DruckWege TYPE D CASTABLE WAX Basic Model UV Resin
- Название продукта: DruckWege TYPE D CASTABLE WAX Basic Model UV Resin
- Сайт Factroy: Округ Юду, Ганьчжоу, Цзянси, Китай
- Запрос цены: admin@ascent-chem.com
- Производитель: Ascent Petrochem Holdings Co., Limited
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- DruckWege TYPE D CASTABLE WAX Basic Model UV Resin is typically used in formulations when viscosity and wax content and cure shrinkage and UV exposure dose must be controlled within specific ranges.
| Код ТН ВЭД | 561921 |
Как аккредитованный завод DruckWege TYPE D CASTABLE WAX Basic Model UV Resin, мы соблюдаем строгие протоколы качества - каждая партия подвергается строгим испытаниям для обеспечения последовательных стандартов эффективности и безопасности.
| Упаковка | DruckWege TYPE D CASTABLE WAX Basic Model UV Resin: one 1 kg light-blocking black bottle with child-resistant cap and label. |
| Погрузка контейнера (20-футовый контейнер) | 20′ FCL loading: DruckWege TYPE D CASTABLE WAX Basic Model UV Resin, palletized, secured, and documented for safe chemical transport. |
| Доставка | DruckWege TYPE D CASTABLE WAX Basic Model UV Resin ships in sealed, opaque, leak-resistant bottles with absorbent cushioning. Transport at ambient temperature, away from heat, freezing, and UV light. Consult the SDS and carrier before air, international, or expedited shipping; hazmat restrictions may apply. |
| Хранение | Store DruckWege TYPE D CASTABLE WAX Basic Model UV Resin in its original, tightly sealed, opaque container. Keep in a cool, dry, well-ventilated area at 15–25 °C, away from direct sunlight, UV light, heat, sparks, and oxidizers. Do not freeze. Keep upright to prevent leakage. Follow supplier safety data sheet and local regulations. |
| Срок годности | Unopened shelf life is typically 12 months when stored cool, dry, sealed, and protected from UV light; avoid heat and sunlight. |
Within lost-wax casting of 18 kt gold, 950 platinum, and 925 silver alloys, pattern accuracy for DruckWege TYPE D CASTABLE WAX Basic Model UV Resin is governed by cure depth, support-tip geometry, and burnout residue rather than green flexural strength alone. Published data for this specific configuration is limited; the following processing envelope is derived from class-level castable wax photopolymer bulletins and should be validated against the final alloy-investment pairing. On 405 nm DLP/LCD platforms, the resin is typically printed at 25–50 µm layer thickness, with exposure per layer adjusted to produce 0.1–0.3 mm support tips that separate cleanly from filigree sections without leaving surface craters. After green-part washing in 99% isopropanol for no more than 3–5 min, residual solvent is removed at 20–25°C under forced air for at least 30 min before investment; trapped isopropanol vapourises at approximately 82°C and can generate internal pressure sufficient to crack gypsum-bonded investment during the first ramp segment. Investment mixing under 680–720 mmHg vacuum reduces air entrapment around the pattern, and the flask is held at 20–25°C for 2 h before burnout begins. The decomposition sequence of castable wax photopolymers typically involves wax binder volatilisation at 120–180°C, acrylate network degradation at 300–450°C, and final carbon oxidation at 650–750°C. A class-level burnout profile for gold alloys uses a ramp of 2–3°C/min to 150°C, a hold of 1 h; 1.5–2°C/min to 300°C, a hold of 1 h; and 4°C/min to 750°C, a hold of 2 h, with furnace airflow maintained above 6 volume exchanges per minute. Residual ash values under such profiles are typically below 0.1% when measured by ASTM D2584-18. Flask casting temperatures in phosphate-bonded investment are 950–1,050°C for 18 kt gold, 900–1,000°C for 950 platinum, and 550–650°C for silver alloys. The most frequent production failure is not short pour but shell cracking caused by pattern expansion between 25°C and 140°C before the decomposition peak is reached.
Why Does Residual Carbon Content Matter in Dental Alloy Casting Patterns?
