A transparent silicone rubber material for dental impression and its preparation method and application
Transparent silicone rubber materials were prepared by using a specific ratio of materials and catalysts, which solved the problems of opacity, poor mechanical properties, and difficulty in controlling curing time in dental impression materials. This resulted in high transparency, excellent mechanical properties, and moderate curing time, ensuring biosafety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 中国人民解放军总医院第八医学中心
- Filing Date
- 2026-03-20
- Publication Date
- 2026-06-12
AI Technical Summary
Existing dental impression materials suffer from problems such as opacity, poor mechanical properties, difficulty in controlling curing time, and insufficient biological stability.
Transparent silicone rubber material was prepared by using a specific ratio of vinyl-terminated polydimethylsiloxane, benzyl silicone oil, nano silica, methyltriethoxysilane and polyether-modified polysiloxane as base materials, combined with hydrogen-containing silicone oil, platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 1-ethynyl-1-cyclohexanol and cerium oxide as catalysts, through mixing and ultrasonic treatment.
The prepared transparent silicone rubber material has high transparency, excellent mechanical properties and moderate curing time, ensuring the convenience of clinical operation and biosafety.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of impression material technology, and in particular to a transparent silicone rubber material for dental impressions, its preparation method, and its application. Background Technology
[0002] Dental impression materials, as commonly used materials in prosthodontics, need to meet the requirements of high precision, good biocompatibility, and ease of operation. With the continuous improvement of prosthodontists' requirements for material performance and treatment standards, traditional silicone rubber impression materials, although having good dimensional stability, still have the following limitations: (1) Opacity: Due to uneven dispersion of fillers or differences in refractive index, existing materials affect the doctor's ability to visualize the details of the impression; (2) Limited mechanical properties: Conventional silicone rubber is difficult to balance between tear resistance and flexibility, which can easily lead to deformation or breakage during impression taking; (3) Defects in curing control: The platinum catalytic system is easily affected by the concentration of inhibitors, resulting in a low match between operation time and curing time; (4) Poor biostability: It is prone to yellowing or performance degradation during long-term storage, affecting the accuracy of the impression.
[0003] In recent years, although nano-silica modified materials have been able to improve mechanical strength, their dispersibility in the matrix remains a technical challenge. Furthermore, while the application of phenyl silicone oil can adjust the refractive index, excessive addition can lead to increased viscosity, which is detrimental to clinical procedures.
[0004] Therefore, it is of great significance to study a transparent silicone rubber material for dental impressions that combines high transparency, controllable curing properties, and excellent mechanical properties, as well as its preparation method and application. Summary of the Invention
[0005] The purpose of this invention is to provide a transparent silicone rubber material for dental impressions, its preparation method and application, thereby solving the problems of opacity, poor mechanical properties, excessive curing time leading to sticky residue, or excessive curing time resulting in insufficient operation time in the prior art.
[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a transparent silicone rubber material for dental impressions, the transparent silicone rubber material being composed of a base material and a catalyst, wherein the mass ratio of the base material to the catalyst is 7~8:1; The substrate material comprises the following components in parts by weight: 100 parts vinyl-terminated polydimethylsiloxane, 8-12 parts benzyl silicone oil, 4-6 parts nano silica, 3-5 parts methyltriethoxysilane and 3-5 parts polyether-modified polysiloxane. The catalyst comprises the following components in parts by weight: 10-15 parts of hydrogen-containing silicone oil, 0.2-0.4 parts of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 0.05-0.1 parts of 1-ethynyl-1-cyclohexanol, and 0.5-1 parts of cerium oxide.
[0007] Preferably, the viscosity of the vinyl-terminated polydimethylsiloxane is 18000~22000 mPa·s, and the particle size of the nano-silica is 10~15 nm.
[0008] Preferably, the cerium oxide has a particle size of 20-50 nm.
