同一款蓝色家电外壳，两批货放在一起对比，色差肉眼可见——一批偏蓝一批偏灰。组装线上混装后，客户巡检时直接发现，要求全部返工重新调色。调色师傅熬了两个通宵，查出来是色母粒用了干粉颜料直接混，分散不均，批次间色差ΔE超过3。
你手上那只手机壳的白，可能和你家乳胶漆来自同一类原料——只是绝大多数人从没问过。
本文由长期经营塑料原料及助剂的宁波市科隆新材料有限公司整理，牌号与批次信息以实际供货渠道为准。
着色剂速查总表：颜料、染料、色母粒三条路
着色剂不是一个东西，而是一整套调色工具箱：白色钛白粉、黑色炭黑打底，无机和有机颜料上彩色，工业化再打包成色母粒。下面这张表把主流品种一页列清。
| 体系 | 代表品种 | 关键参数 | 典型制品 | 添加比例 |
|---|
| 白色颜料 | 金红石型/锐钛型钛白粉 | R型耐候好、A型白度高 | 家电、日用品、板材 | 0.5%-3% |
| 黑色颜料 | 色素炭黑 | 着色兼抗紫外线 | 家电外壳、管材、汽车件 | 0.5%-2% |
| 无机彩色颜料 | 氧化铁、群青、铬系 | 耐温耐候、色偏沉稳 | 户外件、建材 | 0.5%-3% |
| 有机颜料 | 酞菁蓝、永固红、联苯胺黄 | 颜色鲜艳、耐温一般 | 日用品、包装 | 0.3%-1.5% |
| 色母粒 | 各品种浓缩母粒 | 分散好、易计量 | 工业化量产 | 2%-5% |
注：以上耐温耐候为常见参数，具体色差和迁移性以官方TDS和打板实测为准。先定颜色和耐候要求，再选颜料类型，最后决定走色粉还是色母粒。
图1 着色剂——钛白粉、炭黑与彩色颜料颗粒
着色剂是塑料的彩妆师，色母粒才是工业化答案
这位主角，是塑料的彩妆师。宁波市科隆新材料有限公司长期经营各类塑料助剂及改性原料，覆盖国内外多个品牌货源，在钛白粉、炭黑、色母粒等着色相关品类上有稳定供货渠道。着色剂这个品类，本质上就是塑料的“彩妆师”——灰白的树脂颗粒靠它才有了颜色，而工业化量产要的稳定和干净，靠的不是颜料干粉，是预先做好的色母粒。
着色这活儿和化妆一个理：底色调稳了，彩妆才不会一上来就翻船。
从机理讲，颜料靠散射和吸收光线显色。钛白粉折射率高，把光反复散射掉就显出白；炭黑几乎吸收所有光就显黑；有机颜料分子选择性吸收特定波长就显出彩色。颜料在树脂里必须分散成极细颗粒，一旦团聚，颜色就发花、表面出现色点。色母粒就是把高浓度颜料预先分散在载体树脂里做成颗粒，加料干净、分散均匀、计量方便，是规模化生产的标准答案。
把钛白粉微粒铺进透明树脂，光线撞上去被一遍遍弹开，白就这么浮了出来。
钛白粉还分金红石和锐钛两种晶型：金红石型折射率更高、耐候性好，户外件优先选它；锐钛型白度更柔和但耐候偏弱，适合室内。炭黑除了把东西染黑，还能吸收紫外线，户外黑件相当于免费送一层抗UV，一举两得。
金红石和锐钛不是同一种白——拿锐钛去做户外件，等于让娇小姐顶太阳，三个月就泛黄。
炭黑不只是黑，它还是免费的抗紫外线帮手，户外黑件一举两得。
逐品种速查：钛白粉打底，炭黑兼抗UV，色母粒管量产
品种看着多，抓住几类主力就能盖住八成调色需求。
无机颜料耐温耐候但颜色发闷，有机颜料鲜艳但耐温差一点，搭着用才鲜亮又耐用。
钛白粉（二氧化钛）：用量大的白色颜料。做家电外壳、板材、日用品白件，优先金红石型；做室内柔白或成本敏感，锐钛型也能用。注意：钛白粉量大了会影响冲击强度和表面光泽，要和填料一起平衡。
供货提示：钛白粉、炭黑及有机颜料科隆新材可配套供货，色母粒也可定制，每批附色差和耐温数据，公斤级试样支持先做配色对比。
炭黑：黑色主力。色素炭黑黑度高、分散好，做高档黑色家电外壳；普通炭黑性价比高，做管材、垃圾袋。注意炭黑要解决分散，否则表面有颗粒感。
有机颜料（酞菁蓝、永固红、联苯胺黄等）：颜色鲜艳、着色力高，做彩色日用品和包装。注意：有机颜料耐温普遍不如无机，加工温度别超其耐热窗口，否则褪色变色。