Residual carbon in dental alloy casting arises when the burnout hold temperature is too low, the ramp rate through 300–500°C is too steep, or the furnace atmosphere is insufficiently oxidising. For cobalt-chromium and nickel-chromium frameworks produced to ISO 22674:2016, carbon pickup can shift the alloy’s carbon concentration into a range where chromium carbide precipitates form at grain boundaries, reducing elongation after casting and increasing the incidence of brittle fracture during electrolytic polishing. Dental casting investments conforming to ISO 15912:2016 are typically phosphate-bonded and are preheated to 850–950°C for Co-Cr alloys; the pattern must decompose completely before molten alloy is introduced. A class-level burnout program for castable wax photopolymers in dental applications uses a first hold at 150°C for 1 h, a slow ramp of 1–2°C/min through 300–500°C to allow decomposition gases to escape through the investment pores, and a final hold at 750–780°C for 1–2 h under forced air. If the final hold is shortened or the furnace airflow falls below 4 air exchanges per minute, carbonaceous char can remain inside blind cavities and thin sections, producing gas porosity at the metal-interface boundary. The as-supplied resin is not marketed as a finished medical device; dental laboratory use requires validation under the applicable regulatory framework, and the final metallic framework, not the pattern resin, carries the ISO 22674:2016 mechanical and biocompatibility burden. Published data for DruckWege TYPE D Basic Model UV Resin in dental alloys is limited; therefore each dental laboratory should run a five-point fitness-for-use trial covering flask size, investment brand, and alloy grade before committing production volume.
If a castable photopolymer replaces traditional injection wax in stainless steel and nickel superalloy investment casting, the shell build sequence requires adjustment because the cured pattern does not soften uniformly during autoclave steam dewax. In conventional wax, autoclave removal at 150–180°C and 0.4–0.6 MPa leaves a clean cavity; in a photopolymer pattern, autoclave pre-removal may only plasticise the outer surface and can cause violent expansion against the primary slurry layer. Industrial foundries therefore bypass autoclave dewax and rely entirely on furnace burnout. A phosphate-bonded ceramic shell with a primary zircon or fused-silica slurry is applied in 7–9 alternating layers, with 30–45 min drying between coats at 22–24°C and 45–55% relative humidity. The total shell thickness of 6–9 mm provides green strength but also limits gas permeability; burnout ramps for stainless steel and Inconel 718 patterns are therefore held at 1–2°C/min between 150°C and 350°C, then at 3–5°C/min to 750–850°C with a 2 h hold. Pattern sections thicker than 4 mm may require an additional hold at 300°C for 2 h to prevent thermal runaway from exothermic decomposition inside the shell. The investment shell is cured at 25°C and 50% RH for 24 h after final stucco before the burn-out cycle, and the furnace is brought to 150°C before loading to avoid condensation shock. Published data for this specific configuration is limited; the ramp rates above are class-level ranges for castable photopolymers in ferrous investment casting and should be qualified with a sacrificial flight bar.
Ceramic Shell Cracking Induced by Pattern Expansion Before 140°C
The peak expansion region between 25°C and 140°C is the most critical process window for castable photopolymer patterns because the cured resin does not melt out like wax but rather expands as a viscoelastic solid until decomposition begins. Linear thermal expansion of class-level castable resins in this temperature band typically falls between 1.2% and 2.5% depending on crosslink density and filler content; under constrained shrinkage of the ceramic shell, this expansion can generate tensile strain at the inner shell surface that exceeds the green strength of the primary coat. If the shell has not dried adequately or the primary slurry was applied too thickly, through-thickness cracks appear at edges and around sprue junctions where stress concentration is highest. The failure mode is often detected only after casting as a positive fin on the metal surface, corresponding to a shell crack that filled with alloy. To control this, the first investment layer should be applied at a viscosity of 24–28 s on a Zahn #4 cup, and the second layer should not be applied until the first layer passes a thumbprint test at 20–25°C with no tack transfer. A slower ramp of 1–2°C/min from 25°C to 140°C allows the pattern to creep and transfer expansion gradually to the shell. Thermal expansion measurement by ASTM E228-17 on the pattern material and investment shell provides the quantitative basis for selecting that ramp; if the differential expansion exceeds 0.5%, a polymeric burnout additive or shell pre-conditioning at 40°C for 4 h is introduced. Published data for DruckWege TYPE D Basic Model UV Resin across shell systems is limited, so foundries should perform a triplicate shell crack test using a 10 mm × 10 mm × 40 mm pattern bar before full production.
