JPH041774B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a surface modification method characterized by forming a graft polymer layer on a base material made of a polymeric substance. Base materials made of polymeric substances are widely used as extremely important base materials. However, at present, there are many defects caused by the surfaces of these base materials. For example, generation of static electricity, adhesion,
The drawbacks are poor printability, moisture absorption, sweat absorption, and water repellency. In order to solve these drawbacks, active research on surface modification is being conducted in various fields. One of the methods for modifying a base material made of a polymeric substance is to form a graft polymerization layer. Conventionally, radiation graft polymerization methods, ultraviolet graft polymerization methods, and the like have been studied as methods of this type. The radiation graft polymerization method generates radicals in a polymer base material by irradiating the base material with radiation.
This is a surface modification method in which various monomers are graft-polymerized using the radical as a starting point. The graft polymerized layer produced by the radiation method has excellent durability, but because the energy of the radiation is extremely high, the radiation penetrates not only the surface of the polymer base material but also the inside, impairing the functionality of the base material. . Furthermore, it also has the drawbacks of being more expensive and dangerous than generating low-temperature plasma. The effect obtained by ultraviolet graft polymerization is similar to that of low-temperature plasma graft polymerization, but it requires 10 to 100 times more energy than low-temperature plasma to achieve the same effect, and this method does not absorb enough ultraviolet rays. It has the disadvantage that it is limited only to substances that A low-temperature plasma discharge graft polymerization method is a method for modifying the surface of a polymer base material. This method is
This is a method in which the surface of a polymer substrate is activated by low-temperature plasma discharge, and a polymerizable monomer is graft-polymerized from the active site to form an extremely thin polymer layer on the surface of the polymer substrate. Conventionally known grafting methods of this type include (1) a method in which the surface of a polymeric base material is activated by plasma discharge and then immediately brought into contact with a polymerizable monomer for graft polymerization. (2) A method in which polymer powder is subjected to plasma discharge treatment under a gas pressure of 0.1 mmHg, exposed to oxygen gas, and then graft polymerized in an acrylonitrile solution. (3) Gas pressure
A method in which after high-voltage discharge treatment of 0.2 mmHg or more and 50 mmHg or less, the method is exposed to oxygen gas, and then graft polymerized in a monomer solution capable of radical polymerization. (4) The polymer base material is heated at a gas pressure of 0.01 mmHg or more and 0.1 mmHg or less,
There is a method in which the material is subjected to plasma discharge treatment at an output of 0.01 watts/cm ² or more and 5 watts/cm ² or less, and then exposed to oxygen and then graft-polymerized with a polymerizable monomer. In method (1), the plasma discharge treatment of the polymer base material and the subsequent graft polymerization must be performed in a system that completely removes oxygen, which serves as a radical scavenger, and it is difficult and difficult to develop such equipment. Method (2), which is extremely expensive and impractical, is described in Polymer, Vol. 2, p. 277, 1961, but there is no detailed description of the conditions for plasma discharge treatment of polymer powder. Methods (3) and (4) are
33132, and described in JP-A-59-80443. These methods were considered to be the most practical among methods (1) to (4) above. As a result of detailed experimental studies, the inventors of the present invention found that the amount of grafting in method (3) is often relatively low, and furthermore, it is difficult to control the amount of grafting. In addition, in method (4), the degree of pressure reduction is large during the plasma discharge treatment of polymer base materials, and a large amount of energy and strict equipment are required to maintain this degree of vacuum when processing a large amount of polymer base materials. There are drawbacks. More detailed follow-up tests revealed that the amount of active sites capable of radical polymerization depends on the electrical energy of the process, as shown in FIG. HDPE in Figure 1 is high-density polyethylene with a film thickness of 60 μm. These film pieces were processed using an ungrounded plasma processing device at a frequency of 5 KHz and an Ar gas pressure of 0.04 mmHg. In order to put the low-temperature plasma discharge graft polymerization method to practical use, the present inventors conducted extensive research on plasma treatment conditions that would stabilize the amount of grafting, and surprisingly found that there was almost no grafting in the above-mentioned JP-A-59-80443. The electrical energy used is 1.2 watts.
