每年喷漆旺季，做汽车漆和木器漆的厂就要开始头疼一件事：CAB树脂一加进去，流平、干燥、光泽全跟着变。
加少了，漆膜流不平、橘纹一堆；加多了，干得快却脆、光泽发乌。配方师守着调漆缸调半天，就为找那个"刚刚好"的量。
更让人头疼的是，CAB正牌一吨价不低，换批次又得重调配方。小厂图便宜上副牌，结果丁酰基含量不对，一批漆喷出去光泽差一个度，整车返工。
说白了，CAB不是普通成膜树脂，是汽车面漆里那个"四两拨千斤"的助剂角色。这篇把CAB副牌的账算清楚。
CAB是给漆面"提气"的那个角色
CAB学名醋酸丁酸纤维素，是纤维素酯化时把一部分羟基换成丁酸酯基的产物。
跟CA比，它的丁酰基含量高，带来的好处是：溶剂里溶解性更好、跟涂料体系相容性更宽、漆膜柔韧、干燥快、光泽高、耐候好。所以汽车原厂漆、修补漆、木器漆、油墨里，CAB是常用的"流平兼增韧"助剂。
它不是主料，是改性助剂——加量不大，但缺了它漆面就少那股"精气神"。
全球格局。按产能和市场份额口径，国外前三家：
第一梯队是美国伊士曼（Eastman），CAB领域全球份额约四成五到五成，田纳西州Kingsport基地年产能约4万到6万吨，CAB-381系列是涂料行业的标杆牌号，长期主导高端汽车漆供应。
第二梯队是比利时索尔维（Solvay），年产能约2万吨，在欧洲涂料市场根基深。
第三梯队是日本大赛璐（Daicel），年产能约0.6万吨，走高纯特种路线。
全球CAB总产能也就8万多吨，这三家把高端盘子攥得很紧。
副牌不是次品，是丁酰基化验单上飘了一格
那CAB副牌怎么来的？
定义照旧：同一厂家同一牌号，出厂检验个别指标没完全踩线，合格的贴正牌，没完全达标的就是副牌。原厂原生粒子，不是再造粒。
四大来源：开停车头尾料、牌号切换过渡料、工艺波动致丁酰基含量或粘度小幅超标的批次、副线尾料。
| 类型 | 来源 | 品质 | 典型用途 |
|---|
| 正牌 | 原厂达标批次 | 全指标达标、批次稳 | 汽车原厂漆、高端修补漆 |
| 副牌 | 原厂未达标批次 | 个别指标小幅偏离，基材与正牌一致 | 木器漆、一般工业漆、油墨 |
| 回料/水口料 | 加工边角料再造粒 | 已受过一次热历史 | 低要求涂料 |
| 再生料 | 废旧塑料回收造粒 | 性能波动大 | 低端填充 |
CAB的关键指标是丁酰基含量和粘度。副牌往往就差在这两项——丁酰基差一两个百分点，或粘度跨半个等级。
伊士曼CAB-381，汽车漆圈的"标准答案"
先说伊士曼。这家在CAB领域几乎是代名词。
CAB-381系列是涂料行业用得最多的牌号，丁酰基含量、粘度分级细，配方师闭着眼都能调。它的优势是批次极稳，同一牌号跨一年的货，溶解速率和粘度几乎不飘。
它的副牌长什么样？多数是丁酰基含量差1个百分点左右、或者粘度落半级的料。分子骨架没换，溶解后清漆的成膜性跟正牌基本一致，但做汽车原厂漆这种要求批次纹丝不动的活儿就剔出来了。
用在哪？木器漆、一般工业漆、纸张清漆、油墨连接料。这些场合对丁酰基的容忍度宽一点，副牌顶得住。
索尔维，欧洲漆市里的老资格
再说比利时索尔维。这家在欧洲涂料圈是老牌玩家。
它的CAB产品配套欧洲汽车和木器漆体系，特点是跟醇酸、丙烯酸体系相容性好。它的副牌多为粘度波动的批次，或者配套特定客户规格时的过渡料。
用在哪？欧洲体系的木器漆、工业漆、罐头内壁涂料。碰到索尔维副牌，要注意它的溶剂体系偏欧洲配方，跟国产丙烯酸搭配时先小试相容性，别一上来就往大缸里倒。
还有个细节得提一嘴：CAB牌号看丁酰基和粘度两个维度，数字越小粘度越低、干燥越快。CAB-381那类是涂料主流，粘度高一点的适合厚涂，低一点的适合快干薄涂。副牌换牌号时，先确认是同一粘度级，别拿低粘度副牌顶高粘度正牌，漆膜一薄就露馅。
大赛璐，高纯特种那一档
第三家是日本大赛璐。它的CAB产能不大，走高纯特种路线。