色母粒：工业化量产的标准答案。把高浓度颜料预先分散在与基材相容的载体树脂里，再加分散剂和润滑剂，双螺杆挤出造粒成颗粒状。选它的信号：批量生产、车间怕颜料粉尘、批次色差ΔE要求严、换色频繁。注意事项：载体树脂必须与基材匹配——PP基材用PE/PP载体母粒，ABS用ABS载体，错配会出现界面分层或析出；添加比例常见2%-5%，浓度太高分散不开容易出色点，浓度太低喂料误差大、单公斤成本反而上去。色母粒比干粉颜料多一道造粒工序，但省了称量、预混和车间除尘，量产综合账往往更划算。 一句话：打样试色用干粉，量产锁色用母粒，别把试产和量产混着来。
要稳定量产就上色母粒，别用颜料干粉直接往挤出机里倒。
塑料着色的终极尴尬：师傅调了一晚上色，客户说和上一批“看着不一样”。
替代对照：进口色粉和色母能不能换？先看这张表
替代的核心不是能不能调出那个色，而是能不能“每一批都调出同一个色”。下面列常见方向。
| 原用进口方向 | 典型应用 | 可对标方案 | 切换前提 |
|---|
| 进口金红石钛白粉 | 家电/户外白件 | 国产金红石型 | 对比白度、耐候、遮盖力、分散性 |
| 进口色素炭黑 | 黑色家电外壳 | 国产炭黑 | 对比黑度、分散、抗UV效果 |
| 进口有机颜料 | 鲜艳色日用品 | 国产有机颜料 | 对比色光、耐迁移、耐热窗口 |
| 进口色母粒 | 量产配色 | 国产定制色母 | 对比色差ΔE、批次一致性、分散 |
表中为应用方向参考，不代表颜色完全等同。着色替代必须用色差仪测ΔE，不能靠人眼，替代顺序走小试→对色签样→小批量→放量。
着色剂替代最看重批次色差，科隆新材寄送色母粒或颜料试样时附耐温和色差ΔE参考数据，客户可以直接打板对比，色差控制在目标范围内再谈批量。
同个色号打出来色差半个色阶？先查颜料分散和批次，别一上来就怪调机师傅。
行业场景速查：家电白和食品白不是一种白
同样是白，家电外壳白和食品包装白，要求差得远。下面按行业拆。
| 行业 | 典型制品 | 客户最先问的参数 | 推荐体系 | 认证要求 |
|---|
| 家电 | 外壳、面板、内桶 | 白度、耐候、批次色差 | 金红石钛白粉+色母 | RoHS、REACH |
| 包装 | 食品包装膜、瓶盖 | 食品级、低迁移 | 食品级颜料/色母 | GB 4806、FDA |
| 汽车 | 内外饰件 | 耐候、色差、低VOC | 无机颜料+色母 | IATF 16949、VOC |
| 玩具/日用品 | 积木、餐具 | 安全、耐迁移 | 合规有机/无机颜料 | EN71、GB 6675 |
| 建材 | 塑料管材、型材 | 耐候、色牢度 | 炭黑/无机颜料 | GB 8814 |
举个场景：做食品级白色瓶盖，客户要求无味、不迁移、符合食品接触标准。这时不能随便用工业钛白粉和普通有机颜料，要选食品级牌号，迁移和感官测试都要过。
再看一个量产场景：做汽车仪表台深色内饰件，客户要求五年暴晒不褪色、批次ΔE≤1.0、低VOC。这种活儿干粉颜料根本接不住——分散不均一批一个样，耐候也不够。行业做法是直接用耐候级无机颜料+炭黑打底，预制成ABS载体色母粒，添加3%左右喂料，再配合光稳定剂和低VOC分散剂，打板签样后锁批次供货。色母粒厂按色号批量生产，每批附色差ΔE和耐候参考数据，整车厂按季度抽测，色差问题就从“调不出来”变成“签样管到位”。
食品接触和玩具件，着色剂先过合规再谈颜色。
添加量与搭配要点：颜色稳不稳，先看分散
着色配方的规律：底色用钛白粉或炭黑打底，彩色靠有机颜料点缀，量产全部走色母粒。
着色：分散不好，颜色发花。
◆ 白/黑打底：钛白粉0.5%-3%或炭黑0.5%-2%，先把底色铺稳。
◆ 彩色调色：有机颜料0.3%-1.5%，搭配分散剂防止团聚发花。