We have found plasma treatment conditions that allow a stable amount of graft polymer to be obtained at sec/cm ² or higher. That is, stable graft polymerization is possible when plasma treatment is performed with electrical energy of 5 watts/cm ² or more and 50 watts/cm ² or less. When a higher amount of graft polymer is required, it is preferably 50 watts/cm ² or more. The present inventors have discovered plasma treatment conditions that can stably obtain the amount of graft polymer, and have completed the present invention by making it possible to put into practical use a method for surface modification of polymeric substrates by low-temperature plasma discharge graft polymerization. The most characteristic feature of the present invention is the above-mentioned JP-A-59-
Rather than trying to control the amount of grafting by delicately adjusting the plasma treatment time as described in detail in 80443, we performed a low-temperature plasma treatment that generates a stable amount of active sites capable of radical polymerization. The apparent amount of the graft polymer is controlled by the transition metal salt used in combination with the polymer and the graft polymerization reaction conditions. The present invention will be explained in detail below. The polymer base materials used in the present invention include natural polymers such as cotton, linen, silk, and wood, or polyester, polyether, polyamide, polyacrylonitrile, polyethylene, polypropylene, polystyrene, polycarbonate, vinyl chloride, vinylidene chloride, and acetic acid. Cellulose, cellophane, ABS resin,
Examples include synthetic polymers such as acrylic resin, methacrylic resin, phthanol resin, urea resin, melamine resin, and epoxy resin. Furthermore, the composition of these polymeric base materials does not have to be individual, and may be a mixture of two or more types or a block copolymer of two or more types.
Although the shape may be any shape such as fibrous, plate, sheet, cylindrical, or block, the present invention is particularly suitable for films and fiber molded products. In particular, the fiber molded product may be a filament yarn, a spun yarn, a knitted fabric, or a woven fabric, and there is no problem even if these molded products have been subjected to treatments such as dyeing or resin processing. By skillfully combining dyeing processing, resin processing, and low-temperature plasma discharge graft polymerization, we can produce substrates with various functions, substrates with different functions on the front and back sides, substrates with ultra-durable resin layers, and highly durable materials. coloring base material,
It becomes possible to apply it to many fields such as base materials with interference functions. By subjecting at least one side to low-temperature plasma treatment, it is possible to generate active sites capable of radical polymerization on one side of the base material. Furthermore, by subjecting both sides to low-temperature plasma treatment, it is possible to provide active sites on both sides of the base material. These processing surfaces should be appropriately selected depending on the purpose and are not particularly limited. In the present invention, polyethylene terephthalate refers to at least about 75% of repeating structural units.
but,

[Formula] (where -G- is a divalent organic group containing 2 to 18 carbon atoms and bonded to the adjacent oxygen atom through a saturated carbon atom) means a glycol dicarboxylate repeating structural unit. It is something. The terephthalate group may be the only dicarboxylate component of the repeating structural unit, or up to about 25% of the repeating structural unit may be adipate, sebacate, isophthalate, bibenzoate, hexahydroterephthalate, diphenoxyethane-4, Other dicarboxylates such as 4'-dicarboxylate and 5-sulfoisophthalate groups may also be included. Glycols include ethylene glycol,
Polymethylene glycols such as tetramethylene glycol and hexamethylene glycol, branched chain glycols such as 2,2-dimethyl-1,3-propanediol, diethylene glycol, or mixtures thereof can also be used. If desired, up to about 15% higher glycols such as high molecular weight polyethylene glycols can also be used. Various other substances such as matting agents, gloss improvers, anti-tarnish agents, inorganic particulates, etc. may also be added to the polymerization mixture if desired. The low-temperature plasma discharge referred to in the present invention is a gas discharge different from arc discharge or corona discharge, and the ion species constituting the plasma include Ar, He, H ₂ ,
Using N ₂ , NO ₂ , O ₂ , Air, fluorocarbon, halogenated carbon, etc., or a gas mixture of these,
Plasma is generated using direct current, alternating current, high frequency power, etc. In this case, it is preferable to generate plasma between electrodes with an inter-electrode spacing of 1 cm or more and 10 cm or less using an AC high-frequency power source in a gas atmosphere under vacuum. However, if the degree of vacuum is high, the distance between the electrodes should be If the degree of vacuum is low, it is better to narrow the distance between the electrodes. Both electrodes may be a pair of plate-shaped or rod-shaped electrodes, or a combination of a rod-shaped electrode and a drum-shaped or plate-shaped electrode, respectively. Furthermore, the electrode surface may be coated with glass, ceramics, or the like. Further, the electrode may be cooled or heated as necessary. Low-temperature plasma processing equipment may use either an electrode with one electrode grounded to the can body or an ungrounded electrode with both electrodes insulated from the can body, but if an ungrounded electrode is used, It has the advantage of being able to perform the same processing with about half the power of the grounded type. In the present invention, gases that do not contain oxygen and can form radically polymerizable active sites include Ar, He,
It is a gas such as H ₂ , N ₂ , NO ₂ , NO, CO ₂ , CO, halogen, halogenated carbon, carbon fluoride, or a mixture thereof. Next, typical gases containing oxygen gas include oxygen and air.
