CN114829672A

CN114829672A - Avoiding unwanted plating on stent coatings for electrodeposition

Info

Publication number: CN114829672A
Application number: CN202080075679.4A
Authority: CN
Inventors: T·皮尔逊; A·希斯洛普; A·辛格; R·赫德曼
Original assignee: MacDermid Inc
Current assignee: MacDermid Inc
Priority date: 2019-10-04
Filing date: 2020-10-02
Publication date: 2022-07-29
Also published as: CA3153306A1; MX2022004084A; WO2021064417A1; EP4038218A1; GB2587662A; CA3153306C; GB201914372D0; JP2022551613A; JP7315793B2; US20230313382A1; KR20220109387A

Abstract

The invention relates to a support for supporting a part to be plated in a chromium-free acid plating process, the support having a contact surface comprising an iodine-and/or bromine-treated plastic.

Description

Avoiding unwanted plating on stent coatings for electrodeposition

The present invention relates to a support for supporting a part to be plated in a non-chromium acid plating process, a plating apparatus for use in a non-chromium acid plating process, a method of treating a support for supporting a part to be plated in a non-chromium acid plating process, a process for plating a part and the use of an iodine and/or bromine pretreatment on a support for supporting a part to be plated.

Plastic coating (POP) is a technology that has wide application in areas such as the automotive industry and shower and bath fittings. The most common substrate for plating is a copolymer of acrylonitrile, styrene, and butadiene (which is referred to as ABS). This is a two-phase plastic consisting of a hard phase of an acrylonitrile/styrene copolymer and a softer phase consisting of polybutadiene. Sometimes, ABS polymers are combined with a certain percentage of polycarbonate to make ABS/PC. To plate these parts, they are mounted on a metal support to deliver a plating current to the parts after the initial metallization stage. The metal plated stent is coated with a PVC plastisol coating to avoid the entire stent being plated.

The plating process for ABS involves a stage of etching the plastic to roughen the surface so that the surface provides good adhesion during the subsequent plating stage and is sufficiently hydrophilic to be fully wetted when immersed in an aqueous solution. After the etching stage, the non-conductive ABS initially needs to be metallized with a thin layer of nickel or copper in order to make it conductive for subsequent plating operations. This is achieved by: the plated support holding the ABS part is immersed in an aqueous solution of the catalyst (usually a palladium colloid) which deposits a thin layer of catalyst on the plastic surface. This is then used as a catalyst for an electroless nickel or copper plating process that produces a thin metal layer on the ABS component. Aqueous solutions of such catalysts are referred to as activator solutions, and plastic surfaces treated in such baths are referred to as "activated" surfaces.

The initial etching stage for plating the ABS is typically a solution of chromic and sulfuric acids that (predominantly) oxidizes the polybutadiene phase of the ABS to produce the necessary plastic roughening. The chromic acid solution is highly permeable and a portion of it is adsorbed by the stent-coated PVC plastisol material. After subsequent immersion in colloidal palladium, a portion of the colloid adheres to the PVC plastisol but is deactivated by the adsorbed chromic acid. Thus, when a stent holding an ABS component is immersed in an electroless nickel or copper plating solution, the catalyst adsorbed on the ABS component catalyzes the deposition of copper or nickel onto the component, but no nickel or copper is deposited on the stent coating because of the presence of chromic acid on the PVC plastic sol on the stent coating.

Chromic acid is a class 1 carcinogen and is under increasing legislative pressure. Chromic acid is being phased out in europe. Chromic acid is currently only available for some authorized applications, and even this limited use may be further limited to obsolete locations.

