48results about How to "Improve cold and heat resistance" patented technology

The invention provides a transmission belt that can suppress lowering in transmission efficiency and has improved durability. A rubber layer adhered to core wires is formed to have a durometer hardness (shore A) of not less than 72 and not more than 85, or have a tensile stress of not less than 0.5 MPa and not more than 1.7 MPa when stretched 10% in the belt longitudinal direction at 25° C., and the rubber layer is formed to have a weight increase of 90% or less after immersed in light oil for 48 hours at 25° C. or have a weight increase of 80% or less after immersed in toluene for 48 hours at 25° C. Alternatively, the rubber layer adhered to the core wires is formed to have a storage modulus of not less than 10 MPa and not more than 50 MPa and a tan δ of not more than 0.15 as measured by dynamic viscoelasticity measurement under conditions at a static load of 3 kgf / cm2, a dynamic strain of 0.4%, a frequency of 10 Hz and a temperature of 25° C. in a tensile mode in a belt longitudinal direction.

A silicone composition is disclosed. The composition includes 20-80 parts by weight of organic silicone, 2-60 parts by weight of MQ resin, 1-20 parts by weight of hydrogen-containing silicone and an effective amount of a hydrosilylation catalyst and a hydrosilylation inhibitor. The invention also discloses a preparing method of the silicone composition, a method of using the silicone composition for encapsulating electronic elements such as pressure-sensitive resistors, ceramic capacitors and thermistors, and a method of using the silicone composition for embedding electronic elements such as capacitors. The composition has a long active period, and can be stably stored for long term at 100 DEG C or below. The composition after encapsulating and embedding the electronic elements has excellent flexibility and resistance to cold and hot alternation, and has good moisture resistance and resistance to large-current impact.

The invention discloses a formula of high-voltage insulation white glaze. The high-voltage insulation white glaze mainly comprises the following raw materials in part by weight: 20 to 30 parts of potash feldspar, 20 to 30 parts of quartz powder, 8 to 15 parts of Datong soil, 6 to 12 parts of Dongsheng soil, 5 to 10 parts of wollastonite, 8 to 14 parts of forged talc, 2 to 6 parts of spodumene, 3 to 6 parts of blank and 1 to 3 parts of barium carbonate. The glaze prepared according to the formula can greatly improve the cold and heat resistance, corrosion resistance and stain resistance of porcelain, and is flat, fine and smooth in glaze surface; the bending strength of the porcelain is improved by more than 30 percent, and the glazing bending strength is more than or equal to 235 Mpa; withstand voltage is more than or equal to 35kV / mm; the volume resistance coefficient is more than or equal to 10<14> omega.cm; the dielectric coefficient (50Hz, 20 DEG C) is more than or equal to 7.5; and cold and heat rapid change resistance (temperature difference) is more than 230 DEG C. All performance indexes reach or exceed the GB8411 standard requirement.

The invention discloses a high-strength underwater structure adhesive and a preparation method thereof. The adhesive is prepared by mixing a component A and a component B according to a weight ratio of 1:1, wherein the component A comprises the following components in parts by weight: 30-48 parts of nano rubber modified epoxy resin, 50-70 parts of bisphenol A epoxy resin and 4-6 parts of thixotropic agent; the component B comprises the following components in parts by weight: 50-60 parts of underwater curing agent, 1-2 parts of accelerant, 1-3 parts of coupling agent, 2-4 parts of moistening agent, 1-2 parts of thixotropic agent and 40-80 parts of packing. Practical application shows that the high-strength underwater structure adhesive has the characteristics of complete underwater adhesion, underwater curing, high adhesion strength and short curing time, can be applied to repairing in an adhesion manner, sealing to stop leakage, and curing of various underwater buildings, and is simple in production method and process and is easy to operate.

The invention discloses a method for preparing heat and cold resisting water-soluble air-drying acrylic resin. A monometer-phase solution B is prepared from 5-15 wt% of functional monomer, 7-15 wt% of acrylic acid or methacrylic acid, 20-45 wt% of hard monomer, 8-20 wt% of hard tenacity monomer, 15-45 wt% of soft monomer, 0.3-2 wt% of organic siloxane organosilicone monomer, 0.3-2 wt% of fluorine acrylic acid monomer, and 0.5-3 wt% of double-ethylenic-bond monomer, and the total percentage of the monomers is 100%. By the adoption of the method, the heat and cold resisting water-soluble air-drying acrylic resin is provided, and the problems that existing single-component water-soluble acrylic resin paint becomes crispy under the refrigeration condition and becomes tacky and liable to contamination under heating to cause poor membrane surface scratch resistance, dryness is insufficient, and water resistance is low are solved.

