TWI632205B - Additive for lds plastics - Google Patents

Abstract

The present invention relates to an LDS active additive for LDS plastics, to a polymer composition comprising an additive of this type, and to an article having a metallized conductor track, wherein the polymeric matrix of the article or on the substrate The polymeric coating comprises an LDS additive of this type.

Description

Additive for use in LDS (laser direct molding) plastics

The present invention relates to an LDS active additive for LDS plastics; in particular, to the use of a composite pigment consisting essentially of titanium dioxide and antimony-doped tin dioxide as an LDS additive in a polymer composition for an LDS process; a polymer composition comprising an additive of this type; and an article having a metallized conductor track, wherein the polymerizable matrix of the article or the polymeric coating on the basic body comprises This type of LDS additive.

Three-dimensional plastic components with circuits, so-called MIDs (Molded Interconnects), have been on the market for many years and are a key contributor to the promotion of the latest technologies related to many applications, such as telecommunications, automotive construction or medical technology. As such, they also contribute significantly to the miniaturization and complication of individual electronic components of these applications.

There are many ways to make a three-dimensional MID to get a basic component containing plastic or a basic component with a coating containing plastic, for example, by 2 The component injection molding or hot stamping provides the required circuit structure. Typically, this requires a special product-specific mold that is expensive to purchase and has low flexibility in use.

On the contrary, LPKF's LDS process (laser direct molding process) provides a key advantage in that the circuit structure can be directly connected to the plastic substrate part or the plastic part on the base part by means of a laser beam. The coating can be metallized later.

A simpler process, such as, for example, a 1-component injection molding process, is suitable for making plastic substrate portions, and can also control the cutting-in of the circuit structure in three dimensions.

In order to be able to obtain a circuit structure that can be metallized by means of a laser beam, so-called LDS additives must be added to the plastic substrate part or to the plastic-containing coating. This additive must react with the laser radiation and at the same time prepare for subsequent metallization. The LDS additive typically comprises a metal compound that is activated during the processing of the laser beam in the laser treatment zone by releasing the metal core, which facilitates subsequent deposition of the conductive metal for activation in the plastic. The dots form a circuit. At the same time, these metal compounds react in a laser-activated manner (usually absorbing lasers) and ensure that the laser-treated areas of the plastic are ablated and carbonized, causing the circuit structure to be engraved into the plastic substrate portion. At the point where the plastic is not laser activated, the metal compound remains unchanged. The LDS additive may be added to the plastic material as a whole prior to molding to provide a plastic substrate portion, or may be present only in the surface of the circuit structure that will be cut by the laser beam as a separate plastic containing layer, coating, coating layer, and the like. Composition.

When processed with a laser beam, in addition to the future circuit structure containing a metal core, a micro-rough surface is also formed in the circuit structure, which provides a conductive metal (usually copper) that can itself be strong during subsequent metallization processes. The necessary conditions for fixing the adhesive to the plastic.

This metallization treatment is usually carried out later in a currentless copper bath, after which a further application of nickel and gold layers can be carried out, which is also carried out in a currentless bath. However, other metals such as tin, silver and palladium may also be applied, optionally in combination with, for example, gold. The plastic components pre-formed in this way are then mated with individual electronic components.

The purpose of the LDS process is to fabricate a three-dimensional conductive circuit structure on a three-dimensional plastic substrate or a substrate having a plastic-containing coating. Of course, for this purpose, only the metallized circuit structure produced can be electrically conductive, rather than the plastic substrate or the coating itself. Therefore, the previously proposed LDS additive is generally an additive that is not electrically conductive and does not impart conductivity to the substrate material.

Initially, attempts were made to use non-conductive organic heavy metal complexes, especially those containing palladium (EP 0 917 597 B1) as LDS additives.

In EP 1 274 288 B1, inorganic metal compounds and non-metals which are insoluble in the application medium and which are metals of group d or f of the periodic table are added as LDS additives for plastics. Copper compounds, in particular copper spinels, are preferably used.

However, the disadvantages of organic Pd complexes and copper spinels are that they are inherently deep in color and also make the plastic containing them appear deep. color. In addition, the copper compound partially decomposes the plastic molecules surrounding it. However, especially for MIDs intended for telecommunications, there is an increasing demand for plastics with a light inherent color because the color can be colored in all desired colors without the need to add a high weight ratio of colored pigments to the LDS additive. Performance has a negative impact or reduction. In addition, the decomposition of the plastic substrate is undesired.

