An electrical interconnect structure comprising a diffusion barrier and a method of forming the structure over a semiconductor substrate. A bi-layer diffusion barrier is formed over the substrate. The barrier comprises a capturing layer beneath a blocking layer. The blocking layer is both thicker than the capturing layer and is unreactive with the capturing layer. A conductive layer, thicker than the blocking layer, is then formed over the barrier. While the conductive layer is unreactive with the blocking layer of the barrier, the conductive layer is reactive with the capturing layer of the barrier.

As the demand increases for cheaper, faster, lower power consuming integrated circuits, such as microprocessors, the transistor packing density of the integrated circuit must be similarly increased. To do so, the device dimensions of the integrated circuit are continually shrunk. Very large scale integration (VLSI) techniques have continually evolved to meet the increasing demand. All aspects of the integrated circuit must be scaled down to fully minimize the device dimensions. In addition to minimizing transistor dimensions, one must minimize the dimensions of the electrical interconnections which connect the transistors together on a microchip to form a complete circuit.
Currently, aluminum alloys are the most commonly used conductive materials for electrical interconnections in a VLSI integrated circuit. Aluminum and its alloys have been fully characterized for use as electrical interconnections, and much technology has been developed to aid in the formation of aluminum interconnections. Aluminum has very attractive features for use as an electrical interconnection, such as low electrical resistivity and strong adhesion to silicon dioxide. However, as VLSI dimensions reach into the deep-sub micron Ultra Large Scale Integration (ULSI) regime, the deficiencies of aluminum and its alloys become limiting factors in achieving superior performance. For example, as the width of electrical interconnections becomes narrower, even the low resistance of aluminum becomes non-negligible and begins to slow down the circuit. Additionally, with decreasing dimensions, design rules become increasingly restricted by aluminum interconnection reliability concerns such as electromigration, stress-induced void formation, hillock suppression, and current density limitations.
For these reasons, the microelectronics industry has recently migrated towards the investigation of more robust, more conductive metals for use in interconnection technology such as Copper (Cu). Cu is approximately 40% lower in resistivity than Al and is much more resistant to reliability problems such as electromigration. Unfortunately, Cu has been known to cause other reliability problems associated with the high rate of Cu diffusion through silicon substrates and dielectric films. One such problem is electrical shorting, wherein the Cu from one Cu interconnect line diffuses into an adjacent dielectric region, forming a conductive path to another Cu interconnect line. Another problem is transistor poisoning, wherein Cu diffuses into the underlying silicon substrate and causes Junction leakage along with reduced channel mobility in the transistor, thereby destroying the device. Therefore, to implement Cu as an interconnect material it has become necessary to develop methods for preventing Cu from diffusing through a semiconductor device.
One method for preventing copper diffusion through a semiconductor device is to employ a barrier between the copper interconnect and adjacent materials of the semiconductor device. FIG. 1 shows a cross section of a substrate 10 upon which a barrier 11 and a copper layer 12 are formed. Barrier 11 comprises a material which impedes the diffusion of copper from copper layer 12 into the underlying substrate 10. As shown, barrier 11 is not perfect. Barrier 11 comprises micro-defects 13 such as pinholes or voids in the film, and the barrier further comprises a number of grain boundaries, two of which ,14 and 15, are illustrated in FIG. 1. Micro-defect 13, along with grain boundaries 14 and 15, act as weak spots in the barrier, permitting copper from copper layer 12 to diffuse through to the underlying substrate 10. As shown, within micro-defect region 13 the copper of copper layer 12 comes into direct contact with substrate 10. Substrate 10 comprises silicon and silicon dioxide, through which copper will rapidly diffuse from the micro-defect in the barrier, particularly at elevated temperatures. Similarly, copper rapidly diffuses along grain boundaries of the barrier when subjected to elevated temperatures.
To better isolate copper layer 12 from the underlying substrate 10, the thickness of barrier 11 is simply increased. However, increasing the thickness of the barrier also increases the resistance of the resulting copper interconnect as illustrated in FIG. 2. FIG. 2 shows a cross section of a substrate 20 upon which an electrical interconnect comprising copper layer 23 and barrier 22 has been formed adjacent to dielectric material 21. As shown, the thickness of barrier layer 22 is large in comparison to the thickness of copper layer 23. It is necessary for barrier 22 to be thick enough to adequately prevent the diffusion of copper from copper layer 23 into either dielectric material 21 or substrate 20. Forming a thicker barrier reduces copper diffusion through micro-defects because the defects are more likely to be incorporated into the bulk of the barrier, thereby reducing diffusion paths through the defect. In addition, while a thicker barrier may still comprise grain boundaries leading from the upper to lower surface of the barrier, these boundaries are necessarily longer, thereby slowing copper diffusion and increasing the likelihood that a copper atom is blocked by, for example, a precipitate along the boundary. Because the grain boundaries are long, it would take a longer time for copper to diffuse through the length of these longer grain boundaries. While some copper atoms may successfully diffuse through these grain boundaries, it is expected that other reliability limitations of the integrated circuit will cause the device to fail by an alternate failure mechanism.
Note that as the thickness of barrier 22 increases, the volume which the highly conductive copper layer 23 occupies of the overall electrical interconnect decreases. Unfortunately, barrier 22 comprises materials which are at least 10 times more electrically resistive than copper, such as, for example, a dielectric such as silicon nitride. Therefore, increasing the barrier thickness while maintaining the overall width of the interconnect increases the total resistance of the electrical interconnect due to the reduction in volume that the low resistance copper material can occupy. The total width of the interconnect could be increased to counteract the increased resistance, but doing so would reduce the density of the integrated circuit.
Increasing the resistance of the electrical interconnect by increasing the thickness of barrier 22 defeats the advantages of employing copper as an interconnect material in the first place. As a result, the speed at which the integrated circuit operates is reduced. Thus, what is desired is a thin diffusion barrier which permits the low resistivity of copper or other interconnect material to be exploited in an electrical interconnect.

Diffusion barrier for electrical interconnects in an integrated circuit


A method for controlling the flow of data in a near field communication appliance having a plurality of secure elements is provided. The method includes receiving a first communication, sent by an external appliance, which is intended for an application located in one of a plurality of secure elements of the near field communication appliance. The method further includes determining which of the secure elements contains the application, and taking measures in order to ensure that a further communication exclusively between the external appliance and the secure element contains the addressed application. In addition, appropriate mobile terminals for NFC communication are disclosed.

It is expected that mobile electronic appliances will be increasingly equipped with additional radio frequency (RF) communication functions. By way of example, this relates to mobile telephones, portable media players, smartphones, personal digital assistants (PDAs), handheld games consoles, tablet computers, laptop computers, etc. Besides their conventional functions, these appliances will thus be capable of performing additional communication functions. The range of applications for RF communication functions includes, in particular, contactless chip card functions, such as bookings, payments, purchases and the like, but also simple terminal-to-terminal communication initiated by the user, for example for the exchange of photographs, MP3 songs or business cards. Such additional RF communication functions are increasingly being implemented using what is known as near field communication (NFC) engineering.
NFC engineering is a wireless short range connectivity technique which allows simple and secure two-way interactions between electronic appliances. This allows consumers to perform contactless transactions, access digital content and connect electronic appliances or apparatuses. In other words, NFC engineering allows contactless, bidirectional communication between appliances. These elements may be mobile telephones, computers, consumer electronics, cards, tags, signs, posters, washing machines and the like which are equipped with NFC. An appliance equipped with NFC engineering can basically operate in a read/write, peer-to-peer or card emulation mode.
NFC engineering is standardized as a contactless technique in the 13.56 MHz frequency band. The ISO 14443 standard is a basic building block for a large part of the near field operations. NFC engineering is generally compatible with at least the type A and type B ISO 14443 standards. The components of an NFC session comprise initiators and targets. The initiator is the element which starts and manages the communication and the interchange of data. The target responds to requests from the initiator. A feature of NFC engineering is that elements can act either as an initiator or as a target. NFC engineering requires a dedicated RF chipset and an antenna to be integrated in the mobile element.
In a known configuration, the ISO 14443 standard is mapped in a mobile terminal onto a contact-based, transparent interface between, by way of example, an NFC frontend and a secure element, the secure element being in the form of a smartcard, for example. When physical proximity between the terminal and a contactless external terminal is set up, for example in order to make an electronic payment, RF communication is used to set up communication between the terminal and the mobile terminal. On the basis of the ISO 14443 standard, the communication between the wireless terminal and the secure element on which an application for handling the payment transaction is hosted is usually transparent in this case. This means that the NFC frontend as an interposed element passes the data stream through between the secure element (SE) and the external wireless terminal in both communication directions almost without alteration. In this case, mere decoding is not regarded as a break in the transparency so long as the transported information is not altered. This transparency is advantageous because, inter alia, it increases the communication speed as a result of absent intermediate steps in the NFC frontend, and also the security of the overall process.
It is to be expected that commercially available terminals, such as mobile telephones, will each increasingly be equipped with multiple secure elements, or at least the option of using multiple elements, in a foreseeable time. The reason for this, inter alia, is that there has been no internationally recognized industrial standard to date which provides a standard format for a secure element for the different market participants in the area of near field communication. By way of example, these include manufacturers of mobile terminals such as mobile telephones and tablet computers, etc., mobile radio providers, providers of payment systems, etc. The individual players have different channels and options for bringing the hardware of their payment systems to the customers. In the case of a mobile telephone manufacturer, this may be, by way of example, the installation of a complete near field communication system, including an NFC frontend and a permanently installed, i.e. soldered, for example, secure element. By contrast, the mobile radio provider is usually totally unable, or has only very limited ability, to influence the hardware of the terminal and will therefore provide a secure element, for example, in the form of or as a combination with a SIM card, which, as known from conventional mobile radio technology, the end user inserts into his mobile telephone, e.g. instead of his conventional previous SIM card without a secure element. A further option is a secure element in the form of a chip card (smartcard) or SD card, for example, which is inserted into a card slot in the terminal, that is to say in the mobile telephone, handheld computer or tablet computer, for example.
ISO standard 14443 defines the communication between a secure element and an NFC frontend. One way of providing, by way of example, a plurality of payment systems in a mobile terminal with near field communication capability, such as a mobile telephone, is to provide the relevant applications associated with the different payment systems on the same secure element (multi-application secure element). However, this provides only little flexibility insofar as, by way of example, the provider of a payment system may first need to come to an agreement with that market player which controls access to the secure element of the relevant terminal, for example a mobile radio provider in the case of a SIM card. Depending on the market structure and competition circumstances, this may be uneconomical, complicated or ultimately impossible for the provider of a payment system. Technical incompatibilities between the relevant applications and certain types of secure elements may be a further technical and economic obstacle.
Against this background, there is a need for methods and apparatuses which allow different applications for near field communication to be implemented in a terminal without being reliant on access to a particular secure element.

