衬套贴残肢，太硬磨皮太松晃。假肢衬套硬度表硬凑，换体系才是治本。
结论先摆：假肢衬套，贴肤缓冲绑一起
假肢衬套是“贴残肢的件”：贴肤、缓冲、支撑。材料要贴肤好、缓冲好、支撑稳——结论先给：假肢衬套用凝胶 TPE 是主流；致敏要求高，医用硅胶留。
假肢衬套最大的坑：硬度上不去，换体系才治本。硬度表上硬凑，不如换体系——体系，是硬度的天花板。
假肢衬套是体验件：压疮、磨破都是问题。材料选对，佩戴才安心——体验件，别省料钱。
TPE凭啥护残肢：贴肤可做，缓冲可加
假肢衬套用 TPE 的理由：贴肤可做、缓冲可做、硬度可调、效率高——四条合起来，适合衬套。
贴肤是核心：贴残肢一整天。致敏测试写进验收——过敏，就是问题。
缓冲不能省：减震缓冲。缓冲数据写进验收——压疮，就是问题。
戴一天走它：皮肤、承重、支撑
贴肤工况：贴一整天。致敏数据要验——过敏，就是问题。
缓冲工况：行走缓冲。缓冲数据要验——压疮，就是问题。
支撑工况：承重支撑。压缩数据要验——塌陷，就是问题。
凝胶TPE还是硅胶：衬套上看磨不磨皮
| 维度 | 凝胶 TPE | 硅胶 |
|---|
| 贴肤 | 可做 | 好 |
| 缓冲 | 好 | 好 |
| 硬度 | 可调 | 偏软 |
| 成本 | 中 | 中高 |
| 效率 | 注塑 | 硫化 |
| 批次 | 稳 | 稳 |
表格读法：硅胶贴肤好但贵、硫化慢；凝胶 TPE 性价比高——常规衬套凝胶 TPE，高致敏硅胶。
按致敏要求选：高致敏硅胶，常规凝胶 TPE。
体系匹配表：别在硬度表硬凑
| 硬度需求 | 推荐体系 | 理由 |
|---|
| 很软 | 凝胶 TPE | 缓冲 |
| 偏软 | SEBS 基 | 平衡 |
| 中软 | TPU 复合 | 支撑 |
| 硬 | 不用 TPE | 换材料 |
表格读法：同一 Shore 值下 SEBS、TPU、TPV 手感天差地别，换体系比硬凑硬度表管用。
体系，是硬度的天花板。
两个坑：硬度表硬凑、贴肤造假
坑一：硬度表硬凑。在现体系里加填料提硬度，衬套又硬又闷——先选体系。
坑二：贴肤虚标。报告写贴肤，实际过敏——致敏测试，必测。
坑三：缓冲漏测。压疮——缓冲测试，必测。
验收三问：贴肤、透气、批次
三问：贴肤测试有没有、缓冲按什么标准、体系推荐是什么。一验：实际佩戴实测——三问一验，供应商底细清楚。
体系验证要先行：先定贴肤要 SEBS 还是要 TPU，再谈价格——体系，是硬度的天花板。
留样要成习惯：每批留样，贴肤缓冲按批次复测。批次换料先对比再放量——批次稳，客诉少。
假肢衬套 Shore 00 30-50 凝胶感——软而有支撑，分散残肢压力。缓冲性能和压力分散数据要验，老化后缓冲剩多少也要测。衬套选型，缓冲和透气一起看。
衬套用几个月变硬不缓冲——汗液、紫外线、反复清洗加速老化。老化后缓冲性能衰减，残肢局部受压。变硬不是旧了，是老化把缓冲吃掉了。
硬度上不去换体系才治本——SEBS 基、TPV、凝胶 TPE 各有硬度下限。硬度需求超出体系能力，硬凑就是性能换不来舒适。硬度不够，换体系比调配方管用。
按目标更换周期推荐材料——更换周期长材料要求高，更换频繁成本高。把残肢承重分布和透气要求给供应商。
更换周期定了，材料档位才定。
衬套是“残肢和假肢之间的软垫”——要软、要透气、要分散压力。太致密闷热，太疏松支撑不足，平衡点靠材料和结构配合。
软垫的账，按承重和透气算。
假肢接受腔衬套常见问题与对策表
| 现象 | 原因 | 对策 |
|---|
| 压疮 | 缓冲不足 | 换凝胶料 |
| 过敏 | 致敏物质 | 换低敏料 |
| 塌陷 | 压缩变形大 | 换耐压料 |
| 磨破 | 表面摩擦 | 加处理 |
| 硬度凑不上 | 体系不对 | 换体系 |
假肢衬套 TPE 邵氏硬度按 Shore A 20-30 选，残端贴合不磨破。 衬套内壁要绒感防滑，外壁要透气排汗——双层共挤结构，内层软外层韧。
假肢衬套透气按水蒸气透过量 >500 g/m²·24h 验收。 残端皮肤出汗闷久了溃烂，透气量比手感更影响佩戴体验——透气孔设计和材料透气率一起考虑。
科隆客户案例：硬度批次漂移手感忽软忽硬，换体系过弯折
合肥一家医疗器械厂，假肢衬套硬度批次漂移，手感忽软忽硬。科隆配合换体系换牌号（SEBS 基换 TPV 基），-40℃ 低温弯折一次通过。体系换了，批次问题从源头断——批次漂移，先看体系稳定性。
小结
假肢衬套的选型，体系先定，贴肤再测，硬度上不去换体系才治本，别硬凑。
A liner that sticks to residual limbs is too hard, causing skin abrasion, or too loose, causing wobbling. The hardness chart for prosthetic liners is just an approximation; changing the system is the fundamental solution.
Conclusion first: prosthetic liner, skin-contact cushioning tied together
Prosthetic liners are the 'pieces that attach to the residual limb': they adhere to the skin, provide cushioning, and offer support. The material should adhere well to the skin, cushion well, and support steadily — conclusion first: using gel TPE for prosthetic liners is mainstream; for high sensitivity requirements, medical-grade silicone is retained.