The invention discloses a self-cleaning antifouling organic-inorganic super-amphiphobic polymer coating which is prepared from the following raw materials: perfluoroalkyl ethanol, methyl isobutyl ketone, HDI trimer, methyl methacrylate, styrene, hydroxyethyl methacrylate, perfluorooctyl methacrylate, benzoyl peroxide, 25-28 parts of methanol silica sol, propylene glycol methyl ether acetate, titanium dioxide, sodium hexametaphosphate, ethyl orthosilicate, vinyl triethoxysilane, an appropriate amount of ammonia water, an appropriate amount of silane coupling agent KH570, an appropriate amount of methyl hydroxyl silicone oil, an appropriate amount of 10% dibutyltin dilaurate, a dispersant, a leveling agent, a defoamer, an appropriate amount of butyl acetate, an appropriate amount of anhydrous ethanol, and an appropriate amount of deionized water. The super-amphiphobic polymer coating provided by the invention is simple and feasible in preparation method, can be firmly combined with a variety of substrates, and has universality, good self-cleaning performance, dirt resistance, scrub resistance, corrosion resistance and other performance, and good application prospects.

The invention discloses a low-temperature fast-curing epoxy resin adhesive and a preparation method thereof. The low-temperature fast-curing epoxy resin adhesive is prepared from 30%-60% of epoxy resin, 10%-20% of organic silicon resin, 6%-8.5% of modified nitrile rubber, 2%-4.5% of a catalyst, 2%-3% of a curing agent, 2%-3% of a flexibilizer, 16%-21% of inorganic filler and 2%-10% of modified filler. The inorganic filler comprises nano-montmorillonite, nano SiO2 and copper powder in the weight ratio being (5-10): (5-10): (8-11), and the modified filler comprises modified glass fiber and modified silicon carbide in the weight ratio being 7:3. The prepared epoxy resin adhesive can be used at the temperature of 30 DEG C and can be rapidly cured, the shearing strength reaches 30 MPa at the temperature of 15 DEG C, and the peeling strength reaches 8 kN / M at the temperature of 15 DEG C.

The invention discloses a process for production of high-strength pressure-resistant toughened glass. The process comprises the following steps: step 1, pretreating heat-resistant glass; step 2, delivering the pretreated heat-resistant glass to a preheating section of a toughening furnace. and preheating for 1-2h at the preheating temperature of 900-1000 DEG C; step 3, raising the temperature to 1200-1300 DEG C at the rate of 20-30 DEG C / min, and heating for 30 min; and step 4, delivering the heat-resistant glass heated in the step 3 to a quenching cooling section of the toughening furnace, and performing cooling molding to obtain a finished product of the heat-resistant toughened glass. The process for production of the high-strength pressure-resistant toughened glass can quickly heat theheat-resistant glass, can perform heat circulation through a high-temperature convection fan so as to uniformly heat the heat-resistant glass, can reduce heat energy consumption, is favorable for energy saving and emission reduction, can effectively enhance the strength, the cold and heat resistance and the impact resistance of the heat-resistant glass, and can effectively remove heat stress andresidual stress in the heat-resistant glass.

The invention provides weather-proof terrace paint as well as a preparation method thereof. The weather-proof terrace paint consists of components A and B, wherein the component A comprises the components in percentage by weight as follows: 1-30% of PUA (Polyurethane Acrylate) resin, 25-50% of hard monomer, 2-40% of soft monomer, 0.1-5% of a photosensitizer, 0% or 0.1-2% of an accelerator, 0.1-2% of a flatting agent and 0.1-2% of a deformer. The component B comprises the components in percentage by weight as follows: 1-25% of PUA resin, 5-40% of hard monomer, 2-30% of soft monomer, 2-30% of wear-resisting stuffing and 0.1-5% of a general initiator. When the paint is used, the mass proportion of the components A and B is 1:(0.8-1.5). The weather-proof terrace paint provided by the invention can be adapted for coating outdoor weather-proof and wear-resisting terraces with higher load demand, and meanwhile the coating film is extremely excellent in wear-proofness, chemical resistance and low temperature bending performance.