Methods and appliances for forwarding communication between external appliances and secure elements using an interposed element and near field communication (NFC)


Polypeptides and multimeric polypeptides capable of binding interferon α and/or interferon β which are useful therapeutically in methods of treating interferon α/β-related conditions or diseases.

1. Field of the Invention
The invention encompasses interferon α- and/or β-binding fusion proteins, as well as therapeutic uses of such polypeptides for inhibiting interferon α and/or β activity, especially the interferon α proteins.
2. Description of Related Art
It has previously been reported that a humanized anti-interferon α antibody neutralizes human leukocyte interferon and is beneficial in rodent models of insulin-dependent diabetes mellitus (IDDM) (Chuntharapai et al. (2001) Cytokine 15(5):250-260).

Interferon-α/β binding fusion proteins and therapeutic uses thereof


A method and a device for power transmission from a motor having a supercharging assembly, particularly a supercharged diesel-engine (7), to a gear (3) with a surface water driving propeller mechanism (4) mounted in a boat of the planing variety and preferably with a large propeller with a large pitch. A turbine coupling (10), which can be filled to a variable extent, is mounted between the supercharged motor (7) and the gear (3). The motor is designed to drive the pump portion (15) of the turbine coupling (10), and the turbine portion (17) of the turbine coupling (10) is connected to the input shaft (6) of the gear (3). The turbine coupling (10), when the boat is started, is emptied completely or partially, in such a way that it is at least partially disconnected from the gear. The motor is then accelerated to such a speed that the supercharging assembly of the motor (7) is connected. The turbine coupling is subsequently quickly filled with hydraulic medium, so that the propeller mechanism (4) is influenced by the substantially maximum output of the motor, caused by the supercharging assembly. When the boat has reached its planing speed, the motor speed in the desired way is reduced and/or the extent of filling of the turbine coupling is reduced, but no to a lower speed than that the boat will be propelled with a speed which is somewhat larger than the planing limiting speed. The invention also relates to the use of a turbine coupling in planing boats having gears of the above-described variety.

A surface water driving propeller assembly is a type of boat gear, in which the gear is mounted in the stern of preferably planing boats and in which the propeller assembly with its gear body projects essentially horizontally backwards (when the boat is planing) outside the stern, and which drives a propeller with an essentially straight shaft. Gears of this type are mounted in such a way, that the gear housing, when the boat is driven at speeds above a certain minimum speed, which corresponds to the lowest planing speed, is substantially parallel with the water surface and close to the water surface and in which the propeller assembly with its propeller dips into the water with only about half its height. Some propeller blades are then positioned in water, whereas other propeller blades are being ventilated in the air above the water surface. Propellers designed for this type of gear are consequently larger and/or have a larger pitch than conventional underwater-working propellers, usually at least a 15% larger diameter and pitch, because only some of the propeller blades exert a propulsion power below the water surface, and also the propellers must rotate considerably slower than conventional underwater-working propellers in order to attain the best driving conditions. Various examples of gears with surface water driving propellers are shown in European patent specification 37.690 (Arneson) or in Swedish patent accplications 8804295-7 and 8804296-5 (Thiger).
When the boat is immobile and before it has accelerated to its planing speed, all the propeller assembly and the better part of the gear body are positioned below the water surface, and a very large force from the motor is required, if the motor is to be able to accelerate the boat up to its planing speed, at which speed the propellers will be able to start working in the desired way, particularly because the propeller assembly is considerably larger and has a larger pitch than conventional underwater-working propellers.
Gears with propeller assemblies of the surface water-driving type are very different from underwater-driving propellers, i.a. since the propeller in the planing speed works in air as much as 50-70% and is considerably larger and usually has a considerably larger pitch than the corresponding underwater-working propellers and since the propeller drives the boat through a pressure force from the rear side of the propeller, while conventional underwater-working propellers propel the boat through a suction force on the front side of the propeller in substantially the same way as a sailing boat, when the wind comes ahead to port, is propelled through the suction force from the front side of the sail This is the main reason for the absence of a cavitation and a suction downwards of air from the water surface as far as a surface water-driving propeller goes, which is quite common as to conventional underwater-working propellers. Thus, it is possible as to surface water-driving propellers, already when the boat is immobile, to exert an initial force on the propeller, which corresponds to a maximum torque from the motor. In this way a boat with a surface water-driving propeller can be accelerated very strongly, and in practice such propeller assemblies, in comparison with underwater-driving propellers, prove to attain a speed increase of as much as 30-40%.
When motors, particularly Otto-engines, without turbo-charging assemblies are used, the required large initial force can often be obtained through a large gas input, but when using driving motors provided with supercharger assemblies such as turbo- or compressor-charge-assemblies, particularly supercharged Diesel-engines (turbo-Diesel engines), problems arise, which have so far been very difficult to solve. The Diesel-engines to be sure normally have a fairly small speed range and a low maximum top speed and have a relatively weak acceleration capacity from low speeds. Supercharged Diesel-engines also to be sure do not obtain their higher power range, made possible by means of the turbo-assembly, before the supercharger assembly has been connected, and this is not done before the speed is relatively high. Thus, when Diesel-engines are used, particularly supercharged Diesel-engines, in boats with gears of the above-mentioned surface water-driving type, the view has so far been that it is necessary to use an oversized engine, which is able to accelerate the boat to its planing speed within a reasonable period of time, or that it is necessary to use other, maybe expensive and complicated solutions in order to obtain a high driving motor output already from the start.
Also as far as underwater-driving propellers go, the propeller to be sure working constantly and in its entirety against water, the corresponding problem may arise but not to the same extent as in the case of surface water-driving propellers, where the propeller works against water only from the immobile condition of the boat and up to its planing speed, while the active surface of the propeller against water when the speeds are higher than the planing speed is only 40-60% of the total propeller-surface, while the remaining part of the surface works in air and substantially without any reaction requirement. As far as such underwater-driving propellers go, the propeller proportionally being smaller than surface water-driving propellers and allowed to work with a considerably higher speed than surface water-driving propellers, the above-mentioned problems could be solved by feeding air downwards to or allowing air to be sucked downwards to the propeller, in order to make the propeller "spin" and with a maintained high speed accelerate the boat to its planing speed. In certain cases this problem has also been solved by equiping the boat with an undersized propeller in order to allow a "spinning," when a cavitation and an air suction downwards take place.
Swedish document 451.449 (Brunswick Corporation), laid open to public inspection, describes a system designed to increase the acceleration of a boat by connecting between the motor and the gear a torque-boosting hydrodynamic torque converter. Such a torque converter allows a certain slippage between the pump and the turbine, often a slippage of almost 20%, which allows an acceleration of the motor, before the propeller starts to drive fully, and in this way the motor will already from the start of the acceleration cycle have a speed, which at least to some extent has approached the highest output-speed of the motor. The slippage in the torque converter is limited i.a. by the use of stationary guide rails and by the shape of the pump and turbine blades and it allows only a certain limited motor speed increase, before the successively increased hydraulic pressure in the torque converter makes the propeller drive with a substantial force. However, due to the comparatively large slippage of almost 20% between the pump and the turbine and the guide rails respectively a complete motor output on the propeller cannot be attained, and due to the risk of overheating etc. also such a slippage cannot be allowed for an extended period of time Thus, the hydrodynamic torque converter in the above-mentioned public inspection-document is according to this document designed with a lockable mechanical coupling, a so called lock-up clutch, which is connected when the motor reaches a certain predetermined speed and is disconnected when the motor speed is lower than this predetermined speed.
A device of the above-described type has some drawbacks, which make it unserviceable for gears with surface water-driving propellers and for motors of the type, which requires an almost maximum speed, before the motor output starts being transmitted to the propeller, e.g. motors having a surcharge assembly, so called turbo-motors, and this is particularly true for Diesel-engines but also for Otto-motors. In boats with such motors, for which the motor output has been calculated with regard to the maximum output at a high motor speed, said device cannot be used at all, since this high motor speed cannot be obtained before the driving force is transmitted to the propeller. Also, the device is complicated and expensive, there is a great risk of overheating and an overheating of the hydraulic medium due to the extensive slippage, special pump assemblies are required for a connection and a disconnection of the lock-up clutch, and there is a risk of slippage also in the lock-up clutch at high motor speeds and outputs.