◆ 量产配色：色母粒按目标色浓度加2%-5%，精确喂料、批次稳定。
搭配要点：颜料要配分散剂，否则在螺杆里分散不开；颜料和阻燃剂、填料之间可能互相影响着色力；不同批次颜料务必用色差仪做ΔE管控，把色差签样锁死。
一块塑料从灰白的颗粒，变成你每天握在手里的颜色——这背后，是无数次调色和配方的温柔坚持。
加工与合规红线：色差和迁移是重灾区
着色出问题，十有八九栽在分散和合规上。下面这张表把关键环节列出来。
| 环节 | 参考值 | 做错的后果 |
|---|
| 分散混合 | 颜料配分散剂，充分预混 | 分散不均→发花、色点、表面粗糙 |
| 加工温度 | 不超过有机颜料耐热窗口 | 超温→褪色、变色、色光飘 |
| 计量喂料 | 色母粒按比例精确计量 | 喂料波动→批次色差 |
| 迁移析出 | 做耐迁移/接触迁移测试 | 迁移→渗色、污染接触面 |
合规红线：食品接触要符合GB 4806和FDA 21 CFR；玩具要符合EN71和GB 6675；电子电器过RoHS和REACH；汽车件符合低VOC和IATF 16949。相关食品级符合性声明、迁移检测报告随货归档。
FAQ：采购和配色工程师最常问的五个问题
Q1：国产着色剂和色母能不能替代进口？
可以，普通家电白、黑色外壳、日用品配色，国产钛白粉、炭黑和色母粒与进口差距已经很小，批次稳定的供应商完全够用。但在汽车内外饰、高端食品接触、严苛耐候场景，进口颜料在批次一致性和耐迁移上仍有优势。替代要先拿色板做色差仪平行对色，锁定ΔE范围，再做小批量试产，确认每批一致后再放量。测试用的对照样品和色板，可以按公斤级索取，附批次色差数据一并比对。
Q2：为什么同一配方，不同批次有色差？
常见原因：颜料本身批次色光波动、分散程度不同、加工温度有别、色母喂料比例漂移。解决办法是锁死色母批次、用色差仪每批检测、保留签样，而不是靠师傅眼睛判断。
Q3：钛白粉金红石和锐钛怎么选？
户外、耐候要求高选金红石型；室内、追求柔白且成本敏感可选锐钛型。做汽车和户外建材别用锐钛，否则日晒几个月就泛黄失光。
Q4：有机颜料打出来晒久了褪色怎么办？
褪色多半是颜料耐候不够或加工温度超了耐热窗口。户外彩色件应改用耐候型无机颜料或耐候有机颜料，并配合光稳定剂；纯鲜艳色要平衡鲜艳度和耐候，别选最便宜的那种。
Q5：色母粒浓度怎么定？
色母粒浓度取决于目标颜色深浅和载体，常见添加比例2%-5%。太深的色母分散差、易色点，太浅则喂料量大致成本高。先让色母厂按你的基材和目标色打样，测色差后再定添加比例。
Q6：色母粒和干粉颜料，到底哪个更划算？
短期看干粉便宜——每吨颜料单价低，不用付母粒厂的造粒加工费。但量产算的是总账：干粉投料要人工称量、反复预混，粉尘飘在车间里不光污染环境，分散不均还会发花、出色点；换色时机筒清洗半天，色差批次靠师傅眼睛。色母粒虽然每吨贵一截，但直接按比例喂料、分散均匀、批次ΔE稳定在1以内，换色快、车间干净、返工少。结论：打样、小批量试单干粉足够；一旦上量产线、客户卡色差，色母粒那点差价早就被省下来的人工和返工费覆盖了。
选型三步清单：照着选颜色不走样
◆ 第1步·定颜色与用途：先确认目标色、耐候要求（室内/户外）、是否食品接触或玩具，这决定颜料类型和合规门槛。
◆ 第2步·选形态：打底用钛白粉/炭黑，彩色用有机或无机颜料，量产全部走色母粒，避免干粉直接投料。
◆ 第3步·锁批次与认证：用色差仪签样锁定ΔE，确认食品级、玩具、RoHS等合规文件，先小试对色再批量。
色差半个色阶，就是两批货的距离
着色剂的稳定性决定批次色差，色母粒比干粉颜料更容易控制分散和色差。科隆新材供应钛白粉（金红石/锐钛）、炭黑、有机/无机颜料及定制色母粒，可提供耐温、耐候、色差ΔE参考数据；对色差要求高的制品推荐色母粒方案，公斤级试样支持先做配色和批次稳定性对比。
