A composition comprising coloring substance bodies that are at least partially coated with beet pectin, chicory pectin and/or Jerusalem artichoke pectin or other pectin types having a high degree of acetylation. The composition which may be water dispersible is useful for preparation of health improving products and/or coloring products for use in the coloring of edible products including food products and nutraceuticals, and for coloring of pharmaceutical products.

The present invention relates in its broadest aspect to the field of manufacturing food products and pharmaceutical products and specifically there is provided a novel colouring substance composition, which is useful for colouring such products.
Colouring agents containing natural or synthetic colouring substances are commonly used as additives in the manufacturing of food products and pharmaceutical products. A wide range of such colouring agents are commercially available making it possible for the manufacturer, where a particular colour tone is desired, to select a single colouring agent having the desired colour or a mixture of colouring agents, which in an appropriate combination impart the desired colour to the product. Or alternatively, the manufacturer may with to use an agent which, in addition to its colouring effect, has a health improving effect and hence select such a single health improving agent or a mixture of such agents.
The commercially available colouring agents can contain synthetic substances including substances that are also normally referred to as dyes or azodyes, or such agents can contain pigments or other colouring substances of natural origin, e.g. in the form of plant material containing a colouring substance, or as more or less purified colouring substances separated from plant, animal or microbial materials naturally containing such substances.
Occasionally, food grade or pharmaceutically acceptable colouring agents are provided that contain colouring substances in the form of synthetic or artificial compounds having substantially the same chemical composition as natural occurring colouring substances. This type of colouring agents are also referred to in the art as xe2x80x9cnatural identicalxe2x80x9d colours. However, in the present context, the expression xe2x80x9cnaturally occurring colouring agentsxe2x80x9d is used to designate pigments or other colouring substances which are derived from a natural source.
Any of the above types of available colouring agents including agents comprising food grade or pharmaceutically acceptable natural colouring substances can be hydrophilic or hydrophobic and thus, water soluble, sparingly soluble in water and aqueous media or essentially water-insoluble. A hydrophilic, water soluble colouring material as such can therefore only be used for colouring a product having an aqueous phase during and/or after manufacturing. Similarly, the use of a hydrophobic and/or water insoluble colouring material or substance as such requires that the product to be coloured has a hydrophobic or lipid phase in which the colouring substance is soluble. Certain colouring substances such as curcumin are substantially insoluble in water at neutral pH or below, but are soluble in alkaline aqueous media.
However, it may be desirable to obtain the colour tone of a particular colouring substance that is insoluble or sparingly soluble in an aqueous phase or a mixture of such substances in a food product or a pharmaceutical product that does not comprise a phase in which the colouring substance is sufficiently soluble to provide the desired colouring. There is therefore a continuous industrial need for colouring agents containing colouring substances that are water insoluble or sparingly insoluble in water, which are in the form of water-miscible or water dispersible compositions having a high colouring efficiency.
WO 91/06292 discloses a process of preparing a water dispersible composition comprising a hydrophobic/aerophilic solid pigment that is prepared by milling the pigment in an aqueous medium in the presence of a hydrocolloid, in particular gelatine, gum arabic, soybean protein and/or modified starch. Similar methods are disclosed in WO 97/26802 and WO 97/26803 where gelatine is used as the hydrocolloid. However, none of these disclosures refer to the use of beet pectin or other pectins of a similar type such as chicory pectin or Jerusalem artichoke pectin as a wetting agent and/or suspending agent in the manufacturing of compositions of water-insoluble or sparingly soluble colouring substances, including such compositions that are water dispersible.
It has now been found that compositions of colouring substances that are hydrophobic, water-insoluble and/or sparingly insoluble in water and which have a high colouring efficiency or other desired properties in food products and pharmaceutical products can be provided by using beet pectin, chicory pectin and/or Jerusalem artichoke pectin as a wetting and/or dispersing agent. It was surprisingly found that compositions comprising such pectins have a significantly superior colouring effect when comparing with other hydrocolloids or other pectin types such as the commonly used citrus pectin types.
A conventionally preferred hydrocolloid in the manufacturing of water dispersible compositions of hydrophobic solids is gelatine. However, being of animal origin with the associated risk that it may carry pathogenic or toxic substances and the fact that most gelatine types are not xe2x80x9ckosherxe2x80x9d grade implies that the incorporation of gelatine into food products, at least for some consumers, may be objectionable. It is therefore one significant objective of the present invention to provide the means for manufacturing coloured or pigmented food products and pharmaceutical products that do not imply that any such objections can be raised and at the same time provide water-dispersible colouring substance compositions having a high colouring efficiency.
Accordingly, the present invention provides in a first aspect a composition comprising bodies of a colouring substance that are at least partially coated with a pectin selected from beet pectin, chicory pectin and Jerusalem artichoke pectin. In useful embodiments, the colouring substance is a solid pigment that, at least under certain conditions, is insoluble or sparingly soluble in water.
In a further aspect the invention pertains to a method of producing a colouring substance composition as defined above, said method comprising preparing a dispersion of the colouring substance by comminuting said pigment in an aqueous phase comprising beet pectin, chicory pectin and/or Jerusalem artichoke pectin in an amount of at least 1% of the colouring substance to obtain a dispersion containing the colouring substance in the form of bodies of the colouring substance that are at least partially coated with the pectins. In accordance with the invention it may be preferred that the colouring substance bodies obtained have an average largest dimension of at the most 10 xcexcm such as the most 5 xcexcm including an average largest dimension of at the most 1 xcexcm.
In still further aspects, the invention relates to the use of the composition of the invention in the manufacturing of an edible product, the use of the composition in the manufacturing of a pharmaceutical or nutriceutical product, a pharmaceutical or nutraceutical product comprising the composition according to the invention and edible products comprising such composition.
In yet other aspects of the present invention colouring compositions are provided which comprise chlorophylin (30 ppm), turmeric (30 ppm) or bixin (20 ppm) which compositions, when tested in a soft drink system containing sucrose, 430.0 g; Na-benzoate, 0.7 g; K-sorbate, 0.9 g; Ascorbic acid, 0.1 g; Citric acid mono-hydrate, 8.6 g and demineralised water to 5 liter, results in a chroma value of at least 33, 30 and 25, respectively when measured with a Minolta Tristimulus CT 310 apparatus.
The colouring substance composition according to the invention comprises colouring substance bodies that are at least partially coated or encapsulated with beet pectin, chicory pectin and/or Jerusalem artichoke pectin. In preferred embodiments the colouring substance is water-insoluble or sparingly insoluble in water and aqueous media. Several of such substances are hydrophobic and/or aerophilic, implying that they are not readily wetted when contacted with an aqueous medium that does not contain a suitable wetting agent. As used herein, the expressions xe2x80x9csparingly soluble in waterxe2x80x9d, xe2x80x9cwater-insolublexe2x80x9d or xe2x80x9chydrophobicxe2x80x9d are used to indicate that the colouring substance will occur as a separate phase in aqueous media and/or has such a high degree of hydrophobicity that it cannot be dispersed or suspended in water without the application of high shear stress and/or the addition of surface active substances such as emulsifying agents or tensides.
Certain colouring substances that are water-insoluble or sparingly soluble in water may have a low degree of hydrophobicity or even be hydrophilic. Such substances are also encompassed by the invention. In the present context, the expression xe2x80x9cwater-insoluble (or sparingly soluble in water) and hydrophilicxe2x80x9d indicates that the colouring substance in the amounts used herein is water-insoluble or sparingly soluble in aqueous media at described above. Accordingly, colouring substances of a group, which is generally referred to as hydrophilic, are actually insoluble or sparingly soluble in aqueous media at about neutral pH or below, or at pH values up till about 9. Several food products have an aqueous phase with a pH below 7 and this acidic environment will in many cases render a colouring substance as such unstable and the substance will tend to precipitate resulting in a change of the colour hue. This is e.g. observed in products such as acidified milk products. The compositions of the present invention where the colouring substances are covered by pectin are thus useful for such acidic food products.
The present invention is based on the finding that certain pectin substances including pectin derived from sugar beet, Beta vulgaris, chicory pectin and Jerusalem artichoke pectin are highly effective as wetting and/or dispersing agents in the preparation of a composition of the invention. Pectin is a naturally occurring polysaccharide, essentially made up of regions containing polygalacturonic acid chains and regions containing chains which consist alternately of rhamnose units and galacturonic acid units with side chains mainly containing arabinose and galactose units. The acid groups of the galacturonic acid units are partially esterified with methanol and some of the hydroxyl groups thereof may be acetylated. In contrast to e.g. citrus pectin and apple pectin, beet pectin, chicory pectin and Jerusalem artichoke pectin have a relatively high degree of acetylation. It is hypothesised that at least one factor determining the high wetting and/or dispersing efficiency of these pectins is their relatively high content of acetyl groups. The presence of hydrophobic groups is known to give the molecule a surface-active character which will enhance the emulsifying properties of a compound. Acetyl groups may enhance the hydrophobic nature of the pectin, thereby decreasing surface tension and increasing dispersability. It is therefore assumed that other pectin species having a high degree of acetylation such as pectin derived from chicory or Jerusalem artichoke will have similar useful effects e.g. in the manufacturing of a composition according to the invention. The use of pectins having a relatively high degree of acetylation (DA), such as a DA in the range of at least 10-60%, including a DA in the range of 20-50% e.g. a DA in the range of 30-40%, is also encompassed by the invention. It is further contemplated that pectins having a DA of at least 10%, 20%, 30%, 40%, 50% or 60%, is useful in order to obtain compositions having the characteristics of the present invention.
Acetylation may be obtained by chemically altering the degree of acetylation in natural as well as artificial pectins.
In accordance with the invention, the pectin is suitably used in an amount which is in the range of 1-90 wt % of the colouring substance, such as in the range of 2-80 wt %. In preferred embodiments, the amount of the pectin hydrocolloid is in the range of 3-60 wt % such as in the range of 5-50 wt % and the amount of pectin can e.g. be less than 10 wt % of the colouring substance or at least 10 wt % of the colouring substance. In still other embodiments, the amount of pectin is at least 10 wt %, such as at least 20 wt % of the combined amounts of the pectin and at least one further hydrocolloid, if such a further hydrocolloid is present.