Method and apparatus for power transmission to a surface driving propeller mechanism and use of a turbine between the driving engine and propeller mechanism


The method is for managing the operation of a wireless communication device including several different communication modules respectively adapted to operate according to several given communication protocols including a UWB module operating according to a UWB protocol based on an OFDM modulation scheme. The method includes controlling the UWB module for scanning a chosen frequency band, and managing a communication to be performed by the device on the basis of the scanning result.

Today's wireless systems are mainly based on a fixed frequency allocation to a specific service. For example, the band around 900 MHz and around 1800 MHz are exclusively reserved for the use of Global System for Mobile (GSM). Other bands are reserved for other kinds of wireless communication and navigation systems.
Among the other types of wireless systems, for example, are those using mobile radio standards such as GSM, Universal Mobile Telecommunications System (UMTS), code-division multiple access-2000 (CDMA2000), Wideband Code Division Multiple Access (WCDMA), Enhanced Data rates for GSM Evolution (EDGE); Multi-Carrier Code Division Multiple Access (MC-CDMA), and non coordinated communication systems such as WLAN (Wireless Local Area Network) or WPAN (Wireless Personal Area Network) adapted to work for example according to a UWB (Ultra Wide Band) technology. Also, WIMAX devices (Worldwide Interoperability for Microwave Access) are fixed wireless devices, operating for example with a bandwidth of 20 MHz at a central frequency of 3.5 GHz. The co-location within the same device of different communication modules adapted to operate according to different communication protocols or standards, has been already contemplated.
However, in such existing systems, the normal receiver circuitry or means are used for performing a spectrum sensing. In other words, each communication module is sequentially switched into a scanning mode and can then get an idea of the frequency allocation in its surrounding. However, this sequential scanning is in general slow and thus very time consuming. Furthermore, the time resolution of this conventional method is limited due to the limited sampling time of the used systems.
There is a need to scan a complete frequency band of interest in a single operation without changing the operational mode of the wireless device. There is also a need to improve the resolution of the spectrum analyzing.

Method of managing the operation of a wireless communication device and corresponding wireless device


A dispenser comprises a container having a first aperture therein and a first closure element for sealingly closing the first aperture wherein the container has a second aperture and a second closure element for closing said second aperture, the second closure element including a pressing element operable to press inwardly towards the second aperture, a blister pack, locating element locating the blister pack to span across the second aperture and sealing element sufficient to ensure the second aperture is sealingly closable against leakage of the intended contents of the dispenser. The construction and arrangement is such that in end use the container holds a first substance and the blister pack holds a second substance and when the pressing element is pushed the blister pack is ruptured enabling the mixing of the contents thereof with those of the container.

When the dispenser is in the form of a liquid containing bottle, bottle caps, designed to retain an additive such as a powder or tablet or liquid and to subsequently release the additive into an attached bottle upon manipulation by a user, are known in the pharmaceutical industry and more recently in the sports drinks industry. Examples of such discharge caps are disclosed in WO98/40289, WO00/27717, WO98/00348 and WO93/14990. Many of the prior art mechanisms are cumbersome and their size can cause difficulties in the packaging, transportation and display of bottles. Their bulk may also detract from the appearance of the product which is of importance in relation to certain products such as sports drinks. Others may be complex and difficult or costly to manufacture.


The present invention provides for the use of film-forming aqueous formulations comprising in dispersed form at least one crosslinked copolymer P for coating shaped mineral articles and for a method of coating shaped mineral articles, said copolymer P comprising in copolymerized form