More recently, a new way of etching ABS plastics using a combination of acid and manganese (III) ions has been developed (see, for example, US9534306B2 and US10260000B2 to Pearson, the attachments of which are hereby incorporated by reference). However, manganese-based etching is not effective enough to suppress palladium colloids adhering to PVC plastisol coatings to prevent nickel or copper deposition during the chemical deposition phase of the POP process. Several patents have been created detailing compounds that can be used to treat PVC stent coatings to avoid this problem (e.g., EP3059277B1 to Noffke, US9506150B2 to Weitershaus, US9181622B2 to middleke, and applications US2015233011a1 to Herdman and US2019112712a1 to Dalbin, the attachments of which are hereby incorporated by reference). Most of the compounds currently in use are organic sulfur compounds. While these compounds are effective at preventing nickel or copper deposition during the electroless plating stage, they can cause unexpected problems during the electroplating stage. The problem is that even if no detectable nickel or copper is present on the PVC plastisol coating after immersion in the chemical process, the stent will subsequently be covered by copper during the acidic copper plating stage after the initial metallization of the ABS parts. Without wishing to be bound by theory, it is believed that this is most likely due to the reaction of copper ions with the adsorbed organic sulfur compounds on the PVC coating resulting in the formation of copper sulfide. This is a p-type semiconductor with high specific conductivity and, without being bound by theory, it is believed that this is the main reason why the plated support tends to be covered by copper. Accordingly, there is a need for an improved method for inhibiting plating on PVC stent coatings during plating of ABS and ABS/PC using processing techniques that do not involve the use of chromic acid.

WO2015/150156a1 relates to a composition and process for metallizing non-conductive plastic surfaces. WO2013/135862a2 relates to a process for metallizing a surface of a non-conductive plastic. The processes of these two documents use Iodate (IO) ₃ ^- ) The solution pretreats the plated stent. Because of the absence of reducing agent in the solution, the iodate ion remains iodate ion without the formation of iodine, i.e., I ₂ -. The effect of such a pretreatment is described as resulting in "special protection of the plastic shell of the stent from metal deposition". One problem with such processes is that it is not possible to confirm whether the stent has been pretreated because the stent has not visually changed after pretreatment. Therefore, a pre-treatment step has to be performed each time the deposition process is performed, or alternatively the risk is accepted that no pre-treatment has been performed or that pre-treatment has been consumed/made ineffective.

The present invention seeks to solve at least some of the problems associated with the prior art or at least to provide a commercially acceptable alternative solution to the prior art. In particular, the present invention aims to provide an improved support for use in a non-chromate plating process.

In a first aspect, the present invention provides a support for supporting a part to be plated in a chromium-free acid plating process, the support having a contact surface comprising iodine-treated and/or bromine-treated plastic.

The inventors have surprisingly found that during a non-chromate plating process, when a component is mounted on a support, substantially no copper or nickel may be deposited on the support during the chemical deposition stage and also substantially no deposition on the support during the subsequent electroplating stage. Without being bound by theory, it is believed that the contact surface of the support of the present invention is not significantly activated such that the contact surface is not plated in an acidic copper plating process, as opposed to an organosulfur treated support.

Although iodate-treated plastics have been described in the prior art as being resistant to metal deposition, surprisingly, iodine-and/or bromine-treated plastics also show this effect. This is because iodate and iodine are chemically very different-iodate is an ionic species (IO) ₃ ^- ) Containing a combination of an iodine atom in the +5 oxidation state with an oxygen atom, iodine being the covalent species (I) ₂ ) And contains only iodine atoms in the elemental state (oxidation state zero).

Each aspect or embodiment as defined herein may be combined with any other aspect or embodiment, unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature indicated as being preferred or advantageous.

When introducing elements of the present disclosure or the preferred embodiments thereof, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. The term "consisting of …" is intended to mean that no other elements are possible in addition to the listed elements. The term "consisting essentially of …" is intended to mean that no additional elements other than the listed elements are possible unless the additional elements do not materially affect the basic and novel characteristics of the invention.

The support is used in a non-chrome acid plating process, preferably a plastic plating ("POP") process. The plating process is substantially free of chromic acid, in particular substantially free of chromic acid during the etching step of the plating process.

The contact surface of the support is the (outer) surface that is in contact with the etching and plating solution during a typical processing process. Typically, substantially the entire contact surface of the support comprises iodine-and/or bromine-treated plastic, more typically the entire contact surface of the support comprises iodine-and/or bromine-treated plastic.