In order to adapt a light-colored plastic to an LDS process, EP 2 476 723 A1 therefore proposes a tectoalumosilicate (zeolite) as an LDS additive for plastics.

WO 2012/126831 proposes plastics suitable for LDS and corresponding LDS processes in which an LDS additive comprising cerium-doped tin dioxide and having an L* value (luminance) of at least 45 in the CIELab color space is added. The mica coated with antimony doped tin dioxide is preferably applied in an amount of from 2 to 25% by weight, based on the total mass of the plastic material. In addition, a white pigment is added to give the plastic material a lighter color.

WO 2012/056416 also proposes a composition comprising from 0.5 to 25% by weight of a metal oxide coated filler, wherein the latter is preferably mica coated with antimony doped tin dioxide. The LDS plastic material has an L* value of 40 to 85. Colored pigments can also be added to this plastic material.

Mica flakes coated with antimony doped tin dioxide are generally used as conductive pigments in a very wide range of applications, wherein, for example, plastic materials are imparted with antistatic properties. The pigment of the composition also acts as an additive for laser-engraved plastics because the mica coated with antimony-doped tin dioxide absorbs general laser radiation and the stored heat penetrates into the surrounding pigment. The plastic matrix turns it black. If the critical use concentration is exceeded, the use of mica doped with antimony doped tin dioxide as the LDS additive in the corresponding plastic material suitable for LDS can therefore also promote the formation of a conductive path there. However, conductive plastics are less suitable for LDS processes because they significantly impair the electrical conductivity of the circuit structure applied to the plastic substrate portion and the resulting MID is not suitable for the stringent dielectric properties of the plastic substrate portion. Specific high frequency applications (HF applications) such as mobile phones with integrated antennas or electronic components for WLAN systems.

In order to obtain plastics having a good dielectric value for polymer materials suitable for the LDS process, and by Peter to electronic components suitable for HF, for example, in US 8,309,640 B2 it is proposed to add ceramics in addition to the appropriate LDS additives. A filler having a dielectric constant of at least 25 for a thermoplastic material as measured at 900 MHz. However, since the LDS additive used herein is a general copper compound which has been mentioned before, although a plastic suitable for this type of LDS has a good dielectric value, it is dark to black.

Therefore, there is still a need for plastics that are suitable for LDS processes and have a shallow inherent color and have a high dielectric value in the polymer material, making them useful for high frequency applications. In particular, there is a need for suitable LDS additives for plastics. When it is necessary to meet all other requirements of the LDS additive, that is, the ability to activate by laser radiation, the metal core is released by laser bombardment and the micro-rough surface is formed by the laser beam as the basis for subsequent metallization.

Accordingly, it is an object of the present invention to provide an LDS additive for LDS plastics which, by virtue of its shallow intrinsic color, is capable of producing a light colored LDS plastic which can be conveniently colored using a small amount of colored colorant dopants. This imparts a dielectric property to the plastic or only a slight electrical conductivity, making this plastic suitable for high frequency applications, and where possible, avoiding the decomposition of the surrounding plastic matrix with the use of laser parameters of the greatest possible bandwidth, and Good metallization of the circuit structure available in the LDS process.

Another object of the present invention is to provide a polymerizable composition which is suitable for the LDS process and has the aforementioned properties.

Another object of the present invention is to provide an article having a circuit structure fabricated by an LDS process and having the aforementioned properties.

The object of the invention is achieved by using a composite pigment comprising at least 80% by weight of titanium dioxide (TiO ₂ ) and cerium-doped tin dioxide ((Sb, Sn)O ₂ ) based on the total weight of the composite pigment. The composition is used as an LDS additive (laser direct molding additive) in the polymerizable composition.

Further, the object of the present invention is achieved by a polymerizable composition comprising at least one organic polymerizable plastic and an LDS additive, wherein the LDS additive is a composite pigment having at least 80% by weight of titanium dioxide based on the total weight of the composite pigment ( TiO ₂ ) and cerium-doped tin dioxide ((Sb,Sn)O ₂ ).

Furthermore, the object of the invention is achieved by an article having a circuit structure manufactured by an LDS process, the article being a polymerized substrate of the article or a substrate having the polymer-containing coating and a metal conductor on the surface of the substrate The composition of the rail, wherein the polymer-containing coating of the polymerizable matrix or matrix comprises an LDS additive consisting of a composite pigment comprising at least 80% by weight of titanium dioxide based on the total weight of the composite pigment ( TiO ₂ ) and cerium-doped tin dioxide ((Sb,Sn)O ₂ ).