The present invention relates to the use of aqueous film-forming formulations comprising at least one crosslinked copolymer P in dispersed form for coating shaped mineral articles and to a process for coating shaped mineral articles.
By shaped mineral articles are meant, here and below, shaped articles which comprise mineral aggregates, such as sand, clay, crushed rock, etc., and a mineral binder, and also, if desired, customary additives. Mineral binders are common knowledge. They comprise, for example, finely divided inorganic substances, such as lime, gypsum, clay and/or cement, which can be shaped in the wet state and which, when left to themselves, harden after a certain time, either in air or underwater, with or without the action of elevated temperature, to give a stonelike mass.
The aggregates consist in general of granular or fibrous, natural or synthetic stone (gravel, sand, mineral fibers), including in special cases metals as well, or organic material or mixtures of said aggregates, with grain sizes or fiber lengths that are adapted in a conventional manner to the specific application intended. In many cases, color pigments are also used as aggregates, for the purpose of coloring.
Examples of shaped mineral articles that can be coated in accordance with the invention are concrete pipes, as used to transport waste water, for example, concrete roof tiles or curb stones, steps, base slabs, and plinth tiles based on mineral binders, and also fiber cement slabs, i.e. flat shaped mineral articles which may be filled with inorganic or organic fibers, such as polyester fibers or nylon fibers, for example.
A disadvantage of shaped mineral articles is that under the influence of weathering (especially exposure to water) the cationic constituents, such as Ca2+, are leached out over the course of time, reducing the strength of the articles. This is often accompanied by efflorescence phenomena. These are probably attributable to the fact that cations with a valency of two or more, such as Ca2+, react with the carbon dioxide from the air and so form, on the surface of the shaped mineral articles, white spots of lime. Efflorescence may also appear during the hardening of freshly prepared shaped mineral articles.
In order to avoid these disadvantages, the shaped mineral articles are often provided with a protective coat. For this purpose use is now generally made of aqueous coating systems whose film-forming constituent (binder) comprises an aqueous polymer dispersion. Customary binders include styrene-acrylate copolymers, vinyl acetate homo- and copolymers, pure acrylates and the like (cf. for example DE 21 64 256). However, the coatings obtainable with these binders are unable to prevent satisfactorily the emergence of the cationic constituents (efflorescence). Furthermore, such coatings are easily soiled.
It has proven possible to improve the protection of shaped mineral articles from the efflorescence described above by means, inter alia, of coating compositions based on styrene-acrylate dispersions or all-acrylate dispersions of EP-A-469 295 and DE-A-195 14 266. EP-A-469 295 recommends for this purpose the use of a specific anionic emulsifier, and DE-A-195 14 266 the use of polymers whose incorporated monomers include specific, sulfonate-functional monomers, while DE 197 49 642.3 recommends using polymers containing itaconic acid in copolymerized form.
EP-A-279 067 discloses clear varnishes for coating wood which comprise alkyl methacrylate-based polymers crosslinked with divinylaromatics, diol di(meth)acrylates or diallyl phthalates. On weathering, such coatings lose their gloss and become brittle over time. DE-198 10 050.7 discloses the use of aqueous, film-forming formulations based on alkyl methacrylate copolymers which contain not more than 1% by weight of monomers having two or more ethylenically unsaturated double bonds. There is no mention whatsoever of suitable polyunsaturated monomers, and the examples are devoid of polyethylenically unsaturated monomers.
It is an object of the present invention to provide coatings for shaped mineral articles which feature improved gloss stability and long-term durability in outdoor use, provide effective protection against efflorescence, and show good adhesion properties to mineral substrates.
We have found that this object is achieved and that aqueous formulations comprising copolymers P as film-forming constituent, which are composed essentially of (meth)acrylates and/or vinylaromatics and include from 0.01 to 1.9% by weight of specific diethylenically unsaturated (meth)acrylates having a crosslinking action result in coatings of increased gloss stability, high long-term durability, and good adhesion properties in outdoor use.
The present invention therefore provides for the use of aqueous film-forming formulations comprising in dispersed form at least one copolymer P composed of ethylenically unsaturated monomers, said copolymer P comprising in copolymerized form
a) from 80 to 99.89% by weight of at least one monomer selected from esters of acrylic acid with C1-C12-alkanols, esters of methacrylic acid with C1-C8-alkanols and monovinylaromatics,
b) from 0.1 to 19.99% by weight of at least one monomer different from a), selected from xcex1,xcex2-ethylenically unsaturated C3-C6 monocarboxylic and dicarboxylic acids, the amides, N-alkyl amides and nitriles of these carboxylic acids, monoesters of xcex1,xcex2-monoethylenically unsaturated C4-C8 dicarboxylic acids with C1-C12-alkanols, vinyl esters of aliphatic C1-C18 carboxylic acids, xcex1,xcex2-monoethylenically unsaturated sulfonic acids and sulfonic esters, and xcex1,xcex2-monoethylenically unsaturated siloxanes, and
c) from 0.01 to 1.9% by weight of at least one crosslinking monomer selected from esters of acrylic or methacrylic acid with linear or branched C3-C6-alkenols, cyclic C5-C7-alkenols and polycylic C7- to C12-alkenols,
the total content of monomers bearing free acid groups, based on the total amount of all copolymerized monomers, being less than 5% by weight, for coating shaped mineral articles.
Examples of suitable esters of acrylic acid with C1-C12-alkanols are methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-butyl, isobutyl, tert-butyl-, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, n-pentyl, 1-methylpentyl, 2-methylpentyl, 2-ethylpentyl, n-hexyl, 1-methylhexyl, 2-methylhexyl, 2-ethylhexyl, n-heptyl, 1-methylheptyl, 2-methylheptyl, 2-propylheptyl, n-octyl, 1-methyloctyl, 2-methyloctyl, n-decyl and n-dodecyl acrylate. Preference is given to the esters of acrylic acid with alkanols having 2 to 8 carbon atoms, i.e., ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl, n-hexyl and 2-ethylhexyl acrylate. Of these, n-butyl acrylate and 2-ethylhexyl acrylate are particularly preferred.
Examples of suitable esters of methacrylic acid with C1-C18-alkanols are methyl, ethyl, n-propyl, isopropyl, n-butyl-, 2-butyl, isobutyl, tert-butyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, n-pentyl, 1-methylpentyl, 2-methylpentyl, 2-ethylpentyl, n-hexyl, 1-methylhexyl, 2-methylhexyl, 2-ethylhexyl, n-heptyl, 1-methylheptyl, 2-methylheptyl and n-octyl methacrylate. Preference is given to the esters of methacrylic acid with alkanols having 1 to 4 carbon atoms, i.e., methyl, ethyl, n-propyl, isopropyl, n-butyl and tert-butyl methacrylate. Of these, methyl methacrylate and n-butyl methacrylate are particularly preferred.
Examples of suitable vinylaromatic monomers are styrene, xcex1-methylstyrene, o-chlorostyrene and vinyltoluene; styrene is preferred.
Based on the total monomer amount, the copolymers P contain preferably from 90 to 98.99% by weight and, with particular preference, from 95 to 98.49% by weight of the abovementioned monomers (monomers a)) in copolymerized form.
In addition to the abovementioned monomers, the copolymers P include, based on the total monomer amount, from 0.1 to 19.99% by weight, preferably from 1.0 to 9.9% by weight and, with particular preference, from 1.5 to 4.99% by weight of at least one different monomer (monomer b)) selected from xcex1,xcex2-ethylenically unsaturated C3-C6 monocarboxylic acids, such as acrylic acid, methacrylic acid, crotonic acid, vinylacetic acid, acrylamidoglycolic acid and methacrylamidoglycolic acid, xcex1,xcex2-monoethylenically unsaturated C4-C6 dicarboxylic acids, such as maleic acid, fumaric acid, itaconic acid and citraconic acid, the amides of the abovementioned unsaturated mono- and dicarboxylic acids, especially acrylamide and methacrylamide, the N-alkyl amides of the abovementioned unsaturated mono- and dicarboxylic acids and the nitriles of the abovementioned unsaturated mono- and dicarboxylic acids, such as acrylonitrile and methacrylonitrile, vinyl esters of aliphatic C1-C18 carboxylic acids, such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, vinyl hexanoate, vinyl 2-ethylhexanoate, vinyl decanoate, vinyl pivalate, vinyl laurate, vinyl stearate, and commercial monomers VEOVA(copyright) 5-11 (VEOVA(copyright) X is a tradename of Shell and stands for vinyl esters of xcex1-branched aliphatic carboxylic acids having x carbon atoms, which are also known as Versatic(copyright) X acids), monoesters of xcex1,xcex2-monoethylenically unsaturated C4-C8-dicarboxylic acids with C1-C12-alkanols, such as monomethyl maleate and mono-n-butyl maleate, xcex1,xcex2-monoethylenically unsaturated sulfonic acids, such as vinylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-acryloxyethanesulfonic acid and 2-methacryloxyethanesulfonic acid, 3-acryloxy- and 3-methacryloxypropanesulfonic acid and vinylbenzenesulfonic acid and the methyl, ethyl and n-butyl esters thereof, and xcex1,xcex2-monoethylenically unsaturated siloxanes, such as vinyltrialkoxy silanes, e.g., vinyltrimethoxysilane, alkylvinyldialkoxysilanes or (meth)acryloxyalkyltrialkoxysilanes, e.g., (meth)acryloxyethyltrimethoxysilane, (meth)acryloxypropyltrimethoxysilane. If the copolymers P include xcex1,xcex2-monoethylenically unsaturated siloxanes, they are generally used in amounts of up to 1% by weight, preferably from 0.05 to 0.5% by weight, based on the total monomer amount. Preferred monomers b) are acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, acrylamide, methacrylamide, vinyl acetate, vinylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, and vinyltrimethoxysilane. Particular preference is given to acrylic acid, methacrylic acid, maleic acid, acrylamide, methacrylamide, acrylonitrile, and methacrylonitrile.
Based on the total amount of monomers, the copolymers P preferably contain less than 4% by weight, with particular preference from 0.1 to 3.0% by weight and, with very particular preference, from 0.2 to 2.0% by weight of monomers bearing free acid groups and/or amides of xcex1,xcex2-ethylenically unsaturated carboxylic acids in copolymerized form.
