KR101604858B1 - Method for Plating of Non-woven Fabric using Continuous Process of Electroless and Electrolysis Plating - Google Patents

Abstract

The present invention relates to an electroless and electrolytic continuous process metal (copper and nickel, or nickel and nickel) plating process of a nonwoven fabric and a nonwoven fabric plated by the above method. The present invention can produce a metal-plated nonwoven fabric having a small thickness and a high conductivity by filling a space with metal ions formed by electroless plating of copper or nickel for a short period of time by nickel electroplating. The composition of the plating solution can be changed or the plating rate can be adjusted to obtain a desired conductivity and a line can be formed that can be combined with copper and nickel, nickel and nickel, single nickel or single copper plating. It also makes it possible to produce highly conductive nonwoven fabrics which are not only different from those of electroless plating but different in plating thickness.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of plating a nonwoven fabric using a continuous process of electroless plating and electrolytic plating,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonwoven fabric plating method using a continuous process of electroless plating and electrolytic plating and a nonwoven fabric plated by the above method and more particularly to a method of plating a nonwoven fabric by increasing the bonding force between a metal surface- To a metal-coated nonwoven fabric having improved conductivity.

Carbon fiber reinforced composite materials, which have been rapidly developed with the development of aviation and space industry, are used today in various fields such as electric and electronic materials, civil engineering, building materials, automobiles, ships, military equipment, It is one of the advanced materials.

However, recently, carbon fiber reinforced composite materials have been used very limitedly in automobile electrical equipment and device housing for communication, which must simultaneously realize mechanical properties and electromagnetic wave shielding performance due to low conductivity, which is a disadvantage.

Carbon fiber, carbon black, CNT, TiO ₂ , nickel coated graphite, and the like are used as a filler for implementing an electromagnetic wave shielding function in a polymer composite material in order to overcome this problem. And recently introduced graphene have been developed to develop polymer composite materials having electromagnetic wave shielding efficiency. However, they have many problems in commercialization due to problems of dispersion and deterioration of mechanical properties. And, it is experiencing many trial and error because of price problem and mechanical property.

On the other hand, when the electroless or electrolytic surface treatment process, that is, the process of separating and treating each step separately after reprocessing, does not shorten the process time, has no price competitiveness, and can not simplify the production facility.

In order to increase the bonding force between the carbon fiber and the metal, a CVD process or a sputtering process has been used before, which has many problems because it is not cost competitive due to high production cost.

In addition, the electroless carbon fiber plating method is limited to a part that increases the conductivity to the carbon fiber by containing the phosphorus component due to the chemical ionic bonding. In the case of electrolytic plating, the conductivity can be increased, but the carbon fiber filaments are uniformly It is not suitable as a composite material in which the role of each filament is important because plating is not performed. Plated carbon fiber produced by electrolytic plating has a lot of fluffs and many filament disconnection phenomena, so it is limited to use as a composite material in which the plating state of the product must be maintained.

In the case of the hybrid type of the continuous process developed in the present invention, all the filaments of the carbon fiber are plated through the electroless plating, and when the chemical reagent is completely removed after the electrolysis, And it is found that a thin plated layer is formed between the metals in spite of a short electrolytic plating time, and the conductivity is improved sharply while being thin, so that it is very suitable for use as a composite material.

In the case of the conventional production, it is very difficult to control the conductivity by adjusting the thickness of the plating of the product.

However, in the case of the hybrid type in the continuous process developed in the present invention, since the electroless and electrolysis are continuously performed in a single production facility, it is possible to produce a competitive product with ease in cost and easy control, Lt; / RTI >

Numerous papers and patent documents are referenced and cited throughout this specification. The disclosures of the cited papers and patent documents are incorporated herein by reference in their entirety to better understand the state of the art to which the present invention pertains and the content of the present invention.

The present inventors have sought to develop a method for producing a metal-plated fibrous nonwoven fabric having excellent economy and conductivity. As a result, when electroless and electrolytic surface treatment processes are continuously adopted, advantages such as shortening of process time, price competitiveness, and simplification of production facilities are more advantageous than the conventional electroless or electrolytic surface treatment process , And it is confirmed that it is not only excellent in conductivity but also in production cost because it is densely plated between metal structures than the product by the former method.

Accordingly, an object of the present invention is to provide a non-woven metal (copper and nickel) plating method in an electroless and electrolytic continuous process.

Another object of the present invention is to provide a nonwoven metal (nickel and nickel) plating method in an electroless and electrolytic continuous process.

It is still another object of the present invention to provide a metal (copper and nickel) plated nonwoven fabric by the above-described method of the present invention.

Another object of the present invention is to provide a metal (nickel and nickel) plated nonwoven fabric by the above-described method of the present invention.

Other objects and advantages of the present invention will become more apparent from the following detailed description of the invention, claims and drawings.

According to one aspect of the present invention, there is provided a method of electroless and electrolytic continuous metal plating of a non-woven fabric comprising the steps of:

(a) The nonwoven fabric is treated with 2.5-5.5 g / l of Cu ion, 20-55 g / l of EDTA, 2.5-4.5 g / l of formaldehyde, 2-6 g of TEA (triethanolamine) based on the volume of pure water an electroless plating solution containing 8-12 ml / l of NaOH at 25% concentration and 0.008-0.15 g / l of 2,2'-bipyridine at pH 12-13 and a temperature of 36-45 ° C And plating copper on the nonwoven fabric for 6 to 10 minutes; And

(b) the copper-plated nonwoven fabric of step (a) comprises 280-320 g / l Ni (NH ₂ SO ₃ ) ₂ , 15-25 g / l NiCl ₂ and 35-45 g / l H ₃ BO ₃ And plating the nickel-plated non-woven fabric for 1-3 minutes by passing through an electrolytic plating solution having a pH of 4.0 to 4.2 and a temperature of 50 to 60 ° C.

