Waterborne Epoxy Insulating Varnish vs. Solvent-Based: A Deep Dive into VOCs, Costs, and Compliance

On 2026/6/1, GB 30981.2-2025 "Limit of Harmful Substances in Coatings – Part 2: Industrial Coatings" officially became mandatory. Traditional solvent-based epoxy insulating varnishes typically contain 500–650 g/L VOCs, whereas water-based epoxy insulating varnishes can achieve <50 g/L—a gap exceeding 10-fold. For motor manufacturers in Guangzhou and the Pearl River Delta, tightening regulations across three fronts—emission limits for organized sources (20 mg/m³), hazardous chemical storage requirements, and export customer RoHS/REACH compliance audits—mean that transitioning from oil-based to water-based is no longer a cost issue but a matter of regulatory compliance.

本文以广州飞思FS7100系列水性环氧绝缘漆实测数据为基准，从核心参数、优缺点、综合成本、环保合规四个维度，对水性环氧绝缘漆与溶剂型绝缘漆进行深度对比，帮助电机厂做出清晰的换漆决策。

一、为什么现在必须重提水性绝缘漆vs溶剂型绝缘漆

GB 30981.2-2025于2025年5月30日发布，2026年6月1日强制实施。该标准把工业涂料按水性（W）、溶剂型（S）、无溶剂（F）、辐射固化（R）分型管控，VOC限值分品类加严，并新增SVOC、辅材（稀释剂/固化剂）全覆盖监管。

Traditional solvent-based epoxy insulating varnishes typically have VOC levels of 500-650 g/L, while waterborne epoxy insulating varnishes can achieve <50 g/L—a gap exceeding 10-fold. For motor manufacturers, this means three production lines tightening simultaneously:

1. 环保排放限值：珠三角有组织排放限值20 mg/m³，溶剂型漆末端治理极易波动超标

2. 危化品仓储：溶剂型漆属低闪点危化品，需防爆仓+资质车间

3. Export Supply Chain Audit: Wind power, new energy drive motors, and export appliance clients have set insulation paint VOC ≤ 100 g/L as a supplier entry requirement.

Conclusion: The shift to oil-free is no longer a cost issue, but a compliance one.

II. Core Parameter Comparison (Same-Level Epoxy Systems)

以下为飞思FS7100系列水性环氧绝缘漆与传统溶剂型环氧绝缘漆的关键参数对比：

三、优缺点深度拆解

1. Water-based Epoxy Insulating Varnish

Advantages:

• 源头VOC趋零，轻松过环评、绿色工厂、出口供应链审核

• Non-combustible and non-explosive; eliminates the need for explosion-proof retrofitting in the impregnation workshop, reducing fire inspection pressure.

• 单组份开桶即用（飞思FS7100系列），浸漆槽10天不施工不凝胶

• 漆膜无溶剂针孔，高湿/变频电机绝缘电阻衰减慢

• 飞思实测：FS7100粘结强度120 N，FS7230防闪锈耐水洗，适配家电/工业电机

Cons:

• Drying temperature should be slightly higher than for oil-based products, at 5-10°C, or use the same temperature for an additional 20-30 minutes.

• 储漆罐必须用不锈钢，普通碳钢生锈会破乳

• Early low-cost waterborne paints fail salt spray and damp-heat tests; selecting the right modified epoxy system is key.

1. Solvent-based insulation varnish

Advantages:

• Fast penetration, quick surface drying, minimal modification to existing production lines.

• 对极个别H级以上高温工况历史验证数据多

• 单价采购成本低

Cons:

• High VOC: Most legacy formulas do not comply with GB 30981.2-2025.

• 苯系溶剂致职业危害，车间需防毒防爆

• 稀释剂易挥发，单班耗漆量大

• 危废漆渣+末端RTO天然气能耗，隐性年成本数十万起

• New energy/wind power/export clients have set VOC ≤ 100 g/L for insulation varnish as an entry requirement.