In addition, the copolymers P contain from 0.01 to 1.9% by weight, preferably from 0.05 to 1.5% by weight, of at least one crosslinking monomer selected from esters of acrylic acid or methacrylic acid with linear or branched C3-C6-alkenols, such as allyl acrylate, methallyl acrylate, 2-buten-1-yl acrylate, 3-buten-1-yl acrylate, 3-methyl-2-buten-1-yl acrylate, 3-methyl-3-buten-1-yl acrylate, 2-methyl-3-buten-2-yl acrylate, 5-hexen-1-yl acrylate, allyl methacrylate, methallyl methacrylate, 2-buten-1-yl methacrylate, 3-buten-1-yl methacrylate, 3-methyl-2-buten-1-yl methacrylate, 3-methyl-3-buten-1-yl methacrylate, 2-methyl-3-buten-2-yl methacrylate, 5-hexen-1-yl methacrylate, from esters of acrylic acid or methacrylic acid with cyclic C5-C7-alkenols, such as cyclohexenyl acrylate, cyclohexenyl methacrylate, methylcyclohexenyl acrylate and methylcyclohexenyl acrylate, and from esters of acrylic acid or methacrylic acid with polycyclic C7- to C12-alkenols, such as norbornenyl acrylate, tricyclodecenyl acrylate, norbornenyl methacrylate and tricyclodecenyl methacrylate. Preference is given to allyl acrylate, methallyl acrylate, tricyclodecenyl acrylate, allyl methacrylate, methallyl methacrylate and tricyclodecenyl methacrylate, particular preference to allyl acrylate and allyl methacrylate, and very particular preference to allyl methacrylate.
It is preferred to use formulations comprising a copolymer P wherein the monomers a) include at least one ester of acrylic acid with linear and branched C4-C8-alkanols and at least one further monomer selected from the esters of methacrylic acid with C1- and linear C2-C4-alkanols and vinylaromatics.
Very particular preference is given to the use of formulations comprising a copolymer P wherein the monomers a) are composed essentially of n-butyl acrylate and at least one further monomer selected from methyl methacrylate, n-butyl methacrylate and styrene.
Customarily, the copolymer P has a glass transition temperature in the range from xe2x88x9210 to +80xc2x0 C., and preferably in the range from 0 to +60xc2x0 C. It should be borne in mind here that a high-quality coating is only obtained when the aqueous formulation of the film-forming copolymer P has a minimum film-forming temperature which is below the application temperature. This minimum film-forming temperature depends in turn on the glass transition temperature Tg of the copolymer P (see Ullmann""s Encyclopedia of Industrial Chemistry, 5th ed., Vol. A 21, 1992, p. 169). The minimum film-forming temperature can be lowered by adding what are known as external plasticizers of low volatility to the aqueous formulation, such as esters of phthalic acid, and/or highly volatile, low-boiling organic solvents, as film-forming auxiliaries.
It has proven advantageous to tailor the formulations that are employed in accordance with the invention to their specific end applications by choosing an appropriate glass transition temperature for the copolymer P. For instance, a glass transition temperature Tg for the copolymers P of above 0xc2x0 C., and in particular above +10xc2x0 C., has been found advantageous for the coating of concrete slabs. In this embodiment of the invention it is preferred not to exceed a Tg of +50xc2x0 C. In the case of fiber cement slabs, which both can be coated at elevated temperature and are intended to have a high blocking resistance, on the other hand, a glass transition temperature of above +20xc2x0 C., and in particular above +30xc2x0 C., has been found advantageous. The glass transition temperature Tg referred to here is the midpoint temperature determined in accordance with ASTM D 3418-82 by differential thermal analysis (DSC) (cf. Ullmann""s Encyclopedia of Industrial Chemistry, 5th edition, Volume A 21, VCH Weinheim 1992, pp. 169 and also Zosel, Farbe und Lack 82 (1976), pp. 125-134, see also DIN 53765).
It proves useful in this context to estimate the glass transition temperature Tg of the copolymer P. According to Fox (T. G. Fox, Bull. Am. Phys. Soc. (Ser. II) 1, 123 [1956] and Ullmanns Enzyklopxc3xa4die der technischen Chemie, Weinheim (1980), pp. 17, 18) the glass transition temperature of copolymers with a low degree of crosslinking, at high molar masses, is given in good approximation by       1          T      g        =                    X        1                    T        g        1              +                  X        2                    T        g        2              +          …                    xe2x80x83                                    X          n                          T          g          n
where X1, X2, . . . , xn are the mass fractions of the monomers 1, 2, . . . , n, and Tg1, Tg2, . . . , Tgn the glass transition temperatures of their homopolymers, in degrees Kelvin. The latter are given, for example, in Ullmann""s Encyclopedia of Industrial Chemistry, VCH, Weinheim, Vol. A 21 (1992) p. 169 or in J. Brandrup, E. H. Immergut, Polymer Handbook 3rd ed., J. Wiley, New York 1989.
From what has been said above it is clear that the glass temperature Tg of the copolymer P can be adjusted either by means of an appropriate principal monomer a) having a glass temperature within the desired range or by combining at least one monomer of high glass transition temperature and at least one monomer of low glass transition temperature.
In a preferred embodiment of the present invention the constituent monomers P of the polymer comprise at least one monomer whose homopolymer, for the limiting case of a very high molecular weight, has a glass transition temperature Tg greater than 30xc2x0 C., examples being styrene, xcex1-methylstyrene, methyl methacrylate, ethyl methacrylate, n- and isopropyl methacrylate, n-, iso- and tert-butyl methacrylate, and tert-butyl acrylate, and at least one monomer whose homopolymer has a glass transition temperature Tg less than 20xc2x0 C., examples being C1-C12-alkyl acrylates, vinyl Versatates, especially ethyl acrylate, n-butyl acrylate and 2-ethylhexyl acrylate. Particular preference is given to monomer combinations of monomers with Tg greater than 30xc2x0 C. and monomers with Tg less than 20xc2x0 C. which comprise styrene and/or methyl methacrylate alone or together with tert-butyl acrylate, n-butyl methacrylate and/or tert-butyl methacrylate as monomers with Tg greater than 30xc2x0 C. and also n-butyl acrylate and/or 2-ethylhexyl acrylate as monomers with Tg less than 20xc2x0 C. The weight ratio of monomers with Tg greater than 30xc2x0 C. to monomers with Tg less than 20xc2x0 C. is usually within the range from 20:80 to 80:20 and in particular in the range from 35:65 to 65:35. Typical monomer combinations are:
styrene: n-butyl acrylate in a weight ratio of 35:65-80:20,
styrene: 2-ethylhexyl acrylate in a weight ratio of 35:65-80:20,
methyl methacrylate: n-butyl acrylate in a weight ratio of 40:60-80:20,
methyl methacrylate: 2-ethylhexyl acrylate in a weight ratio of 35:65-80:20,
and also ternary and quaternary monomer mixtures in which some of the styrene is replaced by methyl methacrylate and/or n-butyl methacrylate, or some of the n-butyl acrylate by 2-ethylhexyl acrylate, examples being:
methyl methacrylate: styrene: 2-ethylhexyl acrylate in a weight ratio of 20:20:60,
n-butyl methacrylate: styrene: 2-ethylhexyl acrylate in a weight ratio of 35:10:55,
methyl methacrylate: n-butyl methacrylate: n-butyl acrylate in a weight ratio of 30:35:35
styrene: n-butyl acrylate: 2-ethylhexyl acrylate in a weight ratio of 50:25:25 and
styrene: methyl methacrylate: n-butyl acrylate 2-ethylhexyl acrylate in a weight ratio of 20:20:30:30.
The copolymers P present in the aqueous formulations that are employed in accordance with the invention can in principle be prepared by any conceivable method for the free-radical copolymerization of ethylenically unsaturated monomers, for example, by solution, precipitation, bulk, emulsion or suspension polymerization. The free-radical aqueous emulsion polymerization of the abovementioned monomers is preferred, in the presence of at least one free-radical polymerization initiator and, if desired, one or more surface-active substances, since in this case the copolymers P are obtained in the form of an aqueous dispersion. Using other polymerization methods it may be necessary, if appropriate, to carry out subsequent conversion of the copolymers P to an aqueous dispersion (secondary dispersion).
The film-forming aqueous formulations, according to the invention, contain the copolymer P in the form of an aqueous dispersion. The particles of copolymer in this dispersion can have average sizes in the range from 50 to 1000 nm. Methods of adjusting the polymer particle size are known, for example, from EP-A-126 699, EP-A-567 881, EP-A-567 819, DE-A-31 47 008 and DE-A-42 13 967.
Suitable free-radical polymerization initiators are all those that are able to trigger a free-radical aqueous emulsion polymerization; they may be peroxides, such as alkali metal peroxodisulfates or hydrogen peroxide, or azo compounds. It is preferred to use redox initiator systems, which are composed of at least one organic reducing agent and at least one peroxide and/or hydroperoxide, for example tert-butyl hydroperoxide with a sulfur compound, such as the sodium salt of hydroxymethanesulfinic acid, sodium sulfite, sodium disulfite, sodium thiosulfate or acetone bisulfite, or hydrogen peroxide with ascorbic acid. It is also possible for this purpose to use redox initiator systems containing a small amount of a metal compound which is soluble in the polymerization medium and whose metallic component is able to exist in two or more valence states, an example being iron(II) sulfate. Likewise preferred initiators are alkali metal peroxodisulfates, such as sodium peroxodisulfate or ammonium peroxodisulfate. The amount of free-radical initiator systems employed, based on the overall amount of monomers to be polymerized, is preferably from 0.05 to 2% by weight, more preferably from 0.1 to 1% by weight.
Surface-active substances suitable for conducting the emulsion polymerization are the emulsifiers and protective colloids that are normally employed for such purposes. The surface-active substances are usually employed in amounts of up to 10% by weight, preferably from 0.5 to 5% by weight, and in particular from 1 to 4% by weight, based on the monomers to be polymerized.
Examples of suitable protective colloids are polyvinyl alcohols, starch derivatives and cellulose derivatives, or vinylpyrrolidone copolymers. A detailed description of further suitable protective colloids is given in Houben-Weyl, Methoden der organischen Chemie, Volume XIV/1, Makromolekulare Stoffe [Macromolecular Substances], Georg-Thieme-verlag, Stuttgart 1961, pp. 411-420. Suitable emulsifiers are mentioned in Houben-Weyl, Methoden der organischen Chemie, Volume XIV/1, Makromolekulare Stoffe [Macromolecular Substances], Georg-Thieme-Verlag, Stuttgart 1961, pp. 192-208. Mixtures of emulsifiers and/or protective colloids can also be used.