Composite pigments consisting essentially of titanium dioxide (TiO ₂ ) and antimony-doped tin dioxide ((Sb, Sn)O ₂ ), in particular by titanium dioxide core and doped germanium present on the core, are known. A composite pigment consisting of a tin coating. These pigments may also optionally have a protective layer and/or an interlayer between the core and the (Sb, Sn)O ₂ coating. Pigments of this type, in which the TiO ₂ cores can have various geometries, have long been used as antistatic agents in coatings and plastics. They are themselves electrically conductive and also impart conductivity to a coating or plastic containing a sufficient concentration. In order to increase this conductivity, in particular, in recent years, a pigment having a TiO ₂ core which is needle-like has been developed.

Surprisingly, however, it has now been found that a composite pigment consisting of at least 80% by weight of TiO ₂ and cerium-doped tin dioxide based on the total weight of the composite pigment is highly suitable as an LDS additive for the polymerizable composition.

Accordingly, the present invention is directed to the use of the composite pigment as an LDS additive in a polymeric composition for use in an LDS process.

Figure 1 shows a SEM photograph of an LDS additive according to the present invention according to Example 1.

The composite pigments used in accordance with the invention have at least one core and a coating on the core. The coating can be composed of one or more individual layers.

In the simplest case, the coating consists of a single, functional layer. Furthermore, the coating may have one or more interlayers between the core and the functional layer and/or may also have one or more protective layers on the surface of the functional layer.

If a single composite pigment particle consists entirely of a single core and a coating on the core, the composite pigment used in accordance with the invention consists entirely of primary particles and is therefore monodisperse. However, in a more common and thus preferred embodiment, the composite pigment used is an agglomerate of two or more primary particles, where each primary particle has a core and is located in the core. Coating on.

According to the invention, the primary particles are layer structures having a sequence of core/functional layers, layer structures of core/interlayer/functional layers, layer structures of core/functional layers/protective layers or core/interlayer/functional layers/protective layers A layered composite pigment can be used. According to the invention, the core or the functional layer consists of TiO ₂ or cerium-doped tin dioxide.

Since the core and functional layers in one and the same composite pigment or primary particles are naturally not composed of the same material, the composite pigment used in accordance with the present invention may have the following composition: TiO ₂ core / (Sb, Sn) O ₂ layer , TiO ₂ core/interlayer/(Sb,Sn)O ₂ layer, TiO ₂ core/(Sb,Sn)O ₂ layer/protective layer, TiO ₂ core/interlayer/(Sb,Sn)O ₂ layer/protective layer, (Sb,Sn)O ₂ core/TiO ₂ layer, (Sb,Sn)O ₂ core/interlayer/TiO ₂ layer, (Sb,Sn)O ₂ core/TiO ₂ layer/protective layer, (Sb,Sn)O ₂ core / interlayer / TiO ₂ layer / protective layer.

The weight ratio of the sum of the core and the functional layer (i.e., the sum of the TiO ₂ and the antimony-doped tin dioxide) is at least 80% by weight, in each case, based on the total weight of the composite pigment, preferably It is at least 90% by weight, and in particular 95-100% by weight. This means that in a particularly preferred embodiment of the invention, the composite pigment used consists entirely of TiO ₂ and (Sb,Sn)O ₂ , or optionally only a very small amount of other constituents.

An antimony-doped tin dioxide system, whether as a core or as a functional layer in the primary particle coating, the weight percentage of rhenium relative to tin is between 2 and 35% by weight, preferably from 8 to 30% by weight. And in particular from 10 to 20% by weight of the material (this is based on the total weight of bismuth and tin).

If interlayers and/or protective layers are present, these are primarily composed of inorganic materials in the case of interlayers. A highly suitable interlayer is a metal oxide, in particular SiO ₂ , SnO ₂ , Al ₂ O ₃ , ZnO, CaO, ZrO ₂ , Sb ₂ O ₃ , or a mixture thereof.

Conversely, a protective layer, which may be present on the surface of the composite pigment used, may have an inorganic or organic nature. If the use of the composite pigments in the application medium (i.e., organic polymeric plastics herein) is simplified or even possible to apply entirely by the associated surface coating, it is usually applied. However, it is also possible to apply it to any desired color. In the case of the inorganic protective layer, preferably ZrO ₂ , Ce ₂ O ₃ , Cr ₂ O ₃ , CaO, SiO ₂ , Al ₂ O ₃ , ZnO, TiO ₂ , SnO ₂ , strontium-doped SnO ₂ , Sb ₂ O ₃ , or a corresponding oxide hydrate, or a mixture of two or more thereof.