In other useful embodiments, the amount of pectin is more than 100 wt % of the pigment, i.e. the ratio between colouring substance and hydrocolloid can be in the range of 1:1 to 1:10,000 such as in the range of 1:10 to 1:5,000 or in the range of 1:100 to 1:1,000. The amount of pectin may also be calculated on the composition. Thus the amount of pectin is preferably in the range of 1-50 wt % of the composition, such as in the range of 1-10 wt %, e.g. 1.5, 2 or 2.5 wt %.
The colouring substance can be any food grade or pharmaceutically acceptable hydrophobic or hydrophilic colouring matter that, at least under certain conditions, is water insoluble or sparingly soluble in water as defined above, and which belongs to any of the above-mentioned types including synthetic colouring substances, natural colouring substances derived from a natural source and xe2x80x9cnature identicalxe2x80x9d colouring substances. When the colouring substance is a natural color as defined herein, it may be in a substantially pure form or it may be contained in the material where it occurs naturally such as a plant, animal or microbial material, optionally in combination with a food grade and/or pharmaceutically acceptable carrier. The presently most commonly used water-insoluble or sparingly soluble natural colouring substances that are useful in the composition according to the invention include carotenoids, curcumin, carmine, porphyrin pigments including chlorophyll, and vegetable carbon black. It will be appreciated that the composition according to the invention may comprise a single colouring substance or it may contain two or more different colouring substances.
Carotenoids which have yellow, orange or red colours occur widely in nature and important sources include plants including grass species, the annatto tree, citrus species, Capsicum annum, Crocus sativus flowers and marigold flowers, marine algae, yeast species and some animals. Carotenoids can be divided into the following classes: carotenoid hydrocarbons, xanthophylls and apocarotenoids. Typical examples of carotenoids include bixin, norbixin, xcex2-carotene, apocarotenals, canthaxanthin, saffron, crocin, capsanthin and capsorbuin occurring in paprika oleoresin, lutein, astaxanthin, rubixanthin, violaxanthin, rhodoxanthin, lycopene and derivatives hereof.
Further water-insoluble and/or hydrophobic colouring substances that are useful in the present invention include curcumin which is the major pigment in turmeric, the coloured oleoresin extract of the Curcuma root, vegetable carbon black, which is produced by fully carbonising vegetable material and grinding it to a fine powder, and the porphyrine pigments such as oil-soluble chlorophylls based substantially on phaeophytin a or b and epimers and isomers thereof.
In the present context, a further important class of natural colouring substances is quininoid pigments of which the most commonly used is cochineal carmine that is obtained by aqueous extraction from the insect Coccus cacti. Normally, the extract is precipitated as the insoluble aluminium lake known as cochineal carmine which is soluble in alkaline aqueous media but is sparingly soluble in aqueous media having a pH below about 9.
A still further useful class of natural colouring substances is the polyphenols, which are extracted from grape seeds and which are characterised as having a desired colour but also an off-flavour. In order to reduce or eliminate this off-flavour it is convenient to encapsulate the substance in accordance with the method of the present invention.
Several of the colouring compounds described above may, in addition to their colouring properties, be useful for their health improving effects. Such health improving effects are well described in the art and includes antioxidant activities, diminished risk of cancer, skin protection, protection against age related macularar degeneration and protection against heart diseases.
In accordance with the invention, the colouring substance of the composition is preferably present in the form of bodies of an average largest dimension which is at the most 10 xcexcm. More preferably, the colouring substance is in the form of bodies having an average largest dimension of at the most 5 xcexcm, in particular at the most 2 xcexcm including an average largest dimension of at the most 1 xcexcm, e.g. at the most 0.1 xcexcm such as at the most 0.01 xcexcm. It is contemplated that the ability of the colouring substance to provide an attractive colour hue and to provide an efficient colouring, e.g. when the composition is used in coating compositions, is increasing with decreasing size of the colouring substance bodies. The colour saturation, colour hue and the transparency of coloured products can be controlled by appropriately selecting the size of the bodies of colouring substances.
There are several ways to classify the colour of a substance. Generally the colour characteristics of a substance may be characterised by three parameters, the hue, the saturation and the lightness.
Hue is an attribute associated with each of the dominant wavelengths of the visible spectrum and reflects the dominant colour of the composition (reddish, yellowish, bluish, etc.). Saturation pertains to the intensity of the colour composition and lightness reflects the amount of white or black in the colour composition.
When measured in a tristimulus system, e.g. a Minolta 310 apparatus, saturation is expressed by the parameters xe2x80x9cchromaxe2x80x9d, hue is expressed in degrees by the parameter H and L is expressed by the parameter L. Chroma, H and L, measured at a standard pigment concentration, may be used as a way of characterising and comparing different colour preparations of the same pigment. Especially the chroma is very important. Generally a high chroma for a certain pigment concentration is desirable. Accordingly, a colour may be characterised by its chroma value reflecting the xe2x80x9ccolouring strengthxe2x80x9d or xe2x80x9ccolouring powerxe2x80x9d of the substance.
In accordance with one useful embodiment, the colouring substance bodies in the composition are solid particles, such as e.g. solid particles of a carotenoid, carmine, curcumin, a porphyrin pigment including chlorophyllin, and vegetable carbon black.
The invention encompasses, as it is mentioned above, use of colouring substances that are water insoluble or sparingly soluble in aqueous media at about neutral pH or below or at pH levels of up till about 9, but soluble in alkaline aqueous media. It will be appreciated that it is possible to obtain solid particles of such colouring substances by precipitation of the colouring substances caused by acidifying an alkaline solution of the substance.
The selection of a suitable amount of the colouring substance in the composition according to the invention depends on the particular type of colouring substance and the particular intended application for the composition and a wide range of the amount of colouring substance is therefore contemplated such as a range of 0.5-90 wt % of the composition, although amounts in excess of this range are also envisaged. In preferred embodiments, the amount of colouring substance is in the range of 1-50 wt % and it is in useful embodiments in the range of 5-40 wt %. Based on the dispersion as it is initially prepared, a useful amount of colouring substance is in the range of 2-30 wt % including 5-10 wt %.
In accordance with the invention, the composition may comprise an aqueous phase that, as a further component, comprises a plasticising agent such as a carbohydrate or a sugar alcohol or a mixture thereof. The carbohydrate is preferably selected from a monosaccharide, a disaccharide and an oligosaccharide including as example glucose, lactose, fructose and sucrose. The sugar alcohol can e.g. be selected from sorbitol, mannitol, dulcitol, adonitol and glycerol. The amount of the plasticising agent is preferably in the range of 0-95 wt % of the dispersion, such as in the range of 5-50 wt % including the range of 10-30 wt % of the composition.
Whereas for certain applications it is preferred to provide the colouring substance in the form of solid particles, the colouring substance can also be provided in the form of droplets of an oleoresin colouring substance or droplets of a dispersion or an emulsion of a colouring substance.
For certain applications the composition of the invention is conveniently provided as a composition comprising water in excess of 10 wt %. One advantage of such a composition is the possibility to provide it with a water content within a wide range whereby the composition can be adapted to particular customer demands. A composition containing at least 10 wt % of water having a low content of water will appear as a powder or a viscous paste. Depending on the colouring substance, a composition having a water content in the range of 10-40 wt % will, depending on the water content, typically appear as a powder, a paste, a gel or a viscous liquid. With an increasing water content above this vessel, i.e. in excess of 40 wt % water, the consistency of the composition will acquire an increasingly lower viscosity and become increasingly liquid. It is contemplated that a concentrated pasty composition will be advantageous from a user point of view, since it can easily be distributed and stored and furthermore, the colouring substance will be protected well against light and oxidation in such a concentrate. It is evident that a concentrate composition according to the invention can be diluted with water or any other diluent to any desired content of colouring substance.
In other useful embodiments, the composition according to the invention has a water content of at the most 10 wt %, such as at the most 7.5 wt % or at the most 5 wt %. Such a composition appears as a dry product which, depending on the manufacturing process, may be in the form of e.g. a powder, a granulate or a flaked product. A dry composition according to the invention is provided by at least partially dehydrating the initial dispersion or suspension, e.g. by any conventional drying process including any of the processes disclosed in WO 91/06292 to which there is referred. Thus, a final dried composition according to the invention may optionally contain a spray drying excipient such as e.g. a starch component.
Whereas it has been found that beet pectin, chicory pectin and/or Jerusalem artichoke pectin is highly effective as a wetting and/or dispersing agent in the manufacturing of the composition of the invention, it is within the scope of the invention to apply at least one further hydrocolloid including those hydrocolloids that are mentioned in WO 97/26803 to which there is referred. Such a further hydrocolloid is e.g. selected from a protein including gelatine or soybean protein, a polysaccharide such as e.g. a modified starch or a cellulose derivative, or a gum. It is also possible to combine beet pectin, chicory pectin and/or Jerusalem artichoke pectin with one or more other pectins including pectins derived from apples or citrus fruit.
It will be appreciated that the present composition may contain further additive components conventionally used in colouring substance or pigment compositions such as an antioxidant, a preservative, a wetting agent, a pH regulating agent, a surfactant, an emulsifier or a dispersing agent.
It is another objective of the present invention to provide a method of producing a colouring substance composition as described above, said method comprising as an initial step that a dispersion of the colouring substance is prepared by comminuting the colouring substance in an aqueous phase comprising beet pectin, chicory pectin and/or Jerusalem artichoke pectin in an amount of at least 1% of the colouring substance to obtain a dispersion containing the colouring substance in the form of bodies of the substances that are at least partially coated or encapsulated with the pectin.