The oxygen-containing gas is not particularly limited, and a mixture of the above gases may be used. The low-temperature plasma processing conditions related to the present invention can be determined by the gas pressure and processing electrical energy during discharge. The gas pressure in low temperature plasma treatment is 0.01
It is necessary that the temperature is not less than mmHg and not more than 20mmHg.
In other words, practical use at 0.01 mmHg or less is not preferable because it requires a precise device. At 20 mmHg or more, the discharge becomes unstable and localized discharge occurs, which tends to damage the base material and makes it difficult to generate active points. The gas pressure of the present invention is preferably 0.05mm
The range is Hg or more and 10mmHg or less. More preferably, it is 0.1 mmHg or more and 0.2 mmHg or less. It has been found that within this range, the largest number of radically polymerizable active sites is generated within the range that the present inventors have diligently studied without damaging the base material. That is,
When a high amount of graft polymer is required, plasma treatment at 0.1 mmHg or more and 0.2 mmHg or less is an effective method. Usually, a range of 0.05 mmHg or more and 10 mmHg or less is sufficient. If the base material is a sheet-like material, it can be fixed or moved using a drum-type or plate-shaped electrode while in contact with the drum-type or plate-shaped electrode, so that only one side has uniform radically polymerizable active points. It is possible to obtain sheets. By treating one side of a sheet-like material having active sites on one side in the same manner, a sheet-like material having active sites on both sides can be obtained. In addition, by fixing or moving between the electrodes without contacting the electrodes, uniform radically polymerizable active points can be generated on both surfaces. The processing electric energy in low-temperature plasma processing is 1 watts/cm ² or more and 2000 watts/cm ²
It is necessary that the following is true. The processing electric energy can be expressed as E=W×T/S (Watts/sec/cm ² )W: discharge output (watts), T: processing time (seconds), S: electrode area (cm ² ). . When the processing electrical energy is less than 1 watt/sec/ ^cm2 , the
It is described in Example 80443 that a relatively high amount of graft polymer can be obtained and that the amount of graft polymer can be freely controlled within this range by changing the plasma treatment time. Certainly 1 watt.
Such a tendency was confirmed below sec/cm ² . However, as a method for freely controlling the amount of graft polymer, the adjustment range of plasma treatment time is too narrow, and detailed control is actually difficult. Moreover, if the processing electric energy is 2000 watts/cm ² or more, there is a risk of damage to the can body and the base material, making it unsuitable for practical use. In the present invention, the particularly preferred electric energy for the treatment is 5 watts/cm ² or more and 1000 watts/cm ² or less. In particular, the base material used for normal graft polymerization must be treated with plasma in a stable range of 5 watts/cm ² or more and 50 watts/cm ² or less of active sites capable of radical polymerization. This is preferable from the viewpoint of practical use and production control. However, the apparent amount of graft polymer can be controlled by the transition metal salt used in combination with the monomer and the graft polymerization reaction conditions. In addition, if a high apparent amount of graft polymer is required, 50 watts/ ^cm2 or more
It is possible to appropriately select from processing electrical energies of watts/sec/cm ² or less. Low-temperature plasma is generated at a frequency of 5 Hz to 5 Hz between the counter discharge electrodes under the gas pressure and processing electrical energy.
High frequencies such as 100MHz can be used.