[0009] The present invention also provides a method for preparing a transparent silicone rubber material for dental impressions, comprising the following steps: 1) A base material is obtained by mixing vinyl-terminated polydimethylsiloxane, benzyl silicone oil, nano silica, methyltriethoxysilane and polyether-modified polysiloxane; 2) A catalyst was obtained by mixing hydrogen-containing silicone oil, platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 1-ethynyl-1-cyclohexanol and cerium oxide; 3) The substrate material is mixed with the catalyst to obtain a transparent silicone rubber material.
[0010] Preferably, in step 1), the mixing is carried out under a protective atmosphere, which is nitrogen.
[0011] Preferably, in step 1), the mixing speed is 800~2500 rpm, the mixing temperature is 20~30℃, and the mixing time is 45~60 min.
[0012] Preferably, in step 2), the mixing is ultrasonic mixing, the ultrasonic mixing frequency is 35~40kHz, and the ultrasonic mixing time is 13~18min.
[0013] Preferably, in step 2), the ultrasonic mixing is performed under light-protected conditions.
[0014] Preferably, in step 3), the mixing time is 15-25 seconds and the mixing temperature is 20-30°C.
[0015] The present invention also provides the application of the aforementioned transparent silicone rubber material for dental impressions in dental impressions.
[0016] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects: The transparent silicone rubber material obtained by this invention has excellent transparency, with a light transmittance of more than 90%, an elastic modulus of up to 1.41 MPa, a room temperature compression ratio as low as 1.81%, and a moderate curing time, which ensures clinical operation time while shortening curing time to a certain extent. The biosafety of the material also meets the standards. Detailed Implementation
[0017] This invention provides a transparent silicone rubber material for dental impressions, the transparent silicone rubber material being composed of a base material and a catalyst, wherein the mass ratio of the base material to the catalyst is 7~8:1; The substrate material comprises the following components in parts by weight: 100 parts vinyl-terminated polydimethylsiloxane, 8-12 parts benzyl silicone oil, 4-6 parts nano silica, 3-5 parts methyltriethoxysilane and 3-5 parts polyether-modified polysiloxane. The catalyst comprises the following components in parts by weight: 10-15 parts of hydrogen-containing silicone oil, 0.2-0.4 parts of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 0.05-0.1 parts of 1-ethynyl-1-cyclohexanol, and 0.5-1 parts of cerium oxide.
[0018] In this invention, the mass ratio of the substrate material to the catalyst is preferably 7.2~7.8:1, more preferably 7.3~7.7:1, and even more preferably 7.5~7.6:1.
[0019] In this invention, the preferred mass fraction of the benzyl silicone oil is 9-11 parts, more preferably 10 parts; the preferred mass fraction of the nano-silica is 4.5-5.5 parts, more preferably 5 parts; the preferred mass fraction of the methyltriethoxysilane is 3.5-4.5 parts, more preferably 4 parts; the preferred mass fraction of the polyether-modified polysiloxane is 3.5-4.5 parts, more preferably 4 parts; the preferred mass fraction of the hydrogen-containing silicone oil is 11-14 parts, more preferably 12-13 parts; the preferred mass fraction of the platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane is 0.25-0.35 parts, more preferably 0.3 parts; the preferred mass fraction of the 1-ethynyl-1-cyclohexanol is 0.06-0.09 parts, more preferably 0.07-0.08 parts; and the preferred mass fraction of the cerium oxide is 0.6-0.9 parts, more preferably 0.7-0.8 parts.
[0020] In this invention, the viscosity of the vinyl-terminated polydimethylsiloxane is preferably 18000~22000 mPa·s, more preferably 19000~21000 mPa·s, and even more preferably 20000 mPa·s. The particle size of the nano-silica is preferably 10~15 nm, more preferably 11~14 nm, and even more preferably 12~13 nm.
[0021] In this invention, the particle size of the cerium oxide is preferably 20-50 nm, more preferably 25-45 nm, and even more preferably 30-40 nm.