The organic protective layer usually consists of a suitable organic decane, an organic titanate or an organic zirconate. Suitable materials are known to those skilled in the art as reagents for surface coating and post-coating of effect pigments.

The total weight ratio of the interlayer and/or protective layer here is up to 20% by weight, preferably up to 10% by weight, and particularly preferably from 0 to 5% by weight, based on the total weight of the composite pigment.

In a preferred embodiment of the invention, the composite pigment as an LDS additive consists entirely of one or more primary particles, which in each case consist of a core and a functional coating on the core (ie, From the TiO ₂ core and (Sb,Sn)O ₂ coating or from the (Sb,Sn)O ₂ core and TiO ₂ coating); but in the most preferred embodiment, the composite pigment is composed of primary particles In composition, the primary particles are in each case composed of a TiO ₂ core and a (Sb, Sn)O ₂ coating. Optionally, up to 5% by weight of the foreign component is present, based on the total weight of the composite pigment, which may be present in the interlayer and/or protective layer.

The core in the composite pigment used in accordance with the invention may itself have any possible shape. However, especially with regard to the use of a composite pigment as an LDS additive for use in the present invention to impart conductivity to a polymerizable plastic, it has proven to be advantageous for the core in the composite pigment to have an isotropic shape. These are Ideally, the imaginary center point view has almost the same shape in all directions of the core (ie, there is no preferential direction. These include spherical and cubic nuclei, and nuclei with irregular, tightly shaped, However, it may also be a shape of a regular polyhedra or a semi-regular polyhedra (Platonic bodies and Archimedean bodies) having n faces, wherein n is 4 to Within the scope of 92. Needless to say, the so-called spherical, cubic or regular polyhedron is also used for the nuclear shape of a non-ideal spherical, ideal cubic or ideal regular polyhedron from a geometrical point of view. Manufactured, so technically caused deviations from the ideal geometry (for example, in the case of polyhedrons, rounded edges or surfaces of slightly different size and shape) are also included.

The core in the composite pigment used in accordance with the invention has a particle size in the range of from 0.001 to 10 microns, preferably from 0.001 to 5 microns and especially from 0.01 to 3 microns. It consists of TiO ₂ or (Sb,Sn)O ₂ which can be purchased from the market in the size shown. Thus, for example, the TiO ₂ particles may be commercially available under the trade names KRONOS (KRONOS Worldwide, Inc.), HOMBITEC (Sachtleben) or Tipaque (Ishihara Corp.). The antimony-doped tin dioxide particles may be, for example, a commercial product under the name Zelec (Milliken Chemical) or SN (Ishihara Corp.).

On the surface of the core having the above-mentioned size and material composition, the primary particles of the composite pigment used in accordance with the present invention may have a layer thickness in the range of 1 to 500 nm, preferably in the range of 1 to 200 nm. Paint Floor.

The coating comprises, as mentioned above, at least one functional layer which, depending on the material composition of the core, consists of TiO ₂ or (Sb, Sn)O ₂ . The interlayer or protective layer, if present, is also considered a coating. The aforementioned size class for the layer thickness of the coating can be used for both the coating consisting entirely of the aforementioned functional layer and the coating having one or more interlayers and/or protective layers in addition to the functional layer. Particularly preferably, the layer thickness of the coating consisting entirely of the (Sb, Sn)O ₂ functional layer ranges from 1 to 100 nm.

The proportion of the coating is from 20 to 70% by weight, based on the total weight of the primary particles, and is also from 20 to 70% by weight, based on the total weight of the composite pigment. These data relate to both a coating consisting entirely of the aforementioned functional layers and a coating having one or more interlayers and/or protective layers in addition to the functional layers.

If the core consists of TiO ₂ , the proportion of the functional layer comprising at least one (Sb,Sn)O ₂ or the functional layer composed of at least one functional layer of (Sb,SnO ₂ ) is particularly preferably at 35 Within the range of 55 wt%, especially in the range of 40 to 50 wt% (based on the total weight of the primary particles or the total weight of the composite pigment).

If the core consists of (Sb,Sn)O ₂ , the proportion of the functional layer comprising at least one TiO ₂ or the functional layer composed of at least one functional layer of TiO ₂ is particularly preferably in the range from 45 to 65% by weight. Within, in particular in the range from 50 to 60% by weight (this total weight of the primary particles or the total weight of the composite pigment).