In a first step of this method, a dispersion of the colouring substance is prepared by mixing the colouring substance into an aqueous phase. The mixing step is preferably carried out without the addition of other surface-active substances than the pectin and optionally further hydrocolloids. The mixing step can be carried out using any conventional mixing or blending method known in the art. Optionally, the mixing is followed by communication to obtain discrete colouring substance bodies having a largest average dimension of at the most 10 xcexcm. However, it is generally preferred to continue the communication until the colouring substance is in the form of bodies having an average size of at the most 5 xcexcm, preferably at the most 2 xcexcm and more preferably at the most 1 xcexcm. It may also be advantageous to let the comminution proceed until an average largest dimension of at the most 0.1 xcexcm such as at the most 0.01 xcexcm is achieved. The above communication may be repeated one or more times in order to obtain the desired body size.
Applicable comminution methods include milling, e.g. using a ball mill, as it described in the below examples.
The step of dispersing the colouring substance can, if desired, be carried out in at least two steps in which an additional amount of pectin is added in the second and/or any subsequent step. It will be understood that the method of the invention may also comprise the preparation of a colouring substance dispersion in which mixtures of two or more colouring substances are used. In this manner, colouring substance compositions having a particularly attractive colour can be provided as the result of the combination of two or more colouring substances having different colour hue or saturation.
As mentioned above, the method of the invention may comprise the addition to the aqueous phase of a plasticising agent such as a carbohydrate or a sugar alcohol either before or after the mixing of the colouring substance, or it may include the incorporation into the dispersion of at least one further component e.g. selected from an antioxidant, a stablising agent, a viscosity modifying agent, an alcohol, a resin or a preservative agent.
In useful embodiments, the above method includes a further step of at least partially rehydrating the pigment dispersion to obtain a composition containing less than 10 wt % of water.
In a further aspect the invention pertains to the use of the composition according to the invention as a colouring agent in the manufacturing of an edible product. As used herein, the expression xe2x80x9cedible productxe2x80x9d denotes any solid or liquid food product. Edible products also include the product types referred to as xe2x80x9cnutraceuticalsxe2x80x9d, xe2x80x9cfunctional foodsxe2x80x9d or xe2x80x9chealth foodsxe2x80x9d (these three terms are used interchangeably herein), i.e. food products or food supplements comprising components that are considered to confer certain health improving characteristics. Such products may be in any conventional forms including products in tablet or capsule dosage forms which e.g. may comprise separate compartments. It will be appreciated that when a composition according to the invention is sued in the manufacturing of such nutraceutical products, the colouring substance can, in addition to its colouring effect, also confer to such products a nutritionally and/or health improving effect. As an example, xcex2-carotene, which is a colouring substance belonging to the class of carotenoids, has certain pharmaceutical and/or health improving effects. Other examples of colouring substances or derivatives of colouring substances having pharmaceutical or health improving effects include tocophenols, tocotrienols and polyphenols.
Several food products have an aqueous phase with a pH below 7 and this acidic environment will in many instances render a pigment as such unstable and the pigment will tend to precipitate resulting in a change of the colour. This is e.g. observed in products such as acidified milk products and beverages. The compositions of the present invention are particularly useful in acidic food products as the compositions are acid-proof and do not precipitate.
In other useful embodiments, the composition according to the invention is used for colouring of liquid food products including soft drinks, carbonated beverage products and milk products.
An interesting application of the composition according the invention is the colouring of edible products, the manufacturing of which includes an extrusion step, e.g. edible films for containing a food product such as a meat product or a vegetable product. A typical example hereof is collagen films used as casings for sausage products. An effective amount of the colouring substance composition is added to the aqueous mixture to be extruded or casted and the resulting edible film will contain the colouring substance. It has been found that the colouring substances when incorporated in such extruded edible films substantially do not migrate into the contained food product and furthermore, the colouring substance is not released into water in which the products are cooked. Use of edible films for covering vegetables are increasing as it confers an improved shelf-life to vegetables which are normally stored individually and unprotected in the retail shops. Such covering films for use for e.g. tomatoes may advantageously be coloured by a composition of the invention.
Other examples of extruded products where the composition according to the invention is useful include breakfast cereals, cakes, breads, snacks, confectionery products, breadings, crisps and grains. It has been found that the fact that the compositions do not contain any lipids for surface active substances make them particularly useful in the manufacturing of expanded products made by an extrusion process, as the expansion in such processes is lower when lipids and/or surface active substances are added to the extrusion mixture.
A further advantageous use of the compositions is the colouring of confectionery products including as examples candies, acid drops and jelly products, since the colouring substances in the compositions according to the invention are acid stable.
Several food products such as e.g. soft drinks, juices, soups and sauces are manufactured as initially liquid products which are subsequently dehydrated to a dry storage stable product typically having a water content of at the most 10 wt %. The compositions according to the invention are also useful for the colouring of such products in that the colouring of the products after rehydration will substantially be of the same strength and hue as the starting liquid food product prior to dehydration.
It is a well-known problem in the food industry that colouring agents used in food products tend to migrate within the food product or into the environment of the product. This phenomenon is also referred to in the art as xe2x80x9cbleedingxe2x80x9d. This problem is particularly troublesome if it occurs in food products that comprise multiple, separated compartments or layers where the colouring agent is not added to all of such compartments. A colouring agent which does not migrate in such products is therefore highly desirable in the industry. It has been found that the colouring substances of the compositions according to the invention are retained in the compartment(s) to which they have been added and do not migrate into adjacent non-coloured compartments.
One typical example of such a compartmentalised or layered food product is dessert products, which optionally are acidulated and which comprise at least one layer of fruit filling, e.g. in the form of jelly, to which a colouring agent is added, and one or more layers of other ingredients also having an aqueous phase to which the colouring agent is not added. Another example of such a product is layered cake. It is evident that migration of colouring agent into the non-coloured layers results in a highly unacceptable appearance of these layered products. The composition according to the invention can be used in such products without giving rise to xe2x80x9cbleedingxe2x80x9d problems. A further example of a product where it is advantageous to avoid migration of colouring substances is a cereal breakfast product to be eaten with milk.
Avoidance of migration of colouring substances is also critical in connection with edible products comprising a surface decoration layer in which a colouring agent is dispersed. Clearly, it is undesirable if the added colouring substance migrates from the decoration layer into the adjacent product layer. Typical examples of surface decorated products are meat products such as surimi and other delicatessen products where the decoration e.g. may be in the form of a water-based gel which is coloured with the colouring substance composition whilst liquid and subsequently applied on the product to solidify. Further examples of surface decorated products are bakery products having sugar icing (glazing) or coloured decoration particles on top. When added to such decoration layers or particles, the colouring substances of the compositions according to the invention do not migrate from such layers or particles.
Dragees constitute a particular type of edible multilayered products where one or more coating layers are applied onto a centre of an edible component. Examples of such centres to be coated include chewing gum, sugar granulates, sugar tablets and chocolate. Colouring of such centres is typically carried out in one or more panning steps where the centres are coated with sugar syrup containing the colouring agent. Normally, it is required to apply several coating layers to obtain a sufficient covering with colouring substance. With known water soluble or water dispersible colouring substance compositions based on lakes it is frequently required to apply 20 coating layers or more. It has been found that the compositions according to the invention are highly suitable for such coating purposes and that dragees with a sufficient colouring can be obtained by applying less than 20 layers, such as 2-15 layers. Furthermore, it has been found that the colouring substances of the compositions of the invention as contained in coating layers do not come off on fingers on handling or on mucosal surfaces when the dragees are consumed.
A highly attractive characteristic of the compositions according to the invention is that they are uesful as colouring agents in the manufacturing of pharmaceutical products. Thus, the compositions can be used for colouring of pharmaceutical products comprising multiple, separated compartments essentially in the same manner and with the same advantages as described above for compartmentalised food products. In particular, the compositions are useful for colouring of compositions for conventional film-coating of tablets, pills or granules containing pharmaceutically active substances.
For such coating purposes, the water dispersible compositions of the invention are typically added to a sugar syrup suspension, e.g. based on sucrose. The solid content of such a coating syrup is normally in the range of 60-80 wt %. The amount of the colouring composition of the invention which is added to the coating syrup is generally in the range of 0.5 to 50 wt % of the syrup. The thus coloured coating mixture may contain further components such as stabilisers, preservative, viscosity modifying agents and plasticisers.
The pharmaceutical centres are coated repeatedly in a conventional panning process and the number of repeated coatings that are required depends on the particular pigment and the desired appearance of the finished product. However, with the composition according to the invention, relatively few coating layers are required to obtain an attractive colouring. Thus, less than 20 layers are normally required and in most cases, 5-15 layers will suffice.
In addition to the above applications of the present colouring substance compositions, they are also useful for colouring of pharmaceutical products in liquid form such as solutions, suspensions or dispersions having an aqueous phase.
In a further aspect of the present invention a colouring composition is provided which when tested in a soft drink system is characterised by the colouring characteristics given by the measurements of the composition using a Minolta Tristimulus CT 310 apparatus, when tested in a soft drink system. The test soft drink system contains: sucrose, 430.0 g; Na-benzoate, 0.7 g; K-sorbate, 0.9 g; Ascorbic acid, 0.1 g; Citric acid mono-hydrate, food grade, 8.6 g and demineralised water added to 1 liter and further diluted to 5 liter. When tested in this system colouring compositions containing turmeric (30 ppm) resulted in a chroma value of at least 30, colouring compositions containing bixin (30 ppm) resulted in a chroma value of at least 25 and colouring compositions containing chlorophylin (20 ppm) resulted in chroma value of at least 33.
The invention will now be further illustrated in the following non-limiting examples.