According to another aspect of the present invention, the present invention provides a method of electroless and electrolytic continuous metal plating of a non-woven fabric comprising the steps of:

(a) The nonwoven fabric is impregnated with 5-7 g / l Ni ions, NaH ₂ PO ₂ 20-30 g / l Na ₃ C ₆ H ₅ O ₇ 20-30 g / l and potassium thiosulfate 0.0005 g-0.001 g / l, pH 8.5-9.5 and temperature 30-35 ° C And plating nickel on the nonwoven fabric for 6-10 minutes; And

(b) the copper-plated nonwoven fabric of step (a) comprises 280-320 g / l Ni (NH ₂ SO ₃ ) ₂ , 15-25 g / l NiCl ₂ and 35-45 g / l H ₃ BO ₃ And plating nickel on the nickel plated nonwoven fabric for 1-3 minutes through an electrolytic plating solution having a pH of 4.0-4.2 and a temperature of 50-55 ° C.

The inventors of the present invention have made extensive efforts to develop a method for producing a metal-plated fibrous nonwoven fabric having excellent economy and conductivity. As a result, when a method of continuously conducting electroless and electrolytic surface treatment processes is adopted, It has advantages such as shortening of process time, cost competitiveness, simplification of production facilities, etc. than the case of carrying out only the treatment process, and it is confirmed that the production cost is low Respectively.

The method of the present invention is characterized in that a fiber nonwoven fabric is surface-treated by a non-oxidative method to primarily electrolytically (nickel or plated) after electroless plating (copper or nickel) It is possible to produce a high-performance nonwoven fabric capable of continuous processing and having a relatively high conductivity.

The method of the present invention proceeds in a manner that is followed by electroless copper plating, or electroless nickel plating, followed by electrolytic plating.

The method of the present invention can be applied to a nonwoven fabric by various known production methods, and can be applied to, for example, a dry nonwoven fabric, a wet nonwoven fabric or a spunbond nonwoven fabric. According to one embodiment of the present invention, the method of the present invention can be applied to a carbon fiber nonwoven fabric or a PET nonwoven fabric as a wet nonwoven fabric. Methods of making the dry, nonwoven or spunbond nonwoven fabrics as described above are well known in the art and are described in Korean Patent Publication Nos. 10-2012-0121079, 101049623, 101133851, Korean Patent No. 101156844 is inserted as a reference.

 The plating method of the present invention can be applied to various kinds of known nonwoven fabrics and can be applied to various kinds of known nonwoven fabrics such as carbon fiber, polyester fiber, glass fiber, aramid fiber, ceramic fiber, metal fiber, polyimide fiber, polybenzoxazole fiber, Or a nonwoven fabric made of mixed fibers thereof.

The polyester fiber may be a polyester fiber such as polyethylene terephthalate (PET), polyglycolide (PGA), polylactic acid (PLA), polycaprolactone (PCL), polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PEA), polybutylene succinate (PBS), poly (3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), and Vectran.

According to one embodiment of the present invention, the method of the present invention can be applied to carbon fiber nonwoven fabric or PET fiber nonwoven fabric.

On the other hand, the nonwoven fabric to which the method of the present invention is applied can be produced by mixing the second fibers as the reinforcing fibers with the above-mentioned fibers (referred to as first fibers). The reinforcing fiber is a low melting fiber or a low melting filament, for example, L / M polyester fiber (LMP) can be used as a material for increasing the strength of the nonwoven fabric. The low melting point polyester fiber has a melting point lower than the melting point of general polyester of 255 DEG C and is used for heat fusion purposes.

According to the present invention, the low melting point fiber as the second fiber is L / M polyethylene terephthalate (low melting PET). Since L / M polyethylene terephthalate has a relatively low melting point, it melts when heated to about 100 캜 and is mixed with the first fiber, thereby increasing the strength of the entire nonwoven fabric.

The method of electroless and electrolytic continuous metal plating of a non-woven fabric of the present invention is for producing a metal-plated nonwoven fabric finally and has the same meaning as the method of producing a metal-plated nonwoven fabric by electroless and electrolytic continuous process Lt; / RTI >

Hereinafter, the method of the present invention for producing a metal-plated nonwoven fabric by an electroless and electrolytic continuous process will be described step by step as follows:

(a) Electroless plating process

First, the non-woven fabric is electroless-plated with metal.

In one embodiment, when the carbon fiber nonwoven fabric is plated with copper, the electroless plating solution includes pure water, a copper metal salt, a complexing agent, a reducing agent, a stabilizer, and a pH adjusting agent.

The copper metal salt contained in the electroless plating solution supplies copper ions for imparting conductivity to the carbon fiber. Formaldehyde is used as a reducing agent. EDTA as a complexing agent, TEA (triethanolamine) and 2,2'-bis Bipiridine was used as a buffer and NaOH (25%) was used as a pH controller.

As can be seen from the examples, although the plating rate was increased as the concentration of formaldehyde and NaOH, which are the reducing agents included in the electroless plating solution, was increased, the lifetime of the plating solution was shortened. The content of modulator was adopted.

On the other hand, as clearly shown in the examples, when the content of copper ion and complexing agent increased in the same ratio, the plating rate and liquid stability test were conducted by controlling the content of reducing agent. As a result, the copper ion and the concentration of formaldehyde, It is possible to adjust the plating speed and the thickness of the plating layer by adjusting the thickness of the plating layer and adjust the specific gravity, strength, elastic modulus and strain by adjusting the thickness of the plating layer. In the present invention, the thicker the plating layer, The strength, the modulus of elasticity, and the strain are lowered. Therefore, the electrolytic plating is performed together with the adjustment of the concentration of copper ion and formaldehyde as a reducing agent to improve the conductivity at a thin thickness, This is why we adopted the continuous process.