The contact surface of the support comprises (consists essentially of or consists of) an iodine-treated and/or bromine-treated plastic. By "treating" is meant that the plastic is typically treated with iodine and/or bromine (i.e., I) ₂ And/or Br ₂ ) To contain iodine and/or bromine. Without being bound by theory, it is believed that iodine and/or bromine (i.e., I) ₂ And/or Br ₂ ) Due to this contact, impregnation into the surface of the plastic occurs. In other words, the iodine-and/or bromine-treated plastic may be an iodine-and/or bromine-impregnated plastic (i.e., molecular iodine/I), respectively ₂ Impregnation and/or molecular bromine/Br ₂ Impregnated plastic). The impregnation of iodine and/or bromine into the plastic can be observed by a colour change of the plastic, the iodine impregnated plastic being typically brown and the bromine impregnated plastic being typically orange. Because the use of iodine and/or bromine changes the color of the plastic, the present invention may enable a user to identify whether the plastic has been treated, as compared to the use of iodate solutions in conventional processes. Over time and/or with prolonged use, the effect of the iodine and/or bromine treatment may diminish, and the color of the plastic may change accordingly, allowing the operator to identify when further treatment of the support may be required.

The contact surface comprises iodine-treated and/or bromine-treated plastic. The contact surface preferably comprises an iodine treated plastic. While bromine is still effective, bromine is less persistent on the surface of plastics than iodine.

The plastic preferably comprises (consists essentially of or consists of) PVC, more preferably PVC plastisol. PVC or polyvinyl chloride is produced by polymerization of vinyl chloride monomer. PVC plastisols comprise a suspension of PVC particles in a liquid plasticizer. Iodine and/or bromine treatment of such materials may be particularly effective in inhibiting plating on such materials during electroless plating and/or electroplating.

The support preferably comprises metal at least partially coated with plastic. The presence of the metal may enable the plating current to be transmitted to the component supported by the support during the electroplating process. The metal preferably comprises copper and/or iron alloys. The metal may act as an electrode (cathode or anode) during the electroplating process. In particular, the support for holding the component is generally made of metal in order to transmit the current to the component during electroplating. The components are typically held in place on the support by spring contacts or clamps (hereinafter referred to as support clamps). In order to transmit the current, these support clamps necessarily have a small uncoated area so that electrical contact is maintained during machining of the component. The rest of the support is coated with an insulating plastic coating (usually PVC) in order to prevent the whole support from being plated. This coated surface is hereinafter referred to as the support contact surface. Typically, the portion of the support that is in contact with the power source to supply the electroplating current (typically on top of the support) is not coated because it is not immersed in the treatment solution.

The support preferably comprises a plating rack. The plating rack is particularly suitable for supporting one or more components during a plating process. Suitable shapes and configurations of stents are known in the art. The support may include, for example, one or more hooks or support clamps to support the part during the plating process. The support may include a cathode and/or an anode used in the electroplating process.

In another aspect, the invention comprises a plating apparatus for use in a chromium-acid free plating process, the plating apparatus comprising a plating vessel having one or more supports for supporting a part to be plated, the one or more supports having a contact surface comprising iodine-treated and/or bromine-treated plastic.

For the avoidance of doubt, the advantages and preferred features of the other aspects of the invention are equally applicable to this aspect.

The support may be a support as described herein.

The plating vessel is generally of a suitable shape and suitable dimensions to accommodate the parts to be plated during the plating process. Such plating vessels are known in the art. The interior surfaces (i.e., contact surfaces) of the container are typically substantially inert to the etching solutions and plating solutions used in the plating process.

In another aspect, the invention provides a method of treating a support for supporting a part to be plated in a chromium-free acid plating process, the support having a contact surface comprising a plastic, the method comprising:

providing a support for supporting a part to be plated in a chromium-free acid plating process, the support having a contact surface comprising a plastic;

providing an aqueous solution comprising one or both of iodine and bromine; and

at least a portion of the plastic of the contact surface of the support is contacted with an aqueous solution.

Similar to the first aspect, when the support is used during a non-chromate plating process, there may be substantially no deposition of copper or nickel on the support during a subsequent electroless deposition stage, and there may also be substantially no deposition on the support during a subsequent electroplating stage.

This treatment may result in the support described herein. The support may comprise, for example, a plating rack.

The plastic contact surface of the support may be in contact with the part to be plated during plating and may be in contact with the etching and/or plating solution used in the plating process.

The aqueous solution comprises iodine and bromine (i.e. molecular iodine (I) ₂ ) And molecular bromine (Br) ₂ ) Either or both).