The invention discloses aniron-doped titanium dioxide super-amphiphobic organic and inorganic hybrid coating. The iron-doped titanium dioxidesuper-amphiphobic organic and inorganic hybrid coating is prepared from the following raw materials in parts by weight: perfluoroalkyl alcohol, methyl isobutyl ketone, an HDI trimer, methyl methacrylate, styrene, hydroxyethyl methylacrylate, perfluorooctyl methacrylate, benzoyl peroxide, methyl alcohol silica sol, propylene glycol methyl ether acetate, a proper amount of 5% ammonia water, a proper amount of methyltrimethoxysilane, a proper amount of methyl-ethyloxy silicone oil, a proper amount of 10% dibutyltin dilaurate, a dispersing agent, a flatting agent, an antifoaming agent, a proper amount of butyl acetate, titanium tetrachloride, a proper amount of ferric trichloride hexahydrate and a proper amount of deionized water. The prepared iron-doped titanium dioxidesuper-amphiphobic coating is simple in preparation technology, low in cost, wide in raw material source, good in coating hardness, not easy to wear and high in adhesive force, has super-hydrophobic property, oleophobic property, antibacterial property, wear resistance and corrosion resistance, and is excellent in performance and worthy of popularization.

The invention discloses a microbial fertilizer for activating soil fertility. The microbial fertilizer is prepared from the following raw materials (by weight): 50-52 parts of fungus chaff, 6-7 parts of peanut vine, 5-6 parts of meerschaum powder, 10-11 parts of turfy soil, 5-6 parts of fish meal, 25-30 parts of attapulgite, 5-5.5 parts of azotobacter chroococcum, 70-72 parts of a phosphate buffer with pH7.0, 5-6 parts of sodium alginate, 4-5 parts of calcium chloride and 2-3 parts of chitosan. According to the application, fungus chaff is used as a microbial carrier, and more organic matters are provided for growth of strains. After fungus chaff is puffed, water absorption of the microbial fertilizer is raised, and a moist living environment is provided for microbes. By embedding of sodium alginate, salt tolerance, acid-base resistance, cold and heat resistance and drug resistance of microbes can be enhanced. By coating with chitosan, low mechanical strength of sodium alginate is overcome. In addition, the added turfy soil and the like can improve soil and activate soil fertility.

The invention discloses a humic acid-microorganism composite fertilizer. The humic acid-microorganism composite fertilizer is prepared from the following raw materials in parts by weight: 50-52 parts of mushroom bran, 2-3 parts of humic acid, 4-5 parts of pomace, 4-5 parts of peanut meal, 8-9 parts of volcanic ash, 4-5 parts of sea-foam stone powder, 25-30 parts of attapulgite, 5-5.5 parts of azotobacter chroococcum, 70-72 parts of phosphate buffer solution with pH of 7.0, 5-6 parts of sodium alginate, 4-5 parts of calcium chloride and 2-3 parts of chitosan. The mushroom bran is taken as a microbial carrier, so that more organic matters are provided for strain growth; after the mushroom bran is puffed, the hydroscopicity is enhanced, and a wet living environment is provided for microorganisms; the sodium alginate is adopted for embedding, so that the salt tolerance, acid and alkali tolerance, cold and heat tolerance and drug tolerance of the microorganisms can be enhanced; the chitosan is used for enveloping, so that the defect of low mechanical strength of the sodium alginate is overcome; moreover, through the added humic acid, the soil can be improved, and the crop growth is simulated.

The invention relates to a wolfram rod and quartz direct sealing-type super high pressure capillary mercury lamp in the field of electron vacuum. It can effectively avert the lamp frying and gas leakage. It changes the traditional transition attended mode which adds molybdenum and platinum between the electrode and the lead wire.

The invention discloses a building fence material prepared from a steel core composite PVC material. Weight part, the composition comprises the following components, the material comprises the following components in parts by weight: 70-85 parts of PVC resin particles, 5-15 parts of polyvinyl chloride, 5-15 parts of phenolic resin particles, 0.1-0.5 part of p-phenylenediamine, 0.1-0.5 part of barium-zinc composite salt, 1-5 parts of a foaming agent, 0.5-3 parts of a filling agent, 0.1-0.5 part of titanium dioxide and 0.1-0.5 part of an antistatic agent. The flame retardance, wind pressure resistance, heat resistance, freezing resistance and the like of the fence material are enhanced, and weathering and oxidation are avoided.