[0022] In this invention, the hydrogen content of the hydrogen-containing silicone oil is preferably 12-17 wt%, more preferably 13-16 wt%, and even more preferably 14-15 wt%; this hydrogen content can ensure a moderate crosslinking density and guarantee that the obtained silicone rubber material has a good elastic modulus.
[0023] In this invention, the vinyl-terminated polydimethylsiloxane serves as the basic polymer skeleton, providing the main structure for the transparent silicone rubber material. The viscosity control ensures the mechanical strength of the transparent silicone rubber material while giving it a certain degree of fluidity. The vinyl groups in the vinyl-terminated polydimethylsiloxane undergo an addition reaction with platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane to form a three-dimensional cross-linked network structure.
[0024] In this invention, the benzyl silicone oil is matched with vinyl-terminated polydimethylsiloxane to synergistically reduce light scattering, achieve high transparency, and improve the flexibility of the material.
[0025] In this invention, the nano-silica forms hydrogen bonds between the hydroxyl groups on its surface and the vinyl-terminated polydimethylsiloxane, thereby improving the tear resistance of the silicone rubber material while maintaining high light transmittance.
[0026] In this invention, the addition of methyltriethoxysilane can promote the interfacial bonding between nano-silica and vinyl-terminated polydimethylsiloxane, and at the same time assist cross-linking.
[0027] In this invention, the polyether-modified polysiloxane can improve the compatibility of each component and prevent filler sedimentation.
[0028] In this invention, the synergistic effect between platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane and 1-ethynyl-1-cyclohexanol can delay the reaction initiation time and avoid premature curing during clinical operations; when the amount of 1-ethynyl-1-cyclohexanol added is greater than 0.1 parts, it will lead to incomplete curing and thus cause sticky residue.
[0029] In this invention, the addition of cerium oxide can compensate for the optical deviation of benzyl silicone oil and improve the uniformity of light transmission.
[0030] The present invention also provides a method for preparing a transparent silicone rubber material for dental impressions, comprising the following steps: 1) A base material is obtained by mixing vinyl-terminated polydimethylsiloxane, benzyl silicone oil, nano silica, methyltriethoxysilane and polyether-modified polysiloxane; 2) A catalyst was obtained by mixing hydrogen-containing silicone oil, platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 1-ethynyl-1-cyclohexanol and cerium oxide; 3) The substrate material is mixed with the catalyst to obtain a transparent silicone rubber material.
[0031] In this invention, in step 1), the mixing is preferably carried out under a protective atmosphere, preferably nitrogen.
[0032] In this invention, in step 1), the mixing speed is preferably 800~2500 rpm, more preferably 1000~2000 rpm, and even more preferably 1200~1800 rpm; the mixing temperature is preferably 20~30℃, more preferably 22~28℃, and even more preferably 23~25℃; and the mixing time is preferably 45~60 min, more preferably 50~58 min, and even more preferably 55~56 min.
[0033] In this invention, the mixing step in step 1) is preferably as follows: under a protective atmosphere, vinyl-terminated polydimethylsiloxane and benzyl silicone oil are mixed once, then nano-silica is added in equal amounts in three portions, and then methyltriethoxysilane and polyether-modified polysiloxane are added for a second mixing, thus completing the mixing. The preferred mixing speed for a single mixing cycle is 1800~2500 rpm, more preferably 1900~2400 rpm, and even more preferably 2000~2200 rpm. The preferred mixing time for a single mixing cycle is 7~10 min, and even more preferably 8~9 min. In the process of adding nano-silica in equal amounts in three separate additions, stirring is performed after each addition. The stirring speed is preferably 1200~1500 rpm, more preferably 1250~1450 rpm, and even more preferably 1300~1400 rpm. The stirring time is preferably 7~10 min, and even more preferably 8~9 min. The preferred rotation speed for the secondary mixing is 800-1200 rpm, more preferably 900-1100 rpm, and even more preferably 1000-1050 rpm. The preferred mixing time is 16-20 min, more preferably 17-19 min, and even more preferably 18 min.