去年，一家做家电外壳的厂被客户投诉批次色差——同一款蓝色，两批货放在一起明显不一样。科隆新材建议他们从干粉颜料改成色母粒，并提供了对应色号的公斤级试样。客户试产后，批次间色差ΔE从约3降到约1.2，组装线上不再出现混装色差问题。客户的采购经理说，原来多花一点色母粒的钱，省了十倍的返工费。
你的调色师傅，今晚又要加班吗？
声明：本文涉及的品牌、商标及产品名称权归各自原厂所有。本文为第三方选材知识分享，文中提及的牌号、参数、价格、认证及应用案例仅供参考，具体以各生产企业官方最新资料及批次检测报告为准。本文不构成任何采购或投资建议，读者据此操作风险自担。
For the same model of blue home appliance casing, when two batches are placed together for comparison, the color difference is visible to the naked eye—one batch leans blue while the other leans gray. After mixing on the assembly line, the client discovered it during inspection and requested all of them to be reworked and recolored. The colorist worked two consecutive nights and found out that the masterbatch used dry powder pigments directly mixed, which caused uneven dispersion, resulting in a color difference ΔE of over 3 between batches.
The white on the phone case in your hand may come from the same type of raw materials as your home's latex paint—it's just that most people have never asked.
This article is compiled by Ningbo Kolong New Materials Co., Ltd., which has long been engaged in the business of plastic raw materials and additives. The grade and batch information are subject to the actual supply channels.
Quick Reference Table of Colorants: Three Routes of Pigments, Dyes, and Color Masterbatches
Colorants are not a single thing, but a whole set of color-matching toolkits: white titanium dioxide and black carbon black as base, inorganic and organic pigments for coloring, and then industrially repackaged into masterbatches. The table below lists the mainstream varieties on one page.