Contacting at least a portion of the plastic of the contact surface of the support with the aqueous solution typically comprises at least partially immersing the support in the aqueous solution, more typically completely immersing the support in the aqueous solution.

The contacting may be carried out, for example, at a temperature between ambient temperature and 100 ℃. Since the ambient temperature is sufficient to perform, it is preferable to perform the method at ambient temperature in order to reduce costs and improve safety.

The aqueous solution preferably comprises iodine. While bromine is still effective, bromine is less persistent on the surface of plastics than iodine.

The aqueous solution preferably comprises, but is not limited to, 0.005M to 0.1M iodine, more preferably 0.01M to 0.05M iodine. The use of such an iodine concentration is particularly effective in inhibiting plating on the support during the plating process.

The aqueous solution preferably comprises iodide ions. Iodine (I) ₂ ) Are not particularly soluble in water. The presence of iodide ions may increase the solubility of iodine in aqueous solutions. For example, the presence of iodide ions may allow for the formation of aqueous solutions containing up to 12% iodine. The iodide may be introduced into the aqueous solution, for example, in the form of potassium iodide.

The molar ratio of iodide ion to iodine in the aqueous solution is preferably at least 1:1, more preferably at least 1.5:1, even more preferably at least 2: 1. Such ratios may enable the aqueous solution to advantageously contain large amounts of iodine.

Alternatively, other suitable means of increasing iodine solubility may be employed, such as introducing an effective amount of a co-solvent to render the desired concentration of iodine soluble. Suitable solvents are many and may include, but are not limited to, alcohols, glycols, and alkylene carbonates.

The step of providing an aqueous solution preferably comprises contacting iodide ions with iodate ions in an aqueous solution. From a commercial point of view, it is not desirable to dissolve iodine in, for example, a potassium iodide solution in order to provide both iodine and iodide ions in an aqueous solution. Advantageously, contacting the iodide ion with the iodate ion results in the in situ generation of iodine according to the following chemical reaction:

IO ₃ ^- +5I ^- +6H ⁺ →3H ₂ O+3I ₂

as an alternative to iodate ion, other oxidizing agents capable of oxidizing iodide ion to iodine can be used; for example, persulfate ions, nitrate ions, or hydrogen peroxide may be used. The present invention is not limited by the type of oxidant used to oxidize iodide ions to iodine. The iodide ion preferably generally exceeds the oxidant.

When the aqueous solution contains bromine, the corresponding bromate/bromide reaction can also be used to generate bromine in situ.

The support is preferably contacted with the aqueous solution for at least 10 seconds, more preferably for at least 30 seconds, even more preferably for 1 to 10 minutes, still even more preferably for 1 to 5 minutes. Such contact times can result in the support being particularly resistant to plating. Longer contact times may result in only a negligible improvement in plating resistance.

The plastic of the contact surface of the support preferably comprises (consists essentially of or consists of) PVC, more preferably PVC plastisol. Iodine and/or bromine treatment of such materials may be particularly effective in inhibiting plating on such materials during electroless plating and/or electroplating.

The plating process preferably comprises plating on an ABS polymer and/or an ABS/PC polymer. Such plating processes are particularly susceptible to causing plating on other plastic supports used in the process, such as plastic supports. ABS or "Acrylonitrile butadiene styrene" has the formula (C) ₈ H ₈ ) _x ·(C ₄ H ₆ ) _y ·(C ₃ H ₃ N) _z ) And are common thermoplastic polymers known in the art. ABS/PC includes blends of acrylonitrile butadiene styrene and polycarbonate.

In another aspect, the present invention provides a method of manufacturing a support as described herein, the method comprising the treatment method as described herein.

In another aspect, the invention provides a process for plating a part, the process comprising:

providing a part to be plated, the part having an outer surface comprising plastic;

providing a plating apparatus comprising a plating vessel having one or more supports for supporting a part to be plated, the one or more supports having a contact surface comprising iodine-treated and/or bromine-treated plastic;

mounting a component on a support of a plating apparatus to provide a mounted component;

contacting at least a portion of the plastic of the exterior surface of the installed component with an electrolyte to at least partially etch the plastic to form an etched surface of the component, the electrolyte being substantially free of chromic acid;

contacting at least a portion of the etched surface of the component with an activator solution to form an activated surface of the component; and

at least a portion of the activated surface of the component is contacted with an electroless nickel plating solution or an electroless copper plating solution to form a plated surface of the component.