The biggest pitfall of prosthetic liners: they can't get hard enough; changing the system is the fundamental solution. Relying on the hardness chart to force it is not as good as changing the system—the system is the ceiling of hardness.
Prosthetic liners are trial pieces: pressure sores and abrasions are issues. Choosing the right material ensures comfort while wearing them—since they are trial pieces, don’t skimp on the material.
Why TPE Protects Disabled Limbs: Can Be Skin-Applied, Cushioning Can Be Added
Reasons for using TPE for prosthetic liners: can be skin-friendly, can provide cushioning, hardness can be adjusted, high efficiency — together, these four points make it suitable for liners.
Skin contact is key: keep the residual limb attached all day. Write the sensitization test into the acceptance — if allergic, it’s a problem.
Cushioning cannot be skipped: shock absorption cushioning. If cushioning data is written into acceptance—bedsores, then it’s a problem.
Wear it all day: Skin, weight-bearing, support
Skin contact condition: Wear it all day. Sensitization data must be tested—if it causes an allergy, that's a problem.
Buffer condition: walking buffer. Buffer data needs to be checked—bedsores, that's the problem.
Support working condition: load-bearing support. Compressed data must be checked—collapse, that's the problem.
Gel TPE or silicone: check if the bushing rubs the skin
| Dimension | Gel TPE | Silicone |
|---|
| close-fitting | Can be done | Good |
| Buffer | Good | Good |
| Hardness | Adjustable | Somewhat soft |
| Cost | middle | Medium-high |
| Efficiency | Injection molding | Vulcanization |
| Batch | Stable | Stable |
Table reading: Silicone is skin-friendly but expensive and slow to vulcanize; gel TPE is cost-effective — conventional bushing gel TPE, highly sensitizing silicone.
Select according to sensitization requirements: high-sensitization silicone, conventional gel TPE.
System Matching Table: Don't force it on the hardness table
| Hardness requirements | Recommendation system | Reason |
|---|
| Very soft | Gel TPE | Buffer |
| Somewhat soft | SEBS base | Balance |
| ChinaSoft | TPU composite | Support |
| hard | No need for TPE | Change materials |
Table reading: With the same Shore value, the feel of SEBS, TPU, and TPV is vastly different; switching systems is more effective than forcibly adjusting the hardness scale.