[0034] In this invention, in step 2), the mixing is preferably ultrasonic mixing, the ultrasonic mixing frequency is preferably 35~40kHz, more preferably 36~39kHz, more preferably 37~38kHz, and the ultrasonic mixing time is preferably 13~18min, more preferably 14~17min, and more preferably 15~16min.
[0035] In this invention, in step 2), ultrasonic mixing is preferably performed under light-protected conditions.
[0036] In this invention, in step 2), the mixing is preferably performed by first ultrasonically mixing the hydrogen-containing silicone oil and platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, and then by adding 1-ethynyl-1-cyclohexanol and cerium oxide for a second ultrasonic mixing. The preferred time for the first ultrasonic mixing is 10-13 min, more preferably 11-12 min; the preferred time for the second ultrasonic mixing is 3-5 min, more preferably 4 min; the preferred frequencies for the first and second ultrasonic mixing are 35-40 kHz, more preferably 36-39 kHz, and even more preferably 37-38 kHz.
[0037] In this invention, in step 3), the mixing time is preferably 15-25s, more preferably 17-23s, and even more preferably 20-22s, and the mixing temperature is preferably 20-30℃, more preferably 22-28℃, and even more preferably 23-25℃.
[0038] The present invention also provides the application of the aforementioned transparent silicone rubber material for dental impressions in dental impressions.
[0039] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0040] Example 1
[0041] The raw materials and their mass fractions for preparing the transparent silicone rubber material described in this embodiment are as follows: Base material: 100 parts vinyl-terminated polydimethylsiloxane with a viscosity of 20000 mPa·s, 10 parts benzyl silicone oil, 5 parts nano-silica with a particle size of 12 nm, 4 parts methyltriethoxysilane and 4 parts polyether-modified polysiloxane. Catalyst: 13 parts of hydrogen-containing silicone oil with a hydrogen content of 15 wt%, 0.3 parts of platinum (0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 0.08 parts of 1-ethynyl-1-cyclohexanol and 0.6 parts of cerium oxide with a particle size of 30 nm; The preparation steps of the transparent silicone rubber material are as follows: Under a nitrogen atmosphere and at a temperature of 25°C, vinyl-terminated polydimethylsiloxane and benzyl silicone oil were mixed at 2400 rpm for 8 min. Then, nano-silica was added in three equal parts, and each addition was mixed at 1400 rpm for 10 min. Finally, methyltriethoxysilane and polyether-modified polysiloxane were added and mixed at 800 rpm for 18 min to obtain the substrate material. Under light-protected conditions, hydrogen-containing silicone oil and platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane were ultrasonically mixed at a frequency of 38 kHz for 10 min, and then 1-ethynyl-1-cyclohexanol and cerium oxide were added and ultrasonically mixed at a frequency of 38 kHz for 4 min to obtain the catalyst. The substrate material and the catalyst were mixed at a mass ratio of 7.5:1 at 25°C for 20 seconds to obtain a transparent silicone rubber material.
[0042] Example 2
[0043] The raw materials and their mass fractions in Example 1 were replaced with "Base material: 100 parts of vinyl-terminated polydimethylsiloxane with a viscosity of 21000 mPa·s, 8 parts of benzyl silicone oil, 4 parts of nano-silica with a particle size of 13 nm, 3 parts of methyltriethoxysilane and 3 parts of polyether-modified polysiloxane; Catalyst: 11 parts of hydrogen-containing silicone oil with a hydrogen content of 14 wt%, 0.25 parts of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 0.05 parts of 1-ethynyl-1-cyclohexanol and 0.5 parts of cerium oxide with a particle size of 20 nm", and the other steps were the same as in Example 1, to obtain a transparent silicone rubber material.