4. Cost Breakdown: Don't Just Look at Price Per Kilogram

以一条中型电机定子连续沉浸线为例（年处理约50万件）：

1. 溶剂型综合成本

• 漆单价低，但加上预热电耗+稀释剂损耗+RTO运维+危废处置（千元/吨级）+防爆电工证/体检

• 综合单件成本反而上浮10-25%

1. Water-based Epoxy Total Cost (Freesia FS7100)

• 漆单价高5-15%，但免预热、免稀释剂、免大面积RTO改造、漆渣少、工效高

• Break-even on price difference within 3-6 months of mass production

1. Feishu Customer Measurement Standards

• 家电定子单件绝缘处理物料+能耗，水性比油性低约0.1-0.15元/件

• The larger the scale, the greater the savings.

5. Environmental Compliance: Only Two Paths After 2026 Years

1. Source Substitution (Recommended)

• Water-based (VOC < 50 g/L) or solvent-free (near-zero)

• 新建/改扩建线低VOC替代率地方要求≥80%

1. Force the last mile (not recommended)

• 保留溶剂漆+RTO+在线监测

• 投资大，且珠三角20 mg/m³有组织限值下极易波动超标

1. Supply chain-driven pressure

• Wind power, new energy drive motors, and export home appliance customers have already included "insulating paint VOC ≤ 100 g/L" in supplier qualification criteria.

• 溶剂型漆在增量市场中逐步丧失投标资格

六、广州飞思水性环氧绝缘漆选型速查

1. FS7100绝缘漆系列（通用主力款）

• Application: General motors, small and medium-sized motors, transformers

• 电气强度：100 MV/m

• Bond Strength: 120 N

• Cure: 120-130°C × 2-3h

• Features: Single-component waterborne epoxy; immersion tank remains non-gelled for 10 days.

1. FS7230绝缘漆系列（低温快干款）

• Compatible with: Fan, Washing Machine, and Air Conditioner Motors

• Cure: 80-120°C × 80-120 min

• Features: Anti-flash rust, resistivity ≥ 10¹⁴ Ω·m after 24h immersion

• 适配：对烘箱温度敏感或节能产线

1. FS7236绝缘漆系列（耐振款）

• Compatible with: Compressors / Industrial Motors

• 特点：强化韧性耐振动

1. FS7231 Insulating Varnish Series (Precision Edition)

• 适用：高频变压器/精密线圈

• Features: No lacquer buildup, no clogged holes

All products in this series are single-component waterborne epoxies, non-hazardous, with VOC < 50 g/L, and support dip or vacuum impregnation.

七、施工关键：双温红线

Freescale Technical Tip: Strictly maintain two temperature limits; breaching either causes emulsion failure.

1. Workpiece temperature threshold

• 浸漆前工件必须冷却至室温

• Do not place hot workpieces (e.g., immediately after preheating) directly into the tank.

1. 漆液温度红线

• During construction, control the paint temperature in the dip tank below 30-40°C (FS7230 requires stricter control: ≤30°C; general specification: ≤40°C).

• Emulsion skinning or breaking due to overheating; scrapped.

Add:

• 原漆储存：25℃以下阴凉处

• 兑水用去离子水/自来水，别混油性漆

• The paint reservoir must be made of 304/316 stainless steel to prevent emulsion breakdown caused by carbon steel rust.

8. Key Points for Retrofitting Legacy Production Lines

There are only three changes to the legacy production line:

1. Vats/Piping Replacement: 304/316 Stainless Steel (Prevents Emulsion Breakdown from Carbon Steel Rust)

2. Cancel preheating or retain but reduce frequency

3. Keep the oven exhaust vent clear for moisture removal.

No explosion-proof equipment required. As long as the old oven maintains a stable temperature of 130°C, replacement is generally unnecessary. For Feisi FS7100, we recommend curing at 120-130°C for 120-180 minutes. Alternatively, with accelerator FS710, cure at 0°C to reduce temperature to 110-120°C for 80-100 minutes. FS7230 can be cured at 80-120°C for 80-120 minutes. This process requires either 5-10°C higher than solvent-based systems at the same temperature, or an additional 20-30 minutes at the same temperature.

IX. FAQ: Common Selection Questions

Q1: Which is better, water-based epoxy insulation varnish or solvent-based insulation varnish?