Coloring substance composition and a method of manufacturing same


Biodegradable polymer blends suitable for laminate coatings, wraps and other packaging materials are manufactured from at least one “hard” biopolymer and at least one “soft” biopolymer. “Hard” biopolymers tend to be more brittle and rigid and typically have a glass transition temperature greater than about 10° C. “Soft” biopolymers tend to be more flexible and pliable and typically have a glass transition temperature less than about 0° C. While hard and soft polymers each possess certain intrinsic benefits, certain blends of hard and soft polymers have been discovered which possess synergistic properties superior to those of either hard or soft polymers by themselves. Biodegradable polymers include polyesters, polyesteramides, polyesterurethanes, thermoplastic starch, and other natural polymers. The polymer blends may optionally include an inorganic filler. Films and sheets made from the polymer blends may be textured so as to increase the bulk hand feel. Wraps will typically be manufactured to have good “dead-fold” properties so as to remain in a wrapped position and not spring back to an “unwrapped” form.

1. The Field of the Invention
The present invention relates generally to biodegradable polymer blends and articles manufactured therefrom. More particularly, the present invention relates to blends of two or more biopolymers and/or blends of biopolymers and fillers that yield sheets and films having improved physical properties, such as flexibility, elongation and/or dead-fold. The biodegradable polymer blends may be suitable for a number of applications, such as in the manufacture of disposable wraps, bags and other packaging materials or as coating materials.
2. The Relevant Technology
As affluence grows, so does the ability to purchase and accumulate more things. Never before in the history of the world has their been such a large number of people with such tremendous buying power. The ability to purchase relatively inexpensive goods, such as books, tools, toys and food, is a luxury enjoyed by virtually all levels of society, even those considered to be at the poorer end of the spectrum. Because a large percentage of what is purchased must be prepackaged, there has been a tremendous increase in the amount of disposable packaging materials that are routinely discarded into the environment as solid waste. Thus, as society becomes more affluent, it generates more trash.
Some packaging materials are only intended for a single use, such as boxes, cartons, pouches, bags and wraps used to package items purchased from wholesale and retail outlets. Even the advent of computers and "paperless" transactions has not stemmed the rising tide of packaging wastes. Indeed, the onset of "e-commerce" has spawned a great mail-order fad, thus creating a whole new market of individually packaged and shipped items.
Moreover, the modern, fast-paced lifestyle has greatly disrupted traditional eating routines in which people prepared their own meals and sat down as a family or group. Instead, people grab food on the run, thus creating ever-increasing amounts of fast food packaging materials that are used once and then discarded. In view of the high volume of disposable packaging materials being generated, some countries, particularly those in Europe, have begun to mandate either the recycling of fast food generated wastes or the use of packaging materials which are "biodegradable" or "compostable". Environmental activists commonly pressure companies that generate solid waste. As a result, large fast food chains such as McDonald's have been essentially forced to discontinue the use of certain nonbiodegradable packaging materials such as foamed polystyrene, either by government fiat or by pressure by environmental groups. McDonald's currently uses a combination of paper wraps and cardboard boxes as an interim solution until more environmentally friendly packaging materials can be made on a commercial basis. There is therefore an ever-present need to develop biodegradable alternatives to nonbiodegradable paper, plastics and metals.
In response to the demand for more environmentally friendly packaging materials, a number of new biopolymers have been developed that have been shown to biodegrade when discarded into the environment. Some of the larger players in the biodegradable plastics market include such well-known chemical companies as DuPont, BASF, Cargill-Dow Polymers, Union Carbide, Bayer, Monsanto, Mitsui and Eastman Chemical. Each of these companies has developed one or more classes or types of biopolymers. For example, both BASF and Eastman Chemical have developed biopolymers known as "aliphatic-aromatic" copolymers, sold under the trade names ECOFLEX and EASTAR BIO, respectively. Bayer has developed polyesteramides under the trade name BAK. Du Pont has developed BIOMAX, a modified polyethylene terephthalate (PET). Cargill-Dow has sold a variety of biopolymers based on polylactic acid (PLA). Monsanto developed a class of polymers known as polyhydroxyalkanoates (PHA), which include polyhydroxybutyrates (PHB), polyhydroxyvalerates (PHV), and polyhydroxybutyrate-hydroxyvalerate copolymers (PHBV). Union Carbide manufactures polycaprolactone (PCL) under the trade name TONE.
Each of the foregoing biopolymers has unique properties, benefits and weaknesses. For example, biopolymers such as BIOMAX, BAK, PHB and PLA tend to be strong but are also quite rigid or even brittle. This makes them poor candidates when flexible sheets or films are desired, such as for use in making wraps, bags and other packaging materials requiring good bend and folding capability. In the case of BIOMAX, DuPont does not presently provide specifications or conditions suitable for blowing films therefrom, thus indicating that it may not be presently believed that films can be blown from BIOMAX and similar polymers.
On the other hand, biopolymers such as PHBV, ECOFLEX and EASTAR BIO are many times more flexible compared to the more rigid biopolymers discussed immediately above. However, they have relatively low melting points such that they tend to be self adhering and unstable when newly processed and/or exposed to heat. While initially easily blown into films, such films are often difficult to process on a mass scale since they will tend to self adhere when rolled onto spools, which is typically required for sale and transport to other locations and companies. To prevent self-adhesion (or "blocking") of such films, it is typically necessary to incorporate a small amount (e.g. 0.15% by weight) of silica, talc or other fillers.
Another important criteria for sheets and films used in packaging is temperature stability. "Temperature stability" is the ability to maintain desired properties even when exposed to elevated or depressed temperatures, or a large range of temperatures, which may be encountered during shipping or storage. For example, many of the more flexible biopolymers tend to become soft and sticky if heated significantly above room temperature, thus compromising their ability to maintain their desired packaging properties. Other polymers can become rigid and brittle upon being cooled significantly below freezing (i.e., 0° C.). Thus, certain homopolymers or copolymers may not by themselves have sufficient stability within large temperature ranges.
In the case of the packaging of foods, such as refrigerated meats or fast foods, the packaging materials may be subjected to widely fluctuating temperatures, often being exposed to rapid changes in temperature. A biopolymer that may be perfectly suitable at room temperature, for example, may become completely unsuitable when used to wrap hot foods, particularly foods that emit significant quantities of hot water vapor or steam. In the case of meats, a wrapping that may be suitable when used at room temperature or below, such as at refrigeration or freezing temperatures, might become soft and sticky during microwave thawing of the meat. Of course, it would generally be unacceptable for a biopolymer to melt or adhere to the meat or fast food being served unless it was desired for some reason that the person actually consume the biopolymer.
Another factor that impacts whether a particular material is suitable for use as a wrap (e.g. sandwich or meat wrap) is whether sheets or films formed therefrom have suitable "dead-fold" properties. The term "dead-fold" is a measurement of the tendency of a sheet or film to remain in a desired orientation once used to encapsulate, enclose, wrap or otherwise enclose at least a portion of an item to be packaged. Wraps made from paper, for example, typically have modest to excellent dead fold properties depending on how the paper has been processed or treated. On the other hand, many plastic films or sheets (e.g. polyethylene) have very poor dead-fold properties such that they make very poor wraps. Instead, they are better suited for other uses, such as sacks, bags, pouches, coverings, etc. where good dead-fold is not necessary or desirable. In order to compensate for generally poor dead-fold properties, plastic wraps are typically manufactured to have high self-cling (e.g. SARAN WRAP). Self cling is a property having little to do with dead-fold, and is akin to the use of adhesives. One problem with self cling wraps is that they can be very difficult to handle. A self-cling wrap that is accidentally allowed to cling to itself before being used to wrap the substrate becomes useless and must be discarded and replaced with another length of self-cling wrap.
Paper also breathes (i.e. transmits gas) and has good water vapor transmission unless completely sealed with a wax or plastic. Plastic films and sheets, on the other hand, generally have very poor water vapor transmission and breathability. As a result, paper is a much better as a wrap for hot foods than plastic sheets because it permits the escape of water vapor. A plastic sheet, on the other hand, will retain virtually all of the water vapor, which condenses over time on the plastic surface and can make the food soggy, particularly a bun or slice of bread.
In view of the foregoing, it would be an advancement in the art to provide biodegradable polymers which could be readily formed into sheets and films that had strength and flexibility properties suitable for use as packaging materials and that had suitable temperature stability for a given use. In addition or alternatively, it would also be an advancement in the packaging art to provide improved biodegradable polymers that could be formed into sheets and films having sufficient dead-fold so that they could be folded, wrapped or otherwise manipulated in order to reliably enclose a substrate therein. In addition or alternatively, it would be a further advancement in the packaging art to provide improved biodegradable sheets and films that had enhanced breathability and water vapor transmission compared to conventional plastic sheets.
Such improved biopolymers, as well as sheets and films formed therefrom, are disclosed and claimed herein.