According to an embodiment of the present invention, the electroless plating step of the step (a) comprises the steps of: providing the nonwoven fabric with 4.5-5.5 g / l of Cu ion, 45-55 g / l of EDTA, 3.5-4.5 g / l of formaldehyde, 4-6 g / l of TEA (triethanolamine), 8-12 ml / l of 25% NaOH and 0.01-0.15 g / l of 2,2'-bipyridine , And is passed through an electroless plating solution having a pH of 12-13 and a temperature of 40-45 ° C, and copper is plated on the nonwoven fabric for 6-10 minutes.

In another embodiment, when nickel is plated on the nonwoven fabric, the electroless plating solution includes pure water, a nickel metal salt, a pH buffer, a reducing agent, and a stabilizer.

The nickel metal salt included in the electroless plating solution supplies nickel ions for imparting conductivity to the nonwoven fabric. NaH ₂ PO ₂ is used as a reducing agent, potassium thiosulfate as a stabilizer, and Na ₃ C ₆ H ₅ O ₇ can be used.

Then, electroless plating is of a three-stage water washing, and the washing with water after the plating, the third three-stage washing with water mixed with H ₂ SO ₄ 1-2%. This is a means to preserve the pH of the electrolytic plating bath and to activate the surface of the electrolessly plated carbon fiber.

(b) Electroplating process

After step (a), nickel or nickel is electroless plated on the copper or nickel electroless plated nonwoven fabric.

One of the features of the present invention is that the electroless plating process is performed and then the nickel electroplating process is performed to improve the electrical conductivity of the fiber or the nonwoven fabric.

The electrolytic plating solution for carrying out the electrolytic plating process includes Ni (NH ₂ SO ₃ ) ₂ and NiCl ₂ and H ₃ BO ₃ as a pH buffer.

As clearly shown in the examples, the electric resistance value was reduced by about 32-37 times as compared with the non-plated carbon fiber through the electroless and electrolytic continuous process, and the electrical conductivity was improved by about twice as compared with the comparative example . As a result, it can be seen that the electric conductivity is improved even in the case of nonwoven fabric made of carbon fiber.

It is considered that the electroconductivity is improved by performing the Ni electroplating in a short time after the electroless plating and the voids of copper or nickel.

According to an embodiment of the present invention, the electrolytic plating process of step (c) is performed by applying a constant voltage (CV) of 5-15 volts.

In the case of electroless copper plating and continuous electrolytic nickel plating, the electrolytic plating process is performed by applying a constant voltage (CV) of 5-10 volts, more preferably by applying a voltage of 6-8 volts.

In the continuous process of electroless nickel plating and electrolytic nickel plating, the electroplating process is performed by applying a constant voltage (CV) of 10-15 volts.

The advantage of electroless and electrolytic plating is that it has excellent electrical conductivity, is effective in adhesion and ductility, and has an electrolytic metal attached to the space of the metal formed by electroless plating to form an alloy layer having a thin thickness and an excellent conductivity. In addition, it has an effect of enabling uniform plating of fibers or nonwoven fabrics.

Electrolytic plating is carried out continuously after electroless plating (copper or nickel), and a nonwoven fabric is placed in the bath, and a voltage is applied to produce a product in which electrolytic ions are bonded to the pores formed by electroless plating, .

According to the present invention, the nonwoven fabric of step (a) is pre-treated by a method comprising the following steps before carrying out step (a):

(I) passing the nonwoven fabric through an aqueous solution containing a surfactant, an organic solvent and a nonionic surfactant to degrease and soften the nonwoven fabric;

(Ii) the resultant nonwoven fabric of step (i) is treated with sodium bisulfite (NaHSO ₃ ), sulfuric acid (H ₂ SO ₄ ), ammonium persulfate (NH ₄ ) ₂ S ₂ O ₈ ) Passing an aqueous solution containing pure water to perform an etching process for neutralizing, cleaning and conditioning;

(Iii) The resultant nonwoven fabric of step (ii) is treated with PdCl ₂ Passing the solution through an aqueous solution to perform a sensitizing process; And

(Iv) passing the resultant nonwoven fabric of step (iii) through an aqueous solution of sulfuric acid (H ₂ SO ₄ ) to perform an activating process.

(I) degreasing and softening of carbon fibers

In the method of the present invention, the pretreatment of the nonwoven fabric is carried out by first passing the carbon fiber through an aqueous solution containing a surfactant, an organic solvent and a nonionic surfactant to degrease and soften the nonwoven fabric.

The aqueous solution containing the surfactant, the organic solvent and the nonionic surfactant performs a degreasing action to remove the epoxy or urethane which is dispersed in the carbon fiber, and at the same time, softens the surface of the fiber by swelling.

According to the present invention, the aqueous solution of step (i) is prepared by mixing 15 to 35% by weight of a solution obtained by mixing pure water and NaOH in a weight ratio of 40-49: 1-10 as a surfactant, adding diethyl propanediol diethyl propanediol, 5-15% by weight of dipropylene glycol methyl ether, and 400-600 ppm of non-ionic surfactant, and even more preferably, 20 to 30% by weight of a solution of pure water and NaOH in a weight ratio of 45 to 48: 2-5, 58 to 72% by weight of diethyl propanediol as an organic solvent and dipropylene glycol methyl ether ether of from 8 to 12% by weight, and from 450 to 550 ppm of nonionic surfactant.

The nonionic surfactant includes various nonionic surfactants known in the art, but is preferably selected from the group consisting of ethoxylated linear alcohol, ethoxylated linear alkyl-phenol, Ethoxylated linear thiol, and more preferably ethoxylated linear alcohol.

According to a further preferred embodiment of the present invention, step (i) is carried out at a temperature of 40-60 ° C for 1-5 minutes, more preferably at a temperature of 45-55 ° C for 1-3 minutes.

(Ii) etching process

Next, the strong alkaline components are neutralized, and an etching process is performed to assist the cleaning action and the conditioning action for the next sensitizing process.

