrahydrofuran. .

It is known that this complex is soluble and has a high reactivity when reduced, and when dissolved in ethers, it has the advantage of not causing side reactions such as decomposition. The solution itself is about 2
The method of using ethylene glycol dimethyl ether instead of tetrahydrofuran, which lasts for several months and does not require refrigeration, was already known at the time and is safe because it has a higher flash point and spontaneous ignition point than tetrahydrofuran.

For surface treatment of fluororesin molded products, apply this solution to the surface of the fluororesin molded product, wipe off the solution immediately after a few seconds,
This is achieved by washing with acetone, thoroughly rinsing with water, and drying. In other words, the metallic sodium in the complex extracts fluorine atoms from the surface of the fluororesin molded product to produce sodium fluoride and naphthalene, and the fluorine atoms are extracted from the surface of the fluororesin molded product and active carbonaceous substances are formed on the surface. things are left behind.

Although there are no particular restrictions on the sodium dispersion in the naphthalene medium, the ratio is usually such that 1 gram molecule of sodium is added to 1 gram molecule of naphthalene, which results in an extremely large surface area of sodium. It turns out that it is.

A sodium dispersion in a naphthalene medium can be dissolved in certain ethers, dioxane, tetrahydrofuran, glycerol trimethyl needles, orthoformic acid ester, etc., and forms a complex, but its properties differ depending on the type of solvent. At this time, as mentioned above, it is unclear to what extent the sodium dispersion in the naphthalene medium is a complex.
In addition to forming a complex, it is presumed that there is also a portion where metallic sodium exists in a monodispersed state, but this location cannot be determined.

When the inventors investigated the properties of a conventionally known formulation in which a sodium dispersion in a naphthalene medium was dissolved in tetrahydrofuran (hereinafter referred to as THF), the processing strength was 45'4'8 in terms of wetting index.

Although it showed excellent values, it was found that it ignited when water was mixed in, and it also deteriorated significantly over time.

To improve safety, the solvent was replaced with ethylene glycol dimethyl ether and butylene glycol dimethyl ether, which have a higher flash point and spontaneous ignition point than T) [F], and the ignitability and stability were evaluated, but no significant improvement was obtained. There wasn't. However, there was no odor, which is a problem when using THF, and the working environment was improved. Problems such as ignition due to moisture absorption, oxygen in the atmosphere, consumption of sodium due to moisture absorption, agglomeration and separation of sodium due to insufficient dispersion stability, and performance deterioration can be solved by reducing the particle size by improving the dispersibility of sodium, and by reducing the particle size due to oxygen in the atmosphere. , protection from moisture and improved stability of the solution over time.

In hopes of improving the dispersibility of sodium, we tried increasing the amount of naphthalene and using anthracene in combination.

As a result, it was found that the former method does not ignite when 3 equivalents of naphthalene are used per 1 equivalent of sodium, but in addition to being insufficiently stable over time and cannot be reused, the solid content increases, so cleaning after treatment is difficult. It was also found that it is disadvantageous in the process, and that although it can be used, it is subject to certain limitations in its use. In the latter case, it was found that when an appropriate amount of anthracene was added, the ignitability and stability were slightly improved, but this was not sufficient.

On the other hand, it is important to stabilize the dispersion state and prevent sodium agglomeration in order to improve the stability of the solution over time and to improve the long-term storage and reusability of the solution. When we examined the effects of stabilizers, we found that for solid adsorbents, ignition can be effectively suppressed by adding bentonite 1 and activated carbon in amounts of 0.5 to 10% of the dispersed weight. , there was almost no effect on dispersion stability.