Furthermore, as the discharge frequency band, in addition to the above-mentioned high frequency, low frequency, microwave, direct current, etc. can also be used. The low-temperature plasma generator may be either a capacitively coupled type or an inductively coupled type such as the internal electrode type or external electrode type coil type described above. The base material whose surface has been plasma-treated is then exposed to oxygen gas or a mixed gas containing oxygen gas, or taken out into the atmosphere, and the radically polymerizable active points and oxygen generated on the base material surface by the plasma treatment are removed. react. It is not necessary to perform this operation if plasma treatment is performed in oxygen gas or a mixed gas containing oxygen gas. The amount of radically polymerizable active sites generated on the substrate treated in this way is 10 ^-11 mol/cm ² or more 10 ^-8
mol/cm ² or less. When the amount of active sites produced is 10 ^-11 mol/cm ² or less, the apparent amount of graft polymer is small. Further, according to detailed experimental studies conducted by the present inventors, a large amount of energy is required to increase the amount of active sites generated to 10 ^-8 mol/cm ² or more, and the cost becomes too high for practical use. In particular, the preferred amount of active sites for graft polymerization is 10 ^-11 mol/cm ² or more and 10 ^-8 mol/cm ²
It is as follows. The substrate treated in this way was then 0.1
% or more and 90% or more of one or more radically polymerizable monomer dispersion and 0.0001% or more and 0.1% or less of a transition metal salt dispersion, or a mixed dispersion of the monomer and the transition metal salt. Let them touch it. When the base material is brought into contact with the monomer dispersion and the transition metal salt, the combination and order thereof are not particularly determined. The method of bringing the substrate into contact with each dispersion is not particularly defined, such as dipping or coating. In short, it is sufficient to touch the surface of the base material that has active sites capable of radical polymerization. When the base material having an active site capable of radical polymerization is brought into contact with the monomer or the transition metal salt, the surface of the base material is vacuum degassed at 0.1 mmHg or more and 100 mmHg or less or blown with high-pressure inert gas. By washing oxygen gas, impurities, etc. contained in the base material, the graft polymerization reaction proceeds more easily. There is also nothing wrong with carrying out vacuum deaeration or the like after contacting with the monomer, etc. In addition, the graft polymerization reaction can proceed more easily by introducing an inert gas into each dispersion to deoxidize it before or after bringing the base material into contact with the monomer and transition metal salt, or during the reaction. . The concentration of the monomer dispersion is 0.1% or more and 90% or less. Preferably it is 0.1% or more and 50% or less. Within this range, it is easy to control the homopolymerization reaction and increase or control the apparent amount of graft polymer by using the transition metal salt. The concentration of the transition metal salt dispersion is 0.0001% or more and 1%
It is as follows. If it is 0.0001% or less, the effect of suppressing the homopolymerization reaction is extremely low and is not of practical use. 1 more
% or more, the coloring of the base material becomes significant and is not practical. Further, by changing the transition metal salt concentration by changing the monomer concentration, reaction temperature, and reaction time, it is possible to increase or control the apparent amount of graft polymer. The reaction temperature is preferably room temperature or 20°C or more and 80°C or less. The optimum temperature should be appropriately selected depending on the concentration of the reactive monomer, the concentration of the transition metal salt, and the reaction time, and cannot be particularly limited.
The reaction time is in the range of 10 seconds or more and 10 hours or less. The reaction time should be selected depending on the reaction method, reaction temperature, monomer concentration, transition metal salt concentration, etc., and is not particularly limited. The method for the graft polymerization reaction includes a method of exposing the base material to a mixed solution of a monomer and a transition metal salt and heating it at the same time, a method of exposing the base material to the mixed solution, and then appropriately squeezing and heating it. This may be carried out either by bringing the base material into contact with the mixed solution immediately after the heat treatment in the reaction apparatus and dissolving the base material in the same manner, or by heating the base material separately. Furthermore, as described above, there is no problem even if the monomer and the transition metal salt are brought into contact with the base material separately to carry out the graft polymerization reaction. It is preferable to exclude oxygen from inside the graft polymerization reactor. For example, the atmosphere inside the reactor and the dissolved oxygen in the monomer transition metal salt mixed solution, monomer solution, and transition metal salt solution should be excluded from nitrogen gas or other nitrogen gas. Either the solvent is replaced with an active gas, or in the case of the solution, the solvent is degassed by boiling and then replaced with an inert gas, or the base material is brought into contact with the monomer and transition metal salt solution, and then the solution is heated in high-pressure steam. It is preferable to remove as much oxygen as possible by introducing the base material into the substrate. Even if the monomer dispersion consists of an aqueous medium containing a water-insoluble monomer and an emulsifier, inorganic fine particles that do not inhibit radical polymerization, such as SiO ₂ ,