高纯级CAB在高端油墨、特殊涂料里用得多，对灰分和残留控制极严。它的副牌，常见是灰分或粘度贴线的批次。
用在哪？一般工业漆、普通油墨。大赛璐副牌流通量小，但碰到高纯线下来的料，性价比不错。
同牌号CAB副牌丁酰基偏差常在±1个百分点内
CAB副牌怎么挑？几个硬指标。
第一，卡死丁酰基含量。CAB副牌最常翻车的就是丁酰基飘——差1个百分点，漆膜柔韧度和干燥速度都变，配方得重调。进厂先测丁酰基和粘度，这两项对上了再谈价格。
第二，对用途。汽车原厂漆、高要求修补漆上正牌；木器漆、一般工业漆、普通油墨，副牌够用。别拿副牌怼主机厂认证件。
第三，先做相容性小试。CAB跟树脂、溶剂的相容很挑，副牌换批次后先溶一杯看透明度，不浑浊、不析出再放大。
兰州有家做汽车修补漆的客户，之前图便宜上了批CAB副牌，丁酰基偏低，结果喷出来的清漆光泽比标准低一个多度，一批返修件整车返工。后来换成伊士曼CAB-381同牌号副牌，丁酰基和粘度每批对标，光泽波动从1.2个度压到0.2个度以内。
科隆仓库现货｜CAB破损
主推品牌：美国伊士曼Eastman、比利时索尔维Solvay、日本大赛璐Daicel。
主要牌号：CAB-381系列、索尔维CAB、大赛璐高纯CAB。
包装规格：大包装、小包装都有，小包装试机打样，大包装、吨包料量产摊薄。
仓库现货：CAB副牌仓库现货通常在5000吨左右，常年备货不断档。
其中小包副牌备货800-1000吨、箱装副牌备货300-500吨、大包料/吨包料备货3500-3900吨，按订单配比灵活出。
供应保障：先测后签，指标对上再放货。
六句口诀，CAB副牌调漆不翻车
汽车原厂漆、主机厂认证件——正牌，别省；
木器漆、一般工业漆——副牌可用，先测丁酰基；
欧洲树脂体系——认准索尔维路线；
高纯油墨、特殊涂料——看大赛璐；
换批次先溶一杯看相容性；
别拿副牌怼光泽度认证件。
CAB这助剂，量不大但管事。选对副牌，一桶漆的成本能压一截；选错了丁酰基，一整车返工的钱够买好几吨正牌。
Every year during the peak paint season, factories producing automotive and wood paints start to face a headache: once CAB resin is added, the smoothing, drying, and gloss all change accordingly.
If you add too little, the paint film won't even flow and there will be many orange marks; If you add too much, the paint dries quickly but becomes brittle and the gloss turns black. The formulator waits for a long time adjusting the paint mixing tank, just to find the "just right" amount.
What's even more troublesome is that the price per ton of genuine CAB is high, and changing batches means the formula must be readjusted. Small factories try to get a cheap secondary brand, but the butyl content is wrong, so the gloss is one degree lower in a batch and the whole vehicle needs to be reworked.