| system | Representative variety | Key parameters | Typical products | Add ratio |
|---|
| white paint | Rutile/Anatase Titanium Dioxide | Type R has good weather resistance, Type A has high whiteness | Home appliances, daily necessities, boards | 0.5%-3% |
| Black paint | Pigment black | Tinted and UV-resistant | Home appliance housings, pipes, automotive parts | 0.5%-2% |
| Inorganic colored pigments | Iron oxide, ultramarine, chromium-based | Temperature-resistant and weather-resistant, with stable color tones | Outdoor components, building materials | 0.5%-3% |
| Organic pigment | Phthalocyanine Blue, Permanent Red, Benzidine Yellow | Bright colors, average temperature resistance | Daily necessities, packaging | 0.3%-1.5% |
| color masterbatch | Concentrated masterbatches of various types | Well dispersed, easy to measure | Industrial mass production | 2%-5% |
Note: The above temperature and weather resistance are common parameters. Specific color difference and migration properties should be based on the official TDS and tested samples. First determine the color and weather resistance requirements, then choose the pigment type, and finally decide whether to use color powder or masterbatch.
Figure 1 Pigments — Titanium Dioxide, Carbon Black, and Colored Pigment Particles
Colorants are the makeup artists of plastics, while masterbatch is the industrial answer.
The protagonist here is the makeup artist of plastics. Ningbo Cologne New Materials Co., Ltd. has long been engaged in various plastic additives and modified raw materials, covering sources from many domestic and international brands. It has stable supply channels for color-related products such as titanium dioxide, carbon black, and color masterbatches. The category of colorants is essentially the 'makeup artist' of plastics — it is only because of them that gray-white resin particles gain color. And for stable and clean industrial-scale production, what is relied upon is not pigment powder, but pre-made color masterbatches.
Coloring work is the same as makeup: if the base color is well-adjusted, the makeup won't go wrong right away.
From a mechanistic perspective, pigments display color by scattering and absorbing light. Titanium dioxide has a high refractive index, scattering light repeatedly to appear white; carbon black absorbs almost all light, appearing black; organic pigment molecules selectively absorb specific wavelengths, showing colors. In resins, pigments must be dispersed into very fine particles. Once they aggregate, the color becomes uneven, and spots appear on the surface. Masterbatch is made by pre-dispersing high-concentration pigments into a carrier resin to form granules, making the addition clean, dispersion uniform, and measurement convenient, which is the standard solution for large-scale production.
Sprinkle titanium dioxide particles into transparent resin, and when light hits, it bounces off repeatedly, and the whiteness just emerges like that.
Titanium dioxide is divided into two crystal types: rutile and anatase. Rutile has a higher refractive index and better weather resistance, making it the preferred choice for outdoor components; anatase has a softer whiteness but weaker weather resistance, suitable for indoor use. In addition to blackening things, carbon black can also absorb ultraviolet rays, so outdoor black components essentially get a free layer of UV protection, killing two birds with one stone.
Rutile and anatase are not the same kind of white—using anatase for outdoor parts is like letting a delicate lady face the sun; it will turn yellow in three months.
Carbon black is not just black; it is also a free UV protection helper, making outdoor black items doubly beneficial.
Quick check by variety: titanium dioxide as the base, carbon black also UV-resistant, color masterbatch for mass production
There seem to be many varieties, but capturing a few main types can cover 80% of coloring needs.
Inorganic pigments are temperature and weather resistant but the colors are dull, while organic pigments are bright but less temperature resistant; using them together makes the colors both bright and durable.
Titanium dioxide (TiO2): A white pigment used in large quantities. It is used for appliance casings, panels, and white daily necessities, with rutile type preferred; for indoor soft white or cost-sensitive applications, anatase type can also be used. Note: An excessive amount of titanium dioxide will affect impact strength and surface gloss, so it should be balanced together with fillers.
Supply Notice: Titanium dioxide, carbon black, and organic pigments can be supplied by Cologne New Materials. Color masterbatches can also be customized, with each batch accompanied by color difference and temperature resistance data. Kilogram-level samples are available for preliminary color matching.
Carbon Black: The main black pigment. Pigment carbon black has high blackness and good dispersion, used for high-end black appliance casings; ordinary carbon black is cost-effective, used for pipes and garbage bags. Note that carbon black needs to be dispersed properly, otherwise the surface will feel grainy.