There is no problem even if it contains Al ₂ O ₃ etc. The radically polymerizable monomer used in the present invention should be selected depending on the appropriate use and is not particularly limited. The radically polymerizable monomer is a compound having a carbon-carbon double bond, and is a monomer that polymerizes using a radical as a growing terminal. For example, acrylamide, N-n
- acrylamide compounds such as butoxymethylacrylamide, N-methylolacrylamide,
Acrylic acid, methyl acrylate, ethyl acrylate, N-butyl acrylate, glycidyl acrylate, 2-dimethylaminoethyl acrylate, 2-3-diglomopropyl acrylate,
Acrylic compounds such as diethylene glycol diacrylate, 2-hydroxyethyl acrylate, methoxypolyethylene glycol acrylate, methacrylic acid, methyl methacrylate, butyl methacrylate, isobutyl methacrylate,
Methacrylic compounds such as tertiary butyl methacrylate, glycidyl methacrylate, ethylene glycol dimethacrylate, 2-dimethylaminoethyl methacrylate, tetrahydrofurfuryl methacrylate, trimethylolpropane trimethacrylate, sodium methacrylpropylsulfonate, divinylbenzene, 2-vinylpyridine, N - Vinyl compounds such as vinyl-2-pyrrolidone and vinyl acetic acid; styrene compounds such as styrene and sodium styrene sulfonate; and the like. The transition metal salts used in the present invention include FuCl ₂ ,
( _NH4 ) _2Fe ( _SO4 ) ₂ , CuCl, Cu( _NO3 ) ₂ , _CuSO4 ,
_CuCl2 , Ni( _NO3 ) ₂ , Co( _NO3 ) ₂ , Cr( _NO3 ) ₂ , Pb
(NO ₃ ) ₂ , LiCl, etc., and the base material, monomer,
Depending on the reaction conditions, etc., it is possible to select a transition metal salt suitable for the purpose. The graft polymerization reaction product of the monomer formed on the surface of the base material includes a graft polymer, a homopolymer with good durability, a homopolymer with poor durability, unreacted monomers, etc. . By washing the graft polymerization reaction product in a good solvent of the monomer and the polymer at a temperature of 35°C to 65°C lower than the boiling point of the good solvent, or by ultrasonic cleaning. ,
An apparent graft polymer layer is obtained by removing unreacted monomers and homopolymers with poor durability. That is, the apparent graft polymer layer is composed of an apparent graft polymer containing a graft polymer and a homopolymer having good durability. Furthermore, the homopolymer with good durability is also removed by washing the apparent graft polymer layer with a good solvent for the polymer at a temperature of 0°C to 25°C closer to the boiling point of the solvent or by ultrasonic cleaning. The resulting layer is referred to as a graft polymerization layer. The graft polymer layer is made of a graft polymer. After the graft polymerization reaction, a step of removing the homopolymer with poor durability and unreacted monomers from the graft polymerization reaction product of the monomer formed on the surface of the base material by a chemical or physical method. This makes it possible to obtain a graft polymerized layer that appears to have good durability. Chemical and physical methods include water washing, solvent extraction, and ultrasonic cleaning. By this step and the polymerization reaction conditions, it is possible to control the homopolymer content of the monomers, which exhibits good durability, in the apparent graft polymerized layer. By containing 90% or less of a homopolymer with good durability in the apparent graft polymerization layer, it is possible to form a polymerization layer suitable for various purposes. Advantages of the present invention are (1) According to the method of the present invention, it is possible to suppress or control the formation of homopolymers compared to conventional discharge graft polymerization methods. (2) The active sites generated by the method of the present invention become stable for a long time when brought into contact with oxygen, and can be used when necessary. This is a great advantage in terms of production management. (3) The apparent graft polymer layer formed according to the present invention has excellent durability because it is chemically bonded to the base material. (Four)
By arbitrarily changing the homopolymer content in the apparent graft polymerization layer formed according to the present invention, it becomes possible to meet various uses. The present invention will be explained below with reference to Examples. Example 1 A high-density polyethylene film (thickness: 60 μm) was subjected to Soxhlet extraction with methanol and then dried to prepare a sample. These film pieces were treated on both sides with a non-grounded plasma processing device at a frequency of 5KHz and an argon gas pressure of 0.04mmHg at various outputs and processing times, and then taken out into the air and heated for 10 minutes.