The composite pigments used in accordance with the invention have a particle size ranging from 0.1 to 20 microns, preferably from 0.1 to 10 microns and especially from 0.1 to 5 microns. Particularly preferred, the use of a particle size range of 0.1 to 1 micrometer and a D ₉₀ value range of the composite pigment is from 0.70 to 0.90 microns.

All particle sizes shown above can be determined by conventional methods for particle size determination. A particularly preferred method for particle size determination is a laser diffraction method which advantageously determines the nominal particle size of individual particles and their particle size distribution percentage. All particle size measurements performed in the present invention were determined by a laser diffraction method using a Malvern 2000 instrument (Malvern Instruments Ltd., UK) under standard conditions of ISO/DIS 13320.

The layer thickness of each coating is determined numerically from the SEM and/or TEM images.

The composite pigments used in accordance with the invention are produced by processes known per se. Among them, the starting particles as a core are provided as a coating layer comprising at least one functional layer (one of the compositions shown above), but preferably consists entirely of this functional layer. Since the starting materials in each case are inorganic, the coating of the core with the functional layer is preferably carried out in the aqueous suspension by precipitation of individual metal oxides or metal oxide hydrates and subsequent conversion to metal compounds. . The precursor material of the metal oxide to be obtained, usually a metal salt, is added in dissolved form to an aqueous suspension of the individual core material and allowed to precipitate on the core at a suitably set pH, usually hydrated with a metal oxide. Precipitation in the form of matter. The metal oxide hydrate is later converted to the corresponding oxide by treatment with increased temperature. The coating of the core having any of the applied interlayers and/or protective layers can be carried out in the same manner as in the case of the inorganic layer. Organic post-coating can also be carried out by the methods conventional in the prior art, in particular By contacting the surface of the composite particles with the corresponding organic material in a suitable medium.

The composite pigments used in accordance with the invention are produced in the following manner, with reference to an example of a TiO ₂ core having a functional coating of antimony-doped tin dioxide:

The substantially spherical TiO ₂ particles of the desired size are mixed with demineralized water to obtain a suspension which is heated to a temperature in the range of 70 to 90 ° C under stirring. The pH of the suspension is adjusted to a value in the range of 1.5 to 2.5 using an acid (for example, hydrochloric acid). The tin ruthenium chloride solution to be composed in a hydrochloric acid solution is added to the suspension while maintaining the pH constant with a base (for example, a sodium hydroxide solution). After the addition is complete, the pH is increased to a value >2 to 7.0 and stirring is continued. The product is filtered off, washed, dried and calcined at a temperature ranging from 500 ° C to 900 ° C for 0.5 to 2 hours. This product was then sifted arbitrarily. A composite pigment comprising a TiO ₂ core having a (Sb, Sn)O ₂ coating was obtained.

The (Sb,Sn) O ₂ core particles are coated with TiO ₂ and can be carried out in a similar process in an aqueous suspension at a pH ranging from 1.5 to 2.5 using a suitable titanium salt (for example using TiCl ₄ ).

The composite pigment is present in the individual polymerizable composition in an amount of from 0.1 to 30% by weight, preferably from 0.5 to 15% by weight, particularly from 1 to 10% by weight, based on the total weight of the polymerizable composition. Used as an LDS additive. It can also be used in polymerizable compositions suitable for LDS together with other LDS additives known in the prior art. In the latter case, the proportion of the LDS additive according to the present invention is due to other LDS additives. The proportion is reduced. The total amount of LDS additive is generally not more than 30% by weight as indicated above, based on the total weight of the polymerizable composition suitable for LDS.

The polymerizable composition is preferably a thermoplastic polymerizable composition, and a major portion (usually > 50% by weight) is composed of a thermoplastic.

Suitable thermoplastics are amorphous and semi-crystalline thermoplastics with diverse material choices such as various polyamines (PA), polycarbonates (PC), polyamines (PPA), and polyphenylene ethers. (PPO), polybutylene terephthalate (PBT), cycloolefin polymer (COP), liquid crystal polymer (LCP) or copolymers or blends thereof, for example, acrylonitrile-butadiene-benzene Ethylene/polycarbonate blend (PC/ABS) or PBT/PET. Self-learning polymer manufacturers can achieve quality for those who apply to LDS.

Further, the polymerizable composition comprising the composite pigment used in accordance with the present invention as an LDS additive may optionally further comprise a filler and/or a colorant and a stabilizer, an adjuvant and/or a flame retardant.

Suitable fillers are, for example, various phthalates, SiO ₂ , talc, kaolin, mica, ash, glass fibers, glass beads, carbon fibers and the like.