The aqueous solution for the etching process includes sodium bisulfite (NaHSO ₃ ), sulfuric acid (H ₂ SO ₄ ), ammonium persulfate (NH ₄ ) ₂ S ₂ O ₈ ) and pure water do.

According to the present invention, the aqueous solution of step (ii) may contain 0.1-10% by weight of sodium bisulfite (NaHSO ₃ ), 0.1-3% by weight of sulfuric acid (H ₂ SO ₄ ), ammonium persulfate NH ₄ ) ₂ S ₂ O ₈ ) and 62-94.8 wt% pure water, more preferably 0.8-2 wt% sodium bisulfite (NaHSO ₃ ) 0.3-1% by weight of sulfuric acid (H ₂ SO ₄ ), 10-20% by weight of ammonium persulfate (NH ₄ ) ₂ S ₂ O ₈ and 77-88.9% by weight of pure water.

According to one embodiment of the present invention, step (ii) is carried out at a temperature of 20-25 ° C for 1-5 minutes, more preferably at a temperature of 20-25 ° C for 1-3 minutes.

(Ⅲ) Sensi palletizing (sensitizing) process

Then, the resultant nonwoven fabric of step (ii) was washed with PdCl₂ And passing the solution through an aqueous solution to perform a sensitizing process.

The sensing process is for adsorbing metal ions on the surface of the surface-modified fiber or nonwoven fabric.

More preferably PdCl ₂ The concentration of the aqueous solution is 10-30%, more preferably 15-25%.

According to one embodiment of the present invention, step (iii) is carried out at a temperature of 20 to 40 DEG C for 1 to 5 minutes, more preferably at a temperature of 25 to 35 DEG C for 1 to 3 minutes.

(Ⅳ) activation (activating) process

Then, the resultant nonwoven fabric of step (iii) is passed through an aqueous solution of sulfuric acid (H ₂ SO ₄ ) to perform an activating process.

Although the activation process is described as being performed after the sensing process, it is also within the scope of the present invention to perform the activation process together with the sensitizing process.

The activation process is performed to remove the colloidal Sn to prevent oxidation of Pd.

More preferably sulfuric acid (H ₂ SO ₄₎ concentration of the aqueous solution is 5-15%.

According to a more preferred embodiment of the present invention, the step (iv) is carried out at a temperature of 40-60 ° C for 1-5 minutes, more preferably at a temperature of 45-55 ° C for 1-3 minutes.

In this way, the nonwoven fabric can be pretreated, and the pre-treated nonwoven fabric can be plated with metals such as copper and nickel, and nickel and nickel by an electroless and electrolytic continuous process. On the other hand, the pretreatment process is described after the fabrication of the nonwoven fabric, but the pretreatment process may be applied to the fiber itself before the fabrication of the nonwoven fabric.

According to another aspect of the present invention, there is provided a metal (copper and nickel) plated nonwoven fabric produced by the above-described method of the present invention.

According to another aspect of the present invention, the present invention provides a metal (nickel and nickel) plated nonwoven fabric produced by the method of the present invention described above.

Since the copper and nickel or nickel and nickel plated nonwoven fabric of the present invention is produced by the method of manufacturing the metal-plated carbon fiber by the electroless and electrolytic continuous process of the present invention described above, In order to avoid the excessive complexity of the specification according to the description, the description is omitted.

The features and advantages of the present invention are summarized as follows:

(a) The plating method used in the present invention allows a continuous process, and stable treatment can be performed, and a copper or nickel alloy or a nickel-nickel metal is introduced into the surface of the carbon fiber, so that the fiber or the nonwoven fabric has high electrical conductivity.

(b) There is no phenomenon that the carbon fiber, copper-nickel plating or nickel-nickel plating is peeled off during the production of the composite material, and thus the same conductivity is maintained even when the composite material is finished. It is possible to reduce the process and cost of adding a conductive filler to increase the electrical conductivity, and there is no problem in mechanical properties, which is one of the important characteristics of the composite material.

1 shows an apparatus for surface treatment of a nonwoven fabric according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these embodiments are only for describing the present invention in more detail and that the scope of the present invention is not limited by these embodiments in accordance with the gist of the present invention .

Example

Throughout this specification, "%" used to denote the concentration of a particular substance is intended to include solids / solids (wt / wt), solid / liquid (wt / The liquid / liquid is (vol / vol)%.

Example  One: Carbon fiber  Nonwoven and PET  Fabrication of nonwoven fabric

Carbon fiber  Non-woven

The carbon fiber nonwoven fabric was made in the form of a wet laid.

First, carbon fibers (12K, purchased from Toray, Hyosung or TK) were cut to a length of about 6 mm, and then the cut carbon fiber chops were dispersed in water. The dispersed carbon fibers were floated in water to form a layer having a certain thickness in water through left and right vibrations. Next, the carbon fiber layer was taken out, dried, and then pressed on a roller to produce a nonwoven fabric.

Meanwhile, in order to increase the strength of the nonwoven fabric, a nonwoven fabric can be produced by dispersing L / M PET (low melting PET chop 6 mm) together with carbon fiber 6 mm chop in water and pressing it at about 100 ° C on a heating roller . Since the L / M PET has a melting property at about 100 ° C, the nonwoven fabric produced by mixing a small amount of the carbon fiber with the carbon fiber after heating and pressing is increased in strength as compared with a nonwoven fabric made of 100% carbon fiber.

PET  Non-woven

The PET nonwoven fabric was produced in the form of a wet laid and manufactured in the same manner as in the above-described method of producing a carbon fiber nonwoven fabric, except that PET instead of carbon fiber (purchased from TEIJIN, Japan) 6 mm chop was used. Meanwhile, as described above, to increase the strength of the PET nonwoven fabric, a certain amount of L / M PET may be mixed to produce a nonwoven fabric.

Carbon fiber  Nonwoven and PET  Pretreatment of nonwoven fabric

1) degreasing and softening process

First, an epoxy or urethane which is sized by carbon fiber is removed by using an organic solvent, and at the same time, a process of softening the fiber surface by swelling is performed.