[0044] Example 3
[0045] The raw materials and their mass fractions in Example 1 were replaced with "Base material: 100 parts of vinyl-terminated polydimethylsiloxane with a viscosity of 20000 mPa·s, 12 parts of benzyl silicone oil, 6 parts of nano-silica with a particle size of 10 nm, 5 parts of methyltriethoxysilane and 5 parts of polyether-modified polysiloxane; Catalyst: 14 parts of hydrogen-containing silicone oil with a hydrogen content of 16 wt%, 0.25 parts of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 0.08 parts of 1-ethynyl-1-cyclohexanol and 0.8 parts of cerium oxide with a particle size of 25 nm", and the other steps were the same as in Example 1, to obtain a transparent silicone rubber material.
[0046] Example 4
[0047] The catalyst preparation in Example 1 was replaced by "under light-protected conditions, hydrogen-containing silicone oil and platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane were ultrasonically mixed at a frequency of 35 kHz for 13 min, and then 1-ethynyl-1-cyclohexanol and cerium oxide were added and ultrasonically mixed at a frequency of 39 kHz for 3 min to obtain the catalyst". Other steps were the same as in Example 1, and a transparent silicone rubber material was obtained.
[0048] Example 5
[0049] Replace "the mass ratio of the substrate material to the catalyst is 7.5:1" in Example 1 with "the mass ratio of the substrate material to the catalyst is 7:1", and follow the same steps as in Example 1 to obtain a transparent silicone rubber material.
[0050] Comparative Example 1
[0051] Replace “0.08 parts 1-ethynyl-1-cyclohexanol” in Example 1 with “0.15 parts 1-ethynyl-1-cyclohexanol”, and follow the same steps as in Example 1 to obtain a transparent silicone rubber material.
[0052] Comparative Example 2
[0053] Replace "14 parts of hydrogen-containing silicone oil with a hydrogen content of 16 wt%" in Example 1 with "14 parts of hydrogen-containing silicone oil with a hydrogen content of 20 wt%", and follow the same steps as in Example 1 to obtain a transparent silicone rubber material.
[0054] Comparative Example 3
[0055] The benzyl silicone oil in Example 1 was removed, and the other steps were the same as in Example 1, to obtain a transparent silicone rubber material.
[0056] Comparative Example 4
[0057] Replace "0.6 parts of cerium oxide with a particle size of 30 nm" in Example 1 with "0.6 parts of titanium dioxide with a particle size of 30 nm", and follow the same steps as in Example 1 to obtain a transparent silicone rubber material.
[0058] Comparative Example 5
[0059] The platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane in Example 1 was removed, and the other steps were the same as in Example 1, to obtain a transparent silicone rubber material.
[0060] The transparent silicone rubber materials obtained in Examples 1-5 and Comparative Examples 1-5 were subjected to the following performance tests, and the test results are shown in Table 1.
[0061] Transmittance testing: The test was conducted in accordance with the national standard GB / T 2410-2008 "Determination of transmittance and haze of transparent plastics"; Elastic modulus testing: The test was conducted in accordance with the national standard GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber"; Room temperature compression ratio test: The test is conducted in accordance with the national standard GB / T 7759-2015 "Determination of compression set of vulcanized rubber or thermoplastic rubber"; Curing time: Tested according to international standard: ISO 4823:2021 "Dental elastic impressions and occlusal positioning materials"; Cytotoxicity testing: The testing was conducted in accordance with the national standard GB / T 16886.5-2017 "Biological Evaluation of Medical Devices".
[0062] Table 1. Performance test results of the transparent silicone rubber materials obtained in Examples 1-5 and Comparative Examples 1-5
[0063] As shown in Table 1, the transparent silicone rubber material obtained by this invention has excellent transparency, with a light transmittance of more than 90%, an elastic modulus of up to 1.41 MPa, a room temperature compression ratio as low as 1.81%, and a moderate curing time, which ensures both clinical operation time and can shorten the curing time to a certain extent. The biosafety of the material meets the standards.