Suitable colorants are both organic dyes and inorganic or organic coloring pigments. Since the LDS plastic composition containing the LDS additive according to the present invention is very light colored and thus easy to color, substantially all soluble dyes or non-soluble colored pigments suitable for plastics can be used. The examples which may be mentioned here are only the particularly commonly used white pigments TiO ₂ , ZnO, BaSO ₄ and CaCO ₃ . Here, the amount and type of filler and/or colorant added is limited only by the nature of the individual specific materials (especially the plastics used) that are suitable for the individual compositions of the LDS.

Surprisingly, it has been found that a composite pigment according to the invention consists of at least 80% by weight of TiO ₂ and (Sb,Sn)O ₂ based on the total weight of the composite pigment, which is very suitable as an LDS additive and Even in the polymerizable composition for the LDS process which is added at a usual concentration of 0.1 to 30% by weight, it does not form in the polymerizable matrix of the article to be manufactured or the polymer-containing coating on the substrate. Conductive path, although the composite pigment has some conductivity. In addition, they have a light, white-grey to blue-grey inherent color that does not provide a disturbing deep natural color on the plastic to which it is added. Plastics containing only the additive according to the invention at a concentration of 2% by weight of plastic have an L* value (luminance value) determined in the CIELab* system of greater than 65 (determined using Minolta CR-300). Therefore, if necessary, all of the color pigments can be used to color the plastics suitable for the LDS containing the LDS additive according to the present invention, and there is no possibility that a large amount of the colorant is lowered or the performance of the LDS additive is impaired. At the same time, however, the LDS additive used in accordance with the present invention has high laser activity and, when subjected to a laser in the LDS process, obtains a desired micro-rough surface in a conductive structure that is ablated and carbonized by a laser beam, such that subsequent The metallization has good quality. Under the best conditions, excellent metallization is achieved as much as possible, and it is particularly surprising that excellent metallization is achieved with various laser settings of large bandwidth. Therefore, for the LDS process, the conditions that best suit the laser action of the actual environment can be selected in each case without degrading the expected quality of subsequent metallization. If the LDS additive used is a particularly preferred embodiment of the invention, i.e., a composite pigment having a TiO ₂ core and a ruthenium-doped tin dioxide on the surface of the core or at least predominantly a coating thereof, When the LDS additive is used in a plastic-containing polymerizable composition, decomposition of the organic polymer molecules surrounding the composite pigment does not occur.

However, it is particularly surprising that, as mentioned before, a composition suitable for LDS comprising an LDS additive used according to the invention and having no other conductive components is satisfactory for use in the high frequency range (HF range, 1-20 GHz) conditions of. To achieve this, the plastic composition must have a relatively low relative permittivity ε _{, r} (the ratio of the permittivity of the medium to the vacuum) and a low dielectric loss factor tan δ (measuring the energy loss caused by the medium in the electric field) . Both of these parameters are related to both frequency and temperature and should therefore be determined under the conditions of use in which the electronic components to be manufactured by the LDS process are normally operable. For high frequency applications, suitable measurement conditions are therefore room temperature and frequencies of at least 1 GHz. If these polymerizable compositions are suitable for HF applications, the dielectric loss factor of the composition suitable for LDS containing the LDS additive should not be higher than 0.01 when measured at a frequency equal to or higher than 1 GHz. A polymerizable composition, particularly a thermoplastic composition, comprising the aforementioned amount of the LDS additive used in accordance with the present invention and having no other conductive component satisfies the conditions.

The present invention also relates to a polymerizable composition comprising at least one organic polymerizable plastic and an LDS additive, wherein the LDS additive is a composite pigment comprising at least 80% by weight of titanium dioxide (TiO ₂ ) based on the total weight of the composite pigment. And doped antimony-doped tin dioxide ((Sb, Sn)O ₂ ). The polymerizable composition herein contains an LDS additive in a proportion of 0.1 to 30% by weight based on the total weight of the polymerizable composition.

Details regarding the material composition of the LDS additive, the polymer material used, and any adjuvants and additives present (e.g., fillers, colorants, etc.) are described above. Please refer to the aforementioned.

It is attempted to use the polymerizable composition according to the present invention for an LDS process (laser direct molding) for fabricating a metallized circuit structure on a three-dimensional plastic substrate or a three-dimensional substrate with a plastic-containing coating. It (when no colorant is used) has a light intrinsic color and can be colored with a conventional dye and/or a coloring pigment if necessary, which is extremely suitable for high frequency applications and can be added by adding an LDS additive according to the present invention. It is effective to make the conductive structure made by the laser beam have good metallisability, and the laser parameters can be selected in a wide spectrum.