To put it simply, CAB is not an ordinary film-forming resin; it plays the role of a "small amount of effort" additive in automotive topcoats. This article clarifies the accounts of CAB's secondary brands.
CAB is the one that "energizes" the paint surface
CAB Scientific name is cellulose acetate butyrate, a product of replacing some hydroxyl groups with butyrate groups during cellulose esterification. Compared to CA,
has a higher butyl content and benefits: better solvent solubility, wider compatibility with coating systems, flexible paint film, fast drying, high gloss, and good weather resistance. Therefore, CAB is a commonly used "leveling and toughening" additive in automotive original paints, repair paints, wood paints, and inks.
It's not the main ingredient, but a modifying additive—not a big addition, but without it, the paint lacks that 'spirit'.
Global Landscape. By capacity and market share, the top three foreign companies are:
The first tier is Eastman from the US, with a global CAB market share of about 45–50%. The Kingsport base in Tennessee has an annual capacity of about 40,000 to 60,000 tons, and the CAB-381 series is a benchmark brand in the coatings industry, long dominating the supply of high-end automotive paints.
The second tier is Belgium's Solvay, with an annual capacity of about 20,000 tons and a deep foundation in the European coatings market.
The third tier is Japan's Daicel, with an annual capacity of about 6,000 tons, following a high-purity specialty route.
Global CAB production capacity is just over 80,000 tons, and these three firmly hold onto the high-end market.
The sub-brand isn't defective; it's a column floating on the butyryl test report .
So how did the CAB sub-brand come about?
Definition as usual: Same manufacturer, same grade. If some indicators aren't fully met during factory inspection, the qualified ones are labeled as legitimate, and those that don't meet the standard are sub-brands. Original factory virgin particles, not re-pellets.
Four main sources: start-stop and tail materials, grade switching transition materials, batches with butyryl content or viscosity slightly exceeding standards due to process fluctuations, and auxiliary tailings.
| Type | Source | Quality | Typical Use |
|---|
| Genuine Brand | Original Factory Standard Batch | Full Indicator Compliant, Batch Stable | Original Automotive Paint, High-End Repair Paint |
| Subbrand | Original factory substandard batch | Slight deviations in some indicators, base material consistent with genuine brand | Wood paint, general industrial paint, ink |
| Reused/sprue material | Processed scraps repelled | Already undergone one heat history | Low Requirement Coating |
| Reclaimed material | Recycled plastic pelletizing | Large performance fluctuations | Low-end filling |
CAB The key indicators are butyryl content and viscosity. The secondary brands often differ by just these two points—the butyl group difference is one or two percentage points, or the viscosity is half a grade higher.
Eastman CAB-381, the "standard answer" in the automotive paint circle
Eastman First. This brand is almost synonymous with the CAB field. The
CAB-381 series is the most widely used grade in the coatings industry, with finely graded butyl content and viscosity, allowing formulators to adjust it with their eyes closed. Its advantage is extremely stable batch size; for products of the same grade spanning a year, the dissolution rate and viscosity are almost unchanged.
What does its secondary brand look like? Most are materials with butyl content differing by about 1 percentage point or viscosity half a grade lower. The molecular framework hasn't been replaced, and after dissolution, the film-forming properties of clear varnish are basically the same as genuine brands, but for OEM automotive paints, which require batch immovability, it still gets removed.
Where is it used? Wood paint, general industrial paint, paper varnish, ink binder. In these cases, the tolerance for butyl groups is a bit more lenient, so the secondary brand can handle it.
Solvay, a veteran in the European paint market
Let's talk about Belgium's Solvay. This company is a long-established player in the European paint scene.
Its CAB products are compatible with European automotive and wood paint systems, characterized by good compatibility with alkyd and acrylic systems. Its secondary brands are mostly batches with varying viscosity or transition materials for specific customer specifications.