The plating apparatus may comprise a plating apparatus as described herein. The support may comprise a support as described herein.

A "pre-etching" step may be performed before contacting at least a portion of the plastic of the outer surface of the mounted component with the electrolyte. This may involve, for example, contacting at least a portion of the plastic of the exterior surface of the installed part with an aqueous solvent blend containing propylene carbonate and butyrolactone. Such a pre-etching step is not always required, but may alter the plastic surface so that it is more easily etched.

Suitable chromate free electrolytes are known in the art. Contacting at least a portion of the plastic of the outer surface of the installed component with the electrolyte preferably comprises at least partially immersing the installed component in the electrolyte, more preferably completely immersing the installed component in the electrolyte. The contacting may be carried out at room temperature. However, the contacting is preferably carried out at elevated temperature, for example at a temperature above ambient temperature, more preferably above 30 ℃, even more preferably above 50 ℃, yet even more preferably above 60 ℃. Such high temperatures may help provide a suitable level of etching. To avoid loss of electrolyte, the contacting is preferably carried out at a temperature below 100 ℃, more preferably below 90 ℃, even more preferably below 80 ℃. The contacting is preferably carried out for at least 30 seconds, more preferably for at least one minute, even more preferably for at least 5 minutes, still even more preferably for from 1 minute to 30 minutes, still even more preferably for from 5 minutes to 20 minutes. Such contact times may provide suitable etch levels.

Suitable activator solutions are known in the art. Contacting at least a portion of the etched surface of the part with the activator solution preferably comprises at least partially immersing the etched part in the activator solution, more preferably completely immersing the etched part in the activator solution. While high temperatures can be used, the contacting is typically conducted at ambient temperature. The contacting is preferably carried out for at least 30 seconds, more preferably for at least one minute, even more preferably from 1 minute to 20 minutes, still even more preferably from 1 minute to 10 minutes.

The etched surface of the part may be contacted with an acid (e.g., hydrochloric acid) prior to contacting at least a portion of the etched surface with the activator solution. This is because typical activators include colloids which sometimes exhibit limited stability in water. If a wet plastic surface is immersed directly into a colloidal solution, the colloids at the plastic surface may become unstable.

Suitable electroless nickel and electroless copper plating solutions are known in the art. Typical chemical solutions include ions of nickel or copper along with a reducing agent (such as, for example, a hypophosphite reducing agent). Contacting at least a portion of the activated surface of the component with an electroless nickel plating solution or an electroless copper plating solution preferably comprises at least partially immersing the activated component in the electroless nickel plating solution or the electroless copper plating solution, more preferably completely immersing the activated component in the electroless nickel plating solution or the electroless copper plating solution.

After contact with the electrolyte and/or activator solution and/or electroless nickel plating solution and/or electroless copper plating solution and before the next step, the component is typically rinsed, more typically in water.

The components may generally comprise any plastic component that needs to be plated. Examples include automotive supports (e.g., automotive grills, headlamp enclosures, door handles, and trim pieces), shower accessory supports, bathroom accessory supports, home and furniture accessories, and electronic components (e.g., cameras, computers, telephones).

The iodine-and/or bromine-treated plastic preferably comprises (or consists essentially of, or consists of, in addition to iodine and/or bromine) PVC, and more preferably comprises PVC plastisol.

The plastic of the outer surface of the component preferably comprises (or consists essentially of or consists of) ABS and/or ABS/PC.

The etch electrolyte may be any suitable etch electrolyte that is substantially free of chromium (VI) and may include, for example, permanganate ions or other strong oxidants. Preferred electrolytes preferably contain manganese (III) ions in a solution of 9 to 15 moles of sulfuric or phosphoric acid. Such electrolytes are particularly effective in etching plastics without the use of chromic acid.