The tube was immersed in a mixed aqueous solution of % acrylamide and 0.005% (NH ₄ ) ₂ Fe (SO ₄ ) ₂ , and the inside of the system was replaced with N ₂ and then sealed.
Graft polymerization was carried out at 50℃ for 2 hours in a sealed tube, and after the polymerization was completed, unreacted monomers and homopolymer were heated to 80℃.
It was removed with hot water and dried under reduced pressure. After the plasma treatment, the amount of radically polymerizable active sites generated by exposure to air was determined as follows. 2,2-diphenyl, a radical scavenger
A film with active sites was immersed in a benzene solution of 1-picrylhydrazyl and heated at 60°C, and the amount of 2,2-diphenyl-1-picrylhydrazyl consumed was determined by a colorimetric method, which was then subjected to radical polymerization. The amount of active points was determined as possible. In addition, the quantification of grafted acrylamide is
It went like this: First, a grafted polyethylene film was immersed in 2.5N hydrochloric acid and heated at 110°C, and after hydrolyzing the grafted polyacrylamide, ninhydrin was added to develop a color, and the _NH3 groups in the decomposition solution were measured using a colorimetric method using a calibration curve. Quantitated by comparing with Comparative Example 1 High-density polyethylene film treated according to Example 1 at 10% concentration in the absence of (NH ₄ ) ₂ Fe(SO ₄ ) ₂
It was immersed in an acrylamide aqueous solution and subjected to the same post-treatment as in Example 1.

[Table] As is clear from Example 1, the amount of active points was reduced to 5 watts due to the plasma treatment electrical energy.
It was stable at ^more than 50 watts/cm2/ ^cm2 . When the electrical energy was further increased, the amount of active sites increased. Furthermore, if the amount of active sites was stable, the amount of graft polymer was also stable at a relatively high amount. Furthermore, as the amount of active sites increased, the amount of graft polymer increased. Due to the presence of the transition metal salt, the solution viscosity within the graft polymerization reaction system did not change, and the homopolymerization reaction was suppressed. Moreover, the amount of graft polymer also increased somewhat under these conditions. Example 2 Polyester cloth (JIS attached cloth taffeta) at 110KHz
Using a high frequency power source with an output of 0.64 W/cm ² , only one side was treated for 40 seconds under the Ar gas pressure shown in the table below. This fabric was taken out into the air and immersed in a mixed aqueous solution of monomers and transition metal salts shown in the table below, and after the system was vacuum degassed, under _N2 , the reaction temperature shown in the table below was maintained for 30 minutes.
After reacting for a minute, unreacted monomers and homopolymers were extracted and removed with 80°C hot water.

[Table] From Example 2, the amount of graft polymer was clearly increased by increasing the monomer concentration and polymerization reaction temperature. Also, transition metal salts (NH ₄ ) ₂ Fe
When the concentration of (SO ₄ ) ₂ was 1% or more, the base material was clearly colored brown and was not of practical use. Also
When it was 0.0001% or less, there was almost no effect of suppressing the homopolymerization reaction, and the viscosity of the reaction system increased extremely, making it difficult to remove the homopolymer. Furthermore, after low-temperature plasma treatment under various Ar gas pressures, a graft polymerization reaction was attempted.
The amount of graft polymer was highest when the Ar gas pressure was 0.1 mmHg or more and 0.2 mmHg or less. Example 3 100% polyester dioset (Dianix
Black BG-FS10% (owf) dyed fabric)
Using 13.56MHz high frequency power supply, Ar gas pressure 0.2
Under mmHg and with an output of 1.24 watts/cm ² , only one side of the non-grounded electrode insulated from the can was subjected to low-temperature plasma treatment for 40 seconds and exposed to oxygen gas. Before bringing the treated fabric into contact with the reaction solution, the vacuum level is 5 mm.
20% sodium sulfopropyl methacrylate and 0.001% (NH ₄ ) ₂ Fe were vacuum degassed under Hg for 10 seconds and deoxygenated by introducing sufficient nitrogen gas in advance.
After immersion in a mixed aqueous solution of ( _SO4 ) ₂ , it was heated at 60℃ under _N2 for 20 minutes.
Allowed to react for minutes. The treated fabric thus obtained,
Unreacted monomers and homopolymers with poor durability were removed by thorough washing with hot running water at 40°C to obtain a fabric having an apparent graft polymer layer. Further, the fabric was thoroughly washed with hot running water at 80°C to remove the homopolymer having good durability, thereby obtaining a fabric having a graft polymer layer.