The invention discloses a photoelectric positioner for a transport manipulator. The photoelectric positioner for the transport manipulator comprises a transport manipulator body, a fixing seat, a rotating shaft, a first rotating arm, a photoelectric positioning mechanism, a second rotating arm, a transmission piece and a manipulator. The transport manipulator body comprises the fixing seat, the rotating shaft and the first rotating arm. A first photoelectric sensor and a second photoelectric sensor are correspondingly mounted on the surfaces of the X axis and the Y axis of the transport manipulator body,the change of light sources can be measured in real time, andmeasured signals are transmitted to a micro processer after being treated by a signal receiver; the signals are transmitted to adisplay screen by a signal projector after being transferred and treated by the micro processer; finally, related operationis performed by the staff through controlling function keys. Data transmission between the signal projector and the display screen is carried out through wirelessradio frequency signals so that position information of the transport manipulator can be collected rapidly and circuit connection between the signal projector and the display screen is omitted; the information transmission is convenient and the using effect is good.

The invention discloses a nano-ceramic imitation coating. The raw materials for its preparation are composed of the following components by weight percentage: 35-39 parts of nano-titanium dioxide, 33-48 parts of nano-calcium oxide powder, 25-35 parts of acrylic adhesive, and 5-35 parts of citric acid. 8 parts, 9~12 parts of dioctyl phthalate, 1~2 parts of nano-aluminum silicate powder, 2~5 parts of lignin, 0.1~0.2 parts of ethylenediamine, 0.2~0.5 parts of polyaluminum chloride, Foam agent 0.2~0.4 parts, water 50~80 parts. Compared with the prior art, the nano-ceramic imitation paint provided by the invention is greatly enhanced in cold and heat resistance, salt spray resistance, water resistance and human aging.

A low-expansion glass-ceramics tableware is composed of the following ingredients (by weight): 51.5-64% of SiO2, 6.8-11% of P2O5, 3-5.2% of Li2O, 0.5-2.2% of MgO, 0.4-2.1% of ZnO, 0.2-2.5% of CaO, 0.5-4.5% of BaO, 0.2-3% of SrO, 0.6-2% of Sb2O3, Al2O3, TiO2 and ZrO2, wherein the total weight percentage of Al2O3 and SiO2 is 75-84%, and the total weight percentage of TiO2 and ZrO2 is 3.5-5%. As heat treatment temperature and time of glass tableware are accurately controlled, thermal stress and residual stress in glass tableware are effectively removed, mechanical strength, hot-cold resistance and impact resistance of glass tableware are raised, and self-explosion phenomenon of glass tableware is effectively solved.

The invention discloses a preparation method of ceramic artware. The method comprises the following steps that colorant preparation is performed; 2, glaze preparation is performed: 10 to 16 percent ofcolorants and 84 to 90 percent of lime glaze obtained in the first step are weighed; the colorants and the colorants are diluted and are uniformly mixed to pass through a 500-mesh sieve; glaze is obtained; 3, the ceramic artware subjected to biscuit firing is soaked for 1 to 2h in soaking liquid; after natural air drying, the soaked ceramic artware is put into a refrigeration house being -10 to -20 DEG C to be frozen for 8 to 12h; after being taken out, the ceramic artware is placed at room temperature for 12 to 16h; then, glazing is performed; the glazed ceramic artware enters a kiln; calcination is performed at the temperature of 1000 to 1200 DEG C; the ceramic artwork is obtained; the soaking liquid is a medical stone water solution; the prepared artware has bright color and uniform color luster; after being used for a long time, the ceramic artware is beneficial for the human body.

The invention discloses a wear-resistant communication cable sheathing material. The wear-resistant communication cable sheath comprises the following components calculated in parts by mass: 20 to 40parts of chlorosulfonated polyethylene, 10 to 30 parts of polyethylene glycol, 4 to 12 parts of carbon black, 2 to 4 parts of an MBS-grafted maleic anhydride copolymer, 0.6 to 1.0 part of an antioxidant, 0.2 to 0.8 part of zinc stearate and 10 to 20 parts of a flame retardant. The prepared cable sheath is wear-resistant and crack-resistant, simple in preparation method and convenient to operate.