This patent is subject to a terminal disclaimer.

Biodegradable polymer blends for use in making films, sheets and other articles of manufacture

bio-tec Biologische Naturverpackungen GmbH & Co., KG


An assembly includes at least one first element comprising at least one first electrical bonding pad; at least one second element comprising at least one second electrical bonding pad; electrical and mechanical interconnect means, wherein the electrical and mechanical interconnect means comprise at least: at least one first intermediate metal interconnect element, on the surface of at least the first electrical bonding pad; at least one sintered joint of metal microparticles or nanoparticles stacked with the first intermediate metal interconnect element; the melting point of the first intermediate metal interconnect element being greater than the sintering temperature of the metal microparticles or nanoparticles. A method for fabricating an assembly is also provided.

The 3D assembly solutions are of great interest for various applications in microelectronics and in power electronics. The connections between the chip and the circuit can be produced by different techniques and in particular by wired cabling, commonly called "wire bonding", by ribbon cables or by "flip chip" mounting-type technologies.
Microcabling or wire assembly is the oldest and most widely used technology in the microelectronics industry for producing the interconnect of a "chip" circuit with its environment (package, printed circuit board, hybrid circuit, etc). It can involve "Wedge bonding" or "Ball bonding":                in the "wedge bonding" technique, a wire, most commonly of aluminum, is fed by the tool (called stylus or needle), then applied to the pad to be soldered. The link between the wire and the zone to be connected is made by combining pressure and ultrasound vibration. This is a "cold" soldering. It is the ultrasound energy which causes a softening of the wire similar to the effect obtained by a temperature rise. The wire is then guided by the tool onto the second pad and a soldering is performed;        in the "ball bonding" technique, for example, a gold wire passes through a heated capillary tube (100 to 200° C.). The ball formed at the output of the capillary tube (by the discharging of a capacitor or by a hydrogen flame) is soldered onto an output pad of the circuit. The capillary tube is then displaced to perform the second soldering. The wire is torn away by the capillary tube, a new ball is reformed and a new connection can be made.
The advantages of the "flip chip" assemblies are numerous, such as the strong integration, the low strain inductance, and a better discharging of the heat flux generated by the semiconductors.
The production of the interconnects with solder "bumps" is one of the techniques most widely used in "flip chip" assembly, and consists in depositing paste to be soldered on bonding pads, commonly referred to by the person skilled in the art as "pad", located on the circuit or on the electronic component, then in aligning the component and the circuit to match each circuit "pad" with the semiconductor "pad".
The circuit and the substrate are placed in contact and a soldering method is applied that makes it possible to ensure the electrical and mechanical contact between the semiconductor and the substrate. This technique is not practical for all the applications and can have a number of disadvantages such as the need for specific metal layers on the pads to be connected, involving additional methods and, consequently, high costs, the need for a temperature at least equal to the melting point of the solder, and the difficulty in making up a difference of several μm or several tens of μm in height that may be present on some components. Furthermore, the soldering method induces a risk of short circuit that is not inconsiderable when the distances between electrodes are small following the flow of the solder during melting thereof.
Another alternative such as direct sintering of nanoparticles can be used as described in the patent U.S. Pat. No. 8,257,795 B2 "Nanoscale metal paste for interconnect and method of use". It consists in replacing the connection commonly called solder "bump" of the solder "bump" technique with a nanoparticle paste (Ag, Au or Cu) to be sintered. This technology also presents drawbacks such as the need for an appropriate metallization of the pads (Au or Ag but not compatible with the Al very often used as finish for electronic chips). A second disadvantage with this technique is the low height of the joint (generally 10 microns) which can limit the thermomechanical reliability of the joints and the choice of the underfills (encapsulating materials) which have to fill the gaps (more often than not by capillarity).
The interconnect by "stud bump", for its part, consists in using a "ball bonding" wiring machine.
More specifically, a ball of the metal is attached to the pad by the use of the thermosonic or thermocompression techniques. The wire is cut just after the ball forming the "stud bump" form, also called intermediate interconnect element. Next, the "stud bumps" formed on the bonding pad of the semiconductor or on that of the circuit are attached to the other bonding pad by thermocompression. One drawback with this technique is the possibility of having problems of adhesion between the metallization and the "stud bump" in the thermocompression due to the absence or the small thickness of the necessary metal layer. The patent US 2002/0093108 A1 "FLIP CHIP PACKAGED SEMICONDUCTOR DEVICE HAVING DOUBLE STUD BUMPS AND METHOD OF FORMING SAME" makes it possible to avoid this problem by producing "stud bumps" on the circuit and semiconductor side and by then thermocompressing "stud bump" on "stud bump". The second drawback is the need for a pressure and a high temperature to ensure the assembly by thermocompression which is not compatible with pressure-sensitive components. Furthermore, this assembly technique does not make it possible to make up a difference in height of several μm or several tens of μm that may be present on some components following the fabrication method.