The invention also relates to an article having a circuit structure fabricated by an LDS process, wherein the article consists of a polymer matrix or a substrate having a polymer-containing coating and a metal conductor track on the surface of the substrate, wherein the polymerizable matrix Or the polymer-containing coating of the matrix comprises an LDS additive consisting of a composite pigment consisting of at least 80% by weight of titanium dioxide (TiO ₂ ) and cerium-doped dioxide, based on the total weight of the composite pigment. Tin ((Sb,Sn)O ₂ ) is composed). The article, in particular an article comprising an organic plastic, is used, for example, in telecommunications, medical technology or in the construction of automobiles, wherein it is used as an electronic component, for example, as a mobile phone, a hearing aid, a dental instrument, an automatic electronic device or the like. .

The invention will be explained below with reference to examples, but the invention is not limited thereto.

Example 1:

Manufacturing of composite pigments:

100 g has an average particle size in the range of 100-300 nm (by laser diffraction, using a measuring instrument from Malvern Ltd., UK., measured by standard conditions) of substantially spherical TiO ₂ particles (Kronos 2900, product of KRONOS Inc.) were heated to 75 ° C in 2 liters of demineralized water and stirred. The pH of the suspension was adjusted to 2.0 using 10% hydrochloric acid. Thereafter, a solution of tin chloride in hydrochloric acid (composed of 264.5 g of 50% SnCl ₄ solution, 60.4 g of 35% SbCl ₃ solution and 440 g of 10% hydrochloric acid solution) is slowly added, here, by slowly adding simultaneously A 32% sodium hydroxide solution maintains the pH of the suspension constant. After the addition was complete, the mixture was stirred for a further 15 minutes. Thereafter, the pH was adjusted to 3.0 by adding a 32% sodium hydroxide solution, and the mixture was further stirred for 30 minutes.

The product was filtered, washed, dried, calcined at 500-900 ° C for 30 minutes and sieved through a 50 micron sieve.

A composite pigment comprising TiO ₂ and (Sb,Sn)O ₂ having a particle size in the range of 0.1 to 1.7 μm, a D ₅₀ value of 0.18 μm, and a D ₉₀ value of 0.74 μm was obtained. This composite pigment has a light green-grey primary hue. The Sn:Sb ratio in the coating is 85:15.

Use case 1:

In the CIELab* system, the luminance value corresponding to L* was measured and determined using a Minolta CR-300 measuring instrument available from Minolta Co., Ltd.:

The 5% by weight LDS additive was incorporated into PC/ABS (Xantar C CM 406, Mitsubishi Engineering Plastics) by a co-rotating twin-screw extruder. This extrudate was granulated by long strips and then dried at 100 °C. Thereafter, a test plate having a size of 60 x 90 x 1.5 mm was injection molded in an injection molding machine.

The luminance value L* was measured in a CIELab system under standard conditions using a Minolta CR-300 measuring instrument. Each lists the average of 5 different assays.

The following values were measured:

As can be seen from Table 1, the composite pigment used in accordance with the present invention has a significantly higher luminance value in the polymerizable plastic matrix than particles composed of antimony doped tin dioxide. When the concentration of the LDS additive is half or the same, the luminance value according to the example of the present invention is slightly better than the comparative example as compared with the antimony doped tin dioxide coated mica.

Use case 2:

Detection of metallization properties:

Similar to the use of Example 1, in each case, 5% by weight of LDS additive (Cu spinel, according to the material of Comparative Example 4 and the material according to Example 1 of the present invention) was incorporated into PC/ABS by an extruder, in an injection mold. In the machine, a test plate was prepared from the obtained compound. This test panel uses different laser intensities and frequencies in the range of 3-16 watts and 60-100 kHz in a test field in a grid via a 1064 nm fiber laser. The treated area is carbonized while the material is slightly ablated). Thereafter, metallization treatment was carried out with copper in a commercially available reactive copper bath (MID Copper 100 B1, MacDermid). The metallization properties were evaluated against the copper layer structure on the substrate. A plating index (according to MacDermid) was obtained which was obtained from the quotient of the cumulative copper layer of the built-up copper layer of the test material and the control material. The control material used was a PBT test plate with a copper spinel ratio of 5% by weight.