The invention discloses a low-temperature fast-curing epoxy resin adhesive and a preparation method thereof. The low-temperature fast-curing epoxy resin adhesive is prepared from 30%-60% of epoxy resin, 10%-20% of organic silicon resin, 6%-8.5% of modified nitrile rubber, 2%-4.5% of a catalyst, 2%-3% of a curing agent, 2%-3% of a flexibilizer, 16%-21% of inorganic filler and 2%-10% of modified filler. The inorganic filler comprises nano-montmorillonite, nano SiO2 and copper powder in the weight ratio being (5-10): (5-10): (8-11), and the modified filler comprises modified glass fiber and modified silicon carbide in the weight ratio being 7:3. The prepared epoxy resin adhesive can be used at the temperature of 30 DEG C and can be rapidly cured, the shearing strength reaches 30 MPa at the temperature of 15 DEG C, and the peeling strength reaches 8 kN / M at the temperature of 15 DEG C.

The invention provides a concrete decorating plate and a preparation method thereof. The concrete decorating plate comprises a concrete structure layer, an interface layer and a decorating layer. Raw materials of the concrete structure layer comprise ultrahigh strength concrete and phase change and energy storage particles, and the mass ratio of the phase change and energy storage particles to the ultrahigh strength concrete is 2%-10%; the interface layer is of a net-shaped structure and is arranged on the concrete structure layer; the decorating layer is arranged on the interface layer and the concrete structure layer, and raw materials of the decorating layer comprise, by weight, 300-550 parts of cement, 700-950 parts of 20-40-mesh quartz sand, 240-310 parts of 40-70-mesh quartz sand, 15-22 parts of a water reducing agent, 0.1-0.7 part of cellulose ether and 190-240 parts of water. According to the concrete decorating plate, the concrete structure, the interface layer and the decorating layer matched with the concrete structure layer and the interface layer are adopted, the strength of the concrete decorating plate is improved, and then the thickness of the concrete decorating plate is decreased; the phase change and energy storage particles are added into concrete, phase change heat absorption or heat release is generated by the phase change and energy storage particles, the cold and heat resistance of the concrete decorating plate is improved, an environment temperature adjusting effect is achieved, and then the durability of the concrete decorating plate is improved.

The invention discloses a thermal-insulated hybrid coating containing waste polystyrene foam plastic. The coating is prepared from raw materials as follows: perfluoroalkyl alcohol, methyl isobutyl ketone, HDI tripolymer, methyl methacrylate, styrene, hydroxyethyl methacrylate, tridecafluorooctyl methacrylate, benzoyl peroxide, methanol silica sol, propylene glycol methyl ether acetate, waste polystyrene, maleic anhydride, hexadecyl trimethyl ammonium chloride, an emulsifier OP-10, rosin, ferrite powder, a proper amount of 5% ammonia water, a proper amount of mercaptoalkylalkoxysilane, a proper amount of dimethyl silicone, a proper amount of 10% dibutyl tin dilaurate, a dispersant, a flatting agent, a defoaming agent, a proper amount of butyl acetate, a proper amount of 20% alkali liquor, ethyl acetate, a proper amount of dichloromethane, a proper amount of acetone and a proper amount of deionized water. The prepared coating has good hydrophobic and oleophobic effects, good thermal-insulated effects and high adhesion, is simple in preparation process and has better practical application prospects.

The invention discloses tire burst-proof rubber. The tire burst-proof rubber comprises the following components in percentage by mass: 20-35% of a main polymer, 30-60% of tackifying resin, 10-25% of a diluting agent and 0.2-0.5% of an additive, and a special polystyrene-isoprene-styrene block copolymer is used as a main raw material. Through grafting modification, the rubber has 10 or more branched chains, and has efficient attaching performance, and through a special tackifier, cold resistance and heat resistance are improved, and a burst-proof function is effectively realized.