Assembly comprising hybrid interconnecting means including intermediate interconnecting elements and sintered metal joints, and manufacturing process

COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES


An apparatus for measuring jitter in a digital signal that includes an offset unit arranged to form an offset reference clock signal, being offset by a predetermined frequency amount from the digital signal. The apparatus also includes a sampler arranged to sample the digital signal at sampling times determined by the offset reference clock signal such that, in the absence of jitter and the offset by a predetermined frequency, there are a predetermined number of sampling times in each bit of the digital signal. The apparatus further includes at least one detector arranged to detect occasions when the number of sampling items in any bit of the digital signal is different from the predetermined number, and a counter arranged to count the occasions over a predetermined time. Also the apparatus includes an analyzer arranged to derive at least one measure of jitter from the counting of the occasions.

1. Field of the Invention
The present invention relates to the measurement of jitter in a digital signal. In theory, the spacing of the transitions between levels of a digital signal have a completely uniform spacing. In practice, particularly during transmission, there may be minute variations in the actual time of the transition, relative to the theoretical transition time defined by an absolute reference clock. These variations are referred to as jitter, and may be considered to be a spurious phase modulation of the signal.
2. Summary of the Prior Art
Known systems for measuring jitter involve a very stable phase-locked loop which compares the pulse train containing jitter with an internally generated, jitter-free reference clock. The phase-locked loop has a generator for generating the reference clock, the output of which is fed to the input of a phase demodulator which also receives a digital signal containing jitter. The phase demodulator converts the signal to pulse duration modulation, which is output to a low pass filter, the output of which gives the jitter measurement, and also is fed back to the input of the reference clock generator, to form the loop. The low pass filter has cut off frequency of 5-10% of the bit rate. But since the digital signal being investigated may contain long sequences of digital zeros, a pattern/clock converter may be used to convert the digital signal into a continuous pulse train with the same jitter as the original signal, which pulse train then forms the input to the phase demodulator. Analysis of the output may involve peak value rectification before the results are displayed, and/or analysis with a spectrum analyser.
As mentioned above, such a jitter measurement system involves a low pass filter, and this has a significant influence on the greatest measurable jitter frequency component. The known systems also involve many analog circuits, which are more expensive than digital components.


The resolution, in terms of numbers of pixels in horizontal and vertical directions, and frame rate, in terms of frames per second, of video data are converted by assembling a group of the frames within an input buffer, by applying a direct DCT to data from each line of pixels extending along a scan line and among scan lines, perpendicular to the scan lines, and to a line of pixels extending at each pixel position among the group of frames, and by applying an interpolating inverse DCT to coefficients generated by the direct DCT. Preferably, to prevent the formation of artifacts, the application of the direct DCT to data from a line of pixels is interrupted when a difference in a coordinate data value between adjacent pixels exceeds a threshold limit.