Organic pigments (phthalocyanine blue, permanent red, benzidine yellow, etc.): bright colors, high coloring power, used for colored daily necessities and packaging. Note: organic pigments generally have lower temperature resistance than inorganic pigments, so the processing temperature should not exceed their heat resistance window, otherwise fading and discoloration may occur.
Color Masterbatch: The standard answer for industrial-scale production. High-concentration pigments are pre-dispersed in a carrier resin that is compatible with the base material, then combined with dispersants and lubricants, and extruded through a twin-screw extruder into pellet form. Signals to choose it: mass production, workshop concerned about pigment dust, strict batch color difference ΔE requirements, frequent color changes. Notes: The carrier resin must match the base material—PP base uses PE/PP carrier masterbatch, ABS uses ABS carrier; mismatching may cause interfacial delamination or precipitation. Common addition ratio is 2%-5%; concentration too high is hard to disperse and may cause specking, concentration too low increases feeding errors and per-kilogram costs. Masterbatch involves one extra granulation step compared to dry pigment, but saves weighing, pre-mixing, and workshop dust management; for mass production, it usually ends up more cost-effective. In short: use dry pigment for sample color testing, use masterbatch for mass color locking, don’t mix trial production with mass production.
To achieve stable mass production, use color masterbatch; don't pour pigment powder directly into the extruder.
The ultimate embarrassment in plastic coloring: the master spent the whole night adjusting the color, but the client said it 'looks different' from the previous batch.
Alternative comparison: Can imported color powder and color masterbatch be substituted? First, take a look at this chart
The core of substitution is not whether that color can be matched, but whether the same color can be matched in every batch. Below are common directions.
| Original imported direction | Typical Applications | Benchmark solution | Switch premise |
|---|
| Imported rutile titanium dioxide | Home Appliances / Outdoor White Goods | Domestic rutile type | Compare whiteness, weather resistance, hiding power, and dispersibility |
| Imported pigment carbon black | black home appliance casing | Domestic carbon black | Compare blackness, dispersion, and UV resistance |
| Imported organic pigments | Brightly colored daily necessities | Domestic organic pigments | Contrast color light, migration resistance, heat-resistant window |
| Imported color masterbatch | Mass production color scheme | Domestic custom color masterbatch | Contrast color difference ΔE, batch consistency, dispersion |
The table is for application direction reference and does not mean the colors are exactly the same. Color substitution must use a colorimeter to measure ΔE, not rely on the human eye. The substitution sequence should follow small trial → color matching sample → small batch → mass production.
When considering colorant substitutes, batch color difference is the most important factor. When Cologne New Materials sends color masterbatch or pigment samples, they include reference data for temperature resistance and color difference ΔE. Customers can directly make sample boards for comparison, and batch production will only be discussed if the color difference is within the target range.
Using the same color code, the color difference comes out to half a shade? First check the pigment dispersion and batch, don’t immediately blame the mixer.
Quick reference for industry scenarios: 'appliance white' and 'food white' are not the same white
Even though both are white, the white of home appliance casings and the white of food packaging have very different requirements. Below, we break it down by industry.
| Industry | Typical products | The parameters the customer asked about first | Recommendation system | Certification requirements |
|---|
| Home appliances | Outer shell, panel, inner drum | Whiteness, weather resistance, batch color difference | Rutile Titanium Dioxide Color Masterbatch | RoHS, REACH |
| Packaging | Food packaging film, bottle caps | Food-grade, low migration | Food-grade pigments/color masterbatches | GB 4806, FDA |
| Car | Interior and exterior parts | Weather resistance, color difference, low VOC | Inorganic pigment color masterbatch | IATF 16949, VOC |
| Toys / Daily Necessities | Building blocks, tableware | Safe and portable | Compliant Organic/Inorganic Pigments | EN71, GB 6675 |
| building materials | Plastic pipes and profiles | Weather resistance, colorfastness | Carbon black/inorganic pigments | GB 8814 |
For example: when making food-grade white bottle caps, customers require them to be odorless, non-migratory, and compliant with food contact standards. At this time, you cannot casually use industrial titanium dioxide and ordinary organic pigments; you have to choose food-grade grades, and both migration and sensory tests must pass.