As surface-active substances it is preferred to use exclusively emulsifiers, whose relative molecular weights, in contradistinction to the protective colloids, are usually below 2000. They are preferably anionic or nonionic in nature. The anionic emulsifiers include alkali metal and ammonium salts of alkyl sulfates (alkyl: C8-C12), of sulfuric monoesters of ethoxylated alkanols (EO units: 2 to 50, alkyl: C12 to C18) and ethoxylated alkylphenols (EO units: 3 to 50, alkyl: C4-C9), of alkylsulfonic acids (alkyl: C12-C18) and of alkylarylsulfonic acids (alkyl: C9 to C18). The anionic surface-active substances also include compounds of the formula I,
where R1 and R2 are hydrogen or C4-C24-alkyl but are not both hydrogen, and X and Y can be alkali metal and/or ammonium ions. The compounds I are common knowledge, for example from EP-A 469 295. Particularly advantageous compounds I are those in which X and Y are sodium, R1 is a branched alkyl of 12 carbons and R2 is hydrogen or is the same as R1. Use is frequently made of technical-grade mixtures containing from 50 to 90% by weight of the monoalkylated product, an example being Dowfax(copyright) 2A1 (trademark of Dow Chemical Company).
Suitable nonionic emulsifiers are araliphatic or aliphatic nonionic emulsifiers, examples being ethoxylated mono-, di- and trialkylphenols (EO units: 3 to 50, alkyl: C4-C9), ethoxylates of long-chain alcohols (EO units: 3 to 50, alkyl: C8-C36), and polyethylene oxide/polypropylene oxide block copolymers.
It is preferred to employ anionic emulsifiers, especially emulsifiers of the formula I, or combinations of at least two anionic or at least one anionic with at least one nonionic emulsifier.
The molecular weight of the polymers can be adjusted by adding small amounts, generally up to 2% by weight based on the monomers to be polymerized, of one or more molecular weight regulators, examples of these being organic thio compounds, allyl alcohols and aldehydes. Using suitable regulators it is also possible to introduce groups containing silicon into the copolymer, by means, for example, of mercaptoalkyltrialkoxysilanes such as mercaptopropyltrimethoxysilane.
The emulsion polymerization can be conducted either continuously or batchwise, preferably by a semicontinuous procedure. In this case the monomers to be polymerized can be supplied continuously, including by a stepwise or gradient regime, to the polymerization batch. The monomers can be supplied to the polymerization either as a monomer mixture or else as an aqueous monomer emulsion.
Besides the seed-free preparation procedure, a defined polymer particle size can also be established by conducting the emulsion polymerization in accordance with the seed latex technique or in the presence of seed latex prepared in situ. Techniques of this kind are known and can be found in the prior art (see EP-B 40419 and Encyclopedia of Polymer Science and Technology, Vol. 5, John Wiley and Sons Inc., New York 1966, p. 847).
The pressure and temperature of polymerization are of minor importance. Polymerization is generally conducted at between room temperature and 120xc2x0 C., preferably at from 40 to 110xc2x0 C., and with particular preference at from 50 to 100xc2x0 C.
Following the actual polymerization reaction it may be necessary to substantially free the aqueous polymer dispersions of the invention from odoriferous substances, such as residual monomers and other volatile organic constituents. This can be done, conventionally, by physical means, through distillative removal (especially by steam distillation) or by stripping with an inert gas. A reduction in the amount of residual monomers can also be achieved chemically, by free-radical postpolymerization, especially under the action of redox initiator systems, as are set out, for example, in DE-A 44 35 423, DE-A 44 19 518 and DE-A 44 35 422. Postpolymerization is preferably conducted with a redox initiator system comprising at least one organic peroxide and an organic sulfite.
In this way it is possible to obtain polymer dispersions with polymer contents of up to 80% by weight, based on the overall weight of the dispersion. For preparing the formulations employed in accordance with the invention it is preferred on practical grounds to employ dispersions having polymer contents in the range from 30 to 70% by weight, in particular from 40 to 65% by weight.
The formulations that are employed in accordance with the invention can in principle take any desired formxe2x80x94in other words, solvent-containing or solvent-free. The dispersion medium used preferably comprises water or mixtures of water with a water-miscible organic solvent, such as a C1-C4-alkanol, for instance methanol, ethanol, n- or iso-propanol, n-, iso-, 2- or tert-butanol, glycol, propylene glycol, butylene glycol, glycerol, diethylene glycol, triethylene glycol, tetrahydrofuran or the like.
The formulations used in accordance with the invention preferably include not more than 50% by weight, in particular not more than 20% by weight and specifically not more than 10% by weight, based on the overall weight of the formulation, of water-miscible solvents. With very particular preference, the formulations of the invention, in addition to water, contain no organic solvents other than customary antifreeze agents and film-forming auxiliaries.
In addition, the aqueous formulations, insofar as the copolymers P have been prepared by free-radical aqueous emulsion polymerization, also include the surface-active substances employed for this purpose, such as emulsifiers and/or protective colloids.
The solutions and dispersions of the copolymers P can be used as they are in accordance with the invention. However, the formulations generally include from 0.1 to 30% by weight of customary auxiliaries. Preferably, based on their overall weight, the formulations used in accordance with the invention contain
i. from 10 to 60% by weight of at least one copolymer P and
ii. from 0.1 to 20% by weight of customary auxiliaries.
Examples of customary auxiliaries are wetting agents, fungicides, defoamers, thickeners, antifreezes, leveling assistants, plasticizers and film-forming auxiliaries. Examples of suitable film-forming auxiliaries are ethylene, propylene, butylene, hexylene, diethylene, dipropylene and dibutylene glycol, their monoethers with C1-C4-alkanols, such as diethylene glycol monoethyl or monobutyl ether, propylene glycol monophenyl, monopropyl or monobutyl ether, dipropylene glycol monopropyl or monobutyl ether, their ether acetates, such as diethylene glycol monoethyl and monobutyl ether acetate, propylene glycol monopropyl and monobutyl ether acetate, dipropylene glycol n-butyl ether acetate, and also alkyl esters of aliphatic mono- and dicarboxylic acids, such as Texanol(copyright) from Eastman Kodak, or technical-grade mixtures thereof, such as Lusolvan FBH from BASF AG (di-n-butyl ester mixtures of succinic, glutaric and adipic acid). Suitable plasticizers are all those customary for aqueous dispersions, examples being (oligo)propylene glycol alkyl phenyl ethers as are obtainable, for instance, as Plastilit(copyright) 3060 from BASF AG.
In addition, the aqueous formulations employed in accordance with the invention may also include inorganic fillers and/or pigments. In that case the formulations used in accordance with the invention, based on their overall weight, preferably contain
i. from 10 to 60% by weight of at least one polymer P,
ii. from 0.1 to 20% by weight of customary auxiliaries, and
iii. from 10 to 60% by weight of at least one finely divided filler and/or one inorganic pigment.
Examples of typical pigments are titanium dioxide, preferably in the rutile form, barium sulfate, zinc oxide or lithopones (zinc sulfide+barium sulfate). For decorative purposes the formulations may also include colored pigments, examples being iron oxides, carbon black or graphite. Suitable fillers include alumosilicates, such as feldspars, silicates, such as kaolin, talc, mica, magnesite, alkaline earth metal carbonates, such as calcium carbonate in the form, for example, of calcite or chalk, magnesium carbonate, dolomite, alkaline earth metal sulfates, such as calcium sulfate, and silica, etc.
In one preferred embodiment of the present invention the aqueous formulations are employed in the form of a clearcoat. In this case they generally include, based on their overall weight, from 10 to 60% by weight, preferably from 40 to 55% by weight of at least one copolymer P and from 0.1 to 20% by weight, preferably from 0.5 to 10% by weight, of customary auxiliaries, especially defoamers and/or film-forming auxiliaries. In particular, these aqueous formulations advantageously include a copolymer P having a glass transition temperature Tg in the range from +20 to +50xc2x0 C., preferably from +30 to +45xc2x0 C., and have a crosslinking monomer (monomers c)) content, preferably comprising allyl methacrylate, in the range from 0.5 to 2.0% by weight, preferably in the range from 0.75 to 1.5% by weight.
In another embodiment of the present invention the aqueous formulations are employed in the form of pigmented and/or filled formulations. In this case the total content of copolymer P in the aqueous formulation is within the range from 10 to 60% by weight, preferably in the range from 20 to 40% by weight, the content of auxiliaries is within the range from 0.1 to 20% by weight and preferably within the range from 0.5 to 10% by weight, and the content of fillers and/or pigments is in the range from 10 to 60% by weight and, in particular, from 15 to 40% by weight. The amount of pigments and/or fillers is generally between 50 and 450 parts by weight per 100 parts by weight of copolymer P in the aqueous formulation. Pigment-containing formulations will also, preferably, include a dispersant and/or wetting agent in addition to the film-forming auxiliaries and defoamers. In particular, these pigmented and/or filled aqueous formulations advantageously include a copolymer P having a glass transition temperature Tg in the range from +0 to +30xc2x0 C., preferably from +5 to +25xc2x0 C., and have a crosslinking monomer (monomers c)) content, preferably comprising allyl methacrylate, in the range from 0.05 to 0.2% by weight, preferably in the range from 0.075 to 0.15% by weight.
The present invention also relates to a method of coating shaped mineral articles which comprises applying at least one aqueous, film-forming formulation as described herein to the shaped mineral article. In general the amount of aqueous formulation to be applied (calculated in its wet form) will be from 100 to 700 g/m2, corresponding to a dry add-on of from 50 to 400 g/m2 and, in particular, to a dry add-on of from 100 to 300 g/m2. Application can take place in a manner known per se by spraying, troweling, knife coating, rolling or pouring. The drying which generally follows can be carried out either at room temperature or at an elevated temperature in the range, for example, of from 40 to 120xc2x0 C.