In terms of metallization within the range of laser parameters and in the nominal value of the plating index, experiments have shown that the LDS additive used in accordance with the present invention exhibits significantly better values than the doped cerium dioxide according to Comparative Example 4. Tin-coated mica flakes, the former having a peak similar to Cu spinel and exhibiting excellent metallization values, especially at relatively high laser powers.

Use case 3:

Material determination for HF suitability:

The measurement object was as the test plate from Use Example 2, except that it was not subjected to laser treatment and metallization before the test.

The permittivity of the material is determined in various frequency ranges and using various methods. This measurement was carried out at room temperature. For the measurement in the frequency range of 1 MHz to 1 GHz, an Agilent E4991A impedance analyzer and an Agilent 16453 test stand were used. Evaluation was performed using the E4991A's "Material Measurement Firmware".

For the measurements at 2.69 GHz and 3.9 GHz, a high quality resonator (resonator resonator, TE111 type) was used, and the resonance of the empty resonator and the resonator containing the dielectric sample was measured using a Rhode & Schwarz ZVA network analyzer. This evaluation is based on the calculation procedure in S. Zinal and G. Boeck, "Complex Permittivity Measurements using TE11p Modes in Circular Cylindrical Cavities," IEEE Trans, Microwave Theory Tech. , Vol . 53, pp . 1870-1874, June 2005. .

The following measured values were obtained at 1 GHz:

The following measured values were obtained at a frequency of 2.69 GHz:

The following measured values were obtained at a frequency of 3.9 GHz:

As indicated by the measurement, the suitability of copper spinel as an LDS additive and the LDS additive according to Example 1 used in accordance with the present invention in the high frequency range is generally similar, while the antimony doped tin dioxide coated mica is used. The relative permittivity of the flakes (Comparative Example 4) was too high and the dielectric loss factor at frequencies >1 GHz was significantly too high.

Claims (16)

A use of a composite pigment as a LDS additive (laser direct molding additive) in a polymerizable composition, the composite pigment comprising from 95 to 100% by weight, based on the total weight of the composite pigment, of titanium dioxide (TiO ₂ ) and cerium-doped Tin dioxide ((Sb,Sn)O ₂ ) is composed. The use of claim 1, wherein the composite pigment has at least one core and a coating on the core. The use of claim 1, wherein the core has an isotropic shape. The use of the first aspect of the patent application, wherein the core is a spherical shape, a cube, in the form of a regular polyhedron or a semi-regular polyhedron having n faces, wherein n is in the range of 4 to 92 Within the range, or granular. The use of claim 1, wherein the core consists of TiO ₂ and has a coating comprising (Sb,Sn)O ₂ . The use of claim 1, wherein the core consists of (Sb,Sn)O ₂ and has a coating comprising TiO ₂ . The use of the first aspect of the patent application, wherein the ratio of the coating is from 20 to 70% by weight based on the total weight of the composite pigment. The use of claim 1, wherein the core has a particle size in the range of 0.001 to 10 microns. The use of claim 1 wherein the coating has a layer thickness in the range of from 1 to 500 nanometers. The use of the composite pigment as claimed in claim 1 Each consists of one or two or more primary particles, each of which has a core and a coating on the core. The use of claim 1, wherein the composite pigments each have a particle size in the range of 0.1 to 20 microns. The use of the first aspect of the invention, wherein the composite pigment is present in the polymerizable composition in a proportion ranging from 0.1 to 30% by weight based on the total weight of the polymerizable composition. The use of the first aspect of the invention, wherein the polymerizable composition comprises, in addition to the LDS additive, at least one organic polymerizable plastic and any filler and/or colorant. A polymerizable composition comprising at least one organic polymerizable plastic and an LDS additive, wherein the LDS additive is a composite pigment comprising from 95 to 100% by weight of titanium dioxide (TiO ₂ ) and doped with a total weight of the composite pigment It consists of antimony tin dioxide ((Sb,Sn)O ₂ ). The polymerizable composition according to claim 14, wherein the LDS additive is present in the polymerizable composition in a proportion of 0.1 to 30% by weight based on the total weight of the polymerizable composition. An object having a circuit structure fabricated by an LDS process, comprising a plastic substrate or a substrate having a coating containing a plastic and a metal conductor track on a surface of the substrate, wherein the plastic substrate or the plastic coating of the substrate Containing an LDS additive consisting of a composite pigment comprising from 95 to 100% by weight of titanium dioxide (TiO ₂ ) and cerium-doped tin dioxide ((Sb, Sn)O) based on the total weight of the composite pigment ₂ ) The composition.