没有绝对更好，只有更适配工况。若看环保合规、车间安全、出口供应链准入、长期综合成本：水性环氧绝缘漆优于溶剂型，尤其2026-06-01 GB 30981.2-2025强制实施后，溶剂型老配方多数VOC不达标。若看绝对采购单价、极老旧产线零改动：溶剂型仍有微小优势，但隐性成本（RTO气耗、危废、防爆运维）会抵消差价。飞思口径：新增产线/家电电机/新能源驱动/出口订单直接选水性；存量非标超高温特殊工况再做小批量验证。

Q2：GB 30981.2-2025对绝缘漆VOC限值是多少？何时强制实施？

Mandatory Implementation Date: 2026-6-1 (Published 2025-05-30, Current Mandatory National Standard). The standard categorizes industrial coatings into waterborne (W), solvent-based (S), solvent-free (F), and radiation-curing (R) types for control, including thinners and curing agents as auxiliary materials. Typical volatile organic compound (VOC) limits for waterborne epoxy insulating varnish are <50 g/L, significantly lower than the common 500-650 g/L range for solvent-based epoxy insulating varnish. Specific limit tiers follow the corresponding coating types in the standard's main text; however, the general trend is a much broader allowance for waterborne coatings and stricter restrictions for solvent-based ones.

Q3：水性绝缘漆真的比溶剂型贵吗？综合成本如何？

Higher unit purchase price (5–15%) results in a lower overall cost per piece. Water-based: eliminates preheating energy, requires no thinners, reduces or removes RTO end-of-pipe treatment, classifies hazardous waste as general solid waste, and improves efficiency. Solvent-based: cheaper paint, but incurs hidden costs from thinner loss (accounting for 15–20% of paint cost), preheating electricity, RTO natural gas consumption, HW06 hazardous waste disposal, and explosion-proof maintenance—raising the single-piece cost by approximately 0.1–0.15 yuan. Feisi customer data shows that mass production of medium-sized stators breaks even on the price difference within 3–6 months; the larger the scale, the greater the savings.

Q4: Does water-based paint require high curing temperatures? Can it be used directly on existing production lines?

飞思FS7100推荐120-130℃×120-180 min（可加促进剂FS7100C-2降至110-120℃×80-100 min）；FS7230可80-120℃×80-120 min固化。比溶剂型同温多5-10℃或同温多20-30 min，老烘箱只要能稳到130℃基本不用换。老产线改动点只有三个：浸漆槽/管路换304/316不锈钢（防碳钢锈破乳）；取消预热段或保留但降频；烘箱出风口保通畅排湿。无需上防爆。

Q5: What are the dual temperature thresholds for water-based paint application?

飞思技术Tips：严控两条温度红线，破一条就破乳。工件温度红线：浸漆前工件必须冷却至室温，严禁热工件（如刚脱预热炉）直接入槽；漆液温度红线：施工时浸漆槽漆温控制在30-40℃以下（FS7230要求更严≤30℃，通用口径≤40℃），超温乳液结皮/破乳报废。补充：原漆储存25℃以下阴凉处，兑水用去离子水/自来水，别混油性漆。

Q6：FS7100和FS7230系列怎么选？

FS7100系列：通用主力款，120-130℃×2-3h，电气强度70-100 MV/m（FS7100-130标称70，高阶批次可达100 MV/m），体积电阻1-10×10¹⁴ Ω·m常态，粘结80-120 N；中小型电机、电器线圈、工业定子沉浸首选。FS7230系列：低温快干款，80-120℃×80-120 min固化，防闪锈、浸水24h电阻率保持好；风扇电机、洗衣/空调电机、低频变压器、对烘箱温度敏感或节能产线选它。一句话：要耐温等级和通用性选FS7100；要低温快干、家电小电机/变压器选FS7230；压缩机耐振选FS7236，高频精密线圈选FS7231。

10. Summary

Water-based epoxy insulation varnish is not an environmental compromise—it's the default solution for motor insulation in the GB 30981.2-2025 era. Solvent-based products won't vanish overnight, but new production lines, export orders, and water-based adoption rates in Guangdong Pearl River Delta factories will continue rising to 80%+.

Guangzhou Feisi Synthetic Materials Co., Ltd. | Expert in Waterborne Epoxy Insulating Resins and Self-Adhesive Coating Solutions

如需FS7100系列TDS、VOC检测报告或试样，请联系：

• 电话：020-8251-3918

• Email: sales@gzfaith.com

• Website:www.gzfaith.com

• Address: Building G2, No. 31 Kefeng Road, Huangpu District, Guangzhou