Regarding dispersants, we investigated various fatty acid esters, oleic acid and maleic acid, and found that oleic acid
J/j! Since it was known that dispersion stabilizers are highly effective in improving stability and preventing ignition, we conducted further research into dispersion stabilizers, including n-capric acid, abietic acid,
When stearic acid, aluminum stearate, etc. were evaluated, it was found that the addition of aluminum stearate, especially aluminum distearate, has an effect that exceeds that of oleic acid in terms of development prevention IF and dispersion stability. During this time, it was known that if the sodium particle size was large, it would cause sedimentation over time, which would affect the yield, so we adopted high-speed stirring using a five-wheel motor to improve the dispersion state. Immediately after 24 hours of release, there was no sediment, and the time required for adjustment was significantly shortened. Furthermore, in order to improve safety (fire prevention + F, It was also found that the stability over time was significantly improved, and the surface treatment performance was as good as that of only an organic solvent solution of a sodium dispersion in a naphthalene medium. As a result, compared to the case where the amount of naphthalene was increased, there was a dropout (due to naphthalene precipitation).
Processing defects (poorly processed areas) are also eliminated, the reduction in solid content facilitates cleaning after surface treatment, and the increased amount of expensive naphthalene can be compensated for by using inexpensive liquid paraffin, preferably by using a small amount of paraffin. As mentioned above, the surface treatment liquid for fluororesin molded products according to the present invention is expected to reduce costs and also significantly reduce the time required for waste liquid treatment, which is associated with pollution. Preferably, ethylene glycol dimethyl needle is used as the illumination medium, aluminum distearate is preferably used as the dispersant, and liquid paraffin is preferably used as the stabilizer. In this case, in the present invention, for convenience, the expressions dispersant and stabilizer are used. Although I would like to use this expression, it goes without saying that the present invention is not limited by this expression.

Furthermore, there is no problem in adding other materials to the extent that they do not interfere with the effects of the product, and almost the same effects can be obtained by using aluminum thenostearate instead of ethylene glycol dimethyl ether as the solvent. .

A preferable composition ratio of the surface treatment liquid according to the present invention is as defined in claim 3.
As described in 4 and 5. That is, if the amount of ethylene glycol dimethyl ether (butylene glycol dimethyl ether!1) per 100 g of sodium dispersion in the Natsuta/in medium is more than 10@β, the processing performance (leakage tension index) tends to decrease; If it is less than ε, the sodium dispersion in the naphthalene medium will not be completely dissolved and will easily catch fire, and the balance with the dispersant may be lost and the processing solution may become unstable. If the amount is less than 0.5 g per 100 g of sodium dispersion in the naphthalene medium, the viscosity may become low, resulting in poor dispersibility and easy separation.Also, if the amount is more than 10 g, the effect of increasing the amount will be poor.Amount of Liquid Paraffin Naphthalene Medium If it is less than 5g per f00g of sodium dispersion, the dispersion state of sodium will become unstable and it will tend to separate and deteriorate.If it is more than 50g, the viscosity will increase and it will be difficult to perform surface treatment work, removal and cleaning after treatment. Workability also deteriorates.

There is also fear. The Yokomichi ratio of the surface treatment liquid described in -1- below is only a preferable range, and the values described in F below are not considered as adverbs in the present invention, and it can be used even if it deviates from such a value. Of course there is.

Incidentally, if the sodium dispersion in the naphthalene medium is coarsely ground, it may not be completely dissolved in the solvent and a precipitate may be formed, which may easily cause ignition.

The following will explain based on examples.

<Example 1> Add 40 g of liquid paraffin to 1500 sβ of ethylene glycol dimethyl ether, mix with stirring, and add 235 g of crushed sodium dispersion of naphthalene medium to this in a small amount while stirring so as to keep the in degree below 50°C in a nitrogen atmosphere. Pour in and dissolve over a period of approximately 15 minutes. Continue stirring for an additional 1□5 hours. Next, 10 g of aluminum distearate was added over a period of about 10 seconds, and further 1.
Continue stirring for 5 hours. Transfer the treated solution into a PE bottle. I put 5cc of this treatment liquid into a petri dish and poured water into it until the sodium was neutralized in a washing bottle, but it did not catch fire, indicating that it is extremely safe! 〕won.