Let's look at another mass production scenario: making dark interior parts for car dashboards. The customer requires that the color does not fade after five years of sun exposure, with batch ΔE ≤ 1.0, and low VOC. Dry pigment simply can't handle this job—dispersion is inconsistent, each batch is different, and weather resistance is insufficient. The industry approach is to directly use weather-resistant inorganic pigments, using carbon black as a base, pre-made into ABS carrier masterbatches, adding about 3% feeding amount, and then combined with light stabilizers and low-VOC dispersants. After making test panels and approving samples, batch-controlled supply is locked in. Masterbatch factories produce in batches according to color codes, with each batch accompanied by ΔE color difference and weather resistance reference data. The automaker conducts quarterly sampling, turning the color difference issue from 'cannot be matched' into 'sample approval controls everything.'
For food contact and toy parts, the colorant must comply with regulations before discussing the color.
Dosage and matching points: To check if the color is stable, first look at the dispersion.
The pattern of coloring formulas: the base color is primed with titanium white or carbon black, while the color is accented with organic pigments. Mass production is entirely done with color masterbatch.
Coloring: Poor dispersion, color is blotchy.
◆ White/Black Base: Titanium dioxide 0.5%-3% or carbon black 0.5%-2%, first lay the base color evenly.
◆ Color tinting: Organic pigments 0.3%-1.5%, combined with dispersants to prevent agglomeration and uneven coloration.
◆ Mass production color matching: Add 2%-5% of color masterbatch according to the target color concentration, with precise feeding and batch stability.
Key points for formulation: Pigments must be mixed with dispersants, otherwise they cannot disperse in the screw; pigments may interact with flame retardants and fillers, affecting coloring power; pigments from different batches must be controlled for ΔE using a colorimeter to lock in the color approval samples.
A piece of plastic transforms from grayish-white granules into the color you hold in your hand every day — behind this are countless gentle attempts at color mixing and formula adjustments.
Processing and Compliance Red Lines: Color Difference and Migration Are Major Problem Areas
Coloring problems are most likely due to dispersion and compliance. The table below lists the key steps.
| link; segment; part | Reference value | The consequences of doing wrong |
|---|
| Dispersed mixture | Mix pigment with dispersant and fully pre-mix | Uneven dispersion → marbling, color spots, rough surface |
| Processing temperature | Not exceeding the heat resistance window of organic pigments | Overheating → Fading, discoloration, color shifting |
| Metered feeding | Color masterbatch is precisely measured in proportion | Feeding fluctuation → batch color difference |
| Migration precipitation | Conduct endurance migration/contact migration test | Migration → staining, contamination of contact surfaces |
Compliance Red Lines: Food contact materials must comply with GB 4806 and FDA 21 CFR; toys must comply with EN71 and GB 6675; electronics and electrical appliances must comply with RoHS and REACH; automotive parts must meet low VOC requirements and IATF 16949. Relevant food-grade compliance declarations and migration test reports should be filed with the goods.
FAQ: The Five Most Common Questions Asked by Purchasing and Color Matching Engineers
Q1: Can domestic colorants and color masterbatches replace imported ones?
Yes, for ordinary household appliances with white or black shells and daily-use product colors, the gap between domestically produced titanium white, carbon black, and color masterbatches and imported ones is already very small. Suppliers with stable batches are completely sufficient. However, for automotive interior and exterior decorations, high-end food contact, and harsh weather-resistant scenarios, imported pigments still have advantages in batch consistency and migration resistance. To replace them, you need to first use color samples to do parallel color matching with a colorimeter, lock in the ΔE range, then conduct a small batch trial production, and confirm batch consistency before increasing the volume. Control samples and color boards for testing can be requested by the kilogram, with batch color difference data attached for comparison.
Q2: Why is there a color difference between different batches of the same formula?
Common reasons: fluctuations in color shade between pigment batches, differences in dispersion, variations in processing temperature, and shifts in the masterbatch feeding ratio. The solution is to lock the masterbatch batch, check each batch with a colorimeter, and keep sample swatches, rather than relying on the master's visual judgment.