In one customary embodiment of the method of the invention, the shaped mineral article is provided with at least two coatings. To do this, in a first step a first aqueous film-forming formulation 1 is applied to the as yet untreated shaped mineral article, and is dried if desired, and then in a second step a further aqueous film-forming formulation 2 is applied to the shaped article provided with the first coating. Both the first and second steps can be repeated, so that in this way it is possible to obtain coatings having three or more layers.
The present invention additionally provides a method of coating shaped mineral articles in which an untreated shaped mineral article is provided with at least one first coating by applying to said shaped mineral article at least one first aqueous film-forming formulation (formulation 1) which comprises at least one copolymer P or copolymer Pxe2x80x2 composed of ethylenically unsaturated monomers, having a glass transition temperature in the range from xe2x88x9220 to +80xc2x0 C., in dispersed form and then drying said article, repeating this procedure if desired, and subsequently applying at least one further aqueous film-forming formulation (formulation 2) comprising at least one copolymer P as described above, as topcoat, to the shaped mineral article provided with at least one first coat.
With particular preference, the film-forming component of the aqueous formulation 2 applied as topcoat is the above-defined copolymer P, preferably in the above-described embodiment for clearcoats. In contrast, the film-forming component of the first aqueous formulation 1 can be selected from the copolymers P, preferably in the above-described embodiment for pigmented and/or filled formulations, and from different polymers Pxe2x80x2. The latter are generally likewise composed of ethylenically unsaturated monomers and are present in dispersed form in the first aqueous formulation. In accordance with the invention the polymer Pxe2x80x2, similarly to the copolymer P, will have a glass transition temperature in the range from xe2x88x9220 to +80xc2x0 C. In one preferred embodiment of the present invention the film-forming component of the aqueous formulation 1 is a polymer Pxe2x80x2 which is different from the copolymer P.
Suitable polymers Pxe2x80x2 are all those polymers which are commonly present in aqueous formulations with a coating of shaped mineral articles. Typical polymers Pxe2x80x2 and corresponding aqueous, film-forming formulations which are suitable for the initial coating of shaped mineral articles are described, for example, in EP-A 469 295 and DE-A 195 14 266. The disclosure content of these documents is hereby fully incorporated by reference.
The constituent monomers of the polymer Pxe2x80x2 are normally selected predominantly from the abovementioned monomers a) and b), it being possible for the polymer Pxe2x80x2 to contain up to 30% by weight of monomers other than the monomers a), b) and c), in copolymerized form. In many cases, the key difference between the polymers Pxe2x80x2 and the copolymers P is that the former contain no crosslinking monomers c).
In general, from 65 to 99.9% by weight of the constituent monomers of the polymer Pxe2x80x2 are selected from vinylaromatic monomers, especially styrene and xcex1-methylstyrene, the abovementioned esters of acrylic acid with C1-C12-alkanols, the abovementioned esters of methacrylic acid with C1-C8-alkanols, and the vinyl esters of aliphatic monocarboxylic acids, it being possible for up to 70% by weight of the monomers to be selected from the esters of methacrylic acid with C1-C4-alkanols, and/or at least 50% by weight are methyl methacrylate. Furthermore, the constituent monomers of the polymer Pxe2x80x2 generally comprise from 0.1 to 30% by weight, preferably from 0.2 to 20% by weight, and in particular from 0.5 to 5% by weight, of monomers different from these.
The polymers Pxe2x80x2 can be prepared by the methods described for the copolymers P, with preparation by means of free-radical aqueous emulsion polymerization being preferred for the polymers Pxe2x80x2 as well.
Following their preparation, the aqueous dispersions of the polymers Pxe2x80x2 and of the copolymers P are neutralized by addition of a base, such as ammonia, amines of low volatility, alkali metal hydroxides or alkaline earth metal hydroxides, or alkaline earth metal oxides. Following neutralization, the pH of the dispersions is preferably in the range from 6 to 9. It is preferred to carry out neutralization with ammonia or with alkali metal hydroxides, especially sodium hydroxide. In the case of neutralization with sodium hydroxide it has been found advantageous for the pH after neutralization to be within the range from 7.0 to 7.9. It has been found particularly advantageous if a pH of 7.9 is not exceeded during or after the addition of the alkali metal hydroxide.
In one preferred embodiment of the present invention the aqueous film-forming formulation 1 comprises, in addition to the film-forming component and the customary auxiliaries, at least one finely divided filler and/or one inorganic pigment. The amount of copolymer P and/or polymer Pxe2x80x2 in the formulation 1, based on its overall weight, is in the range from 10 to 60% by weight, preferably in the range from 20 to 40% by weight. The auxiliaries content is generally in the range from 0.1 to 20% by weight, and preferably, in the range from 0.5 to 10% by weight, and the amount of fillers and/or pigments is within the range from 10 to 60% by weight, and in particular from 15 to 50% by weight. The amount of pigments and/or fillers is generally between 50 and 450 parts by weight per 100 parts by weight of copolymer P and/or polymer Pxe2x80x2 in the aqueous formulation 1. Furthermore, in addition to the film-forming auxiliaries and the defoamers, pigmented formulations will preferably include a dispersant and/or wetting agent.
In this preferred embodiment the pigment content of the aqueous formulation 2 can be the same as the pigment content of the aqueous formulation 1. Preferably, however, it is much lower; in other words, the difference in pigment concentration is at least 10% by weight. The pigment concentration of the second formulation is in particular xe2x89xa620% by weight based on the overall weight of the formulation 2. The formulation 2 can also be used free of pigments. In this way, particularly glossy coatings are obtained.
Accordingly, the present invention additionally provides a method wherein the first aqueous film-forming formulation (formulation 1), based on its overall weight, comprises
i. from 10 to 60% by weight of at least one polymer Pxe2x80x2
ii. from 0.1 to 20% by weight of customary auxiliaries, and
iii. from 10 to 60% by weight of at least one finely divided filler and/or one inorganic pigment,
and the second aqueous film-forming formulation (formulation 2), based on its overall weight, comprises
i. from 10 to 60% by weight of at least one polymer P,
ii. from 0.1 to 20% by weight of customary auxiliaries, and
iii. an overall level of pigment/filler which is lower by at least 10% by weight than that of the first formulation.
In this embodiment, the formulation 1 will normally be applied in an amount from 70 to 300 g/m2 (calculated on a wet basis) and the formulation 2 in an amount of from 30 to 150 g/m2 to the shaped mineral article. The weight ratio of the amount of formulation 1 applied to the amount of formulation 2 applied will customarily be within the range from 4:1 to 1:1.5 and, in particular, in the range from 3:1 to 1.2:1.
The method of the invention can be applied in principle to all shaped articles comprising a mineral binder. It develops its preferential effects when applied to shaped mineral articles comprising cement as their binder (precast concrete products and fiber-reinforced cement slabs). By precast concrete products are meant shaped structures made of concrete and/or gas concrete, such as slabs, pipes and/or roof tiles. The precast concrete product is produced conventionally from ready-mixed concrete by an extrusion process. The aqueous formulations of the invention have the advantage here that they can be applied not only to a precast concrete product which has already set but also to the freshly produced and not yet set xe2x80x9cgreenxe2x80x9d product.
Drying of the green precast concrete products coated in accordance with the invention can be carried out conventionally, either at room temperature or elevated temperature. The coated green precast concrete product is preferably introduced into what is known as a chamber, where it is set in a process lasting from about 6 to 24 hours at from 40 to 70xc2x0 C. and during which the copolymer of the coating composition forms a film. Following this process, the product is preferably sprayed a second time with the aqueous formulation of the invention. A second drying operation takes place in a tunnel furnace at temperatures of the circulating air of around 100xc2x0 C.
Shaped mineral articles which have already set can also be coated at customary ambient temperatures, such as room temperature, with the formulations of the invention.
The advantageous properties of the aqueous formulations of the invention also apply in the case of shaped mineral articles that have been coated with a cement slurry. Such a slurry generally encompasses the customary pigments, a cement as mineral binder, customary auxiliaries and water in an appropriate amount, and is applied to the shaped mineral article, preferably a precast concrete product, which has not yet finally set. After setting, the cement slurry coat has a thickness in the range from 200 to 2000 xcexcm. The aqueous formulations of the invention can be applied in the same way as described above.
The aqueous formulations of the invention prove to be equally advantageous when applied to fiber-reinforced concrete slabs; that is, flat, shaped mineral articles which comprise cement as binder and also mineral or organic fibers, such as polyester and/or polyamide fibers, as aggregates. The application of the aqueous formulations of the invention generally takes place as described for green precast concrete products.
The shaped mineral articles coated in accordance with the invention are notable firstly for the fact that their coating exhibits a considerably higher long-term stability on outdoor weathering. In particular, there is virtually no reduction in the gloss of the coating even after years of weathering. The adhesion of the coating to the shaped mineral articles is high both in the fresh state and after weathering. Further still, the shaped coated articles are effectively protected against efflorescence. This property is particularly significant for concrete roof tiles, which therefore constitute a preferred embodiment of the invention. In addition to this, the coatings are resistant to blocking.
Use of the aqueous formulations of the invention leads accordingly to enhanced preservation of the surface of shaped mineral articles with increased gloss stability and high long-term durability. The shaped mineral articles thus coated are novel and are likewise provided by the present invention.