[0064] Comparing the transparent silicone rubber material obtained in Comparative Example 1 with that obtained in Example 1, it can be seen that although the transparent silicone rubber material obtained in Comparative Example 1 has a light transmittance of 89.72%, its curing time is as long as 12 minutes, which indicates that it is prone to sticky residue when applied clinically. Comparing the transparent silicone rubber material obtained in Comparative Example 2 with that obtained in Example 1, the elastic modulus of the transparent silicone rubber material obtained in Comparative Example 2 is only 1.07 MPa, which is much smaller than the 1.32 MPa shown in Example 1. Comparing the transparent silicone rubber materials obtained in Comparative Examples 3 and 4 with those obtained in Example 1, the light transmittance of the transparent silicone rubber materials obtained in Comparative Examples 3 and 4 is 80.54% and 82.77%, respectively, indicating that the transparent silicone rubber materials obtained in Comparative Examples 3 and 4 cannot meet the requirements for high transparency. Comparing the transparent silicone rubber material obtained in Comparative Example 5 with that obtained in Example 1, it can be seen that the curing time of the transparent silicone rubber material obtained in Comparative Example 5 is only 3 minutes, which will result in curing during the operation, i.e., it cannot be applied clinically.
[0065] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A transparent silicone rubber material for dental impressions, characterized in that, The transparent silicone rubber material is composed of a base material and a catalyst, and the mass ratio of the base material to the catalyst is 7~8:
1. The substrate material comprises the following components in parts by weight: 100 parts vinyl-terminated polydimethylsiloxane, 8-12 parts benzyl silicone oil, 4-6 parts nano silica, 3-5 parts methyltriethoxysilane and 3-5 parts polyether-modified polysiloxane. The catalyst comprises the following components in parts by weight: 10-15 parts of hydrogen-containing silicone oil, 0.2-0.4 parts of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 0.05-0.1 parts of 1-ethynyl-1-cyclohexanol, and 0.5-1 parts of cerium oxide.
2. The transparent silicone rubber material for dental impressions according to claim 1, characterized in that, The viscosity of the vinyl-terminated polydimethylsiloxane is 18000~22000 mPa·s, and the particle size of the nano-silica is 10~15 nm.
3. The transparent silicone rubber material for dental impressions according to claim 1, characterized in that, The cerium oxide has a particle size of 20~50 nm.
4. A method for preparing a transparent silicone rubber material for dental impressions according to any one of claims 1 to 3, characterized in that, Includes the following steps: 1) A base material is obtained by mixing vinyl-terminated polydimethylsiloxane, benzyl silicone oil, nano silica, methyltriethoxysilane and polyether-modified polysiloxane; 2) A catalyst was obtained by mixing hydrogen-containing silicone oil, platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane, 1-ethynyl-1-cyclohexanol and cerium oxide; 3) The substrate material is mixed with the catalyst to obtain a transparent silicone rubber material.
5. The method for preparing a transparent silicone rubber material for dental impressions according to claim 4, characterized in that, In step 1), the mixing is carried out under a protective atmosphere, which is nitrogen.
6. The method for preparing a transparent silicone rubber material for dental impressions according to claim 5, characterized in that, In step 1), the mixing speed is 800~2500 rpm, the mixing temperature is 20~30℃, and the mixing time is 45~60 min.
7. The method for preparing a transparent silicone rubber material for dental impressions according to claim 6, characterized in that, In step 2), the mixing is ultrasonic mixing, the ultrasonic mixing frequency is 35~40kHz, and the ultrasonic mixing time is 13~18min.
8. The method for preparing a transparent silicone rubber material for dental impressions according to claim 7, characterized in that, In step 2), ultrasonic mixing is performed under light-protected conditions.
9. A method for preparing a transparent silicone rubber material for dental impressions according to claim 4, characterized in that, In step 3), the mixing time is 15~25s and the mixing temperature is 20~30℃.
10. The application of the transparent silicone rubber material for dental impressions as described in any one of claims 1 to 3 in dental impressions.