| Alloy group | Investment type | Ramp to 150°C | Hold at 150°C | Ramp to final | Final hold | Primary risk |
|---|---|---|---|---|---|---|
| 18 kt gold | phosphate-bonded | 2–3°C/min | 1 h | 4°C/min to 750°C | 2 h | shell cracking before 140°C |
| 925 silver | gypsum-bonded | 1–2°C/min | 2 h | 2–3°C/min to 650°C | 2 h | investment burnout and residual carbon |
| Co-Cr dental | phosphate-bonded ISO 15912 | 1–2°C/min | 1–2 h | 1–2°C/min through 300–500°C, then 4°C/min to 750°C | 1–2 h | carbon pickup and carbide precipitation |
| Stainless steel | phosphate-bonded ceramic shell | 1–2°C/min | 2 h | 1–2°C/min to 350°C, then 3–5°C/min to 800°C | 2 h | shell cracking, thermal runaway in thick sections |
When a Castable Resin Pattern Replaces Wax in Turbine Blade Core Assembly
When turbine blade patterns with internal cooling passages are assembled, the castable photopolymer must be compatible with silica or alumina cores and must not contribute residues that block narrow trailing-edge channels. In production-scale nickel superalloy investment casting, pattern sections are printed in segments and joined with hot wax or adhesive; because the photopolymer surface is crosslinked and relatively non-porous, wax adhesion is lower than on traditional injection wax, requiring surface abrasion of the joint area with 400-grit silicon carbide paper or a brief 254 nm plasma treatment before adhesive application. The pattern is then assembled onto a ceramic core with a gap of 0.2–0.5 mm to allow thermal expansion of the core without transferring stress to the pattern. Burnout for cored blades in a high-velocity gas-fired furnace uses an initial ramp of 1°C/min to 150°C, a hold of 2 h to equilibrate core and pattern temperature, and a final 3°C/min ramp to 750–850°C with a hold of 3 h. The long final hold is required because the ceramic core masks portions of the pattern from oxygen, and carbon oxidation within blind feed cavities is diffusion-limited. Incomplete carbon removal can cause subsurface porosity and non-metallic inclusions in the final casting, particularly in single-crystal and directionally solidified alloys where grain boundary oxidation is not tolerated. Published data for this specific configuration is limited; a blade foundry should qualify the full burnout cycle with a ceramic core dummy assembly and inspect for core shift and residual ash.
High-Detail Micro-Casting Pattern Requirements
Micro-casting of thin-section stainless steel meshes, watch case components, and fine jewellery findings demands that the pattern resin reproduce features in the 0.2–0.5 mm range without layer delamination or surface noise. The resin is printed at 25 µm layer thickness for such components; thicker layers in the 50 µm range reduce build time but produce stair-stepping that transfers to cast surfaces and increases hand-finishing time. Uncured resin viscosity in this class at 25°C is commonly 100–250 mPa·s; this is low enough for drainage from fine features but requires sealed trays to prevent run-off during dark storage. Support structures for micro-scale patterns are limited to 0.1–0.2 mm contact tips and are placed on non-critical back surfaces, because support removal from thin sections can cause edge chipping before casting. After printing, the pattern is washed in 99% isopropanol for 2–3 min and dried for 20–30 min; extended solvent contact of more than 5 min can swell thin sections and distort the pattern geometry. A post-cure dose of 1–2 J/cm² at 365–405 nm is typical to stabilise thin walls, but overexposure embrittles the pattern and makes support removal more difficult. The investment process for micro-casting uses a 200-mesh primary stucco and a slurry viscosity of 22–26 s on a Zahn #4 cup to capture fine detail without bubbling. Burnout follows the same class-level profile as other precious metal patterns with a 150°C intermediate hold extended to 2 h for high-density clusters. Published data for DruckWege TYPE D Basic Model UV Resin in micro-casting of non-jewellery alloys is limited; pilot testing should include dimensional verification at 10× magnification after casting.