The composition of regeneratino source of lead-acid battery contains (wt%) 1-4% of phosphoric acid, 1.5-8% of calcium phosphate, 0.5-4% of carbonic acid, 6-26% of tartaric acid, 3-5% of EOTA, 8-16% of cadmium sulfate, 8-12% of magnesium sulfate, 10-20% of aluminium sulfate, 4-6% of calcium and 15-25% of distilled water. The above-mentioned raw materials are proportioned and added in the distilledwater, stirred for 65-70 min., dissolved to obtain liquid finished product, stored for 20 days, and can be used. Said invention can prolong service life of battery.

The purpose of the present invention is to provide a novel compound which is useful as a plasticizer that has improved heat resistance and cold resistance, while having good inherent plasticization performance as a plasticizer, or which is useful as a stabilizer for chlorine-containing resins. The inventors have found that a novel epoxycyclohexane dicarboxylic acid diester having a specific structure, which has an epoxy group in the molecular structure and has improved cold resistance and heat resistance, enables the achievement of the above-described purpose, and have been able to achieve a novel compound that is useful as a plasticizer and as a stabilizer.

The invention discloses a high-nutrient microbial fertilizer. The high-nutrient microbial fertilizer is prepared from, by weight, 50 to 52 parts of mushroom bran, 5 to 6 parts of traditional Chinese medicinal material residue, 6 to 7 parts of soya bean meal, 4 to 5 parts of herba sphagni, 5 to 6 parts of sugar residue, 5 to 6 parts of caragana korshinskii powder, 25 to 30 parts of attapulgite, 5 to 5.5 parts of azotobacter chroococcum, 70 to 72 parts of a phosphate buffer with a pH value of 7.0, 5 to 6 parts of sodium alginate, 4 to 5 parts of calcium chloride, and 2 to 3 parts of chitosan. According to the invention, mushroom bran is taken as a microorganism carrier, and more organic matters are provided for growth of bacteria; water absorbing quality is improved via puffing of mushroom bran, and a moist living environment is provided for microorganisms; embedding with sodium alginate is capable of improving salt tolerance, acid and alkali resistance, cold and hot resistance, and drug resistance of microorganisms; and a problem that the mechanical strength of sodium alginate is poor is solved via coating with chitosan; and the high-nutrient microbial fertilizer is high in nutrient content, and is capable of increasing crop yield.

The invention discloses an impact-erosion resistant marine concrete dual-ash gelling powder and a preparation method and device thereof, and belongs to the field of gelling materials. The dual-ash gelling powder comprises following raw materials in parts by weight: 30 to 40 parts of cement, 15 to 25 parts of furnace steel ash, 12 to 20 parts of slag, 15 to 18 parts of silica fume, 2 to 5 parts ofexpanded graphite, 2 to 5 parts of ceramic micro powder, and 5 to 12 parts of rubber powder. The preparation method comprises following steps: preparing raw materials; preparing a basic material; andpreparing the dual-ash gelling powder. The problem that in the prior art, the impact-erosion resistant performance of conventional marine concrete is bad is solved.

The invention discloses a preparation method of a mould proof ceramic artwork. The method comprises the following steps: 1) preparing a colorant; 2) preparing a glaze, namely, weighing 10-16% of the colorant obtained in step 1), and 84-90% of lime glaze; diluting and uniformly mixing the colorant and the lime glaze; then sieving through 500 meshes to obtain the glaze; 3) soaking the biscuited ceramic artwork in a soaking solution for 1-2h; naturally drying by air; freezing in a freezing warehouse under the temperature of -10 to 20 DEG C for 8-12h; moving out; and standing under normal temperature for 12-16h; glazing; and roasting through a kiln under the temperature of 1000-1200 DEG C to obtain the ceramic artwork. The prepared artwork is bright in color, hard to mould, uniform in color, and good to human health after long-term use, and is particularly used in humid coastal regions.

The invention relates to varnish for an epoxy casting transformer. The varnish is prepared by the following materials in parts by weight: 15-20 parts of methacrylate, 20-25 parts of shellac, 25-30 parts of polyamide resin, 15-25 parts of o-hydroxy phenyl benzoate, 15-20 parts of propanediol butyl ether, 5-10 parts of lecithin, 10-15 parts of fluorocarbon resin, 1-3 parts of hydroxymethyl cellulose, 1-5 parts of polyoxypropylene glycerol ether and 5-8 parts of zinc oxide powder. The varnish provided by the invention is corrosion-resistant, illumination-resistant, cold-resistant and heat-resistant, has more stable properties than common coatings on the market, and has promotion value.