# Pigment & Filler Decks for Wearable NR Film

Human page: https://retifist.com/literature-reviews/pigment-filler-decks-wearable-nr-film

> **Safety.** Pigments and fillers change skin-contact extractables and aging chemistry; food-contact colorant lists are not wear certificates. Metal impurities (copper, manganese) consume antioxidant capacity. This article is compounding **literacy**, not a recipe card.

## Executive summary

Wearable NR film gets color and opacity from **compounding** (pigments and fillers in the latex before the film forms) or from **buying** already-colored sheet. Surface paints and undispersed powders are a different failure class. Fillers and some polymeric modifiers raise **modulus** and can cut stretch; metal impurities accelerate aging. Use this when choosing tint strategy for a cast compound versus ordering colored roll goods, or when a “paint it on” shortcut is proposed for stretchy film.

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## How color and opacity enter NR film

Three industrial routes — only two belong in wearable film design.

**Liquid latex work — compound before film formation (industrial default).** Compounding materials include optional **dyes and pigments** as Class 3 elastomer-phase modifiers alongside sulfur, zinc oxide, accelerators, antidegradants, clays, and softeners.[^1] A film from raw latex is not a saleable article until compounded.[^2] Color is part of the compound package, not an afterthought on cured film.

**Sheet-based work — buy formed, optionally pre-colored sheet.** Calendered or catalog NR sheeting may ship in standard colors. The mill already compounded and formed the film. You inherit opacity, modulus, and aging package as sold.

**Rejected for stretchy NR film — surface-only decoration.** Craft “liquid latex paint,” styrene-acrylic construction dispersion, or undispersed textile dye added after cure is not documented NR liquid-latex compounding. Industrial aqueous **pigment dispersions** marketed for rubber latex are the documented tinting path — still liquid-latex prep, not brush-on afterthought.

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## Pigment and filler identity buckets

| Bucket | Prep rule | Wearable film note |
| --- | --- | --- |
| Aqueous pigment dispersion | Add when compound stable | Vendor TDS may list rubber latex |
| Dry pigment powder | Dispersion **<5 µm** before latex[^3] | Undispersed powder shocks colloid |
| Oil-phase colorant | **o/w emulsion** first[^4] | Poor emulsion → oil spots on film |
| Mineral filler | Slurry before latex[^5] | Modulus ↑; keep load low for soft sheet |
| Polymeric filler (high-styrene SBR) | Add as latex[^6] | Tear ↑; modulus and set ↑ |

Insoluble solids and immiscible liquids must be dispersed or emulsified before latex addition or colloidal stability is upset.[^2][^3]

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## Loading trade-offs you will feel in wear

**Mineral clay.** DIXIE clay 0 → 50 phr drops tensile **3100 → 1500 psi** while stress at 500% rises **500 → 1100 psi**.[^7]

**High-styrene SBR filler.** At 20 pphr, crescent tear **1769 N/cm**, modulus at 300% **2.76 MPa**, permanent set **30%**; handbook flags modulus rise as disadvantage for some applications.[^6]

**Filler band (adhesive analogy).** Typical mineral filler **0–30 pphp**; higher load cuts tack while increasing stiffness.[^8]

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## Metal impurities and aging

Copper protection needs **2 phr total** antioxidant; coarse dispersions → uneven protection.[^9] Spec NR concentrate limits Cu/Mn at **8 mg/kg** solids (ISO 2004). Pigments can re-introduce metal catalysis.

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## Sheet-based vs liquid latex decision cues

**Liquid latex work:** batch color, opacity control, tear tuning via polymeric filler; accept prep discipline.[^3][^4][^5]

**Sheet-based work:** colored sheet without millroom; formulation audit requires vendor disclosure.

Pointers: [Sheet vs Liquid Film Pathways](/literature-reviews/sheet-vs-liquid-film-pathways); [Liquid Latex Painting vs Compounding Pigment](/literature-reviews/liquid-latex-painting-vs-compounding-pigment).

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## Endnotes

[^1]: Vanderbilt Latex Handbook — Class 3 modifiers including dyes and pigments.
[^2]: Vanderbilt Latex Handbook — latex definition; raw film needs compounding.
[^3]: Vanderbilt Latex Handbook — dispersion prep; <5 µm target; Hegman QC.
[^4]: Vanderbilt Latex Handbook — o/w emulsions; oil-spot failure mode.
[^5]: Vanderbilt Latex Handbook — mineral filler slurries.
[^6]: Polymer Latices Vol 3 — Application of Latices — §16.6.2; Table 16.12.
[^7]: Vanderbilt Latex Handbook — DIXIE clay filler curve.
[^8]: Polymer Latices Vol 3 — Application of Latices — §22.2.5 adhesive fillers.
[^9]: Vanderbilt Latex Handbook — antioxidant use; copper protection 2 phr.

<details>
<summary>Deep dive: High-styrene SBR polymeric filler (Table 16.12)</summary>

NR base compound; high-styrene SBR at 0/10/15/20 pphr; vulcanize 15 min @ 93°C.[^6]

| pphr | Modulus 300% (MPa) | Tensile (MPa) | Eb (%) | Tear (N/cm) | Set (%) |
| --- | --- | --- | --- | --- | --- |
| 0 | 0.90 | 28.6 | 880 | 1156 | 6 |
| 20 | 2.76 | 26.9 | 730 | 1769 | 30 |

</details>

<details>
<summary>Deep dive: Dispersion and emulsion prep (Vanderbilt)</summary>

Dispersions: <5 µm target; Hegman; remix before weigh-up.[^3] Emulsions: drop test QC; homogenize ≤38°C.[^4]

</details>

<details>
<summary>Deep dive: Mineral clay filler curves</summary>

DIXIE clay 0/25/50 phr CR example: tensile and stress @500% trends.[^7]

</details>