1. Field of Invention
The present invention relates generally to enlarging two- and three-dimensional digital data arrays representing physical entities, and more particularly to the application of the Discrete Cosine Transform (DCT) as an interpolation function for video data. This invention has application in the up-conversion or down-conversion of video formats, i.e., for the purpose of HDTV format conversion.
2. Description of Prior Art
The use of mathematical functions for the purpose of up-sampling (interpolation) to increase a number of data points and for down-sampling to reduce a number of data points is well-known. Examples of the use of such functions will now be explained with reference to FIGS. 1–3.
FIG. 1 is a data flow chart showing the conventional application of the average function, which is perhaps the simplest interpolation function, to data points 10 described by formulas 12 forming new data points 14, described by formulas 16. Each of these new, intermediate data points has a value that is the average of the adjacent data points. Many additional filters having special properties (blurring, sharpening, contrast enhancement, etc.) have been described in the literature.
It is well established in the literature of the field of video compression that video can be well-modeled as a stationary Markov-1 process. This statistical model predicts the video behavior quite well, with measured correlations as high as 0.99 in the frame direction.
It is also well-known the Karhunen-Loeve Transform (KLT) perfectly decorrelates Markov-distributed video. This means the basis of the KLT is an independent set of vectors which encode (i.e., predict) the pixel values of the video sequence.
It is a further result that many discrete transforms well approximate the KLT for large correlation values. Perhaps the best-known such function is the DCT, although many other functions (DST, WHT, etc.) serve as reasonable approximations to the KLT.
If a discrete transform that approximates the KLT representation is considered a continuous function, that function ideally approximates the video in that each of the independent basis functions predicts video values smoothed at the sampling rate of the original video. Thus the sampled IDCT (or polynomially-fit IKLT coefficients, IDST, or other continuous approximation to the inverse KLT) forms an optimal filter for prediction of interpolated pixel values.
The patent literature includes a number of patents and publications describing methods for using interpolation functions to expand an image array in the horizontal and/or vertical directions. For example, U.S. Pat. No. 6,141,017 to Cubillo et al. describes a method and apparatus using data interpolation to provide a scaled expanded image array of an original image array representing a physical entity, such as an image or sequence of frames, by utilizing fractal transform methods. Fractal transform methods are used to select a best domain/range block correspondence in an original image array, with the range block being larger than the domain block. A subset of the data values in the range block is selected. Finally, an area of the expanded image array is populated with the data values in the selected subset where the area corresponds to the domain block location in the original image array.
U.S. Pat. App. Pub. No. 2002/0136293 to Washino describes a multi-format digital video production system enabling a user to process an input video program to produce an output video of the program in a final format, which may have a different frame rate, pixel dimensions, or both. In the preferred embodiment, specialized graphics processing capabilities are included in a high-performance personal computer or workstation. Images are resized horizontally and vertically by pixel interpolation. Frame rates are adapted by inter-frame interpolation, or by traditional schemes.
U.S. Pat. No. 6,356,315 to Chen et al. describes a method for achieving magnification or reduction by a single FIR filter under the control of a DDA (digital differential amplifier) as would be used to simulate a perfectly straight line on a two-dimensional raster. The single FIR filter combines the processes of interpolation, filtering, and decimation. The DDA is programmed with the desired magnification or reduction ratio to provide signals that control shifting of input samples into the FIR filter and selection of FIR coefficients for the FIR filter.
U.S. Pat. App. Pub. No. 2002/01364446 to Slavin describes a system and method for producing a resampled image from a source image by solving coefficients for a cubic polynomial transition model.
U.S. Pat. App. Pub. No. 2002/0009225 to Takahashi et al. describes a resolution conversion method in which an image signal expressing pel (pixel) values and a significance signal indicating whether the pel is significant are supplied as input signals.
By referring to the input significance signal values for the pels proximal to the pel being processed, the significant pels are identified, and a resolution conversion characteristics selector selects one of two or more frequency conversion characteristics to be used for resolution conversion of the image signal using only significant pels.
U.S. Pat. App. Pub. No. 2001/0024515 to Martins, et al. describes a method and apparatus to interpolate video frames, in which the method comprises, for a plurality of interpolated pixels in an interpolated video frame, classifying an interpolated pixel of the plurality as one of stationary, moving, covered, and uncovered, and then setting components of the interpolated pixel in components of a previous pixel from a previous video frame, the previous pixel corresponding to the interpolated pixel in the video frame.
U.S. Pat. No. 5,657,082 to Harada et al. describes an imaging apparatus capable of outputting video signals. The imaging apparatus includes: a color separating optical system for separating incident image light into light beams of primary colors; first, second, and third imaging portions respectively including a first, second, and third set of pixels arranged at regular pitches in a first direction and in a second direction which is perpendicular to the first direction, the first, second, and third imaging portion receiving each one of the light beams of the primary colors and respectively accumulating them in the first, second, and third set of pixels, as the image signal, the first set of pixels being shifted by ½ pitch with respect to the second and third set of pixels in the first direction and the second direction; an A/D converter for converting the image signals of primary colors accumulated in the first, second, and third sets of pixels into digital signals; an interpolation processor for performing interpolation processing to the image signals of the primary colors which are converted into the digital signals in the A/D conversion, thereby doubling the number of pixels in the second direction; and a pixel number converter for converting the image signals of primary colors which are interpolated in the interpolation processor into image signals based on any one of the plurality of formats.
A number of other patents describe methods for interpolating the movements of visual objects occurring among frames of data to increase the number of frames per second in moving video data. For example, U.S. Pat. No. 6,229,570 to Bugwadia et al. describes a process for up-converting an existing video source signal having a low frequency, in frames per second, to a high frequency signal for use with HDTV (high definition television). The process samples the existing frames in the existing video signal and calculates integer displacements of pels (pixels) within the existing frames. A polynomial curve fit is then performed on the displacements to obtain estimates of horizontal and vertical displacements of each block in each existing frame. Based on the alignments of the blocks within a sampling grid on each frame, the blocks are segregated into groups. The block groups are then used to interpolate missing or required frames of the high frequency signal in a piecemeal manner by utilizing blocks of a particular block group to estimate a corresponding block of the high frequency signal.
U.S. Pat. No. 6,377,621 to Borer describes a method for performing improved motion compensated interpolation of moving images using motion vectors of variable reliability. By taking into account the reliability of the motion vectors, produced by a separate motion estimation device, a subjectively pleasing interpolation can be produced. The method allows a gradual transition between motion compensated and non-motion compensated interpolation depending on the reliability of the motion vector used. This is achieved by modifying the temporal interpolation timing, using a look up table, controlled by a vector reliability signal produced by the motion estimator.
U.S. Pat. No. 6,452,639 to Wagner et al. describes a method and system for converting from interlaced to progressive video frames, using an interpolation algorithm that is scalable, having several levels or modes with an increasing computational complexity, depending on the level of resources available for the conversion process.
U.S. Pat. App. Pub. No. 2000/085114 to Ojo, et al. describes a processing circuit for removing interlacing from video signals. The processing circuit comprises a line memory, a de-interlacing circuit, a frame memory, and a cache memory, in which a pixel mixer is interposed between the cache memory and the de-interlacing circuit.
U.S. Pat. App. Pub. No. 2002/0036705 to Lee et al. describes a format converter and method that performs frame-rate conversion and de-interlacing using a bi-directional motion vector. The method includes steps of (a) estimating a bi-directional motion vector between the current frame and the previous frame from a frame to be interpolated; (b) setting the motion vector of a neighboring block that has the minimum error distortion, among motion vectors estimated in step (a); and (c) forming a frame to be interpolated with the motion vector set in step (b).
What is needed is a method applying the same simple process to change both the format of video data, in horizontal and vertical directions, and for varying the frame rate of the video data.
FIG. 2 is a data flow chart showing the application of a first conventional sampling technique for down-sampling to reduce the number of data points 20 described by formulas 22, with intermediate data points are discarded to form data points 24 described by formulas 26.
FIG. 3 is a data flow chart showing the application of a second conventional sampling technique to reduce the number of data points 20 described by formulas 22, with adjacent pairs of values being averaged to form single data points 28 described by formulas 30.
The DCT (discrete cosine transform) is a mathematical transform that is widely used in the compression of still video images to simplify their transmission and storage both for use as still images and for use as portions of motion images. In particular, the DCT is used in the JPEG (Joint Photographic Experts Group) standard for digital compression, which is the most popular method for digital compression of still images, with the DCT transform being easily implemented in both software and hardware.
The JPEG video compression process begins with subdividing a video image into a number of macroblocks, each of which includes 64 pixels from an 8×8 square block of the original image. Each of these macroblocks is then sent into the DCT-based encoder portion of the compression routine, with a functional unit called the FDCT (forward discrete cosine transform) receiving the macroblock to apply a transform to the pixels therein. The transformed data is then sent to a quantizer, which performs the first stage of compression in which data is lost. The compressed data is then sent to an entropy encoder, in which a coding system such as Huffman coding is applied. Finally, the data is converted into a bit stream for storage or for immediate transmission.
The JPEG decompression technique is symmetrical with the compression technique, applying inverse processes to reverse the processes previously applied. The process begins with an entropy decoder, which undoes the process performed by the entropy encoder. Data from the entropy decoder moves to a dequantization stage, and, then, to a stage applying an IDCT (inverse discrete cosine transform) process to reverse the FDCT process applied during compression.
A Motion JPEG (M-JPEG) compression technique is an extension of the JPEG technique to handle moving pictures, with each frame in a video sequence being individually compressed using JPEG. Like JPEG, M-JPEG attains compression ratios of 10:1 to 15:1.
The MPEG (Motion Picture Experts Group) uses a much more complex technique to attain compression ratios of 30:1, with some frames in a sequence being encoded as I frames (intra frames), which are self contained, being encoded using a DCT-based technique similar to JPEG. Other frames are encoded as P frames (predicted frames) using forward predictive coding, in which the actual frame is coded with reference to a previous I or P frame. Other frames are encoded as B frames (bidirectional or interpolated frames) that are coded using a past frame and a future frame, which may be I or P frames, as reference frames.
The patent literature further includes a number of patents describing systems and methods for improving the implementation of IDCT transforms to decompress video input signals transmitted according to the MPEG standard, and particularly to decompress such input signals to provide variations in the resolution and frame rate of the resulting video signals. For example, U.S. Pat. No. 5,563,660 to Tsukagoshi describes an apparatus for expanding a compressed digital video signal representing a motion picture to provide a digital video output signal. The apparatus includes a decoder for the compressed digital video signal using a common memory for decoding and for a ⅔ pull-down conversion of the reconstructed interlaced frames stored in the frame memory with a frame rate of 24 Hz to provide the pictures of the digital video output signal with a picture rate of at least 49 Hz.
U.S. Pat. App. Pub. No. 2002/0136308 to La Maguet et al. describes a method for generating a down-sampled video from an input coded video coded according to a block-based technique and comprising quantized DCT coefficients defining DCT blocks. The down-sampled video is composed of frames having a smaller format than the frame used to produce the input coded video.
U.S. Pat. No. 6,442,201 to Choi describes a down-conversion decoding device of a digital television producing a high-quality video image from a coded video signal with a reduced-size memory.
U.S. Pat. App. Pub. No. 2002/0141501 to Krishnamachari describes a system that increases a resolution of at least a portion of reference frame of video based on pixels in the reference frame and pixels in one or more succeeding target frames of the video. In the particular case of MPEG-coded video, blocks in the target frames are located using motion vector information present in the MPEG bit stream. Values of additional pixels are determined based on values of pixels in the first block and on values of pixels the one or more blocks, whereafter the additional pixels are added among the pixels in the first block in order to increase the block's resolution.
U.S. Pat. No. 6,456,663 to Kim describes a DCT-domain down conversion system that compensates for an IDCT mismatch to reduce aliasing. In the conversion system, a DCT domain filter is applied to the unquantized DCT coefficient values, and IDCT mismatch control processing is implemented. The DCT domain filter sets the filter coefficient corresponding to the highest frequency band to unity to prevent modification of any coefficient value that has been modified by the IDCT mismatch operation.
U.S. Pat. App. Pub. No. 2001/0055340 to Kim et al. describes an HDTV down conversion system including an apparatus for forming a low-resolution, 2:1 down converted video signal from an encoded video signal representing a video image, with the encoded video signal being a frequency-domain transformed high-resolution video signal with motion prediction.
The DCT is used because it predicts a representation of data that mirrors the statistical behavior of video data. This means that the interpolated data is that which, on the average, would have been present in typical video images. The synthesized higher-resolution image is therefore more accurate than that of any other filter. What is needed is a simple method using the DCT to produce a change both in the resolution of individual frames of video data and in the frame rate at which frames of video data are presented.

Method for converting the resolution and frame rate of video data using Discrete Cosine Transforms


A method of attracting insects selected from the group consisting of houseflies, mosquitoes and wasps to a particular location, which method comprises placing at the said location a lure containing an effective attractant composition which comprises at least one compound which is a substituted benzenederivative having one or more short side chains, the said compound being volatile at room temperature and having a molecular weight in the range of from 115 to 155.

The present invention relates to an insect attractant and, in particular, to an insect attractant for houseflies, mosquitoes or wasps, which can be used to lure the insects to traps or other devices for the purpose of controlling such pests.
Insect attractants have been identified from food, from hosts or host plants of the insects themselves, from other insects (e.g. pheromones which are used in intraspecies chemical communication), and from the random screening of chemical compounds. Certain plants, including tropical pitcher plants (Nepenthes species), trumpet pitcher plants (Sarraceniaceae) and others capture insects and other animals which they are able to digest. The evidence which is summarised in Juniper,B. E., Robins,R. J., & Joel,D. M.(1989) The Carnivorous Plants, Academic Press suggests that the insects are attracted by visual stimuli (color patterns and reflected ultra violet light), and at close range are enticed to feed by the presence of viscous nectar secretions.
The volatile components in Sarracenia flava have been analysed by GC-MS analysis and the results are given in Phytochemistry, 1975, Vol.14, pp.845-846.


Provided is a distributed and asynchronous implicit token carrier sense multiple access/collision avoidance (CSMA/CA) protocol guaranteeing quality of service for both real time and non-real time traffic. The implicit token CSMA/CA protocol allocates a band in an entire bandwidth to voice traffic and allows the remaining bands to be used for data traffic. The implicit token CSMA/CA protocol includes applying a token passing protocol to transmit voice traffic in real time by having a band in an entire bandwidth allocated using a predetermined data frame and applying a CSMA/CA mechanism to transmit data traffic in non-real time by employing remaining bands not allocated to the voice traffic using another predetermined data frame.