Q3: How to choose between rutile and anatase titanium dioxide?
For outdoor use and high weather resistance requirements, choose rutile type; for indoor use, if you want a soft white and are cost-sensitive, you can choose anatase type. Do not use anatase for automobiles and outdoor building materials, otherwise it will turn yellow and lose gloss after a few months of sun exposure.
Q4: What should I do if organic pigments fade after being applied and exposed to the sun for a long time?
Fading is mostly due to insufficient weather resistance of the pigment or the processing temperature exceeding the heat resistance window. Outdoor colored parts should switch to weather-resistant inorganic pigments or weather-resistant organic pigments, and use light stabilizers; for pure bright colors, you need to balance brightness and weather resistance, and avoid choosing the cheapest ones.
Q5: How is the concentration of color masterbatch determined?
Masterbatch concentration depends on the target color depth and carrier, with a common addition ratio of 2%-5%. If the color is too dark, the dispersion and color spots will differ; if it's too shallow, the feed quantity will generally be costly. First, have the masterbatch sample your base material and target color, measure the color difference, and then decide on the addition ratio.
Q6: Which is more cost-effective, masterbatch or dry powder pigment?
In the short term, dry powder is cheap—the unit price per ton of pigment is low, and you don't have to pay masterbatch processing fees. But mass production is the whole deal: dry powder feeding requires manual weighing and repeated premixing, dust drifting in the workshop not only pollutes the environment but also causes uneven dispersion and spotting; During color change, the machine barrel is cleaned for half a day, and color difference batches depend on the technician's eye. Although masterbatch is a bit more expensive per ton, it is fed directly according to proportion, evenly dispersed, with batch ΔE kept within 1, enabling fast color changes, a clean workshop, and minimal rework. Conclusion: Sampling and small-batch trial dry powder are sufficient; Once the product is on the mass production line or customers are concerned about color differences, the price difference for masterbatch is already covered by saved labor and rework costs.
Three-Step Selection Checklist: Follow the color selection without deviation
◆ Step 1 · Determine color and purpose: first confirm the target color, weather resistance requirements (indoor/outdoor), and whether it comes into contact with food or toys, which determines the pigment type and compliance threshold.
◆ Step 2 · Shape selection: Use titanium dioxide/carbon black as the base layer, use organic or inorganic pigments for coloring, mass-produce all discolored masterbatches, avoiding direct feeding of dry powder.
◆ Step 3 · Lock batches and certification: Use a color difference meter to mark ΔE, confirm compliance documents such as food-grade, toy, RoHS, etc., conduct small color tests before batching.
Half a color difference means the distance between two batches
The stability of the colorant determines batch color difference; masterbatches are easier to control dispersion and color difference than dry powder pigments. Colon New Materials supplies titanium dioxide (rutile/anatase), carbon black, organic/inorganic pigments, and custom masterbatches, providing reference data for temperature resistance, weather resistance, and color difference ΔE; For products with high color difference requirements, a masterbatch solution is recommended, with kilogram-level samples supporting color matching and batch stability comparison first.
Last year, a factory specializing in home appliance casings was complained about batch color differences — the same blue product was clearly different when placed together. Kolon New Materials suggested switching from dry pink pigments to masterbatch and provided kilogram-level samples corresponding to the color codes. After the customer's trial production, the batch-to-batch color difference ΔE dropped from about 3 to about 1.2, and the mixed color difference problem on the assembly line no longer occurred. The client's purchasing manager said that spending a bit more on masterbatch saved ten times the rework costs.
Your color mixer, are you working overtime again tonight?
Statement: The brands, trademarks, and product names mentioned in this article belong to their respective original manufacturers. This article is a third-party material selection knowledge sharing. The grades, parameters, prices, certifications, and application cases mentioned are for reference only. Please refer to the latest official information and batch inspection reports from each manufacturer. This article does not constitute any procurement or investment advice. Readers are responsible for any actions based on it