A cotton swab was impregnated with the treatment solution and applied to one side of a 0.5 ml thick fluorocarbon resin PFA sheet. After a few seconds, the swab was washed with inpropyl alcohol, then water, and air-dried. The wet tension of the treated surface was 45 Da''/cra or more.

This surface was coated with epoxy adhesive and a separately prepared E
PDM! Two sheets were pasted together.

The measurement results of peel strength and shear strength at 150°C are as follows.

(Hereinafter referred to as "self-leaf") Table 1 Adhesive strength in 150℃ atmosphere Adhesive peel strength (Kg) Shear strength (kg), 0.344
6 (manufactured by O RECO Co., Ltd.) MOS-101, (manufactured by Konishi-Zundo Co., Ltd.) 7 Lardite (manufactured by CJDA-GEJGY Co., Ltd.) 0, 03 0, 15 0, 12 7.1 pieces 1, 4 2, 8 As a result, adhesion Although there are differences depending on the type of agent, all have high shear strength.

It is sufficient to prevent walking and wrinkles during use in applications such as roll covers.

"Peel Strength Measuring Method" Two sample pieces with a width of 15-1 are cut from the above-mentioned PFA sheet, and adhesive is applied to each treated surface over a length of 15 m5 from the tip. Align the tips of the two sample pieces, overlap the adhesive-applied parts, and leave them to adhere.

After the adhesive has sufficiently hardened, each of the non-contact parts at the other end is gripped with two chucks of the measuring device, and then pulled at a speed of 20 cm per minute to measure the so-called T-peel strength.

"Method for Measuring Shear Strength" Two specimens with a width of 15 mm are cut from the above-mentioned PFA sheet, and adhesive is applied to each treated surface over a length of 15 gcm from the tip. The adhesive coated parts are placed on top of each other so that the cloth parts do not overlap and are located at opposite ends, and are left to adhere.

Each of the non-adhesive areas located at the other end is grasped by each of the two chucks of the measuring device, and then pulled at a speed of 20 cm per minute to measure the so-called shear strength.

<Example 2> Molded with fluororesin FEP, inner diameter 45-m, thickness 0,
One end of a heat-shrinkable tube of 5 mm, length 40c++, and diametrical shrinkage rate of 20% was closed with a polyethylene cap, and the same treatment solution as used in Example 1 was injected from the other opening, and the tube was heated for several seconds. I then transferred it to another container. After that,
First, the inner surface was cleaned with isopropyl alcohol, and then with water to remove water-soluble components such as salts and bases generated during surface treatment, and air-dried. The inner surface of the heat shrink tube has a brownish color and its wet tension is 45''/c.
m was shown.

An epoxy adhesive was applied to the outer surface of the aluminum vibe, and the vibrator was inserted into the fluororesin heat-shrinkable tube, and then the heat-shrinkable tube was heat-shrinked using a hot air gun.

After the adhesive had hardened, I tried to remove the aluminum pipe, but it was strongly adhered to the fluororesin tube and could not be removed.

On the other hand, when similar measures were taken using a similar FEP heat-shrinkable tube without internal surface treatment, the vibrator could be removed from the heat-shrinkable tube by twisting the vibrator.

<Example 3> Using the treatment liquid used once in Example 2, fluorine yarn f!
The inner surface of a heat-shrinkable tube made of lubricant PFA was treated in the same manner as in Example 2. As a result, the inner surface of the tube quickly turned brown and exhibited a wetting tension of 45''/CI.

A silicone-based heat-resistant adhesive was applied to the surface of a separately prepared silicone-based rubber roller, and the roller was inserted into the tube, and then the heat-shrinkable tube was heated and shrunk in a hot air oven.

After the adhesive had hardened, it was used as a roller for the toner fixing part of a blended vapor copier (PPC), and it withstood 500,000 passes without peeling from the silicone rubber.

(6) Effects of the 3 Inventions Because fluororesins have a number of unique properties, their field of application has been rapidly expanding in recent years. Since it is used in combination with Toshin's materials, it is first required to provide adhesive properties in order to meet market needs.