This application claims the priority of Korean Patent Application No. 2003-94420, filed on Dec. 22, 2003, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a communications network, and more particularly, to a protocol for a media access controller for a mobile ad-hoc network.
2. Description of the Related Art
A major challenge in a mobile ad-hoc network (MANET) is to design a media access controller (MAC) that can handle requirements for multiple media accesses to the MANET in real time. The challenge stems from the fact that the MANET does not have a stationary and centralized coordinator such as a base station and that its topology changes frequently. Further, the MAC should satisfy the needs for quality of service (QoS) in real time and for portability or mobility by being able to accommodate smaller and lighter batteries.
Conventional MACs for a wireless local area network (WLAN) usually use a carrier sense multiple access (CSMA), which is an asynchronous random access mechanism, due to its simple configuration and ease of implementation. However, due to the problem of a "hidden terminal," a multiple access with collision avoidance (MACA) protocol using a request-to-send (RTS) frame and a clear-to-send (CTS) frame was suggested.
IEEE802.11 working group developed a MAC protocol as an international standard for the MANET as well as the WLAN. The MAC protocol uses a carrier sense multiple access/collision avoidance (CSMA/CA) mechanism as a distributed coordinate function (DCF). To avoid collisions, each equipment on the WLAN monitors when the other equipment attempts to and when waits to transmit a packet. However, such a random access is not suitable for real time and periodic traffic. To complement this, polling-based real time traffic is supported by a centralized point coordinator function (PCF), which, however, is not suitable for the MANET environment that does not have a centralized coordinator. Therefore, a variety of protocols have been suggested to secure the quality of real-time traffic.
A multiple access with collision avoidance/piggyback reservation (MACA/PR) protocol is a time division multiplex (TDM) combined MAC protocol in a broad sense and uses a non-persistent CSMA mechanism for a Datagram. In this protocol, a node does not respond using the RTS and the CTS frames in its reservation table by sensing the state of a channel after a free window period. Instead, the node responds using the propagation and maintenance of reservation tables managed by neighboring nodes. Therefore, the operation of the reservation table is complicated. In addition, when a new node is added to a system, the new node should learn present reservations in a listening mode for a sufficient period of time and wait until it receives a reservation table from its neighboring nodes. Unlike a slot mechanism, an un-slot mechanism is freed from the difficulty of synchronization. However, as the provision and synchronization of a clock signal are not a problem for advanced communication systems such as a global positional system (GPS), a slotted MAC has begun to draw attention and, accordingly, diverse protocols have been suggested.
An enhanced time division multiple access (E-TDMA) protocol is reserved at a talk-spurt level. The reservation process is a five-phase procedure and takes a long time. A time division multiple access/frequency division duplex (TDMA/FDD) protocol is reserved on a call basis and not frequently used due to silence.
As described above, although a variety of slotted protocols have been suggested, these protocols additionally require the GPS or a station functioning as a centralized controller. Further, system synchronization is difficult and the operation of the protocols is complicated.

Hybrid implicit token carrier sensing multiple access/collision avoidance protocol

Electronics and Telecommunications Research Institute


A method is provided for fabricating contacts on semiconductor substrates by direct lithography that results in durable adhesion of the electrodes, increased interpixel resistance and the electrodes which act as a blocking contact, thereby providing for improved energy resolution in a resultant radiation detector.

The general requirement for room temperature operation of a semiconducting material as a nuclear detector and spectrometer is relatively large band gap energy such that thermal generation of charge carriers is kept to a minimum. Conversely, the requirement for high resolution is small band gap energy such that a large number of electron-hole pairs are created for an absorbed quantum of ionizing radiation. The material under consideration should also have a relatively high average atomic number if used in gamma ray spectroscopy to increase the gamma ray interaction probability. High charge carrier mobilities and long charge carrier lifetimes are also needed to ensure efficient charge carrier extraction and minimal effects from position-dependent charge collection. Detectors fabricated from Cadmium Zinc Telluride (CZT) meet these requirements and are used for gamma and X-ray detection. However, in addition to excellent bulk properties of the CZT single crystal, the fabrication process and structure to create the detector having electrode charge contacts is very critical to high performance of the detector device.
Metal/semiconductor contact plays an important role in determining the performance of the CZT detector device. A good metal/semiconductor contact preferably has all of the following properties, especially for a segmented detector:                a. Good adhesion.        b. Capable of preventing charge injection.        c. Capable of preventing the inclusion of "oxides" beneath the metal—an intermediate oxide layer sandwiched in between the metal and the CZT will lower the barrier height and potentially cause polarization, having a negative effect on detector performance.        d. Reliable for assembly processes, including low temperature soldering.
Heretofore these criteria have not been met in conventional CZT radiation detector technology. CdZnTe (CZT), and particularly Cd(1-x) Znx Te (where x is less than or equal to 0.5), is a wide band gap ternary II-VI compound semiconductor that, because of its unique electronic properties, is desirable for use in gamma-ray and X-ray spectrometers that operate at room temperature for nuclear radiation detection, spectroscopy and medical imaging applications. However, the performance of gamma-ray and x-ray segmented radiation detectors used in imaging applications and fabricated from CZT crystals is often limited because conventional fabrication processes do not achieve all four of the desired contact properties. Typically these devices have pixilated electrode arrays fabricated from various deposition and lithography processes with a gap between pixels, called the interpixel gap or region. Interpixel leakage currents act as a source of noise that reduces the ability of these spectrometers to resolve spectrally the unique radiological emissions from a wide variety of radioactive isotopes—i.e. the energy resolution (ER). The so-called interpixel resistance is a key limitation to performance and is typically much lower than overall device resistivity. Thus, in order to improve the spectral resolution capability of devices based on CZT crystals it is desirable to decrease interpixel leakage currents and the attendant detrimental noise effects.
It is known that for a semiconductor crystal to function effectively as a good detector material (i.e., minimizing interpixel surface leakage currents, thereby maximizing energy resolution) the crystal surfaces in the interpixel gap should have resistivity equal or higher than that of the bulk crystal. Generally, the interpixel surface quality is a function of the metal selected, deposition process and lithography process.
A small number of companies worldwide currently produce CZT detectors commercially in a variety of sizes and thicknesses. Usually one or both sides of the planar detectors are contacted with a continuous metal layer such as gold (Au) or platinum (Pt). As mentioned above, such detector substrates then need to be processed to produce a detector having a pattern of segmented contacts (e.g. pixel pads) on one surface, with the opposite surface remaining uniformly metallized. This is done so that the detector is able to produce a detector output indicating the position at which radiation impacts the detector.
It be believed that commercial pixilated or segmented CZT devices have been fabricated by the inverse lithography (or "lift off") method, with its inherent performance limitations. Also, conventional deposition and lithography processes do not effectively prevent the inclusion of "oxides" beneath the metal during the process, which has a deleterious effect on device band gap. For the specific case of CZT and gold electrodes, it is not known how to use gold contact fabrication with direct photolithography such that the resulting contacts provide good adhesion and stable excellent detector performance at the same time. Poor adhesion of metal electrodes frequently causes very serious electrode lift-off problems leading to failure of the device and limited long-term reliability. Others have found that the surface resistivity of cadmium-based substrates is degraded when the substrate is exposed to conventional metal etchants and etching processes suitable for removing gold. As a result of this, the electrical separation of the individual contacts which results from the conventional method of forming contacts is not as good as would have been expected from the bulk properties before treatment. The inverse-lithography process can be used to reduce etching damage, but has not resulted in excellent interpixel resistivity combined with adequate gold adhesion of the contacts, due to limitations of the process. An example of the inverse-lithography process is U.S. Pat. No. 6,410,922, which requires additional passivation layers to facilitate the lift-off of the interpixel gap and the electrodes to overlap the passivation material. The poor contact adhesion provided by this method makes conventional attachment by methods such as low temperature soldering difficult.
There is a need to reduce the interpixel surface leakage current in CZT crystals fabricated with metal electrodes by increasing interpixel resistance in order to improve spectral resolution. There is also a need for an enhanced contact-forming process demonstrating excellent adhesion to the CZT surface, creating an electrode that is blocking and that does not introduce oxides between the metal and CZT.
Additionally, there is a need for contact-forming processes to deposit additional electrode layers on the fabricated CZT with metal electrodes, without adversely affecting device performance or reducing the interpixel resistance further, to provide suitable contact surface for electronic read-out circuitry attachment.

Method of making segmented contacts for radiation detectors using direct photolithography