The apparent graft polymerization layer and graft polymerization layer were determined by weight measurement.

[Table] No increase in the viscosity of the graft polymerization reaction system was observed, and both the obtained fabric with an apparent graft polymerization layer and the fabric with a graft polymerization layer were washed for 50 minutes.
It had a single-sided hydrophilic function that was sufficient to withstand multiple durability tests. Example 4 110K 100% nylon taffeta (JIS attached cloth)
Using Hz high frequency power supply, under air pressure 0.15mmHg,
After 10 seconds of low-temperature plasma treatment on both sides at a power of 0.64 watts/cm ² , the cells were immediately placed in an aqueous dispersion containing 20% hexafluorobutyl methacrylate, 1% sodium polystyrene sulfonate, and 0.05% Mohr's salt. After soaking and mangling with a squeezing rate of 80%, after leaving it in superheated steam at 120℃ for 10 minutes,
Washed with methanol. The amount of kraft polymer is
The result of polymerization measurement was 140 μg/cm ² . No increase in viscosity within the graft polymerization reaction system was observed, and the resulting fabric with the graft polymerization layer had good double-sided water repellency that withstood a durability test of 50 washes.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the relationship between the amount of radically polymerizable active sites and the amount of electrical energy processed when a high-density polyethylene film is subjected to plasma treatment.

Claims (1)

[Scope of Claims] 1. At least one side of a base material made of a polymeric substance is heated under a gas pressure of 0.01 mmHg or more and 20 mmHg or less that does not contain oxygen gas and is capable of forming radically polymerizable active sites, using electrical energy of 1 watt/second/ cm2 ^or more
After low-temperature plasma treatment of 2000 Watts/ ^cm2 or less, expose it to oxygen gas or a mixed gas containing oxygen gas, or expose it to a temperature of 0.01mmHg or more for 20mm.
Under gas pressure containing oxygen gas of Hg or less, electrical energy 1 watts/cm ² or more 2000 watts/s/cm2
The base material is subjected to low temperature plasma treatment at a temperature of 10 ^-11 cm2 ^or less.
mol/ ^cm2 or more and ^10-8 mol/ ^cm2 or less of radically polymerizable active points are formed, and the base material on which the active points are formed is treated with one or more radically polymerizable active sites of 0.1% or more and 90% or less. By bringing the monomer dispersion into contact with a 0.0001% to 1% transition metal salt dispersion, or a mixed dispersion of the monomer and the transition metal salt, and heating at room temperature or heating, the substrate is A surface modification method characterized by forming an apparent graft polymerized layer of the monomer on the surface. 2. The surface modification method according to claim 1, wherein the base material made of a polymeric substance is in the form of a sheet or fiber. 3 Claims 1 and 2, wherein the base material made of a polymeric substance is polyethylene terephthalate.
The surface modification method according to any one of the above. 4. The surface modification method according to any one of claims 1, 2, and 3, wherein the base material made of a polymeric substance is a base material that has been subjected to dyeing processing, resin processing, etc. . 5. The surface modification method according to any one of claims 1 to 4, wherein the low-temperature plasma treatment is performed with a non-grounded electrode insulated from the can body. 6 The apparent graft polymerization layer of the monomer is 90%
The surface modification method according to any one of claims 1 to 5, characterized by comprising the following homopolymer having good durability. 7. The surface modification according to any one of claims 1 to 6, wherein the radically polymerizable monomer dispersion comprises an aqueous medium containing a water-insoluble monomer and an emulsifier. quality law. 8. Before or after contacting the base material with a radically polymerizable monomer dispersion or transition metal salt dispersion, or during the reaction, an inert gas is introduced into the dispersion to remove oxygen. A surface modification method according to any one of claims 1 to 7. 9. Before exposing the base material on which radically polymerizable active sites have been formed to a radically polymerizable monomer dispersion or transition metal salt dispersion, the surface of the base material must be vacuum degassed or exposed to high pressure inert gas in advance. 9. The surface modification method according to any one of claims 1 to 8, characterized in that cleaning is carried out by wiping. 10 In the graft polymerization reaction product of the monomers formed on the surface of the base material, homopolymers with poor durability and unreacted monomers are removed by chemical or physical methods.
The surface modification method according to any one of claims 1 to 9, characterized in that the surface modification method comprises removing.