25% by weight of a solution obtained by mixing pure water and NaOH in a weight ratio of 47: 3 as a surfactant, 65% by weight of diethyl propanediol as an organic solvent, and 10% by weight of dipropylene glycol methyl ether 10 The carbon fiber nonwoven fabric or the PET nonwoven fabric of Example 1 was passed through a pretreatment tank containing 10% by weight of a nonionic surfactant (non-ionic surfactant, low foam) and 5% by weight of an ethoxylated linear alcohol, And a softening process. The degreasing and softening process was carried out at a temperature of 50 DEG C for 2 minutes.

2) Etching process

The strong alkaline components of NaOH are neutralized by using sulfuric acid (H ₂ SO ₄ ), and it is possible to reduce the burden on the next step of sensitizing process by using ammonium persulfate ((NH ₄ ) ₂ S ₂ O ₈ ) An etching process was carried out in order to facilitate the cleaning action and to perform a conditioning action to enhance the adsorption of palladium.

Specifically, 1 wt% of sodium bisulfite (NaHSO ₃ ), 0.5 wt% of sulfuric acid (H ₂ SO ₄ ), 15 wt% of ammonium persulfate (NH ₄ ) ₂ S ₂ O ₈ , and 83.5% by weight of pure water was passed through a nonwoven fabric subjected to a degreasing and softening process to perform an etching process for neutralizing, cleaning and conditioning. The etching process was performed at a temperature of 20-25 ° C for 2 minutes.

3) Sensing process (catalyst addition process)

The nonwoven fabric subjected to the etching process was treated with PdCl ₂ at a concentration of 20% at a temperature of 30 ° C for 2 minutes to carry out a sensing process. The sensing process is carried out to adsorb metal ions on the surface of the surface-modified carbon fiber or PET.

4) Activating process

In order to prevent the oxidation of Pd, sulfuric acid (H ₂ SO ₄ ) at a concentration of 10% at a temperature of 50 ° C was treated with a nonwoven fabric for 2 minutes in order to prevent oxidation of Pd in a process carried out in conjunction with a sensitizing process .

The nonwoven fabric was pretreated by the above process, and the carbon fiber nonwoven fabric and PET nonwoven fabric were pretreated by the same process.

Example  2 and 3: Electroless  And a copper and nickel plated Carbon fiber

Carbon fiber (12K, purchased from Toray) pretreated with the process of Example 1 using the plating apparatus shown in Fig. 1 below and carbon fiber 12K pretreated in Example 1 (TK) were subjected to electroless copper plating under the composition and conditions shown in the following Table 1 and subjected to electrolytic nickel plating process under the composition and conditions of the following Table 2 in a continuous process to produce copper and nickel-plated carbon fibers , Which were used in Examples 2 and 3, respectively: The content of the plating solution component described in the following examples is based on 1 L of pure water.

Electroless copper plating solution - ingredient Content (Conditions) Metal salt Cu ion 3 g / l Complexing agent EDTA 30 g / l reducing agent Formaldehyde 3.0 g / l stabilizator TEA (triethanolamine) 3 g / l 2,2'-bipyridine 0.01 g / l pH adjusting agent NaOH (25%) 12 ml / l Temperature 38 ° C pH 12.5 Processing time 6 min

Ni electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 300 g / l NiCl ₂ 20 g / l pH buffer H ₃ BO ₃ 40 g / l Temperature 55 ° C pH 4.2 Processing time 1 min

Example  4: Electroless  And copper and nickel plated carbon fibers in an electrolytic continuous plating process

The carbon fiber pretreated with the process of Example 1 was subjected to electroless copper plating under the composition and conditions shown in Table 3 below using the plating apparatus of FIG. 1, An electrolytic nickel plating process was performed to produce carbon fiber coated with copper and nickel:

Electroless copper plating solution - ingredient Content (Conditions) Metal salt Cu ion 2.5-3.5 g / l Complexing agent EDTA 25-35 g / l reducing agent Formaldehyde 2.5-3.5 g / l stabilizator TEA (triethanolamine) 2-3 g / l 2,2'-bipyridine 0.008-0.01 g / l pH adjusting agent NaOH (25%) 8-12 ml / l Temperature 36-40 ° C pH 12-13 Processing time 6-10 min

Ni electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 280-320 g / l NiCl ₂ 15-25 g / l pH buffer H ₃ BO ₃ 35-45 g / l Temperature 50-55 ℃ pH 4.0-4.2 Processing time 1-3 min

In the case of electrolytic plating, a constant voltage (CV) of 5-10 volts was added to the electrolytic nickel bath. The metal plate used as the anode was a Ni metal plate or a Ni ball.

Example  5: Electroless  And copper and nickel plated carbon fibers in an electrolytic continuous plating process

The carbon fibers pretreated with the process of Example 1 were subjected to electroless copper plating under the composition and conditions shown in Table 5 below using the plating apparatus shown in Fig. An electrolytic nickel plating process was performed to produce carbon fiber coated with copper and nickel:

Electroless copper plating solution - ingredient Content (Conditions) Metal salt Cu ion 4.5-5.5 g / l Complexing agent EDTA 45-55 g / l reducing agent Formaldehyde 3.5-4.5 g / l stabilizator TEA (triethanolamine) 4-6 g / l 2, 2'-bipyridine 0.01-0.15 g / l pH adjusting agent NaOH (25%) 8-12 ml / l Temperature 40-45 ℃ pH 12-13 Processing time 6-10 min

Ni electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 280-320 g / l NiCl ₂ 15-25 g / l pH buffer H ₃ BO ₃ 35-45 g / l Temperature 50-55 ℃ pH 4.0-4.2 Processing time 1-3 min

In the case of electrolytic plating, a constant voltage (CV) of 5-10 volts was added to the electrolytic nickel bath. The metal plate used as the anode was a Ni metal plate or a Ni ball.

