{"id":51,"date":"2026-03-16T18:52:50","date_gmt":"2026-03-16T17:52:50","guid":{"rendered":"http:\/\/www.7virides.com\/cs\/problemy\/barevne-problemy\/"},"modified":"2026-03-25T11:19:47","modified_gmt":"2026-03-25T10:19:47","slug":"barevne-problemy","status":"publish","type":"page","link":"https:\/\/www.7virides.com\/en\/mydlo\/problemy\/barevne-problemy\/","title":{"rendered":"Colour problems in CP soap: a guide to diagnosis and solutions"},"content":{"rendered":"<blockquote>\n<p><strong>TL;DR:<\/strong> Vanillin browning = normal for vanilla FOs. Bleeding pigments = neon mica problem. Fading of natural dyes = natural in alkalis. Solution: color test ahead, synthetic colors for stability, design planning.<\/p>\n<\/blockquote>\n<p>Soap color can disappoint in many ways - over-browning, color bleeding into adjacent layers, fading of the natural dye, or unexpected recoloring after aging. This page systematically covers the most common color problems with causes and solutions.<\/p>\n<h2 id=\"co-zpusobuje-hnednuti-mydla\">What causes the browning of soap<\/h2>\n<h3 id=\"vanilinove-hnednuti-nejcastejsi-pricina\">Vanillin browning: the most common cause<\/h3>\n<p>The most common cause of uniform browning. Vanillin (the fragrance component of vanilla fragrance oils) oxidizes in an alkaline environment and turns beige to dark brown.<\/p>\n<p><strong>How to tell:<\/strong> Uniform browning of the entire cross-section or surface, presence of a vanilla aroma, gradual darkening from the centre.<\/p>\n<p><strong>Factors that aggravate browning:<\/strong><\/p>\n<ul>\n<li>High vanillin content in FO<\/li>\n<li>Presence of gel phase (heat accelerates browning)<\/li>\n<li>Longer ripening = darker colour<\/li>\n<\/ul>\n<p><strong>How to fix it:<\/strong><\/p>\n<ul>\n<li>Embrace the color brown and plan a design in brown tones (chocolate, caramel, cappuccino)<\/li>\n<li>Use low vanillin FO or stabilized vanilla (some suppliers offer)<\/li>\n<li>Add titanium dioxide 1-2 tsp\/500g - helps, but not enough for high vanillin FOs<\/li>\n<li>Avoid the gel stage: chill the mould in the refrigerator. Less heat = less oxidation of vanillin<\/li>\n<\/ul>\n<h3 id=\"kurkumove-zbarveni-zbarveni-reakce-s-tio\">Turmeric coloration: coloration + reaction with TiO\u2082<\/h3>\n<p>Turmeric is stable, but when in contact with titanium dioxide (a white pigment) it reacts in an alkaline environment and produces green or grey stains.<\/p>\n<p><strong>Solutions:<\/strong> Never combine turmeric with TiO\u2082 in the same part of the soap. Separate them physically into different layers.<\/p>\n<h2 id=\"proc-barvy-migruji-krvaceni\">Why colors migrate (bleeding)<\/h2>\n<p>Bleeding (migration) occurs when a pigment or dye migrates from one colour area to an adjacent area. The result: blurred borders, smeared swirls, contamination of the white layer with the coloured one.<\/p>\n<p><strong>Causes of bleeding:<\/strong><\/p>\n<ul>\n<li>The dye is soluble in oil or water and migrates osmotically<\/li>\n<li>Neon micas are susceptible - the fluorescent components are not tightly bound to the mineral substrate<\/li>\n<li>Some pigments have too small particles that penetrate the soap structure<\/li>\n<\/ul>\n<p><strong>How to find out if the dye bleeds (test ahead):<\/strong> Prepare two-colour test soap - the dye under test next to the white soap (TiO\u2082). After 4 weeks, cut and check the interface. If white area stained to the color of the pigment being tested = bleeding.<\/p>\n<p><strong>How to fix it:<\/strong><\/p>\n<ul>\n<li>Use bleed-prone dyes only in single-colour soap<\/li>\n<li>Or as a surface sprinkling (where bleeding is not a problem)<\/li>\n<li>Substitute for iron oxides or ultramarines - they don't bleed<\/li>\n<\/ul>\n<h2 id=\"jak-prirodni-barviva-ztraceji-barvu\">How natural dyes lose their colour<\/h2>\n<p>Natural dyes are generally not stable in the alkaline environment of CP soap. See <a href=\"\/en\/soap\/soap-making-techniques\/natural-colorants-soap\/\">Natural colorants<\/a> for a complete overview.