Where is it used? European system wood paints, industrial paints, and canning interior wall coatings. When dealing with Solvay secondary brands, note that their solvent system leans toward European formulas. When paired with domestic acrylic, first test compatibility and don't pour it straight into the big tank.
One more detail to mention: CAB grades are based on butyryl and viscosity dimensions. The smaller the number, the lower the viscosity and the faster it dries. CAB-381 is the mainstream coating; higher viscosity is suitable for thick applications, lower ones for quick-drying thin coats. When changing secondary brands, first confirm they are the same viscosity grade. Don't use low-viscosity secondary cards against high-viscosity genuine brands, as the paint film will be exposed as soon as the film thins.
Da Cellu, the high-purity specialty grade
The third company is Japan's Da Salu. Its CAB production capacity is not large, so it follows the high-purity specialty route.
High-purity CAB is widely used in high-end inks and special coatings, with very strict control over ash content and residue. Its secondary brands are commonly used for batches with ash content or viscosity and line coatings.
Where is it used? General industrial paints and ordinary inks. Large Cellu's secondary brand has a small circulation volume, but when it comes to materials from the high-purity line, it offers good cost performance.
For the same grade CAB secondary brand, the butyl group deviation is often within ±1 percentage point
CAB How to choose a secondary brand? A few hard indicators.
First, the butyl content is completely trapped. The most common mishap with CAB secondary brands is butyryl group drift—a 1 percentage point difference changes the film's flexibility and drying speed, so the formula needs to be readjusted. Before entering the factory, test the butyl group and viscosity; once these two match, negotiate the price.
Second, consider the intended use. Genuine automotive paint and high-demand repair paints should be genuine brands; Wood paints, general industrial paints, and ordinary inks—secondary brands are sufficient. Don't use secondary brands to challenge OEM certified parts.
Third, do a compatibility test first. CAB is very selective about compatibility with resins and solvents. After changing batches, first dissolve a cup to check transparency—if it's not cloudy or precipitated, then zoom in.
A customer in Lanzhou who does automotive repair paint previously ordered a batch of CAB secondary brands cheaply, with low butyryl levels, resulting in a clear paint gloss more than a degree lower than the standard. A batch of reworked parts required full vehicle rework. Later switched to Eastman CAB-381 sub-brand, matching butylic and viscosity per batch, reducing gloss fluctuation from 1.2 degrees to within 0.2 degrees.
Cologne warehouse in stock | CAB damage
Main brands: Eastman (USA), Solvay (Belgium), Daicel (Japan).
Main grades: CAB-381 series, Solvay CAB, high-purity CAB (Grand Cellulum).
Packaging Specifications: Both large and small packages are available. Small packages are tested for testing and sampling; large packages and ton-sized packaging are mass-produced and thinned.
Warehouse Stock: CAB sub-brand warehouses usually have stock around 5,000 tons, with continuous stock year-round
Among them, small-package secondary brand stock is 800-1000 tons, boxed secondary brand stock is 300-500 tons, large-bag/ton-bag stock is 3500-3900 tons, flexibly allocated according to order proportions.
Supply guarantee: test first, sign later; release materials only after indicators match.
Six-line mnemonic: CAB secondary brand paint mixing without mishaps
Automotive OEM paint, main engine factory certified parts—use the primary brand, don’t skimp;
Wood coatings, general industrial coatings—secondary brand can be used, test phthalic anhydride first;
European resin systems—follow the Solvay route;
High-purity inks, special coatings—refer to Daserlu;
When changing batches, dissolve a cup first to check compatibility;
Don’t use secondary brand on gloss-certified parts.
This CAB additive has a small quantity but is effective. Choosing the right secondary brand can reduce the cost of a barrel of paint; choosing the wrong phthalic anhydride can cost enough to rework an entire vehicle, which could buy several tons of the primary brand.