Example  6: Electroless  And nickel and nickel plated carbon fibers in an electrolytic continuous plating process

The carbon fibers pretreated with the process of Example 1 were subjected to electroless nickel plating under the composition and conditions shown in Table 7 below using the plating apparatus shown in FIG. An electrolytic nickel plating process was performed to produce nickel-plated carbon fibers:

Electroless nickel plating solution - ingredient Content (Conditions) Metal salt Ni ion 5-7 g / l reducing agent NaH ₂ PO ₂ 20-30 g / l pH buffer Na ₃ C ₆ H ₅ O ₇ 20-30 g / l stabilizator Potassium thiosulfate 0.0005 g-0.001 g / l Temperature 30-35 ℃ pH 8.5-9.5 Processing time 6-10 min

Ni electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 280-320 g / l NiCl ₂ 15-25 g / l pH buffer H ₃ BO ₃ 35-45 g / l Temperature 50-55 ℃ pH 4.0-4.2 Processing time 1-3 min

In the case of electrolytic plating, a constant voltage (CV) of 10-15 volts was added to the electrolytic nickel bath. The metal plate used as the anode was a Ni metal plate or a Ni ball.

Experimental Example  1: Change in current density and the change of the plated carbon fiber Line resistance value  Measure

In the composition and conditions for preparing the copper and nickel-plated carbon fibers of Example 4, optimization conditions of electroless and electrolytic plating were set through controlling the concentration of NaOH to adjust the pH and the concentration of HCHO to help the reduction reaction of Cu .

(A) change in the carbon fiber while changing the concentration of 25% NaOH to 8, 9, 10, 11 and 12 ml / l and the HCHO to 2.5, 2.7, 2.9, 3.1 and 3.3 g / (Ω / 30 cm) of the finally obtained products (copper and nickel-plated carbon fibers), and the results are summarized in Table 9 below. The results are summarized in Table 9, and a constant voltage (CV) 7 Volt, and the other constant conditions are summarized in Tables 10 and 11 below:

HCHO NaOH Current density (A) Resistance (Ω / 30cm) Period of use of plating solution 2.5 8 100 0.8 Use 10 turn 9 110 0.6 10 120 0.4 11 130 0.3 12 140 0.2 2.7 8 110 0.7 Use 8 turn 9 120 0.6 10 130 0.5 11 140 0.3 12 150 0.2 2.9 8 120 0.6 Use 6 turns 9 130 0.5 10 140 0.4 11 150 0.3 12 160 0.2 3.1 8 130 0.6 Use 4 turn 9 140 0.5 10 150 0.4 11 160 0.3 12 170 0.2 3.3 8 140 0.5 Use 2 turns 9 150 0.4 10 160 0.3 11 170 0.2 12 180 0.1

In Table 9, 1 turn represents the amount of one electroless copper plating bath.

Electroless copper plating solution - ingredient Content (Conditions) Metal salt Cu ion 3 g / l Complexing agent EDTA 30 g / l reducing agent Formaldehyde (HCHO) 2.5-3.3 g / l stabilizator TEA (triethanolamine) 3 g / l 2, 2'-bipyridine 0.10 g / l pH adjusting agent NaOH (25%) 8-12 ml / l Temperature 37 ℃ pH 12.5 Processing time 6 min

Electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 300 g / l NiCl ₂ 20 g / l pH buffer H ₃ BO ₃ 40 g / l Temperature 55 ° C pH 4.2 Processing time 1 min Constant voltage (Cv) 7 V

As can be seen from Table 9, although the plating rate was increased as the amount of the reducing agent and NaOH was increased, it was found that the lifetime of the plating solution was shortened. It may be desirable to keep the amount of reducing agent at minimum (2.5-3.0 g / l) and work up to the maximum amount of NaOH.

Experimental Example  2: Plating speed and liquid stability test

The plating rate and liquid stability test through the control of copper ion and complexing agent (EDTA) showed that when the copper ions and complexing agent were rising at the same rate, the amount of reducing agent was controlled (Table 12) , And other constant ingredients and conditions are summarized in Tables 13 and 14 below:

Metal salt (Cu) Reducing agent (HCHO) Complexing agent (EDTA) NaOH Plating thickness (탆) 2.5 2.5 25 12 0.2-0.3 3.5 3.0 35 0.3-0.5 4.5 3.5 45 0.4-0.6 5.5 4 55 0.5-0.8

Electroless copper plating solution - ingredient Content (Conditions) Metal salt Cu ion 2.5-5.5 g / l Complexing agent EDTA 25-55 g / l reducing agent Formaldehyde 2.5-4 g / l stabilizator TEA (triethanolamine) 3 g / l 2,2'-bipyridine 0.01 g / l pH adjusting agent NaOH (25%) 12 ml / l Temperature 37 ℃ pH 12.5 Processing time 6 min

Electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 300 g / l NiCl ₂ 20 g / l pH buffer H ₃ BO ₃ 40 g / l Temperature 55 ° C pH 4.2 Processing time 1 min C.V 7 V

As shown in Table 12, it was confirmed that the higher the concentration of copper and the concentration of HCHO, the higher the plating speed and the higher the thickness of the plating layer (the plating thickness is 0.7 micron or more). In order to have a preferable plating thickness of 0.3 mu m for the carbon fiber, the best result was obtained at a copper ion concentration of 2.5-3.0 g / l and a HCHO concentration of 2.5-3.0 g / l or less.

As the thickness of the carbon fiber increases, the specific gravity also increases, and the strength, elastic modulus and strain are lowered. Therefore, rather than raising the plating thickness for the electroless plating, It is considered desirable to produce carbon fibers having excellent electrical conductivity.