For short-cycle dental alloy casting operations, rapid burnout protocols reduce throughput time but increase the probability of carbon pickup in Co-Cr alloys. A fast cycle might reach 800°C in less than 2 h and hold for only 30 min, which is insufficient for diffusion-limited oxidation of carbon in thick sections, particularly when flasks are densely packed. Slower cycles with a 1 h hold at 150°C, a 1–2°C/min ramp through 300–500°C, and a minimum 1 h hold at 750°C reduce residual carbon but add 3–5 h to the total cycle. The economic conflict is resolved by flask-packing density: if flasks are loaded at no more than 40% of furnace chamber volume, the fast cycle can be qualified; above that density, the slow cycle is mandatory. Airflow should be maintained above 4 volume exchanges per minute during the oxidation step, and the furnace should be calibrated every 6 months with a type K thermocouple placed in the centre of a representative flask. Published data for this specific configuration is limited; each dental laboratory should map the trade-off between cycle time and residual ash for its specific furnace model and investment brand.
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- DruckWege TYPE D CASTABLE WAX Basic Model UV Resin Производится в соответствии с системой качества ISO 9001 и отвечает соответствующим нормативным требованиям.
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DruckWege TYPE D CASTABLE WAX Basic Model UV Resin is a single-component photopolymerizable wax/acrylate hybrid supplied for direct investment casting pattern production in bottom-up masked stereolithography (MSLA) and digital light processing (DLP) machines with a nominal optical output at 405 nm. The TYPE D grade is differentiated from general-purpose rigid casting resins by its wax-bearing formulation, which is intended to reduce burnout residue and moderate thermal expansion inside the ceramic shell during flask heating. The Basic Model designation refers to the entry point of the TYPE D range; it does not contain the higher particulate loading or specialized surface treatment of the advanced variants. Users should not treat the product as a thermoplastic injection wax, because pattern generation is executed photochemically and not by solidification from the melt. The resin is a non-aqueous UV-reactive mixture that must be shielded from sunlight and high-intensity ambient lighting until final cure. Conditioning to 23 °C ± 2 °C before printing stabilizes the viscosity and the dissolved oxygen cycle. Manufacturer-published lot-specific viscosity for the Basic Model is not reproduced in this document; lot acceptance should be performed by rotational viscometry under ISO 2555:2018 or with a Brookfield RV spindle at 25 °C.
Typical use geometries include jewelry filigree, dental cast frameworks, orthodontic brackets, micro-mechanical investment cast parts, and prototype patterns in low-pressure ceramic shell casting. The material is patterned in layer thicknesses between 10 µm and 200 µm, with process stability usually demonstrated in the 35 µm to 50 µm band. Thicker layers increase optical attenuation and require higher exposure dose because the dispersed wax phase scatters UV light more effectively than a clear rigid resin. Comparative evaluations against other products in the castable UV resin category should be based on measured viscosity at 25 °C, green tensile properties after post-cure under ASTM D638-14, thermogravimetric mass-loss profile under ISO 11358-1:2022, and residual ash after burnout under ISO 3451-1:2019. Traditional injection wax is evaluated by melt, congealing point, and ash tests rather than by tensile specimen testing; this difference in test methodology explains why direct comparison of materials from different classes requires a common casting trial rather than a single datasheet value.
Green-state post-cure parameters and support removal force
After printing, the pattern is considered in the green state and requires a secondary exposure before heavy handling. Post-cure systems used in production are typically UVA LED chambers or broad-spectrum fluorescent boxes with irradiance at the curing plane of 2 mW/cm² to 5 mW/cm². A starting post-cure interval of 15 min to 30 min at 23 °C is common for the castable wax resin class, but the exact dose must be determined on the user’s equipment because the resin’s wax domains attenuate light and reduce overall depth of cure relative to clear rigid resins. The post-cure chamber should not exceed 40 °C in the curing volume; excessive temperature can induce thermal drift and surface bloom of low-molecular-weight wax species. Mechanical testing of green Type D coupons is performed after conditioning at 23 °C and 50 % relative humidity under ISO 291:2008. Tensile specimens are tested under ASTM D638-14 with a crosshead speed of 5 mm/min; the resulting green-state modulus and elongation are used for internal lot comparison, not for structural design allowances.