Aqueous, film forming preparations for coating mineral shaped bodies

Abstract: a) from 80 to 99.89% by weight of at least one monomer selected from esters of acrylic acid with C1-C12-alkanols, esters of methacrylic acid with C1-C8-alkanols, and monovinylaromatics,

Abstract: b) from 0.1 to 19.99% by weight of at least one monomer different from a), and

Abstract: c) from 0.01 to 1.9% by weight of at least one crosslinking monomer selected from esters of acrylic or methacrylic acid with linear or branched C3-C6-alkenols, cyclic C5-C7-alkenols and polycyclic C2-C12-alkenols.


A polyurethane composition comprising:. a) an isocyanate-terminated polyurethane prepolymer; and PA1 b) a curative agent comprising i) a polyol; ii) an aromatic diamine; iii) a thixotropic aliphatic amine; and iv) a thixotropic colloidal additive. This composition is useful for coating cylindrical objects.

A variety of elastomeric coverings can be used to coat rolls in applications in which the rolls require protection. Polyurethane elastomers are used as roll coatings in applications where abrasion and tear resistance, good load bearings characteristics, high hardness, and solvent resistance are required.
In steel mill applications, for example, large numbers of these rolls are used for guiding, tensioning, and otherwise engaging steel strip during rolling and pickling applications. The rolls are subjected to the strong chemical agents used for pickling and cleaning the strip. Similarly, in paper mills, polyurethane-coated metal rolls are used for supporting and conveying paper through high pressure nips of paper making machine assemblies such as press rolls, calendar stacks, and the like. The rolls used in paper mill operations require a protective cover whose thickness can be varied depending on the roll's anticipated use. Being able to control the thickness of the protective cover is, therefore, desirable.
Different methods have been developed for applying coatings to metal rolls. U.S. Pat. Nos. 3,520,747; 3,646,651; and 4,368,568 describe multistep methods for multilayer coating of rolls.
U.S. Pat. No. 4,571,798 describes a method wherein paper mill rolls are coated by spraying a quick-gelling polyurethane onto a core.
Ruprecht et al, Polyurethanes World Congress 1991 (Sep. 24-26, 1991), 478-481, describe rotational casting techniques useful for producing roll coverings using fast-reacting polyurethane elastomer systems. In these systems, the polyurethane reaction mixture is metered through a movable mixing head which travels at constant speed in the axial direction along the rotating roll core, a short distance above its surface. The polyurethane reaction mixture solidifies very quickly, in a matter of seconds, to produce a polyurethane coating with a thickness buildup of 4-5 mm. Additional layers of the polyurethane reaction mixture are applied until the desired thickness of polyurethane coating is achieved.
Rotational casting reduces the number of steps involved in roll coating. However, if the polyurethane reaction mixture gels too slowly, the polyurethane coating will drip off the roll. If the polyurethane reaction mixture is formulated to gel quicker, the polyurethane can gel in the head of the mixer or ridges can develop on the outer surface of the roll requiring machine finishing of the polyurethane coating on the surface of the roll.
Thickening agents, such as fumed silica, can be added to the polyurethane reaction mixture in a rotational casting procedure, to thicken the coating and eliminate dripping. However, the use of thickening agents alone can often result in the polyurethane reaction mixture becoming too thick to flow or in the polyurethane coating being applied in undesirable thicknesses.
It is therefore an object of the present invention to provide a new polyurethane composition useful for coating cylindrical objects. It is a further object of this invention to provide a polyurethane compostion which can be used in a rotational casting process.

Polyurethane composition useful for coating cylindrical parts


A jewelry suspension harness includes a piece of jewelry or stone having opposed front and back surfaces integral with a top edge and opposed side edges wherein the top edge has a top notch at about a midpoint between the side edges and the side edges have side notches substantially opposite one another. A suspension wire having opposed ends is provided with a loop that is nestled within the top notch wherein the suspension wire is placed adjacent the front and back surfaces and provided in a substantially parallel relationship with the side edges and wherein the suspension wire is coupled to the side notches to carry the piece of jewelry.

It is well known that jewelry in the form of precious stones, such as diamonds, rubies and the like or in the form of semi-precious stones, metal or glass and the like may be mounted to rings, necklaces or earrings. Some stones may be mounted in various ways such as by glueing or cementing the stone to a setting or mount so as to predominantly display the stone without attracting attention to the mount. In some instances, it is known to carry or support these stones with barrels that engage undercuts provided in the stone. This allows numerous stones to be set in a necklace, broach or the like without detracting from the appearance of the jewelry.
However, none of the aforementioned methods for setting the jewelry adequately provide structure or methodology for suspending jewelry. Although it is known to glue or cement the top portion of a stone to a mounting and then suspend the stone from the mounting, it has been found that this method is inadequate. In particular, the cement or glue tends to degrade after a period of use, causing the stone to release from the mounting, which in turn causes embarrassment to the unsuspecting wearer of the jewelry. Although the stone can be reattached to the mounting, it will be appreciated that some stones are lost and that the user or wearer may not wish to repair the jewelry due to the inconvenience.


A rotary pallet device for delivering a pallet to an automated machine, such as a CNC vertical machining center. A pallet is mounted to a retractable slide. The retractable slide is movably mounted with respect to a rotatable platform. An operator or worker accesses one or more stations, each with a rotatable door that at least partially houses a receiver for a pallet and/or a workpiece.

1. Field of the Invention
This invention relates to an advanced rotary pallet pool that can, for example, provide synchronized delivery of multiple pallets to various types of automated machines, such as a CNC Vertical Machining Center.
2. Discussion of Related Art
Conventional automated machines use pallets to secure and/or otherwise mount workpieces. The known automated machines modify the workpieces over a given time period, often without requiring an operator's attention.
Conventional automated machines are able to handle multiple pallets. Known safety doors slide or otherwise move in an upward and/or a downward direction.


Object serialization is used to communicate references regarding shim objects. Shim objects are instantiated on one or more ranks of a distributed software application. The shim objects store a registration object in a distributed object cache for each rank. The registration object includes a unique identifier for a distributed array object and a reference to a local portion of the distributed array. The shim objects are serialized for communication of the stored references from a master rank of the distributed application to one or more worker ranks of the distributed application. Upon serializing the shim objects, the shim object's stored references are communicated from the distributed object cache for that rank to the one or more worker ranks of the distributed application. The shim objects are subsequently removed so that references to the underlying distributed array object are also removed, and memory previously allocated to the unique identifier is recoverable.

Computers have become highly integrated in the workforce, in the home, in mobile devices, and many other places. Computers can process massive amounts of information quickly and efficiently. Software applications designed to run on computer systems allow users to perform a wide variety of functions including business applications, schoolwork, entertainment and more. Software applications are often designed to perform specific tasks, such as word processor applications for drafting documents, or email programs for sending, receiving and organizing email.
Software applications may be configured for use on a single, local computer system, or they may be configured for distribution over multiple different computer systems. Such applications are referred to as "distributed applications". These applications may be divided into different portions, and each portion may be executed in parallel with the other portions. Similarly, applications may be configured to process local data arrays or distributed data arrays. Distributed data arrays may be stored on and/or processed over multiple different databases. Performing operations that are consistently applied across the distributed data arrays, however, may be problematic.

Providing distributed array containers for programming objects


An optical fiber amplifier suited for use in optical fiber transmission systems includes a plurality of optical passive components. The optical passive components are integrated into an assembly including a birefringent crystal, a first lens, a magneto-optic crystal, an optical filter, and a second lens, all of which are axially aligned in this order, with a half-wave plate interposed between the birefringent crystal and the first lens. The birefringent crystal is opposed to end faces of first and second optical fibers and separates incident light into two linearly polarized light beams having respective polarized light planes generally perpendicular to each other. The half-wave plate allows light emitted from the second optical fiber to pass therethrough and rotates a polarized light plane of incident light. The first lens converts incident light into a generally collimated ray, and the magneto-optic crystal rotates a polarized light plane of incident light by an angle of .pi./8+Nn/4 (N=0, 1, 2, . . .) under the influence of a magnetic field. The optical filter reflects light having a specific wavelength and allows light having a wavelength other than this specific wavelength to pass therethrough, and the second lens are opposed to end faces of third and fourth optical fibers and converges a collimated ray introduced thereinto. By this construction, an optical coupling system is constituted between the first and second optical fibers and between the third and fourth optical fibers and one of the first and second optical fibers.

1. Field of the Invention
The present invention relates generally to an optical fiber amplifier for use in optical fiber transmission systems, and more particularly to an optical passive component assembly constituting part of the optical fiber amplifier.
2. Description of the Prior Art
In optical fiber transmission systems, an optical fiber amplifier employing an erbium-doped optical fiber or fibers has widely been used wherein a plurality of optical passive components such as, for example, a polarized light coupler, an optical wavelength coupler (multiplexer), and a polarization-independent optical isolator are integrated. The polarized light coupler polarizes and couples two laser beams each having a wavelength of 1.48 .mu.m and emitted from two optically pumping laser diodes (semiconductor lasers), respectively, to obtain a doubled optical output. The optical wavelength coupler makes pumping light enter the erbium-doped optical fiber and takes out light having a wavelength of 1.55 .mu.m amplified by the erbium-doped optical fiber using an optical fiber. The polarization-independent optical isolator allows signal light to pass therethrough only in one direction, thereby preventing the amplified light from traveling in the reverse direction and entering the erbium-doped optical fiber again.
Each of these optical passive components generally includes at least two opposed lenses, two optical fibers disposed on opposite sides of the two opposed lenses, and various optical elements interposed therebetween. In applications where a plurality of optical passive components are integrated in an optical fiber amplifier, because the optical fiber amplifier requires a number of lenses, the size thereof becomes large and the manufacturing cost thereof becomes high. Furthermore, because optical fibers of one component are fused and connected to those of another, not only the optical loss is increased due to such connection, but also a variation in optical loss occurs. In addition, because each of conventional optical fiber amplifiers generally require space to fasten a number of optical passive components and space to place the mutually connected optical fibers, the amplifier body tends to become bulky.

Matsushita Electric Industrial Co., Ltd.