Experimental Example  3: Comparison of physical properties and electrical conductivity

In the following Table 15, the nickel-plated carbon fibers of Examples 2 and 3 and the nickel-plated carbon fibers produced by the commercially available electroless plating process were compared with each other by comparing the properties such as physical properties and electrical conductivity as follows:

- Comparative Example 1 Example 2 Example 3 Remarks Strand strength
(kgf / ㎟) (Range) 280 380
(367 to 405) 338
(325 to 353) - Elastic modulus (tons / mm2) 22.0 20.0 22.5 - Strain (%) 1.2 1.9 1.5 - Specific gravity (g / cm3) 2.70 2.7277 2.7894 - Diameter (㎛) 7.5 7.828 7.705 - Tex (tex)
(Fiber thickness) 1420 1575 1561 - Electrical resistance (Ω / m) - 0.8 0.7 - Electrical resistance (Ω cm) 7.5 × 10 ^-5 4.62 × 10 ^-5 4.05 x 10 ^-5 - General CF contrast
Electrical resistance - 32 times reduction 37 times reduction General CF:
Based on 1.50 × 10 ^-3 Ω cm Coating Thickness (nm) 250 240
(210-271) 350
(305 to 392) -

As can be seen from Table 15 above, the copper and nickel plated carbon fibers of Examples 2 and 3 had better physical properties and lower electrical resistivity values than Comparative Example 1 produced by the electroless plating process, I was able to find out.

Example  7: Electroless  And a copper and nickel plated Carbon fiber  Nonwoven and PET  Non-woven

The carbon fiber nonwoven fabric and the PET nonwoven fabric of Example 1 were subjected to electroless copper plating under the composition and conditions shown in Table 16 below using the plating apparatus shown in Fig. 1 below. An electrolytic nickel plating process was performed to produce a carbon fiber nonwoven fabric and a PET nonwoven fabric plated with copper and nickel.

Electroless copper plating solution - ingredient Content (Conditions) Metal salt Cu ion 4.5-5.5 g / l Complexing agent EDTA 45-55 g / l reducing agent Formaldehyde 3.5-4.5 g / l stabilizator TEA (triethanolamine) 4-6 g / l 2, 2'-bipyridine 0.01-0.15 g / l pH adjusting agent NaOH (25%) 8-12 ml / l Temperature 40-45 ℃ pH 12-13 Processing time 6-10 min

Ni electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 280-320 g / l NiCl ₂ 15-25 g / l pH buffer H ₃ BO ₃ 35-45 g / l Temperature 50-55 ℃ pH 4.0-4.2 Processing time 1-3 min

In the case of electrolytic plating, a constant voltage (CV) of 5-10 volts was added to the electrolytic nickel bath. The metal plate used as the anode was a Ni metal plate or a Ni ball.

Example  8: Electroless  And nickel plated by an electrolytic continuous plating process Carbon fiber  Nonwoven and PET  Non-woven

The nonwoven fabric pretreated with the process of Example 1 was subjected to electroless nickel plating with the composition and conditions shown in Table 18 below using the plating apparatus of FIG. 1, A nickel plating process was carried out to prepare a nickel-plated nonwoven fabric:

Electroless nickel plating solution - ingredient Content (Conditions) Metal salt Ni ion 5-7 g / l reducing agent NaH ₂ PO ₂ 20-30 g / l pH buffer Na ₃ C ₆ H ₅ O ₇ 20-30 g / l stabilizator Potassium thiosulfate 0.0005 g-0.001 g / l Temperature 30-35 ℃ pH 8.5-9.5 Processing time 6-10 min

Ni electrolytic plating solution - ingredient Content (Conditions) Electrolytic plating solution Nickel metal salt Ni (NH ₂ SO _{3) 2} 280-320 g / l NiCl ₂ 15-25 g / l pH buffer H ₃ BO ₃ 35-45 g / l Temperature 50-55 ℃ pH 4.0-4.2 Processing time 1-3 min

In the case of electrolytic plating, a constant voltage (CV) of 10-15 volts was added to the electrolytic nickel bath. The metal plate used as the anode was a Ni metal plate or a Ni ball.

Experimental Example  4: Electrical properties of nonwoven fabric

The electrical properties of the plated nonwoven fabrics of Examples 7 and 8 were analyzed as shown in Tables 20 and 21, respectively.

Item Configuration Before plating
Basis weight Electrical properties after copper / nickel double plating (g / m ² ) resistance
(Ω) Surface resistance
(Ω / square) Volume resistance
(Ω * cm) Electrical Conductivity (S / cm) One C / F 100% 15 2 * 10 ^-1 9.97 * 10 ^-2 3.69 * 10 ^-2 2.7 * 10 ¹ 2 C / F 80%
+ L / M PET
20% 20 3.88 * 10 ^-1 1.76 * 10 ⁰ 3.69 * 10 ^-2 2.7 * 10 ¹ 3 PET 80%
+ L / M PET 20% 5 1.79 * 10 ² 8.12 * 10 ² 1.62 * 10 ⁰ 6.15 * 10 ^-1 4 PET 60%
+ L / M PET 40% 10 6.91 * 10 ^-1 3.13 * 10 ⁰ 1.25 * 10 ^-2 7.97 * 10 ¹

Item Configuration Before plating
Basis weight Electrical properties after nickel / nickel double plating (g / m ² ) resistance
(Ω) Surface resistance
(Ω / square) Volume resistance
(Ω * cm) Electrical Conductivity (S / cm) One C / F: 70%
1.1d L / M PET: 30% 15 6.62 * 10 ^-1 3.00 * 10 ⁰ 5.70 * 10 ^-2 1.75 * 10 ¹

C / F: carbon fiber

L / M PET: Low melting point PET

PET: Polyethylene terephthalate

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the present invention. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

Claims (10)