Support removal force is a practical quality indicator. On a production MSLA bank with a 10 N load cell mounted on a peel fixture, support tips should separate cleanly without exceeding the small-section strength of the pattern. If tip removal produces white stress whitening or fractures in cuff regions, the support tip diameter is increased by 0.05 mm increments or the post-cure dose is reduced. This is an empirical machine-specific adjustment, not a material specification. Because the product is wax-bearing, large supports can be cut from the pattern using a heated blade at 70 °C; however, the heat source must not be applied directly to thin areas that are intended to retain surface detail. The use of alcohol immersion before support removal is discouraged because swelling of the wax phase can alter the apparent peel force and mimic poor support adhesion.
The investment casting burnout cycle is the primary determinant of casting success. Type D patterns undergo a two-stage mass loss in air. The first stage begins between 250 °C and 450 °C with volatilization of wax domains and photoinitiator degradation fragments; the second stage between 450 °C and 750 °C reflects oxidative decomposition of the acrylate network. Thermogravimetric characterization under ISO 11358-1:2022 with a purge gas switching sequence provides the decomposition onset, peak mass-loss rate, and final residue. A pattern lot with a narrow, high peak mass-loss rate may generate localized pressure inside the flask. Where the shell wall is below 10 mm, the ramp through the organic decomposition band is normally held between 1 °C/min and 2 °C/min. Heavier flasks with thick sections or multiple patterns require an intermediate isothermal hold at 300 °C for 60 min to 120 min and a second hold at 600 °C for 30 min to 60 min, depending on furnace load. These hold times are not product-specific values; they are operating parameters used in investment casting of photopolymer patterns and must be adapted to flask geometry.
Inadequate oxidation leaves carbonaceous residue in the cavity, which transfers to the cast metal as surface inclusions or internal porosity. The permissible terminal residue for the process is often set below 0.05 wt% by the caster after ISO 3451-1:2019 combustion. For Type D, the wax-bearing chemistry lowers the risk of thick carbon cake relative to standard non-wax castable resins, but the result is not guaranteed unless furnace oxygen supply and ramp profile are correct. The resin should be sprued so that burnout gas has a direct and short escape path to the button; blind cavities with narrow exits should be vented. Flask air change rate in an electrically heated burnout furnace is maintained at 4 to 6 chamber volumes per hour; lower air change rates can create an oxygen-limited zone at the center of a loaded furnace and produce variable residue from top to bottom. This load-dependent behavior is the main source of batch-to-batch casting variation observed on production lines using multiple flask positions.
When shell pressurization occurs during ramp segments, which process defects are observable?
Shell pressurization is detected indirectly as a crack-derived metal fin on the casting, a dull surface on the heavy section of the pattern, or an irregular button-to-sprue junction. The most common process defect is a thin, sheet-like projection extending from the pattern surface along the shell wall. This defect appears when the ceramic shell fractures under internal pressure and molten metal fills the open path. A less obvious defect is a shift in detail fidelity because the shell separates slightly at the interface with the pattern, allowing a gas film to persist until metal entry.
When such defects are observed, the first diagnostic step is to compare the TGA mass-loss curve of the current resin lot with a retained reference lot under identical ISO 11358-1:2022 conditions. If the current lot exhibits a peak mass-loss rate higher than the reference by more than 0.5 %/min or the onset shifts lower by more than 10 °C, the burnout ramp should be flattened and the supplier should be asked for lot-specific thermal data. The second step is to verify that the furnace thermocouples are located at the center of the flask load, because chamber temperature display does not equal flask interior temperature. The third step is to reduce pattern volume fraction in the flask or add a vent path. Resin substitution should be considered only after these process variables are eliminated; changing materials without changing ramp rates often transfers the defect from one geometry to another.
In comparison with standard castable photopolymers, Type D is intended to exhibit a broader decomposition envelope rather than a sharp autocatalytic decomposition spike. This attribute is not visible in the liquid state and can only be confirmed by thermal analysis. High-carbon castable resins used for engineering parts may leave a rigid char that holds shell detail but increases residue; wax-filled castable resins sacrifice some high-temperature char strength for cleaner burnout. The Type D formulation sits closer to the wax-filled end of that spectrum. Purchasers comparing products should request thermogravimetric traces acquired at the same heating rate in air, not in nitrogen alone.