The activator solution preferably comprises a noble metal colloid. More preferably, the noble metal colloid comprises a first core metal and a second colloid metal colloidally surrounding the core; the core metal includes at least one metal selected from silver, platinum, palladium, and nickel, with palladium being particularly preferred; and the second colloidal metal comprises at least one metal selected from the group consisting of tin and lead, with tin being particularly preferred. The core metal can catalytically activate the deposition of electroless copper or electroless nickel. Such activator solutions are particularly effective in promoting the deposition of nickel or copper in subsequent electroless plating steps. An example of a commercially available suitable Activator is the Evolve Activator from MacDermid Enthone.

After contacting at least a portion of the etched surface of the component with the activator solution, at least a portion of the etched surface may be contacted with an accelerating solution. This can be used to remove colloidal metals from the core catalytic metal that might otherwise be shielded and might be ineffective. In other words, the activator post-treatment removes the second colloidal metal from the activated surface, thereby exposing the first core metal and performing a catalytic function. Suitable accelerating solutions are known in the art. The composition of the accelerating solution can vary widely and can be acidic or basic. Preferably, the accelerating solution is acidic and may, for example, contain chloride ions in combination with organic and inorganic acids. An example of a commercially available suitable Accelerator is the evolvent Accelerator from MacDermid Enthone.

Contacting at least a portion of the etched surface of the component with the accelerating solution preferably comprises at least partially immersing the etched and activated component in the accelerator solution, more preferably completely immersing the etched and activated component in the accelerator solution. The contacting is typically carried out at an elevated temperature (e.g., 50 c), although ambient or higher temperatures may be used. The contacting is preferably carried out for at least 30 seconds, more preferably for at least one minute, even more preferably from 1 minute to 20 minutes, still even more preferably from 1 minute to 10 minutes.

In a preferred embodiment, the process further comprises electroplating the plated surface of the part, wherein the support comprises a metal at least partially coated with an iodine-treated and/or bromine-treated plastic. As described above, the presence of the metal may enable the transfer of plating current to the component during the electroplating process. The plating preferably comprises copper plating.

In another aspect, the invention provides a component plated according to the process described herein.

In another aspect, the invention provides the use of an iodine and/or bromine pretreatment on a support for supporting a part to be plated to inhibit plating on the support during a chromium-free acid plating process, the support having a contact surface comprising a plastic.

The invention will now be described with reference to the following non-limiting drawings, in which:

fig. 1 shows a schematic view of an example of a support according to the invention.

Figure 2 shows a cross-section of a portion of the support of figure 1 along the line a-B.

Fig. 3 shows a schematic view of an example of a plating apparatus according to the present invention.

Fig. 4 shows a flow chart of an example of a method according to the invention.

Fig. 5 shows a flow chart of an example of a process according to the invention.

Referring to fig. 1-3, an example of a support (plating rack) 1 for use in a chromium-free acid plating process according to the invention is depicted. The support includes a plurality of hooks or support fixtures 2 to which the parts to be plated can be mounted during the plating process. The support has a contact surface comprising an iodine-and/or bromine-treated plastic 3. The interior of the support may comprise metal 4. At least a portion of the metal 4 of the support fixture 2 is not coated with iodine-treated and/or bromine-treated plastic 3, enabling the transmission of electrical current to the part during plating. Fig. 3 shows a plating apparatus 5 for use in a chromium-acid free plating process, the plating apparatus 5 comprising a plating vessel 6 having one or more supports 1 with a contact surface comprising an iodine-and/or bromine-treated plastic 3.

Referring to fig. 4, there is shown a method 7 of treating a support for supporting a part to be plated in a chromium-free acid plating process, the support having a contact surface comprising a plastic, the method comprising:

i. providing a support for supporting a part to be plated in a chromium-free acid plating process, the support having a contact surface comprising a plastic;

providing an aqueous solution comprising one or both of iodine and bromine; and

contacting at least a portion of the plastic of the contact surface of the support with an aqueous solution.

Referring to fig. 5, a process 8 for plating a part is shown, the process comprising:

a. providing a part to be plated, the part having an outer surface comprising plastic;

b. providing a plating apparatus comprising a plating vessel having one or more supports for supporting a part to be plated, the one or more supports having a contact surface comprising iodine-treated and/or bromine-treated plastic;

c. mounting a component on a support of a plating apparatus to provide a mounted component;

d. contacting at least a portion of the plastic of the exterior surface of the installed component with an electrolyte to at least partially etch the plastic to form an etched surface of the component, the electrolyte being substantially free of chromic acid;

e. contacting at least a portion of the etched surface of the component with an activator solution to form an activated surface of the component; and

f. at least a portion of the activated surface of the component is contacted with an electroless nickel plating solution or an electroless copper plating solution to form a plated surface of the component.