System is the ceiling of hardness.
Two pitfalls: stiffness chart fudging, fake skin attachment
Pitfall 1: Forcing hardness with the hardness scale. Increasing hardness by adding fillers in the current system makes the lining both hard and stifling—choose the system first.
Pitfall #2: Mislabeling as skin-friendly. The report claims it is skin-friendly, but in reality, an allergy test—sensitization test—is necessary.
Pitfall 3: Missed cushioning test. Pressure ulcers — cushioning test is a must.
Three acceptance questions: skin adhesion, breathability, batch
Three questions: Is there a skin patch test, what are the standards for cushioning, and what does the system recommend. One test: actual wearing test—three questions and one test, the supplier's details are clear.
System verification must come first: first determine whether the skin-contact material should be SEBS or TPU, then discuss the price — the system sets the ceiling for hardness.
Making sample retention a habit: retain samples from each batch, and re-test the skin buffer by batch. When changing materials for a batch, compare first before scaling up — stable batches lead to fewer customer complaints.
Prosthetic liner Shore 00 30-50 gel feel — soft yet supportive, disperses residual limb pressure. Cushioning performance and pressure distribution data need to be tested, and how much cushioning remains after aging should also be measured. When selecting a liner, consider cushioning and breathability together.
The bushing becomes hard and loses cushioning after a few months—sweat, UV rays, and repeated cleaning accelerate aging. After aging, cushioning performance deteriorates, causing local pressure on residual limbs. Hardening is not due to wear; aging has consumed the cushioning.
If the hardness can't be increased, changing the system is the fundamental solution—SEBS-based, TPV, and gel TPE each have lower limits for hardness. When the hardness requirement exceeds the system's capability, forcing it results in performance without bringing comfort. If the hardness is insufficient, changing the system is more effective than adjusting the formulation.
Recommend materials according to the target replacement cycle — materials with a long replacement cycle have high demands, frequent replacements are costly. Provide the supplier with the residual limb's load distribution and breathability requirements.
The replacement cycle is determined, only then is the material grade determined.
A liner is the 'cushion between a residual limb and a prosthesis'—it needs to be soft, breathable, and able to distribute pressure. If it's too dense it gets hot, if it's too loose it doesn't provide enough support; the balance depends on the combination of material and structure.
The account for cushions is calculated based on load-bearing and breathability.
Table of Common Problems and Countermeasures for Prosthesis Socket Liners
| Phenomenon | Reason | Countermeasure |
|---|
| Pressure ulcer | Insufficient buffer | Change the gel material |
| Allergy | Allergen | Switch to hypoallergenic material |
| collapse | Large compression deformation | Change to high-voltage resistant material |
| worn out | Surface friction | Add processing |
| The hardness doesn't add up | The system is wrong | Change system |
Prosthetic liner: TPE with Shore A hardness of 20-30 is selected, fitting the residual limb without causing abrasions. The inner wall of the liner should have a velvety, non-slip texture, and the outer wall should be breathable and sweat-wicking—a double-layer co-extrusion structure with a soft inner layer and a tough outer layer.
Prosthetic liners are considered acceptable if breathability allows water vapor transmission >500 g/m²·24h. If the residual limb skin sweats and stays damp for a long time, it can ulcerate; breathability affects the wearing experience more than the feel—both the design of ventilation holes and the material's breathability should be considered together.
Cologne Customer Case: Hardness batch drift causes the feel to be sometimes soft and sometimes hard, switching systems for bending
A medical device factory in Hefei experienced batch drift in the hardness of prosthetic liners, with the touch feeling sometimes soft and sometimes hard. Cologne coordinated a system change and switched grades (from SEBS-based to TPV-based), passing the -40°C low-temperature bend test in one go. With the system changed, batch problems are cut off from the source—when there is batch drift, first look at system stability.
Summary
When selecting a prosthetic liner, first determine the system, then measure it against the skin. If the hardness is insufficient, changing the system is the fundamental solution; don’t force it.