An electroless and electrolytic continuous process of a nonwoven fabric comprising the steps of:
(a ') pre-treating a nonwoven fabric, comprising the steps of: (i) passing the nonwoven fabric through an aqueous solution containing a surfactant, an organic solvent and a nonionic surfactant to degrease and soften the nonwoven fabric; (Ii) the resultant nonwoven fabric of step (i) is treated with sodium bisulfite (NaHSO ₃ ), sulfuric acid (H ₂ SO ₄ ), ammonium persulfate (NH ₄ ) ₂ S ₂ O ₈ ) Passing an aqueous solution containing pure water to perform an etching process for neutralizing, cleaning and conditioning; (Iii) passing the resultant nonwoven fabric of step (ii) through a PdCl ₂ aqueous solution to perform a sensitizing process; And (iv) passing the resultant nonwoven fabric of step (iii) through an aqueous solution of sulfuric acid (H ₂ SO ₄ ) to perform an activating process,
(a) the nonwoven fabric of step (a ') is treated with 2.5-5.5 g / l Cu ion, 20-55 g / l EDTA, 2.5-4.5 g / l formaldehyde, TEA (Triethanolamine) 2-6 g / l, 8-12 ml / l NaOH at 25% concentration and 0.008-0.15 g / l 2,2'-bipyridine, pH 12-13 and temperature 36 Passing through an electroless plating solution at -45 占 폚 to deposit copper on the nonwoven fabric for 6 to 10 minutes; And
(b) the copper-plated nonwoven fabric of step (a) comprises 280-320 g / l Ni (NH ₂ SO ₃ ) ₂ , 15-25 g / l NiCl ₂ and 35-45 g / l H ₃ BO ₃ And plating the nickel-plated non-woven fabric for 1-3 minutes by passing through an electrolytic plating solution having a pH of 4.0 to 4.2 and a temperature of 50 to 60 ° C.
A method of metal plating in an electroless and electrolytic continuous process of a non-woven fabric comprising the steps of:
(a ') pre-treating a nonwoven fabric, comprising the steps of: (i) passing the nonwoven fabric through an aqueous solution containing a surfactant, an organic solvent and a nonionic surfactant to degrease and soften the nonwoven fabric; (Ii) the resultant nonwoven fabric of step (i) is treated with sodium bisulfite (NaHSO ₃ ), sulfuric acid (H ₂ SO ₄ ), ammonium persulfate (NH ₄ ) ₂ S ₂ O ₈ ) Passing an aqueous solution containing pure water to perform an etching process for neutralizing, cleaning and conditioning; (Iii) passing the resultant nonwoven fabric of step (ii) through a PdCl ₂ aqueous solution to perform a sensitizing process; And (iv) passing the resultant nonwoven fabric of step (iii) through an aqueous solution of sulfuric acid (H ₂ SO ₄ ) to perform an activating process,
(a) to the non-woven fabric of step (a '), based on the volume of the pure water (pure water) Ni ions _{5-7 g / l, NaH 2 PO} 2 20-30 g / l, Na 3 C 6 H 5 O ₇ 20-30 g / l potassium thiosulfate, and 0.0005 g-0.001 g / l potassium thiosulfate and passed through an electroless plating solution having a pH of 8.5-9.5 and a temperature of 30-35 ° C to electroplating nickel on the nonwoven fabric for 6-10 minutes step; And
(b) the nickel plated nonwoven fabric of step (a) comprises 280-320 g / l Ni (NH ₂ SO ₃ ) ₂ , 15-25 g / l NiCl ₂ and 35-45 g / l H ₃ BO ₃ And plating nickel on the nickel plated nonwoven fabric for 1-3 minutes through an electrolytic plating solution having a pH of 4.0-4.2 and a temperature of 50-55 ° C.
The nonwoven fabric according to any one of claims 1 to 5, wherein the nonwoven fabric is made of carbon fiber, polyester fiber, glass fiber, aramid fiber, ceramic fiber, metal fiber, polyimide fiber, polybenzoxazole fiber, natural fiber, .
The method of claim 3, wherein the polyester fiber is selected from the group consisting of polyethylene terephthalate (PET), polyglycolide (PGA), polylactic acid (PLA), polycaprolactone (PCL), polyhydroxyalkanoate Hydroxybutyrate (PHBV), polybutylene terephthalate (PBT), polybutylene terephthalate (PBT), polybutylene terephthalate (PBT), polybutylene terephthalate ), Polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN) or Vectran.
The method of claim 1, wherein the step (a) comprises: providing a nonwoven fabric with 4.5-5.5 g / l Cu ion, 45-55 g / l EDTA, 3.5-4.5 g / l formaldehyde, based on the volume of pure water , 4-6 g / l of TEA (triethanolamine), 8-12 ml / l of 25% NaOH and 0.01-0.15 g / l of 2,2'-bipyridine, Passing through an electroless plating solution at a temperature of 40-45 占 폚 and plating copper on the nonwoven fabric for 6-10 minutes.
3. The method according to claim 1 or 2, wherein the step (b) is performed by applying a constant voltage (CV) of 5-15 volts.
delete The method according to claim 1, wherein the aqueous solution of step (i) comprises 15 to 35% by weight of a solution obtained by mixing pure water and NaOH in a weight ratio of 40-49: 1-10 as a surfactant, 50 to 80% by weight of diethyl propanediol, 5 to 15% by weight of dipropylene glycol methyl ether, and 400 to 600 ppm of nonionic surfactant.
The method of claim 1, wherein the aqueous solution of step (ii) comprises 0.1-10% by weight of sodium bisulfite (NaHSO ₃ ), 0.1-3% by weight of sulfuric acid (H ₂ SO ₄ ), ammonium persulfate (NH ₄ ) ₂ S ₂ O ₈ ) and 62-94.8 wt% of pure water.
The method according to claim 1, wherein the step (i) is carried out at a temperature of 40 to 60 ° C for 1 to 5 minutes, the step (ii) is carried out at a temperature of 20 to 25 ° C for 1 to 5 minutes, ) Is carried out at a temperature of 20 to 40 ° C for 1 to 5 minutes, and the step (iv) is carried out at a temperature of 40 to 60 ° C for 1 to 5 minutes.

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