The process optionally further comprises:

g. plating a plated surface of the part, and wherein the support comprises a metal at least partially coated with an iodine-treated and/or bromine-treated plastic.

The invention will now be described in connection with the following non-limiting examples. All examples used the same PVC plastisol coating.

Example 1 (comparative example)

Plated stents with PVC plastisol coatings were treated in the following order (for simplicity, the rinse stage was omitted):

1. immersing in an aqueous solvent blend containing 100ml/l propylene carbonate and 50ml/l butyrolactone, and holding at 35 deg.C for 3 minutes

2. Based on the teaching of patent US10260000B2, etching was carried out in a chromium-free etchant (evove Etch from MacDermid Enthone) held at 68 ℃ for 10 minutes

3. Immersing in a 30% solution of 35 w/w% hydrochloric acid and holding at ambient temperature for 30 seconds

4. Immersed in a proprietary palladium colloid solution (evold Activator from MacDermid Enthone) and held at ambient temperature for 3 minutes.

5. Immersed in a proprietary accelerating solution (evolvent Accelerator 800 from MacDermid Enthone) and held at 50 ℃ for 2 minutes

6. Immersed in electroless nickel solution (Evave EN-60 from MacDermid Enthone) and held at ambient temperature for 7 minutes

After this treatment, the entire plated stent was covered with a coating of nickel.

Example 2 (comparative example)

1. immersing in a solution containing 10g/l of thiourea, and holding at 70 deg.C for 10 minutes

2. Immersing in an aqueous solvent blend containing 100ml/l propylene carbonate and 50ml/l butyrolactone, and holding at 35 deg.C for 3 minutes

3. Based on the teachings of patent US10260000B2, etched in a chromium-free etchant (evove Etch from MacDermid Enthone), held at 68 ℃ for 10 minutes 4 immersed in a 30% solution of 35 w/w% hydrochloric acid, held at ambient temperature for 30 seconds

5. Immersed in a proprietary palladium colloid solution (evold Activator from MacDermid Enthone) and held at ambient temperature for 3 minutes.

6. Immersed in a proprietary accelerating solution (evolvent Accelerator 800 from MacDermid Enthone) and held at 50 ℃ for 2 minutes

7. Immersed in electroless nickel solution (Evave EN-60 from MacDermid Enthone) and held at ambient temperature for 7 minutes

8. With 2Adm ^-2 Is plated in an acid copper electrolyte and maintained at ambient temperature for 40 minutes

It was observed that after stage 6, no nickel coating was observed on the stent, but after stage 7, a significant amount of copper plating was present on the PVC plastisol coating.

Example 3

1. immersing in a solution containing 0.05M iodine and holding at ambient temperature for 5 minutes

3. Based on the teaching of patent US10260000B2, etching in a chromium-free etchant (Evolve Etch from MacDermid Enthone) was carried out at 68 ℃ for 10 minutes

4. Immersed in a 30% solution of 35 w/w% hydrochloric acid and held at ambient temperature for 30 seconds

In this order, no nickel coating or copper plating was observed after the treatment. This sequence was repeated for another 4 cycles, but step 1 was omitted. No plating on the PVC plastisol was observed during these cycles. It was confirmed that iodine was not changed to form iodate ions in either the etching bath or the treatment step.

Example 4

1. immersing in a solution containing 0.01M iodine and holding at ambient temperature for 5 minutes

3. Based on the teaching of patent US10260000B2, etching was carried out in a chromium-free etchant (evove Etch from MacDermid Enthone) held at 68 ℃ for 10 minutes

4. Immersing in a 30% solution of 35 w/w% hydrochloric acid and holding at ambient temperature for 30 seconds

7. Immersed in electroless nickel plating solution (Evolve EN-60 from MacDermid Enthone) and held at ambient temperature for 7 minutes

In this order, no nickel coating or copper plating was observed after the treatment. This sequence was repeated for 2 more cycles, but step 1 was omitted. No plating on the PVC plastisol was observed during these cycles. It was confirmed that iodine was not changed to form iodate ions in either the etching bath or the treatment step.