Solvent immersion is not a benign cleaning step: compatibility boundaries for Type D
The uncured and green-state material is sensitive to solvent selection. Alcohol-based rinsing is used in service bureaus because it removes uncured film without immediately dissolving the wax domains. However, contact time should be limited to 3 min to 5 min in an ultrasonic bath operating at 40 kHz. Beyond that interval, the solvent migrates into the wax phase and may cause surface swelling, dimensional drift, and a loss of fine feature definition after cure. Acetone, methylene chloride, and aromatic solvents are outside the recommended cleaning envelope; they attack the acrylate matrix and can destroy the pattern before burnout. After rinsing, the pattern is dried with filtered compressed air at 0.2 MPa to 0.4 MPa and rested for 30 min to allow any retained alcohol to evaporate before investing.
Investment compatibility is process-limited. The product is used with gypsum-bonded investments in precious metal casting up to 950 °C and with phosphate-bonded investments for higher-melting alloys. Because the resin is not a wax and does not expand by melting, the pattern impression is dimensionally stable at the temperatures used for investment mixing and setting. However, vacuum mixing of the investment slurry may remove air bubbles from the pattern surface more slowly if the pattern has a high-gloss surface created by post-cure. Operators may observe an increase in retained bubble defects when switching from traditional wax because the resin surface is smoother and does not absorb the wetting agent in the same manner. A pattern-compatible wetting agent or low-foam investment addition should be evaluated using the investment manufacturer’s test method for wetting. Vat hardware compatibility includes release films, build plate coatings, and resin pumps. The Basic Model may be used in vats with fluoropolymer release films; the required film thickness, roughness, and tension are set by the printer manufacturer. Resin recirculation should avoid high-shear pumps that can destabilize the wax dispersion; peristaltic or diaphragm pumps are preferred.
Production-scale MSLA banks using Type D have shown that vat film clouding from microgel particles accelerates with high ambient temperature and frequent failed prints. The release film is replaced when surface haze reduces first-layer adhesion or when peel force rises above the machine’s threshold. Peel force can be monitored indirectly by the machine’s load cell or by operator observation of build plate deflection; a sudden increase after several thousand layers often indicates resin aging, film degradation, or partial separation in the vat.
Before a batch is released for production, the following standards are applied to the Type D material or to the casting process where indicated. The matrix below is not a supplier compliance certificate; it is an internal qualification plan for the user.
| Standard | Parameter | Application to Type D |
|---|---|---|
| ISO 2555:2018 | Viscosity by rotational viscometer | Lot acceptance and vat replenishment control at 25 °C |
| ASTM D638-14 | Tensile properties | Green-state handling resistance after post-cure |
| ISO 291:2008 | Standard conditioning atmosphere | Specimen equilibration at 23 °C, 50 % RH |
| ISO 11358-1:2022 | Thermogravimetric mass loss | Decomposition onset and peak mass-loss rate in air or nitrogen |
| ISO 3451-1:2019 | Ash residue after combustion | Burnout residue determination at 750 °C |
| REACH EC 1907/2006 | Registration and SDS documentation | Supplier documentation check for SVHC communication |
| RoHS 2011/65/EU | Restricted substance declaration | Homogeneous material disclosure for workplace control |
Batch-release records on production MSLA lines using Type D should include vat temperature, cumulative print hours, viscosity at 25 °C, and adherence of a standard test pattern. The product is stored in sealed, light-blocking containers at 15 °C to 25 °C; storage above 35 °C accelerates wax phase separation. Before each production shift, the resin is stirred slowly for 10 min with a non-aerating paddle. These controls are necessary because the wax component is a dispersion, not a dissolved solid, and its distribution changes with idle time. Filtering through a 125 µm mesh can be used to detect gel bodies; if more than 3 visible gel bodies are retained per liter, the vat should be drained, the release film inspected, and the remaining resin quarantined for viscosity testing. This operational boundary is based on observable lot stability behavior in bottom-up MSLA vats, not on a supplier-certified specification.