<\/p>\n<p><strong>The most common fading:<\/strong><\/p>\n<p><strong>Spirulina:<\/strong> Intense green \u2192 olive (6-8 weeks). Normal oxidation of chlorophylls.<\/p>\n<p><strong>Matcha:<\/strong> Green \u2192 yellow-brown (4 weeks). Pyrophytes unstable in alkalis.<\/p>\n<p><strong>Nettle, spinach:<\/strong> Green \u2192 olive\/brown. Chlorophyll degradation.<\/p>\n<p><strong>Beets:<\/strong> Red \u2192 orange \u2192 pale (2-4 weeks). Betanin is alkaline unstable.<\/p>\n<p><strong>What works stably from natural dyes:<\/strong> Turmeric (gold), activated charcoal (black), cocoa (brown), clays (mineral - very stable), paprika (orange).<\/p>\n<p><strong>How to work with unstable natural dyes:<\/strong><\/p>\n<ul>\n<li>Accept colour change as a natural feature<\/li>\n<li>Add dye as late as possible (late trace) - less time in alkaline environment<\/li>\n<li>Store soap in a dark place<\/li>\n<li>Use a higher dosage - even after fading the colour remains visible<\/li>\n<li>Or switch to iron oxides\/ultramarines for planned colours<\/li>\n<\/ul>\n<h2 id=\"neocekavane-barvy-fialova-seda-zelena\">Unexpected colours: purple, grey, green<\/h2>\n<p><strong>Purple from blue ultramarine + white:<\/strong> Blue ultramarine + titanium dioxide = purple or lavender. It's a deliberate effect, but it may surprise you.<\/p>\n<p><strong>The greying of the blue ultramarine:<\/strong> If the soap has been too acidic or hot, the ultramarine can go to a grayish tone. Ultramarine is only stable in neutral or alkaline environments.<\/p>\n<p><strong>Green coloration from turmeric + TiO\u2082:<\/strong> See above - chemical reaction in an alkaline environment.<\/p>\n<p><strong>Darkening of white soap:<\/strong> Too much olive oil or vegetable ingredients (chlorophyll) can cause a yellow-green coloration of white soap.<\/p>\n<h2 id=\"proc-se-barvy-nemiesuji-rovnomerne-nerovnomerne-zbarveni\">Why colors do not mix evenly (uneven coloration)<\/h2>\n<p><strong>Symptoms:<\/strong> Visible lumps of dye, streaks of varying intensity, pigment not evenly dispersed in the cross-section.<\/p>\n<p><strong>Causes:<\/strong><\/p>\n<ul>\n<li>The dye was not premixed in oil - added as a dry powder directly on the trace<\/li>\n<li>Insufficient mixing after adding dye<\/li>\n<li>Too strong trace - the dye does not have time to disperse<\/li>\n<\/ul>\n<p><strong>How to fix it:<\/strong><\/p>\n<ul>\n<li>Always premix the pigment in oil (1-2 tablespoons oil + pigment = smooth paste)<\/li>\n<li>Add to the light trace and stir well<\/li>\n<li>For safety: mini-mixer or pocket stick blender to disperse<\/li>\n<\/ul>\n<h2 id=\"neonove-fluorescencni-barvy-jasnost-a-stabilita\">Neon (fluorescent) colours: brightness and stability<\/h2>\n<p>Neon (fluorescent) micas depend on ultraviolet activation for their brightness. In soap:<\/p>\n<ul>\n<li>Neon color is more visible in outdoor light or UV<\/li>\n<li>Under normal room light, it looks less distinctive<\/li>\n<li>In alkaline environments, fluorescent components may fade over time<\/li>\n<\/ul>\n<p><strong>How to fix it:<\/strong> Accept that neon colors have a limited lifespan in CP soap. For long warranty sales, iron oxides or ultramarines are more stable.<\/p>\n<h2 id=\"co-se-stane-kdyz-se-vrstvit-barvy\">What happens when you layer paint<\/h2>\n<p>The colours have mixed in the cross section = deliberately separated layers have merged.<\/p>\n<p><strong>Causes:<\/strong><\/p>\n<ul>\n<li>The bottom layer was not sufficiently cured before the top layer was poured<\/li>\n<li>Too hot a top layer melted the bottom<\/li>\n<li>Large height difference during pouring (current) broke the bottom layer<\/li>\n<\/ul>\n<p><strong>How to fix it for layered designs:<\/strong><\/p>\n<ul>\n<li>Wait until the bottom layer reaches a \"light pudding\" state (not completely stiff, but holds its shape)<\/li>\n<li>Pour the top layer through a spoon or spatula (dampening current)<\/li>\n<li>Alternatively: lower top layer temperature when pouring<\/li>\n<\/ul>\n<p>See <a href=\"\/en\/soap\/soap-making-techniques\/soap-layering-embed\/\">Layering and embedding techniques<\/a> for the complete procedure.