Do you use physical methods or chemical methods to impart adhesion? Among the known methods, a simple method uses a solution whose main component is a sodium dispersion in a naphthalene medium dissolved in a V& solution.

Although this product has the advantage of being usable at room temperature, it has problems with usability, safety, stability, and long-term storage in the atmosphere, causing ignition and deterioration over time.

There is prior art to improve these problems, and we introduce a popular formulation that protects from oxygen and moisture and prevents ignition by adding paraffin to an organic solvent solution of a sodium dispersion in a naphthalene medium. As a result, the safety and stability of use in the atmosphere and long-term storage properties have been improved, but on the other hand, there are drawbacks such as a decrease in treatment effectiveness and high viscosity that makes surface treatment and removal after treatment difficult. was there.

The present invention effectively solves the problems of safety, stability, and preservability by using aluminum distearate and/or aluminum monostearate as a dispersant, and by adding liquid paraffin to paraffin with a low melting point. We have discovered that even if the amount added is small, the effect can still be expected.As a result, compared to the formulation of the prior art, the treatment effect is high and the treatment time is shortened, and furthermore, the treatment time is reduced. In addition to the advantages such as easy removal and cleaning of the treatment liquid, for example, it is possible to use a small amount of stabilizers, etc., which is advantageous in terms of cost. Since the amount is small, it can also be expected that problems related to pollution will be reduced.

In addition, as known from Example (3), the treatment liquid has good storage properties, so it can be used repeatedly after long-term storage, and the treatment effect is also good. The object of the present invention is to provide a surface treatment liquid for fluorine yarn molded articles that is useful in practical use.

Procedural amendment written (voluntary) February 9, 1992 2. Name of the invention: Surface treatment liquid for fluororesin molded products 3. Relationship with the person making the amendment Patent applicant 4. Order for amendment Date (voluntary) 5. Detailed explanation of the invention column 64 in the specification to be amended Contents of the amendment (1) rEPDM on page 19, line 11 in the specification
Correct J to rEPDM (ethylene propylene rubber).

(2), width 151 from the bottom row rPFA sheet on page 20
111 2 sample pieces is revised to ``1 sample piece each with a width of 15+wm from an rPFA sheet and an EPDM sheet''.

(3), 2nd x B, lines 1-2 and page 21, 11-1
In the second line, "on each treated side" is corrected to "on the treated side of the rPFA sheet and on the EPDM sheet."

(4)2. ``Adhesive J'' on page 21, line 3 and page 21, line 3 is corrected to read ``each adhesive.''

(5), width 1 from the rPFA sheet on page 21, line io
Two 5ag sample pieces were placed on an rPFA sheet and EP
DM: Give each person one sample piece with a width of 15 mm from a DM sheet.''

that's all

Claims (1)

[Scope of Claims] (1) The main component is a solution of a complex of sodium and naphthalene in ethylene glycol dimethyl ether and/or butylene glycol dimethyl ether, and the solution contains aluminum distearate and/or aluminum monostearate and a fluid. A surface treatment liquid for fluororesin molded products that contains paraffin. (2) The main component is an ethylene glycol dimethyl ether solution of a complex of sodium and naphthalene, which is obtained by dissolving a sodium dispersion in a naphthalene medium in ethylene glycol dimethyl ether, and the solution contains aluminum distearate and liquid paraffin. A surface treatment liquid for fluororesin molded products. (3), 500 m of ethylene glycol dimethyl ether per 100 g of sodium dispersion in naphthalene medium
3. The surface treatment liquid for fluororesin molded articles according to claim 2, which is blended in an amount ranging from 1 to 1000 ml. (4) The surface treatment liquid for a fluororesin molded article according to claim 2, wherein aluminum distearate is blended in an amount of 0.5 g to 10 g with respect to 100 g of the sodium dispersion in the naphthalene medium. (5) The surface treatment liquid for a fluororesin molded article according to claim 2, wherein liquid paraffin is blended in an amount of 5 to 50 g per 100 g of the sodium dispersion in the naphthalene medium.