Example 5 (comparative example)

Two coated stents with different PVC plastisol coatings were immersed in a solution of potassium iodate (30g/l) and held at 70 ℃ for 20 minutes. No color change was observed in any of the PVC plastisols plated the stent. This is consistent with the colorless nature of potassium iodate solutions.

The foregoing detailed description has been provided by way of illustration and description, and is not intended to limit the scope of the appended claims. Many variations of the preferred embodiments of the invention shown herein will be apparent to one of ordinary skill in the art and still be within the scope of the appended claims and their equivalents.

Claims

1. A support for supporting a part to be plated in a non-chromium acid plating process, the support having a contact surface comprising iodine-and/or bromine-treated plastic.

2. The support of claim 1, wherein the contact surface comprises iodine treated plastic.

3. A support according to claim 1 or claim 2, wherein the plastic comprises PVC, preferably PVC plastisol.

4. The support of any preceding claim, wherein the support comprises metal at least partially coated with the plastic.

5. A plating apparatus for use in a non-chromate plating process, the plating apparatus comprising a plating vessel having one or more supports for supporting a part to be plated, the one or more supports having a contact surface comprising iodine-treated and/or bromine-treated plastic.

6. A method of treating a support for supporting a part to be plated in a chromium-free acid plating process, the support having a contact surface comprising a plastic, the method comprising:

providing an aqueous solution comprising one or both of iodine and bromine; and

contacting at least a portion of the plastic of the contact surface of the support with the aqueous solution.

7. The method of claim 6, wherein the aqueous solution comprises iodine.

8. The method of claim 7, wherein the aqueous solution comprises 0.005M to 0.1M iodine, preferably 0.01M to 0.05M iodine.

9. The method of claim 7 or claim 8, wherein the aqueous solution comprises iodide ions.

10. The method of claim 8, wherein the molar ratio of iodide ion to iodine is at least 1: 1.

11. The method of any one of claims 7 to 10, wherein the step of providing the aqueous solution comprises contacting iodide ions with an oxidizing agent in the aqueous solution, the oxidizing agent selected from iodate ions, persulfate ions, nitrate ions, hydrogen peroxide, and combinations of two or more thereof, preferably wherein the oxidizing agent comprises iodate ions.

12. The method according to any one of claims 6 to 11, wherein the support is contacted with the aqueous solution for at least 10 seconds, preferably for at least 30 seconds, more preferably for 1 to 10 minutes, even more preferably for 1 to 5 minutes.

13. The method according to any one of claims 6 to 12, wherein the plastic of the contact surface of the support comprises PVC, preferably PVC plastisol.

14. The method of any one of claims 6 to 13, wherein the plating process comprises plating on an ABS polymer and/or an ABS/PC polymer.

15. A method of manufacturing a support according to any of claims 1 to 4, the method comprising a method according to any of claims 6 to 14.

16. A process for plating a part, the process comprising:

mounting the component on a support of the plating apparatus to provide a mounted component;

contacting at least a portion of the activated surface of the component with an electroless nickel plating solution or an electroless copper plating solution to form a plated surface of the component.

17. The process of claim 16, wherein:

the iodine-and/or bromine-treated plastic comprises PVC, preferably PVC plastisol; and/or

The plastic of the outer surface of the component comprises ABS and/or ABS/PC.

18. The process of claim 16 or claim 17, wherein:

the electrolyte comprises manganese (III) ions in a solution of 9 to 15 moles of sulfuric or phosphoric acid; and/or

The activator solution comprises a noble metal colloid, preferably wherein the noble metal colloid comprises a first core metal and a colloidal metal colloidally surrounding the core; the core metal includes at least one metal selected from silver, platinum, palladium, and nickel; and the colloidal metal includes at least one metal selected from tin and lead.

19. The process of any one of claims 16 to 18, wherein the process further comprises electroplating the plated surface of the part, and wherein the support comprises a metal at least partially coated with the iodine-and/or bromine-treated plastic.

20. Use of an iodine and/or bromine pretreatment on a support for supporting a part to be plated to inhibit plating on the support during a chromium acid free plating process, the support having a contact surface comprising a plastic.