<\/p>\n<h2 id=\"prehledova-diagnosticka-tabulka-barevnych-problemu\">Overview diagnostic table of colour problems<\/h2>\n<table>\n<thead>\n<tr>\n<th>Symptom<\/th>\n<th>Cause<\/th>\n<th>Solution<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Even browning, vanilla aroma<\/td>\n<td>Vanillin from FO<\/td>\n<td>Plan brown tones or low-vanillin FO<\/td>\n<\/tr>\n<tr>\n<td>Green stains in white soap<\/td>\n<td>Turmeric + TiO\u2082<\/td>\n<td>Never combine<\/td>\n<\/tr>\n<tr>\n<td>Color migrates to the adjacent layer<\/td>\n<td>Bleeding pigment<\/td>\n<td>Test in advance, isolate the problematic dye<\/td>\n<\/tr>\n<tr>\n<td>Green \u2192 olive after 6 weeks<\/td>\n<td>Spirulina, matcha, chlorophyll<\/td>\n<td>Normal, accept or use clay\/oxide<\/td>\n<\/tr>\n<tr>\n<td>Blue \u2192 grey<\/td>\n<td>Ultramarine + acidic\/hot environment<\/td>\n<td>Distilled water, lower temperatures<\/td>\n<\/tr>\n<tr>\n<td>Uneven streaks\/ clumps of pigment<\/td>\n<td>Poor dispersion<\/td>\n<td>Premix in oil<\/td>\n<\/tr>\n<tr>\n<td>The layers have merged<\/td>\n<td>Bottom layer too soft<\/td>\n<td>Wait for the bottom layer to harden<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2 id=\"caste-otazky\">Frequently asked questions<\/h2>\n<p><strong>Can I prevent vanillin browning?<\/strong> There is no way to prevent them completely. You can slow it down with cold (no gel phase) or choose FO with lower vanillin.<\/p>\n<p><strong>Are natural dyes stable at all?<\/strong> Partially - turmeric, activated charcoal, cocoa, clays are relatively stable. Spirulina, matcha, beets are not.<\/p>\n<p><strong>What's the difference between pallor and bleeding?<\/strong> Fading = colour gradually loses intensity without movement. Bleeding = pigment migrates to the next layer.<\/p>\n<p><strong>Can I use bleeding pigment in a design with white layers?<\/strong> Preferably not - the bleeding will affect the white layer. Use it as a single-colour soap.<\/p>\n<p><strong>What is a paint test and how do I do it?<\/strong> Make a small batch (200g of oil) with the tested color next to the white soap. After 4 weeks, cut and see if the paint has migrated.<\/p>\n<p><strong>Why didn't my paint spread evenly?<\/strong> Most often because it has not been premixed in oil. Always premix pigment 1-2 tablespoons of oil.<\/p>\n<p><strong>See also:<\/strong><\/p>\n<ul>\n<li><a href=\"\/en\/soap\/soap-making-techniques\/natural-colorants-soap\/\">Natural colorants<\/a> - overview of the stability of natural dyes<\/li>\n<li><a href=\"\/en\/soap\/soap-making-techniques\/mica-oxides-pigments-soap\/\">Synthetic colorants<\/a> - mica, oxides, EU regulation<\/li>\n<li><a href=\"\/en\/soap-making-ingredients\/fragrance-oils-soap-making\/\">Fragrance oils<\/a> - vanillin and browning<\/li>\n<li><a href=\"\/en\/soap\/soap-making-problems\/soap-troubleshooting-encyclopedia\/\">Troubleshooting encyclopedia<\/a> - overview of all problems<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>TL;DR: Vanil\u00ednov\u00e9 hn\u011bdnut\u00ed = norm\u00e1ln\u00ed u vanilkov\u00fdch FO. Krv\u00e1cen\u00ed pigment\u016f = probl\u00e9m s neonovou mikou. Blednut\u00ed p\u0159\u00edrodn\u00edch barviv = p\u0159irozen\u00e9 [&hellip;]<\/p>\n","protected":false},"author":0,"featured_media":0,"parent":18,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"class_list":["post-51","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/pages\/51","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/types\/page"}],"replies":[{"embeddable":true,"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/comments?post=51"}],"version-history":[{"count":2,"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/pages\/51\/revisions"}],"predecessor-version":[{"id":192,"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/pages\/51\/revisions\/192"}],"up":[{"embeddable":true,"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/pages\/18"}],"wp:attachment":[{"href":"https:\/\/www.7virides.com\/en\/wp-json\/wp\/v2\/media?parent=51"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}